Inside:
Continuing Medical Education for U.S. Physicians and Nurses
CDC Recommendations Regarding
Selected Conditions Affecting
Women’s Health
U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
Centers for Disease Control and Prevention (CDC)
Atlanta, GA 30333
March 31, 2000 / Vol. 49 / No. RR-2
Recommendations
and
Reports
Inside:
Continuing Medical Education for U.S. Physicians and Nurses
Inside:
Continuing Education Examination
2 MMWR March 31, 2000
Centers for Disease Control and Prevention .................. Jeffrey P. Koplan, M.D., M.P.H.
Director
The production of this report as an
MMWR
serial publication was coordinated in
Epidemiology Program Office ............................................ Barbara R. Holloway, M.P.H.
Acting Director
Office of Scientific and Health Communications ...................... John W. Ward, M.D.
Director
Editor,
MMWR
Series
Recommendations and Reports ...................................
Suzanne M. Hewitt, M.P.A.
Managing Editor
Darlene D. Rumph-Person
Project Manager and Editor
Patricia A. McGee
Project Editor
Beverly H. Holland
Visual Information Specialist
The
MMWR
series of publications is published by the Epidemiology Program Office,
Centers for Disease Control and Prevention (CDC), U.S. Department of Health and Hu-
man Services, Atlanta, GA 30333.
SUGGESTED CITATION
Centers for Disease Control and Prevention. CDC Recommendations Regarding Se-
lected Conditions Affecting Women’s Health. MMWR 2000;49(No. RR-2):[inclusive
page numbers].
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Vol. 49 / No. RR-2 MMWR i
Foreword
As the nation’s prevention agency, CDC strives to accomplish its vision of “Healthy
People in a Healthy World...Through Prevention.” For women, this involves working to
better understand the health issues that have an adverse impact on women, dispropor-
tionately affect women, occur only in women, or have an impact on infant outcomes as
a direct result of a pregnancy-related event. Women’s health once focused primarily on
puberty, pregnancy, and menopause. Now, women’s health is recognized as being broad
in focus and warranting additional attention and study and involves not only chronic
conditions but individual lifestyle choices and environmental and organizational fac-
tors.
This publication focuses on some of the specific issues affecting women’s health:
falls and resulting hip fractures, sports injuries, breast and cervical cancer, and con-
genital toxoplasmosis. For each report, prevention recommendations and specific re-
search recommendations are provided. Much still needs to be done. The publication
addresses diverse and seemingly unconnected women’s health issues; however, these
issues are very much connected, and several themes run throughout each of the re-
ports. For example:
• Prevention — whether primary or secondary — continues to reduce or prevent
injury, disease, death, and disability. Prevention is an essential component to
maintaining health.
• Science continues to strengthen and support public health action on the individual,
local, and national level.
• Although much progress has been made in the area of women’s health to reduce
morbidity and mortality, more prevention research needs to be done.
• Public health affects every phase of our lives: how we live, work, and play.
Whether the topic is falls in the home, injuries associated with leisure or work-
related activities, screening for toxoplasmosis, or implementation of an early detection
program, prevention plays a vital role. Our partners in prevention (e.g., other health
agencies, business, education, communities, and individuals) also play a vital role by
developing and implementing prevention strategies and policies and by promoting
healthy behaviors and environments.
After reviewing each of these reports, examine current practices that have an im-
pact on women’s health where you live, work, and play. Are there opportunities for
improvement? As costs related to disease, disability, and injury continue to increase,
the role of prevention to maintain health becomes more critical. Prevention is about
staying healthy and living well—and prevention works for women.
Yvonne Green
Associate Director
Office on Women’s Health
ii MMWR March 31, 2000
Contents
Reducing Falls and Resulting Hip Fractures
Among Older Women ..................................................................................... 1
Background ...................................................................................................... 4
Scope of the Problem ...................................................................................... 4
Etiologic or Risk Factors .................................................................................. 5
Recommendations for Prevention.................................................................. 6
Primary Prevention ................................................................................... 6
Secondary Prevention ............................................................................... 8
Program and Research Agenda ...................................................................... 8
Conclusion ....................................................................................................... 9
References...................................................................................................... 10
Exercise-Related Injuries Among Women: Strategies for Prevention
from Civilian and Military Studies ............................................................... 13
Background .................................................................................................... 16
Definitions ............................................................................................... 18
Scope of the Problem .................................................................................... 18
Findings from Civilian Studies ............................................................... 18
Findings from Military Studies ............................................................... 20
Risk Factors for Exercise-Related Injuries ............................................. 20
The Relation Between Sex and Level of Physical Fitness .................... 27
Recommendations for Prevention................................................................ 27
Research Agenda ........................................................................................... 29
Research Needs ....................................................................................... 29
Conclusion ..................................................................................................... 30
References...................................................................................................... 31
Vol. 49 / No. RR-2 MMWR iii
Implementing Recommendations for the Early Detection
of Breast and Cervical Cancer Among Low-Income Women ..................... 35
Introduction.................................................................................................... 38
Scope of the Problem .................................................................................... 38
Breast Cancer .......................................................................................... 38
Cervical Cancer ........................................................................................ 40
Etiologic Factors ............................................................................................ 41
Breast Cancer .......................................................................................... 41
Cervical Cancer ........................................................................................ 42
Recommendations for Prevention................................................................ 42
Breast Cancer .......................................................................................... 42
Cervical Cancer ........................................................................................ 44
Implementation of the National Breast and Cervical Cancer
Early Detection Program ..................................................................... 45
Research Agenda ........................................................................................... 51
Conclusion ..................................................................................................... 53
References...................................................................................................... 53
Preventing Congenital Toxoplasmosis ........................................................ 57
Introduction.................................................................................................... 60
Scope of the Problem .................................................................................... 60
Burden of Toxoplasmosis in the United States ..................................... 60
Diagnosis and Treatment ........................................................................ 62
Etiologic Factors ............................................................................................ 63
Recommendations for Prevention................................................................ 64
Research Agenda ........................................................................................... 65
NWTPCT Recommendations for Research............................................ 65
CDC Priorities .......................................................................................... 65
Conclusion ..................................................................................................... 66
References...................................................................................................... 67
Exhibit ............................................................................................................ 70
Participants in the National Workshop on Toxoplasmosis:
Preventing Congenital Toxoplasmosis .................................................. 74
iv MMWR March 31, 2000
Vol. 49 / No. RR-2 MMWR 1
Reducing Falls
and Resulting Hip Fractures
Among Older Women
2 MMWR March 31, 2000
The material in this report was prepared for publication by:
National Center for Injury Prevention
and Control ............................................................... Stephen B. Thacker, M.D., M.Sc.
Acting Director
Division of Unintentional Injuries Prevention ................. Christine Branche, Ph.D.
Director
Vol. 49 / No. RR-2 MMWR 3
Reducing Falls and Resulting Hip Fractures
Among Older Women
Judy A. Stevens, Ph.D.
Sarah Olson, M.S.
National Center for Injury Prevention and Control
Division of Unintentional Injury Prevention
Abstract
Scope of the Problem: Fall-related injuries are the leading cause of injury deaths and
disabilities among older adults (i.e., persons aged ³65 years). The most serious fall
injury is hip fracture; one half of all older adults hospitalized for hip fracture never regain
their former level of function. In 1996, a total of 340,000 hospitalizations for hip fracture
occurred among persons aged ³65 years, and 80% of these admissions occurred
among women. From 1988 to 1996, hip fracture hospitalization rates for women aged
³65 years increased 23%.
Etiologic or Risk Factors: Risk factors for falls include increasing age, muscle weakness,
functional limitations, environmental hazards, use of psychoactive medications, and a
history of falls. Age is also a risk factor for hip fracture. Women aged ³85 years are
nearly eight times more likely than women aged 65–74 years to be hospitalized for hip
fracture. White women aged ³65 years are at higher risk for hip fracture than black
women. Other risk factors for hip fracture include lack of physical activity, osteoporosis,
low body mass index, and a previous hip fracture.
Recommendations for Prevention: Because approximately 95% of hip fractures result
from falls, minimizing fall risk is a practical approach to reducing these serious injuries.
Research demonstrates that effective fall prevention strategies require a multifaceted
approach with both behavioral and environmental components. Important elements
include education and skill building to increase knowledge about fall risk factors,
exercise to improve strength and balance, home modifications to reduce fall hazards,
and medication assessment to minimize side effects (e.g., dizziness and grogginess).
Program and Research Needs: Coordination needs to be improved among the diverse
Federal, state, and local organizations that conduct fall prevention activities. The
effectiveness of existing fall prevention programs among specific groups of women
(e.g., those aged ³85 years or living with functional limitations) needs careful
evaluation. New primary fall prevention approaches are needed (e.g., characterizing
footwear that promotes stability), as well as secondary prevention strategies (e.g.,
protective hip pads) that can prevent injuries when falls occur. Finally, efforts are
needed to increase collaboration among national experts from various disciplines, to
reach consensus regarding priority research areas and program issues, and to work
toward long-term strategies for reducing falls and fall-related injuries among older
adults.
Conclusion: Persons aged ³65 years constitute the fastest-growing segment of the U.S.
population. Without effective intervention strategies, the number of hip fractures will
increase as the U.S. population ages. Fall prevention programs have reduced falls and
fall-related injuries among high-risk populations using multifaceted approaches that
4 MMWR March 31, 2000
include education, exercise, environmental modifications, and medication review.
These programs need to be evaluated among older adults aged ³65 years who are
living independently in the community. In addition, secondary prevention strategies are
needed to prevent hip fractures when falls occur. Effective public health strategies need
to be implemented to promote behavioral changes, improve current interventions, and
develop new fall prevention strategies to reduce future morbidity and mortality
associated with hip fractures among older adults.
BACKGROUND
Older adults (i.e., persons aged ³65 years) are the fastest-growing segment of the
U.S. population. In 1990, 13% of the population was aged ³65 years; by 2050, this propor-
tion will nearly double to 23% (
1
). The number of persons aged ³65 years is projected to
increase from 31.0 million in 1990 to 68.1 million by 2040; for persons aged ³85 years, the
relative growth is even faster (
1
). This report summarizes current knowledge about falls
and hip fracture among women aged ³65 years and describes both primary and second-
ary strategies for preventing fall-related injuries. When discussing research results, the
term “significant” refers to a documented p-value of p £ 0.05.
SCOPE OF THE PROBLEM
Falls are the leading cause of injury deaths and disabilities among persons aged ³65
years. In the United States, one of every three older adults falls each year (
2,3
). In 1997,
nearly 9,000 persons aged ³65 years died from falls (
4
). Of those who fall, 20%–30%
sustain moderate to severe injuries that reduce mobility and independence and increase
the risk for premature death (
5
). Older adults are hospitalized for fall-related injuries five
times more often than they are for injuries from other causes (
5
), and women are nearly
three times more likely than men to be hospitalized for a fall-related injury (
5
).
The most prevalent fall-related injuries among older adults are fractures of the hip;
spine; upper arm; forearm; and bones of the pelvis, hand, and ankle (
6
). Of these, the
most serious injury is hip fracture, a leading cause of morbidity and excess mortality
among older adults (
7
). During 1988–1996, the estimated number of hospital admissions
for hip fracture increased from 230,000 to 340,000 (Figure 1). In 1996, 80% of the admis-
sions for hip fracture occurred among women (
8
).
The rate of hospitalization for hip fracture differs by sex. The hip fracture hospitaliza-
tion rate for persons aged ³65 years is significantly higher for women than men (
9
).
During 1988–1996, the rates for women increased significantly, from 972 per 100,000 to
1,356; for men, rates remained stable (
9
). A
Healthy People 2010
objective is to reduce
the hip fracture hospitalization rate among women aged ³65 years to no more than 879
per 100,000 (objective 15-28a).
Hip fracture hospitalization rates are substantially higher for white women than black
women. In 1996, the hospitalization rate for white women aged ³65 years was 1,174 per
100,000, five times the rate for black women (
9
). A
Healthy People 2010
objective is to
reduce hip fracture hospitalization rates among white women aged ³65 years to no more
than 932 per 100,000 (objective 15-28a).
The overall increase in hip fracture hospitalization rates can be explained in part by
the increasing U.S. population of very old adults (i.e., persons aged ³85 years). Today, a
Vol. 49 / No. RR-2 MMWR 5
larger proportion of the population is living to age ³85 years than in the past because of
reduced mortality from cardiovascular and other chronic diseases. Since 1987, death
rates from coronary heart disease, stroke, and cancer have declined, and the proportion
of adults aged ³70 years living with some functional limitation* has increased (
10
). Frail
older adults are twice as likely to fall as healthier persons (
11
).
Hip fractures are expensive. A recent study documented that the cost of a hip fracture
(including direct medical care, formal nonmedical care, and informal care provided by
family and friends) was $16,300–$18,700 during the first year following the injury (
12
). In
1991, hip fracture accounted for an estimated $2.9 billion in Medicare costs (
13
). On the
basis of the annual cost of hip fracture in 1984, an assumption that the average cost will
remain constant, an inflation rate of 3%–5%, and the increasing number of hip fractures,
the estimated total annual cost of hip fracture in the United States could reach $82–$240
billion by the year 2040 (
14
).
An even more important factor than the monetary cost of hip fracture is the injury’s
impact on a person’s life in the form of loss of independence and decreased quality of life.
Nationwide, only 50% of older adults hospitalized for hip fracture are able to return home
or live independently after the injury (
15,16
).
ETIOLOGIC OR RISK FACTORS
Approximately 95% of hip fractures are caused by falls (
17
). Other causes include
being knocked over and being injured in a motor-vehicle crash; <2% of hip fractures occur
spontaneously (e.g., as the result of a metabolic bone disease) (
17
). Not all falls are
*Defined as having difficulty with two or more activities of daily living.
FIGURE 1. Estimated number of hospital admissions for hip fracture among persons
aged ³65 years — United States, 1988–1996
Source: CDC’s National Hospital Discharge Survey.
1988 1989 1990 1991 1992 1993 1994 1995 1996
Year
0
50
100
150
200
250
300
350
400
Number (Thousands)
6 MMWR March 31, 2000
equally likely to cause hip fracture. Biomechanical studies have demonstrated that, al-
though both bone strength and the force of the impact are important factors, the point of
impact must be on or near the hip for a fall to cause a hip fracture (
18
).
Many factors contribute to falls and subsequent fall injury. Fall risk increases rapidly
with advancing age for persons aged ³65 years (
19
). Other fall risk factors include lack of
current or previous physical activity (
20,21
), muscle weakness or balance problems that
can contribute both to the risk for falling and the inability to break the impact of a fall
(
2,22,23
), functional limitations (e.g., difficulty with activities of daily living such as dress-
ing or bathing) (
22,24
), cognitive impairment or dementia (
2
), use of psychoactive medi-
cations (e.g., tranquilizers or antidepressants), some combinations of medications (
2,25
),
environmental factors (e.g., tripping hazards) (
26
), having fallen previously (
27
), having
more than one chronic disease (
28
), having had a stroke (
28
), Parkinson disease (
29
) or
a neuromuscular disease (
30
), urinary incontinence (
31
), and visual difficulties (
32,33
).
Less clear is the fall risk associated with wearing shoes with thick, soft soles (e.g., jogging
shoes) that can affect balance and proprioception or become a tripping hazard by catch-
ing in carpeting (
34
).
Similar to fall risk, hip fracture risk increases sharply with advancing age (
19
). Women
aged ³85 years are nearly eight times more likely than women aged 65–74 years to be
hospitalized for hip fracture (
9
). White women aged ³65 years are at higher risk for hip
fracture (
19
) than black women, in part because the prevalence and severity of
osteoporosis—a condition that predisposes to bone fragility—is greatest among white
women. Other risk factors include low body mass index (weight in kilograms divided by
height in meters squared [weight [kg]/height squared [m
2
]) (
7,35,36
), previous history of
osteoporosis (
27
), and having sustained a previous hip fracture (
27
).
Falls are caused by personal (intrinsic) and environmental (extrinsic) factors. Per-
sonal risk factors include problems with gait and balance, functional impairments or
limitations in activities of daily living, visual problems, and behavioral risk factors (e.g.,
lack of physical activity and taking certain psychoactive medications such as tranquilliz-
ers or antidepressants). Environmental factors include home hazards (e.g., clutter; no
stair railings; loose rugs or other tripping hazards; no grab bars in the bathroom; and poor
lighting, especially on stairs). Frequently, a fall is the result of an interaction between
personal and environmental factors.
RECOMMENDATIONS FOR PREVENTION
Because approximately 95% of hip fractures result from falls (
17
), minimizing fall risk
is a practical approach to reducing these serious injuries. Primary prevention of fall-
related injuries involves reducing the occurrence of falls; secondary prevention of
fall-related injuries involves preventing injuries when falls occur.
Primary Prevention
Primary prevention of fall-related injuries among older adults can be targeted to
persons living independently in the community or residents of nursing homes. Research
has established that effective fall intervention programs employ a multifaceted approach
and incorporate both behavioral and environmental elements: exercises to improve
strength and balance, environmental modifications, education about fall prevention, medi-
cation review and assessment to minimize side effects, and risk factor reduction (
36–39
).
Vol. 49 / No. RR-2 MMWR 7
Community Intervention
Approximately 90% of adults aged ³65 years live in the community and many fall
prevention programs target these persons; however, few of these programs have been
evaluated for effectiveness. During 1990–1992, a prospective, multifaceted, fall-
prevention study was conducted among 301 community-dwelling men and women who
were aged ³70 years and had at least one fall risk factor (e.g., sedative use or some
limitation in arm or leg strength) (
36
). A total of 153 persons participated in an interven-
tion that consisted of behavioral instructions and training to reduce specific risk factors
(e.g., persons with gait or balance impairments received specialized training in these
areas), exercise programs to increase strength, and medication adjustments. After 1
year, the group that received the intervention had 30% fewer falls than the control group.
Further research is needed to evaluate the effectiveness of such a program among all
persons aged ³65 years living independently in the community.
Physical Activity. Increasing physical activity can be an effective component of fall
prevention programs. Activities that improve strength, balance, and coordination can
reduce the risk for falls and fall-related injuries among healthy (
40,41
) and frail persons
(
42
). Studies have demonstrated a 40%–60% reduction in hip fracture risk with increas-
ing levels of physical activity (
36,43
). Although fall prevention programs have focused
on several techniques to improve strength, balance, coordination, mobility, and flexibility,
Tai Chi is probably the most frequently studied type of exercise (
40
). Effective programs
have been employed with persons of different ages and with varied physical abilities;
however, persons with functional limitations might require more individualized physical
activity programs (
44
).
Environmental Modifications. Because approximately 50%–60% of all falls among
older adults occur at home, fall prevention programs should address home hazards that
can contribute to falls (
45
). Home-visiting programs (e.g., those using visiting nurses)
provide opportunities to identify potential fall hazards and take corrective action. These
programs can increase awareness of fall risks among informal caregivers, (e.g., family
and friends who frequently visit the homes of older adults) and the older adults them-
selves.
Health Education. Fall prevention programs frequently include health education and
health promotion materials about reducing fall hazards that are distributed at central
locations (e.g., senior centers or health fairs). However, educational materials alone
might not promote behavioral changes. Many programs employ home-hazard checklists
that can be used by the caregiver or health agency personnel (e.g., a visiting nurse or
home health aide) to help persons identify fall hazards and to suggest corrective action
(e.g., eliminating potential tripping hazards such as clutter and throw rugs, adding stair
railings, improving lighting, adding nonslip floor surfaces, and installing grab bars in
bathrooms). Checklists are also given to residents to help them assess personal and
environmental risks and take preventive action, including behavioral changes (
45
). Re-
search is needed to evaluate and assess the effectiveness of educational materials and
home-hazard checklists to promote fall-risk reduction activities and behaviors.
Risk Factor Reduction. Approaches that address specific risk factors can supplement
fall prevention program efforts. Medical approaches might include reducing fall risk
factors (e.g., maximizing control of concomitant chronic diseases) and reducing hip frac-
ture risk factors (e.g., counseling women aged ³65 years against inappropriate weight
loss).
8 MMWR March 31, 2000
Nursing-Home Intervention
Nursing-home residents, who constitute approximately 5% of the population aged
³65 years, are at particularly high risk for fall-related injuries. Approximately one half of
the estimated 1.7 million nursing-home residents in the United States fall at least once
each year, and 11% sustain a serious fall-related injury (
46
). A randomized trial of seven
pairs of nursing homes that included 500 residents evaluated an intensive, multifaceted
intervention of extensive environmental modifications (e.g., obtaining wheel locks for
beds, changing lighting, modifying floor plans, and purchasing raised toilet seats), medi-
cation review, and increased attention to individual resident needs (
39
). Repeat falls
declined 19% among nursing-home residents who had fallen at least once during the
previous year. However, approximately one third of the safety recommendations imple-
mented in the study group were discontinued within 3 months of the completion of the
study. Strategies are needed to institutionalize fall prevention interventions in the
nursing-home setting, and additional programs designed for high-risk nursing-home resi-
dents need to be implemented and evaluated.
Secondary Prevention
Secondary prevention strategies are being developed to reduce the incidence of hip
fracture among older women (
47
). Most hip fractures are caused by falling directly on
the hip, and biomechanical studies have demonstrated that a pad that shunts the energy
away from the point of impact is highly effective in reducing the force of a fall on the
proximal femur (
48
). A 1993 clinical study in a Copenhagen nursing home demonstrated
that hip protectors reduced the risk for hip fracture by approximately 50% (
47
). During
1994–1996, researchers in Finland conducted a study to determine whether nursing-
home residents would wear an undergarment with energy-shunting hip pads. The find-
ings indicated that 63% of the residents wore the pads (
49
). U.S. manufacturers have
considered producing and marketing an undergarment with energy-absorbing hip pads,
but how acceptable and effective this garment might be among community-dwelling
older adults is unknown.
A promising technologic innovation for preventing fall-related injuries is a recently
developed safety floor (
50
). Under laboratory conditions, this flooring material provides
a firm walking surface and, if a fall occurs, reduces the force of impact through the use of
special energy-absorbing flooring material. Field trials are under way in nursing homes
to evaluate the effectiveness of this material in preventing fall-related hip fractures
among nursing-home residents.
PROGRAM AND RESEARCH AGENDA
Many professional and community-level organizations within the public health com-
munity, federal agencies, nongovernmental organizations, and state and local health
departments are involved in efforts to reduce falls and fall-related injuries among older
adults. However, coordination among these entities has been limited. CDC’s National
Center for Injury Prevention and Control has funded the National Resource Center on
Aging and Injury at San Diego State University to collect, organize, and evaluate informa-
tion and to increase awareness about preventing unintentional injuries among older
adults. Information will be available through fact sheets, formal publications, and the
Internet (at <http://www.olderadultinjury.org>) and will be provided to health-care
Vol. 49 / No. RR-2 MMWR 9
professionals, caretakers, and other persons concerned about reducing injuries among
older adults.
Researchers do not know all the factors that contribute to falls and fall-related injuries
or how personal and environmental factors interact to cause a fall. These factors have
been difficult to identify because persons frequently cannot explain the causes or cir-
cumstances surrounding fall events. In one prospective study, one fourth to one third of
the participants did not remember a fall that occurred 3–6 months earlier (
51
). Older
adults might either blame themselves for falling or consider falls to be an inevitable
consequence of the aging process. Longitudinal prospective studies are needed to accu-
rately assess the associations between fall risk factors (e.g., interactions between intrin-
sic and extrinsic factors), the occurrence of falls, and fall outcomes (e.g., frequency of
falls, whether an injury results, and level of injury severity).
To decrease the incidence and severity of fall-related injuries, injury-prevention pro-
grams for older adults need to integrate research findings into multifaceted, community-
level programs that include both implementation and evaluation components. A model
program would employ a prospective design to accurately record fall occurrences and
establish whether a fall resulted in an injury. Such a program should incorporate four
critical elements: a) education and skill-building activities to increase knowledge about
fall risk factors, b) exercise to increase strength and improve balance, c) home safety
modifications and repairs to reduce fall hazards, and d) medication review to maximize
control of comorbid conditions while reducing adverse side effects. Because persons
must take an active role to reduce their risk for falling, a model fall prevention program
should also include effective strategies to promote behavioral changes.
Because of the increasing number of persons aged ³65 years in the United States, the
need is increasing to develop an effective national plan to address the problem of falls
and fall-related injuries within the constraints of limited health-care resources. To accom-
plish this goal, efforts are needed to increase collaboration among national experts from
various disciplines (e.g., gerontologists, health educators, behavioral epidemiologists,
home designers, and ergonomic experts), to reach consensus regarding the priority
research areas and program issues, and to work toward long-term strategies for reduc-
ing falls and fall-related injuries among older adults.
Some subgroups of older adults (e.g., women aged ³85 years and older adults with
functional limitations) might have different fall-injury risks than most community-
dwelling older adults (
44
). Efforts are needed to adapt existing fall prevention programs
or develop new interventions to reduce falls in these groups. Finally, in addition to exist-
ing behavioral and environmental interventions, new fall prevention approaches (e.g.,
characterizing footwear that promotes stability and developing more effective home
lighting) need to be developed.
CONCLUSION
Persons aged ³65 years constitute the fastest-growing segment of the U.S. popula-
tion. The average life expectancy for both men and women is increasing, in part because
of healthier life styles and better control and treatment of chronic conditions (e.g., cardio-
vascular disease). Without effective intervention strategies, the number of hip fractures
will increase as the U.S. population ages.
10 MMWR March 31, 2000
Fall prevention programs have effectively reduced falls in select populations by 30%–
50%, using multifaceted approaches that include various combinations of education,
exercise, medication assessment, risk factor reduction, and environmental modifica-
tions. Such programs need to be expanded to include multiple intervention components
tailored for diverse populations of older adults and evaluated for effectiveness. In addi-
tion, secondary prevention strategies (e.g., reducing the amount of energy transferred to
the hip) are needed to prevent hip fracture when falls occur.
The problem of fall-related hip fractures will continue to increase unless effective
intervention strategies are developed and implemented to improve fall prevention inter-
ventions and expand existing programs. Older adults must take an active role in reducing
their risk for falling. Because most older adults live independently, fall prevention pro-
grams must include effective strategies to promote behavioral changes. Innovative and
effective fall prevention strategies are needed to reduce future morbidity and mortality
associated with hip fractures, increase independence, and improve quality of life for the
growing number of older adults.
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Vol. 49 / No. RR-2 MMWR 11
18. Hayes WC, Myers ER, Morris JN, Gerhart TN, Yett HS, Lipsitz LA. Impact near the hip
dominates fracture risk in elderly nursing home residents who fall. Calcif Tissue Int
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elderly: a prospective study of risk factors and risk profiles. Am J Epidemiol 1996;143:
1129–36.
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and nonexercising older women: a pilot study. Arch Phys Med Rehabil 1993;74:837–9.
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in elderly Chinese. Society of Public Health 1991;105:369–72.
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Rehabil 1996;11:9–19.
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reduce falls in nursing homes. JAMA 1997;278:557–62.
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investigation of Tai Chi and computerized balance training. J Am Geriatr Soc 1996;44:
489–97.
41. Judge JO, Lindsey C, Underwood M, Winsemius D. Balance improvements in older women:
effects of exercise training. Phys Ther 1993;73:254–65.
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for physical frailty in very elderly people. N Engl J Med 1994;330:1769–75.
43. Wickham C, Walsh K, Cooper C, et al. Dietary calcium, physical activity, and risk of hip
fracture: a prospective study. BMJ 1989;299:889–92.
12 MMWR March 31, 2000
44. Stevens JA, Powell KE, Smith SM, Wingo PA, Sattin RW. Physical activity, functional
limitations, and the risk of fall-related fractures in community-dwelling elderly. Ann
Epidemiol 1997;7:54–61.
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Vol. 49 / No. RR-2 MMWR 13
Exercise-Related Injuries Among Women:
Strategies for Prevention from Civilian
and Military Studies
14 MMWR March 31, 2000
The material in this report was prepared for publication by:
National Center for Injury Prevention
and Control ............................................................... Stephen B. Thacker, M.D., M.Sc.
Acting Director
Division of Unintentional Injuries Prevention ................. Christine Branche, Ph.D.
Director
Vol. 49 / No. RR-2 MMWR 15
Exercise-Related Injuries Among Women:
Strategies for Prevention from Civilian
and Military Studies
Julie Gilchrist, M.D.
Bruce H. Jones, M.D., M.P.H.
David A. Sleet, Ph.D.
Division of Unintentional Injury Prevention
National Center for Injury Prevention and Control
C. Dexter Kimsey, Ph.D., M.S.E.H.
Division of Physical Activity and Nutrition
National Center for Chronic Disease Prevention
and Health Promotion
Abstract
Scope of the Problem: The numerous health benefits of physical activity have been well
documented, resulting in public health support of regular physical activity and exercise.
Although beneficial, exercise also has corresponding risks, including musculoskeletal
injuries. The incidence and risk factors for exercise-related injury have been poorly
assessed in women. Many civilian exercise activities (e.g., jogging, walking, and
aerobics) have corollaries in military physical training; injury incidence and risk factors
associated with military physical training have been more thoroughly studied.
Etiologic Factors: Injury risks increase as the amount of training increases (increased
exposure). The same exercise parameters that can be modified to enhance physical
fitness (i.e., frequency, duration, and intensity) also influence the risk for injury in a
dose-response manner. Higher levels of current physical fitness (aerobic fitness)
protect the participant against future injury. A history of previous injury is a risk factor
for future injury. Smoking cigarettes has been associated with increased risk for
exercise-related injury. Studies conducted in military populations suggest that the
most important risk factor for injuries among persons engaged in vigorous weight-
bearing aerobic physical activity might be low aerobic fitness rather than female sex.
Recommendations for Prevention: Because of the limited scientific research regarding
women engaging in exercise, general recommendations are provided. Women starting
exercise programs should be realistic about their goals and start slowly at frequency,
duration, and intensity levels commensurate with their current physical fitness
condition. Women should be informed about the early indicators of potential injury.
Women who have sustained an injury should take precautions to prevent reinjury (e.g.,
ensuring appropriate recovery and rehabilitation).
Research Agenda: In general, a combination of factors affects the risk for exercise-
related injury in women. How these factors act singly and in combination to influence
injury risk is not well understood. Additional research regarding exercise-related injury
in women is needed to answer many of the remaining epidemiologic questions and to
help develop exercise programs that improve health while reducing the risk for injury.
16 MMWR March 31, 2000
Conclusion: Exercise is an important component in improving and maintaining health;
however, injury is also an accompanying risk. A review of key military and civilian
research studies regarding exercise-related injuries provides some clues to reducing
these injuries in women. Greater adherence to exercise guidelines can help decrease
these risks.
BACKGROUND
In 1996, the U.S. Surgeon General’s report on physical activity brought together for
the first time current knowledge regarding the health benefits of regular physical activ-
ity (
1
). The report concluded that persons who are inactive can improve their current
and future health by becoming moderately active on a regular basis. In addition, the
report indicated that activity does not need to be strenuous to achieve some health
benefits, but that greater health benefits can be achieved by increasing the amount
(frequency, duration, or intensity) of physical activity. Although many studies have docu-
mented the hazards of inactivity, few have assessed the adverse effects of increased
physical activity (e.g., injury). Increased physical activity increases the risk for injury.
Although opportunities for women to participate in sports and organized fitness activities
have increased substantially during the preceding century, little is known about the risks
for injuries associated with increased physical activity and exercise for women. This
report reviews key military and civilian research studies regarding musculoskeletal in-
jury associated with common weight-bearing exercise (e.g., running, walking, and aero-
bics) and provides general recommendations for preventing exercise-related injuries
among women.
Recent public health reports have reviewed the scientific evidence supporting the
association between physical activity and several health benefits (
1,2
). Documented
health benefits of regular physical activity include reducing the risk for coronary heart
disease, noninsulin-dependent diabetes, hypertension, colon cancer, osteoporosis, and
other disorders (
1
). Physical activity decreases the symptoms and might reduce epi-
sodes of anxiety and depression (
1
). In addition, regular physical activity improves physi-
cal fitness (e.g., cardiorespiratory endurance and muscle strength); reduces body fat;
and builds and maintains healthy bones, joints, and muscles (
1
). Physical activity en-
hances strength, balance, and coordination (
1
). These benefits might be particularly
important in preventing falls and maintaining independence in older adults. As a conse-
quence of these health benefits, regular physical activity is highly recommended for
women and men of all ages (
1
).
The U.S. Surgeon General’s report indicated that approximately 60% of adult women
in the United States did not engage in the recommended amount of physical activity,
and 25% did not participate in physical activity during their leisure time (
1
). Physical
inactivity is more common in women than men (
1,3
). To help increase the proportion
of persons engaged in regular physical activity, two of the
Healthy People 2010
objec-
tives are to a) reduce to £20% the proportion of persons aged ³18 years who engage in
no leisure-time physical activity (objective 22-1) and b) increase to ³30% the proportion
of persons aged ³18 years who engage in regular, preferably daily, moderate physical
activity for at least 30 minutes per day (objective 22-2). Because regular physical activ-
ity is considered essential to health, it has been included as one of the leading health
indicators for health promotion and disease prevention in the United States (
4
).
Vol. 49 / No. RR-2 MMWR 17
Although physical activity has many health benefits, exercise has corresponding in-
jury risks. Participants are at risk for exercise-related traumatic or overuse injuries. Some
of the consequences of these injuries can be long-term (e.g., osteoarthritis and adverse
health effects resulting from inactivity because of an injury). Injury causes many persons
to stop participating in exercise (
2,5
). Efforts to increase physical activity and exercise in
women must also be balanced with efforts to prevent injury.
Because lifestyles have become more sedentary and work has become less physi-
cally demanding, planned physical activity intended to improve physical fitness has
become more important. Consequently, many adults choose to participate in exercise
programs or sports. Health-related exercise programs and sports are excellent ways for
women to increase their physical activity.
Opportunities for young women to participate in sports have substantially increased
in recent decades. Since passage of the 1972 Title IX legislation that prevented sex
discrimination in educational settings, the number of young women who participate in
high school athletics has increased from approximately 300,000 during the early 1970s
to nearly 2.7 million (one in three high school women) in the 1998–99 school year (
6,7
).
This increased participation in high school athletics has fostered increased participation
in college and elite athletics as well. Women now comprise approximately one third of
all college athletes and 37% of U.S. Olympic athletes (
7
).
Many adult women participate in recreational aerobic activities. The National Sport-
ing Goods Association reported that an estimated 37.4 million women participate more
than twice a week in common aerobic activities (i.e., aerobic dance, cycling, exercise
walking, exercising with equipment, calisthenics, swimming, and running) (
8
). Walking
is the most prevalent physical activity among adults in the United States (
1,9
). If trends
of increased participation in women’s sports expand to include increased participation
in recreational and other physical activities, the number of exercise-related injuries can
also be expected to increase.
Injuries occur in association with physical activity, exercise, and sports (
10–13
), but
the incidence and underlying causes of such injuries are not well understood. At the
peak of the fitness boom in the 1980s, researchers knew little about exercise-related
injuries and injury rates, even for common activities (e.g., walking and running) (
12
).
During that period, researchers were only beginning to study the epidemiology of and
risk factors for exercise-related injuries (
12,14
). Today, injury risk factors for physically
active men remain poorly defined, and the specific risks for women who exercise are
even less understood. Studies of runners have provided the most thorough examina-
tion of injury incidence and some related risk factors in civilian populations
(
5,12,14–17
).
Studies of military populations provide sex-specific information on injury risks associ-
ated with physical training and exercise; activities are controlled, and complete and de-
tailed health records, physical examinations, and physical fitness assessments are
available (
18,19
). Studies of basic combat training, which occurs in all branches of the
military and involves running, marching, and other weight-bearing aerobic activities, can
often provide information relevant to civilian populations. Uniformity of training within
military units provides unique control for the variability observed in exercise routines in
the civilian population. Examination of military studies provides some data on exposure
risks (
18,20
) and intrinsic risk factors (e.g., sex, previous injuries, health behaviors, sports
participation, physical fitness, and anatomic factors) (
19–24
).
18 MMWR March 31, 2000
This report describes civilian and military research related to weight-bearing aerobic
exercise and injuries. Aerobic exercises (e.g., running, walking, and aerobic dance) are
highlighted in this report because they are popular and commonly prescribed activities.
Military studies of training-related injuries are presented to identify shared and sex-
specific intrinsic risk factors. Risks for men will be discussed briefly for comparative
purposes. This report focuses on modifiable risk factors, which underlie the recommen-
dations for prevention and future research.
Definitions
In this report, distinctions between the terms “physical activity,” “exercise,” and
“physical training” are important. Physical activity has been defined as movement cre-
ated by skeletal muscle contractions, resulting in energy expenditure. Exercise is a type
of physical activity that is planned, repetitive, and designed to improve or maintain at
least one of the health-related components of physical fitness (
25
). Physical training
(as used in the military) is organized exercise intended to enhance fitness. The terms
exercise and physical training are used interchangeably. Physical fitness can be cat-
egorized into five health-related components: a) cardiorespiratory endurance (aerobic
fitness), b) muscle endurance, c) strength, d) flexibility, and e) body composition (
1,25
).
The focus of this report is on exercise for women aimed at enhancing cardiorespiratory
endurance (aerobic fitness). When discussing research results from cited literature, the
terms “significant” and “not significant” refer to a documented p-value of <0.05 or
>0.05, respectively, unless otherwise stated.
Musculoskeletal injuries related to exercise can be classified as either traumatic
(acute) injuries (e.g., sprains and fractures) or overuse injuries (e.g., tendinitis, bursitis,
and stress fractures). A distinction is also made between extrinsic and intrinsic risk
factors for musculoskeletal injury. Extrinsic risk factors refer to the parameters of train-
ing (e.g., frequency, duration, and intensity) and the conditions associated with the
environment in which the exercise takes place. Intrinsic risk factors refer to the per-
sonal and internal characteristics of the participant (Table 1).
SCOPE OF THE PROBLEM
Findings from Civilian Studies
The incidence of exercise-related injury among women in the civilian population is
not well documented. Civilian studies of male and female exercise participants provide
some indication of the frequency of such injuries. Surveys demonstrate that the inci-
dence of self-reported running-related injury is high. Annually, approximately 25%–
65% of male and female runners report being injured to the extent that they reduced or
stopped training (
5,13,15–18,26
). In addition, 14%–50% of these injured runners seek
medical care for their injuries (
5,13,15–18
), representing substantial health-care costs
for treatment and rehabilitation. Prospective studies that incorporated follow-up of in-
jury among runners and other persons involved in vigorous physical activities suggest
that the incidence of injuries might be even higher (
11,27–29
).
In an 18-month study of runners training for a marathon, 85% experienced ³1 injury,
and 174 injuries were reported among the 73 participants (159 injuries per 100 runners
Vol. 49 / No. RR-2 MMWR 19
per year) (
27
). In a 12-week study of aerobic dancers, 200 (49%) of 411 participants
reported complaints associated with aerobics, and approximately 25% had to modify
or stop participation because of an injury (
28
). In a study of participants engaged in
several recreational sporting activities, 475 injuries occurred among 986 participants
during a 12-week period (192 injuries per 100 participants per year) (
11
). In a 6-month
study of walkers who averaged 14 miles per week, 21% stopped walking for ³1 week
because of injury (
29
). Although injuries during fitness activities are common, few stud-
ies of women or men who participate in recreational fitness activities are available to
quantify risk or identify modifiable risk factors.
TABLE 1. Extrinsic and intrinsic risk factors for musculoskeletal injuries associated with
weight-bearing exercise and activity*
Extrinsic factors
Training parameters (excessive or rapid increase)
Duration
Frequency
Intensity
Environmental conditions (extremes or irregular)
Terrain
Surfacing
Weather
Equipment (e.g., footwear)
Intrinsic factors
Sex
Age (extremes)
Previous injury
Behavioral factors
Smoking
Alcohol use
Previous physical activity/lifestyle (sedentary)
Physical fitness
Aerobic endurance (low)
Muscle endurance (low)
Strength (low or imbalanced)
Flexibility (extremes or imbalanced)
Body composition (extremes)
Anatomic abnormalities
High arches
Bowed legs
Leg-length discrepancies
Musculoskeletal disease
Osteoporosis
Arthritis
*Source: Jones BH, Reynolds KL, Rock PB, Moore MP. Exercise-related musculoskeletal inju-
ries: risks, prevention, and care. In: Durstine JL, King AC, Painter PL, Roitman JL, Zwiren LD,
Kenny WL, eds. Resource manual for guidelines for exercise testing and prescription. 2nd
ed. Philadelphia, PA: Lea & Febiger, 1993:378–93.
20 MMWR March 31, 2000
Findings from Military Studies
Many civilian fitness activities (e.g., walking and jogging) have corollaries in military
physical training (e.g., marching and running). The incidence of injury and related intrinsic
risk factors for these activities have been more thoroughly studied in military populations
than in civilians. Because physical fitness is required for military readiness, recruits
undergo a vigorous basic training (BT) course, and substantial research has been de-
voted to methods of enhancing fitness and understanding the causes of training-related
injuries. Studies from the U.S. Army 8-week BT have documented cumulative injury
rates from 42% to 67% among women during the course of training (
19,20,30
). Of women
in the U.S. Air Force, 33% incurred an injury during the 6-week BT (
20
). Similarly, 22% of
women in the U.S. Navy sustained an injury during the 9-week BT, and 49% of women in
the U.S. Marine Corps were injured during the 11-week BT (
20
). The range of injury
incidence (22%–67%) among women in the different services and over time might be
explained by differences in the duration and intensity of BT.
Most of the injuries to both women and men engaged in military BT are overuse
injuries (e.g., achilles tendinitis, patellar-femoral syndrome, plantar fasciitis, and stress
fractures). Most injuries occur to the lower extremities. Studies during Army BT indi-
cate that 60%–80% of BT injuries are related to overuse, and 80%–90% occur to the
lower extremities (
21,22,30
).
Injuries in the military have substantial effects on training and combat readiness
because they require greater rehabilitation and recovery time than illnesses. Approxi-
mately 50% of health-care visits in these young, vigorously active military populations
are injury-related (
20
). The rate ratios of injury-to-illness sick call visits for women in
the Army, Marine Corps, and Air Force are 1.0, 1.0, and 0.8, respectively. Furthermore,
the rates of limited duty days (i.e., days when a trainee cannot fully function on duty)
are often substantially higher from an injury than from illness (
20,24
). In one Army
study, women were assigned 129 injury-related limited duty days per 100 female train-
ees per month compared with 6 illness-related limited duty days per 100 trainees per
month. The rate ratio between injury and illness limited-duty days was 22, even though
50% of sick-call visits were for illnesses (
20
). Among men, the rates of limited duty for
injury were five times higher than the rates of limited duty for illness. In the physically
active and generally healthy military populations, injury can be expected to account for
a substantial proportion of morbidity, health-care costs, and rehabilitation time in com-
parison with illnesses. The burden of injuries among physically active civilian popula-
tions might reflect a similar pattern.
Risk Factors for Exercise-Related Injuries
Risk factors for exercise-related injuries can be either extrinsic or intrinsic to the
participant (Table 1). This report focuses on extrinsic training factors, perhaps the most
important factors in determining injury risks, and addresses selected intrinsic factors.
The association between training parameters and injury risks in civilian and military
populations will be examined first because they are potentially the most important.
Extrinsic Training Factors
The same training parameters that are modified to achieve a training effect (i.e.,
frequency, duration, and intensity of exercise) are also the most important factors re-
Vol. 49 / No. RR-2 MMWR 21
lated to injury. Several surveys of distance runners indicate a relation between a higher
number of miles run per week and a higher incidence of injury in both women and men
(
5,10,13,15,26
). Several studies have demonstrated that the relative risk (RR) of injury
among civilian women and men is a function of the miles run per week (Table 2) (
5,15,26
).
One classic study indicated that as the average weekly training mileage increased in 10-
mile increments from <10 miles per week to >50 miles per week, the incidence of injury
for women increased from 29% to 57%. The incidence of injury for men increased in a
similar manner (
5
). Two additional studies reported similar sex-specific trends (
15,26
).
The annual incidence of injury among female and male runners was approximately the
same, and the RRs of injury for both sexes increased with increasing miles run. These
and other studies suggest that, for weight-bearing exercise (e.g., running), injury rates
increase as the amount of training increases in a dose-response manner.
In a study that examined the benefits of aerobic fitness and injury risks associated
with increased duration or frequency of training among men, injury rates increased with
duration of exercise (when frequency and intensity remained constant). Participants
received limited additional aerobic fitness benefits when they exercised 45 minutes
compared with 30 minutes. As duration of running increased from 15 minutes to 30
minutes to 45 minutes per workout, injury rates increased from 22% to 24% to 54%,
respectively, whereas aerobic fitness (measured by maximal oxygen uptake) improved
only 9%, 16%, and 17%, respectively. Although a plateau in fitness occurred, more exer-
cise increased the incidence of injury. This study also demonstrated that frequency of
exercise (number of training sessions per week), although positively related to aerobic
fitness, was also positively related to injury (
31
).
A similar study of male walkers and joggers demonstrated that injury rates were
more related to total mileage walked and jogged than to the intensity of exercise. This
study controlled the total amount of activity in two groups of participants during a 6-
month period. Both groups exercised the same duration per day (30 minutes); however,
the walkers exercised more frequently (more days per week) than the joggers to accu-
mulate approximately the same mileage. The walkers averaged 120 minutes of exercise
per week, and the joggers averaged 90 minutes per week; however, the total distance
accumulated by both groups was approximately the same (13.7 km per week and 14.7
km per week, respectively). At the end of the 6-month study period, the two groups had
similar injury rates: 21% of the walkers and 25% of the joggers had sustained injuries
sufficiently severe to require terminating their activity for ³1 week (
29
). Studies such as
these indicate that the total amount of training is an important determinant of injury risk.
These studies were conducted with men, and similar studies of women are needed.
Studies of military populations have also examined the relation between training
frequency and duration, gains in cardiorespiratory fitness, and injury risk. As mileage
during physical training increases, both aerobic fitness and the risk of injury increases.
Similar to the findings in civilian populations (
31
), military studies have documented
thresholds in physical training, above which increased training does not improve fitness
levels but continues to increase the likelihood of injury (
18–20
). These studies of military
populations examined the association between training parameters and injury risk among
men only. Additional studies among women are needed.
22 MMWR March 31, 2000
TABLE 2. Relative risk for injury among civilian distance runners as a function of miles run per week, by study and sex —
United States
Miles Miles Miles Miles Miles Miles
Annual per per per per per per
Name Sex/No. incidence Measure week week week week week week p-value
of study in study (% Injured) of Injury <10 10–19 20–29 30–39 40–49 ³50 for trend
Koplan* Male (% Injured) 21% 29% 36% 41% 52% 71%
688 37% Risk ratio 1.0 1.4 1.7 2.0 2.5 3.4 <0.0000
Female (% Injured) 29% 32% 41% 53% 36% 57%
725 38% Risk ratio 1.0 1.1 1.4 1.8 1.2 2.0 <0.0003
Macera
†
Male Odds ratio 1.0 1.8 2.0 2.7 5.0 NA
§
NA
485 52% (95% CI
¶
) Reference (0.9–3.3) (1.1–3.8) (1.4–5.7) (2.4–10.6) NA
Female Odds ratio 1.0 0.8 1.4 5.9 2.1 NA NA
98 49% (95% CI) Reference (0.2–2.7) (0.4–5.2) (1.1–30.1) (0.5–9.5) NA
Walter** Male Relative risk 1.0 0.9 1.4 1.3 2.2 NA NA
985 49% (95% CI) Reference (0.4–1.6) (0.8–2.4) (0.7–2.3) (1.3–3.7) NA
Female Relative risk 1.0 1.0 1.4 2.0 3.4 NA NA
303 46% (95% CI) Reference (0.4–2.2) (0.6–3.2) (0.8–4.8) (1.4–7.9) NA
*Sources: Koplan JP, Powell KE, Sikes RK, Shirley RW, Campbell CC. An epidemiologic study of the benefits and risks of running. JAMA 1982;248:3118–21.
†
Macera CA, Pate RR, Powell KE, Jackson KL, Kendrick JS, Craven TE. Predicting lower extremity injuries among habitual runners. Arch Intern Med 1989;149:
2565–8.
§
Not applicable. No persons participated at the ³50-mile-per-week level.
¶
Confidence interval.
** Source: Walter SD, Hart LE, McIntosh JM, Sutton JR. The Ontario Cohort Study of Running-Related Injuries. Arch Intern Med 1989;149:2561–4.
Vol. 49 / No. RR-2 MMWR 23
Intrinsic Training Factors
Military BT provides a unique opportunity to study some intrinsic risk factors for
exercise-related injuries. Unlike civilian fitness participants, regimentation in military
training requires that trainees do the same type and amount of training. Researchers
studying military populations have systematically examined several intrinsic factors
and their relation to musculoskeletal injury risk. The most consistently identified intrin-
sic risk factors have been a) sex, b) age, c) history of previous injury, d) adverse health
behaviors (e.g., smoking tobacco), e) previous physical activity (e.g., sedentary lifestyle),
and f) current level of physical fitness.
Sex. Sex has consistently been identified as a risk factor for injury in military BT. In
studies from the 1980s to 1997 that examined women and men at the same training site
who performed essentially the same physical training, incidences of injuries for women
were 1.7–2.2 times higher than those for men (
19,20,21,30,32,33
) (Table 3).
In addition, rates of some specific injuries during military training (e.g., stress frac-
tures) are higher for women than men (
20,24,30,33,34
). In Army training, RR for stress
fractures is 2–10 times higher for women than men engaged in the same training regi-
men (
20,21,30,34–36
). In the Marine Corps recruit training, the risk for stress fractures
is 3.7 times higher for women than men (
20
).
Some specific injuries (e.g., anterior cruciate ligament tears in the knee) occur more
frequently in female athletes (
37
). However, in studies comparing civilian runners (the
most extensively studied civilian recreational fitness activity), the overall rates of
exercise-related injury are similar among women and men. Researchers suggest that
female civilian runners have the same injury rates as men because they can modulate
their training frequency, duration, and intensity (unlike military trainees) to accommo-
date their fitness levels and the minor overuse injuries that might occur (
10
). Injury
studies among military populations suggest that without controlling for physical fitness,
at any fixed level of activity, women will be at greater risk for injury than men (Table 3).
TABLE 3. Cumulative incidence of injury during basic training among women and men, by
U.S. military branch and risk ratio for ³1 injury — United States*
Duration
of basic
Branch of U.S. training Women Men Risk ratio
Year military (weeks) No. (% Injured) No. (% Injured) (³1 injury)
1980 Army 8 347 (54) 770 (26) 2.1
1982 Army 8 767 (42) 3,437 (23) 1.8
1984 Army 8 186 (50) 124 (28) 1.8
1988 Army 8 352 (62) 509 (29) 2.1
1993 Army 8 174 (67) 0 NA
†
NA
1997 Army 8 388 (63) 685 (37) 1.7
1995 Navy 9 4,415 (22) 9,500 (11) 2.0
1995 Marine Corps 11 1,498 (49) 396 (29) 1.7
1995 Air Force 6 5,250 (33) 8,656 (15) 2.2
* Sources: Jones BH, Shaffer RA, Snedecor MR, eds. Atlas of injuries in the U.S. Armed Forces. Mil Med
1999;164(suppl): 6-1–6-89.
Knapik JJ, Sharp MA, Canham ML, et. al. Injury incidence and injury risk factors among U.S. Army basic
trainees (including fitness training unit personnel, discharges, and newstarts), Ft. Jackson, SC, 1998. Ft.
Jackson, SC: Epidemiological Consultation Report, 1999; report no. 29-HE-8370-98.
†
Not applicable.
24 MMWR March 31, 2000
Age. Results of military studies regarding the effects of age on training and injuries
have been inconsistent. Some studies have revealed that during BT, female (
38
) and
male trainees aged >23 years are at greater risk for injury (
22,38,39
). Other military
studies have indicated no statistically significant difference in injury risk by age
(
20,36,40
). Studies of civilian runners have also had inconsistent results. Some studies
have demonstrated that age is not an important risk factor, whereas others have dem-
onstrated that rates of injury decrease with age (
10,13,15,16,26
). Among civilian
women, older age was not associated with elevated risk (
10
). Unlike military trainees,
older participants in civilian studies might have been able to decrease their risk by
modulating the frequency, duration, or intensity of their personal training regimens
(
10
). Alternatively, a “survivor effect” might exist, whereby persons who have sus-
tained injury change activities or cease participation and thus are unavailable for inclu-
sion in studies (
10
). Data from military and civilian studies suggest that among adults
aged <45 years, age alone is not a strong predictor of injury in exercise.
History of Previous Injury. A history of previous musculoskeletal injury has also been
reported as a risk factor for injury in both civilian and military studies. In a systematic
review of the literature regarding the prevention of ankle sprains in sports, the most
commonly identified risk factor for an ankle sprain was a previous ankle sprain (
41
).
Overuse injuries occurred twice as frequently in trainees with a previous history of ankle
sprain (
19
). A previous ankle sprain is also a risk factor for injuries among male trainees
in Army BT (
22
). In addition, data from the Marine Corps suggest that previous injuries
pose a risk for future injury (
20,40
). These findings are consistent with civilian studies of
female and male distance runners, in which RR for an injury in a person who has had an
injury during the preceding year was 1.8–2.4 for women and 1.7–2.7 for men (
15,26
).
Health-Related Behaviors. Health behaviors engaged in before entry into military
service (e.g., smoking tobacco and participating in regular physical activity) can influence
a woman’s injury risk during BT.
Smoking.
Both female and male smokers who participate in Army or Marine Corps
BT are at a significantly higher risk for injury than nonsmokers (
20
). Women who were
smokers on entry into the Army were 25% more likely to be injured in BT; injury rates
were 77% for smokers and 62% for nonsmokers (
20
). Similarly, the risk for injury among
women in the Marine Corps who smoked before beginning BT was 1.7 times higher
than for those who were nonsmokers (
20
). Male smokers in Army and Marine Corps
BT were 1.9 times and 2.3 times more likely to have an injury, respectively, than their
nonsmoking male counterparts (
20,22
). Studies have not indicated whether civilian
athletes or exercise participants who smoke tobacco are at greater risk for injury. How-
ever, in a literature review of the potential association between smoking and injuries,
researchers estimated that smokers were two times more likely than nonsmokers to
sustain unintentional injuries in the workplace, although some of these injuries might
not be related to physical activity (
42
). Data from these studies suggest that women
who smoke are at a higher risk for training-related injuries than women who do not
smoke.
Previous Physical Activity.
Although some health behaviors (e.g., smoking) might
increase injury risk, previous regular physical activity might be protective against in-
jury. This protective effect has been documented in men in the Army and Marine Corps
(
20–22,32,39
). Among male trainees in the Army, running before entry into the service
might be protective. For military women, the association between previous regular physi-
Vol. 49 / No. RR-2 MMWR 25
cal activity and injury risk has not been documented (
20,32,36
). Researchers docu-
mented that, for men, more years of participating in running was protective against
injury; however, for women, more years of participating in running might be associ-
ated with higher risk for injury (
15
). These results are difficult to interpret because of
possible survivor effects (e.g., injured runners cease to run). Because no comparable
data in civilian populations of women exist, no conclusions can be drawn regarding the
influence of previous regular physical activity as a protective factor against injury among
women. Further research is needed regarding the influence of previous physical activi-
ties and exercise-related injury risk among women and men in both military and civil-
ian populations.
Current Level of Physical Fitness. A person’s current level of physical fitness has
been one of the most important predictors of injury in military studies (
19–
21,24,32,33,40
). Of the five health-related components, low levels of aerobic fitness
and, to a lesser extent, low muscular endurance have consistently been associated
with injury risk during BT. Other factors (e.g., body composition and strength) demon-
strated weaker and less consistent associations with injury risk.
Aerobic fitness, as measured by timed performance of 1- to 2-mile runs during Army
or Marine Corps physical fitness entry tests, has been the single most consistently and
strongly associated intrinsic risk factor for subsequent training-related injury. During
Army BT, women who scored in the slowest quartile on the initial entry physical fitness
test experienced 1.5–1.7 times greater injury risk than women in the fastest quartile
(
21,36
) (Table 4). Findings were similar for women in Marine Corps BT: women in the
slowest quartile experienced 2.4 times greater risk for injury than women in the fastest
quartile. Women and men with the slowest run times (i.e., least aerobically fit) were
consistently at greater risk for injury than those with the fastest run times (i.e., most
aerobically fit). Comparable trends were documented among female Army cadets at
West Point Academy, New York (
24
). Among men, the inverse relation of aerobic fitness
and injury risk is similar to that of women. Male trainees with slower run times were at
greater risk for injury than those who ran the fastest (
20,36
).
In addition to being at greater risk for injury, women who had the slowest run times
experienced 2.5 times the risk of stress fractures and stress reactions compared with
women who had faster run times (
20,32
). Similar findings were documented among
women in Marine Corps BT (
20,40
). Researchers demonstrated that the least aerobi-
cally fit and least physically active trainees were 3.5 times more likely than persons
who were the most fit and most active to sustain a stress fracture (
23
).
A prospective study of Army trainees in BT demonstrated an association between
maximal oxygen consumption (ml O
2
per kg body weight per minute), which is a mea-
sure of aerobic fitness, and subsequent risk for injury. Maximal oxygen consumption
(VO
2
max) was measured in trainees running on a treadmill before the start of BT. For
women in successive tertiles of VO
2
max, risk for injury increased from 39% in the
highest tertile to 50% in the middle tertile, to 55% in the lowest. Similarly, men with the
lowest VO
2
max were at greatest risk for injury (36). Prospective studies among civilians
examining the association between aerobic fitness and injury are not available. Military
research suggests that higher levels of baseline physical fitness is protective, at least at
the start of a training program. Further research is needed to determine the degree and
duration of this protection.
26 MMWR March 31, 2000
Higher levels of muscular endurance and strength can also be protective against
injury in military BT. For both women and men, greater muscular endurance (mea-
sured by the number of push-ups completed in 2 minutes) was associated with fewer
training-related injuries (
20
). When categorized into quartiles, risk for injury decreased
for women who could do more push-ups. The cumulative incidence of injury was 57%
for women who completed the least number of push-ups in 2 minutes and 38% for
women who did the most push-ups. Similarly, Army women who could not lift >34 kg
had RR for injury of 1.4 compared with women who could lift >46 kg (
20
).
The relation of body composition to exercise-related injury risk is complex. Some
studies indicate no association between body composition and exercise-related injury
risk (
20,36
). When an association between measures of body fat and injury incidence
for women in Army BT has been identified, the relation has been bimodal (U-shaped).
Women with the least and the most body fat were at greater risk for injury (
21,32,40
).
Among women in Army BT, the risk for injury varies by body mass index (BMI). To
obtain BMI, weight in kilograms is divided by height in meters squared (weight [kg]/
[height squared [m
2
]). The cumulative incidence of injuries in successive quartiles of
increasing BMI were 56% (lowest quartile), 46%, 38%, and 63% (highest quartile). The
corresponding RRs were 1.5, 1.2, 1.0, and 1.6, respectively. BMI for women ranged from
18 kg/m
2
to 27 kg/m
2
(
32
). A study of civilian male distance runners demonstrated a
statistically significant bimodal relation between BMI and injury (
16
). A study of civilian
female runners indicated a statistically not significant but also bimodal relation between
BMI and injury (
15
). Additional research is needed to better determine the relation
TABLE 4. Injury risk during U.S. military basic training, by level of aerobic fitness
measured by run times of initial physical fitness tests, and by U.S. military branch —
Ft. Jackson, South Carolina, 1984 and 1998, and Parris Island, South Carolina, 1993
Location
Sex/No. Branch of and year Measure Quartile 1 Quartile 4 p-value
in study U.S. military of study of injury (fastest) Quartile 2 Quartile 3 (slowest) for trend
Women Army Ft. Jackson Injury risk 36% 33% 57% 61% 0.03
79 1984* Risk ratio 1.0 0.9 1.6 1.7
Men Army Ft. Jackson Injury risk 14% 10% 26% 42% 0.02
140 1984* Risk ratio 1.0 1.4 1.9 3.0
Women Army Ft. Jackson Injury risk 39% 55% 59% 60% 0.02
680 1998
†
Risk ratio 1.0 1.4 1.5 1.5
Men Army Ft. Jackson Injury risk 21% 23% 32% 30% 0.01
488 1998
†
Risk ratio 1.0 1.1 1.5 1.4
Women Marine Parris Island Odds ratio
¶
1.0 2.2 2.2 2.4 NA**
265 Corps 1993
§
(95% CI) Reference (1.1–4.4) (1.1–4.5) (1.2–5.1)
Men Marine Parris Island Odds ratio
¶
1.0 2.1 1.3 2.1 NA
369 Corps 1993
§
(95% CI) Reference (1.1–4.2) (0.6–2.6) (1.1–4.3)
*Sources: Jones BH, Bovee MW, Knapik JJ. Associations among body composition, physical fitness, and injury
in men and women Army trainees. In: Marriott BM, Gumstrup-Scott J, eds. Body composition and physical
performance. Washington DC: National Academy Press, 1992:141–72.
†
Knapik JJ, Sharp MA, Canham ML, et. al. Injury incidence and injury risk factors among U.S. Army basic
trainees (including fitness training unit personnel, discharges, and newstarts), Ft. Jackson, SC, 1998. Epide-
miological Consultation Report, 1999; report no. 29-HE-8370-98.
§
Jones BH, Shaffer RA, Snedecor MR, eds. Atlas of injuries in the U.S. Armed Forces. Mil Med 1999;164(suppl):
6-1–6-89. Kimsey Jr CD. The epidemiology of lower extremity injuries in United States Marine Corps recruits
[Dissertation]. Columbia, SC: University of South Carolina, 1993.
¶
Derived from logistic regression.
**Not applicable.
Vol. 49 / No. RR-2 MMWR 27
between body fat, BMI, and incidence of injury; these studies should control for physical
fitness and previous physical activity.
The Relation Between Sex and Level of Physical Fitness
The observation that low levels of physical fitness on entry into BT is related to
injuries during BT is particularly relevant to the issue of injuries among women. The
incidence of injuries among women in Army BT is consistently 1.6–2.1 times higher
than the incidence for men in Army BT. However, several studies also document that on
entry into the Army, women are less physically fit than men (
20,21,32,35,43
). On aver-
age, women have slower run times, perform fewer push-ups, and have a higher per-
centage of body fat than men.
What would be the effect of controlling for level of fitness when making compari-
sons between men and women? In several studies, injury risks were stratified by
quartiles or quintiles of run times to enable comparison of groups of women and men
who performed similarly on the initial-entry physical training test (
20,32,35,43
). In these
studies, initial RRs of injury for women were higher than for men, with RRs ranging
from 1.6 to 2.1. However, when stratified by aerobic fitness (run times), the stratum-
specific risk ratios all approached 1.0, and the summary risk ratios declined (range =
0.9–1.2). In a logistic regression model that controlled for physical fitness (i.e., run times,
numbers of push-ups and sit-ups, and strength), age, and race, the odds ratio for women
versus men was 1.1 (
20,43
). Slower run times were the only component of fitness
associated with increased odds of injury. Odds of injury progressively increased for
successive quintiles of run time from fastest to slowest: 1.0, 1.4, 1.5, 2.5, and 3.2, re-
spectively. In another logistic regression model, female sex was initially a risk factor,
with an odds ratio of 2.5 for women compared with men, until run time was entered
into the model. When corrected for run times, the odds ratio for females declined to 1.0;
however, run time remained a significant predictor (
32
). These findings suggest that
the most important underlying risk factor for injuries among military trainees engaged
in vigorous aerobic weight-bearing activities (e.g., running and marching) is aerobic
fitness level and not female sex (
33,43
). Studies that compare injury risks between men
and women with similar fitness levels have not been conducted in civilian populations.
Because the findings in this report are derived from studies of special populations
(e.g., runners and military trainees), they might not be generalizable to other U.S. popu-
lations. A review of the studies in these special populations provides guidance toward
establishing general principles that will be valuable in preventing injuries and guiding
research in the general population.
RECOMMENDATIONS FOR PREVENTION
Scientific research regarding injuries related to physical training and exercise has
focused on men rather than women, on military trainees rather than physically active
civilians, and on competitive rather than recreational athletes. In addition, the studies of
military populations generally involve a young, healthy population. Studies of recre-
ational athletes in the civilian population are difficult to conduct and might not be able
to completely control for the frequency, duration, and intensity of activity, as is possible
in studies of military populations. In addition, measures of current physical fitness might
be difficult to obtain.
28 MMWR March 31, 2000
Based on the limited scientific research regarding physical activity, exercise, and
injuries among women and generally agreed on “best practices,” the following recom-
mendations are made to reduce the risk of exercise-related injury among women:
• Although most healthy women do not need to visit their physician before starting
a moderate-intensity exercise program, women aged >50 years or women who
have either a chronic disease or risk factors for a chronic disease should consult
their physician to ensure that their exercise program is safe and appropriate.
• The choice of an exercise program should be tailored to a woman’s current
physical fitness level. Resources that include examples of activities categorized
by exercise intensity levels are available and can aid women in choosing
activities based on their respective physical fitness levels.
• Decisions regarding the frequency, duration, and intensity of exercise should be
individualized, based on the woman’s current level of physical fitness, history of
physical activity, and history of injury.
• Women, particularly those with lower fitness levels, should begin participating in
exercise at a lower level of training (frequency, duration, and intensity) and
progress slowly. Women who are sedentary and start a new exercise program or
activity might need to begin with intervals of activity as short as 5–10 minutes of
light-intensity activity and gradually increase to the desired intensity and/or
duration of participation.
• Participants should be aware of early signs of potential injury (i.e., increasing
muscle soreness, bone and joint pain, excessive fatigue, and performance
decrements). Coaches, personal trainers, and instructors should be alert to these
signs among the women they are supervising.
• When a participant senses any of the warning signs (i.e., increasing muscle
soreness, bone and joint pain, excessive fatigue, performance decrements, or
current injury), she should incrementally decrease training (i.e., reduce
frequency, duration, or intensity) until symptoms diminish or cease participation
temporarily, depending on the severity of injury.
• Women who sustain a musculoskeletal injury should allow sufficient recovery
and rehabilitation time and take precautions to prevent reinjury.
• Women who smoke should be informed that smoking might increase their risk
for exercise-related injury. They should make every effort to stop smoking, not
only to reduce their risk for injury, but also to enhance their long-term overall
health.
• Women should be realistic in setting their exercise goals by balancing the desire
for measurable weight reduction, increases in endurance or strength, or other
health-related fitness benefits with the risk for injury.
Vol. 49 / No. RR-2 MMWR 29
RESEARCH AGENDA
Research Needs
This report provides an overview of the relation between extrinsic training factors,
selected intrinsic factors, and musculoskeletal injury risks during exercise. Some re-
search exists regarding exercise-related injury risk factors among military or elite ath-
letic populations; however, little research has been conducted among other physically
active populations. Even less research specifically addresses the particular risks to
women who exercise. These gaps in current knowledge limit the specificity with which
recommendations can be made. Future research is needed to identify methods of pro-
moting physical activity while preventing or reducing the risk for injury. As researchers
continue to define the benefits of regular exercise, the following suggestions might
help develop complementary research regarding injury risks:
Surveillance systems need to be developed to monitor physical fitness, health, in-
jury, and other medical outcomes of physical activity and exercise. Questions regard-
ing exercise-related injuries need to be incorporated into existing surveillance instru-
ments that monitor physical activity participation levels. Measures of exposure in physi-
cal activity (i.e., frequency, duration, and intensity) by sex, age, and activity should be
incorporated into data-gathering systems to better characterize population-based in-
jury risks.
Research regarding the etiology of exercise-related injuries is needed to determine
the incidence of and risk factors for injuries in common exercise activities (e.g., walking,
hiking, bicycling, and aerobic dance) and active sports (e.g., tennis, racquetball, basket-
ball, and soccer) for women. Identification of the amount (i.e., frequency, duration, and
intensity), type (e.g., jogging, walking, biking, and dancing), and progression of exercise
that is appropriate for women of differing physical fitness levels and body composition
is needed to maximize fitness while minimizing injury risk. To prevent overuse injuries
among women, the appropriate amounts and balance of training and recovery for dif-
ferent types of exercise and activity need to be determined. In addition, sex-specific
exercise-related injury risks need to be determined to guide the choices women make
regarding exercise. These risks include but are not limited to a) anterior cruciate liga-
ment rupture, b) stress fractures, c) pregnancy and postpartum injury risks, and d) risks
(and benefits) of exercise in older women and women with osteoporosis.
Conducting longitudinal intervention trials to monitor injury occurrences while mea-
suring changes in fitness is essential for developing and evaluating injury reduction
measures. Determination of the long-term effects of exercise-related injuries on health
outcomes (e.g., osteoarthritis, late or chronic sequelae, and disability) and future exer-
cise participation is needed because a decrease in physical activity might increase the
risk for chronic diseases. Finally, to document the impact of exercise-related injury and
the importance of further research, the economic and social costs of
exercise-related injury and any resultant nonadherence to exercise regimens need to be
determined.
30 MMWR March 31, 2000
CONCLUSION
Persons who participate in vigorous exercise might incur a higher number of muscu-
loskeletal injuries than more sedentary persons. However, several intrinsic and extrinsic
factors interact to modify the risk for incurring an exercise-related injury. For activities
other than running and military training, little data are available regarding the incidence
or risk factors for such injuries. The data suggest that a combination of factors (e.g., sex,
current level of fitness, previous exercise experience, smoking, previous injury, and
body composition) might affect the risk for exercise-related injury in women. However,
how these factors act singly and in combination to influence injury risk is not well under-
stood. The following conclusions might help in the development of further research re-
garding the relation between exercise and the risk for injury:
• The most important risk factors for exercise- or training-related injuries are the
frequency, duration, and intensity of the physical training activity. The total
amount of exercise (e.g., the frequency, duration, and intensity) is the most
consistently identified predictor for injury risk.
• Physical fitness is inversely related to injury risk; as physical fitness level
increases, risk for injury decreases. Men and women who participate in the same
activities and have the same physical fitness levels generally have similar
incidences of injury. Thus, physical fitness rather than female sex is the
underlying risk factor.
• A dose-response relation exists between the amount of weight-bearing exercise
performed and the risk of injury for both women and men.
• A training threshold exists, above which increased training does not appreciably
increase fitness but will substantially increase risk for injury. This threshold
might be different for each person.
• Although higher current amounts of exercise or physical activity are risk factors
for injury because of increased exposure, at any fixed amount of activity, men
with a history of higher amounts of physical activity are at lower risk for injury.
For women, the relation is unclear.
• At any given amount of aerobic weight-bearing activity, women and men who
have the highest aerobic fitness levels can be expected to have lower subsequent
injury rates.
• The combined findings of research regarding the association of training,
previous physical activity, and current physical fitness levels suggest that
tailoring exercise to accommodate a person’s current level of fitness and
previous physical activity reduces injury rates. Changes in frequency, duration,
or intensity of exercise can have cumulative effects on injury risk. These findings
are particularly important for persons who are the least fit or most sedentary
because they are at the greatest risk for injury when initiating physical activity.
• The protective effect against injury of higher levels of aerobic fitness provides an
incentive to become more physically active. It suggests that incremental
Vol. 49 / No. RR-2 MMWR 31
increases in fitness are beneficial in terms of increasing health benefits and
decreasing injury risks.
• The relation between previous injuries and higher risk for subsequent exercise-
related injuries provides some indication of the importance of a) recovery and
rehabilitation and b) consideration of the history of previous injuries when
planning exercise programs.
• The association between smoking tobacco and higher exercise-related injury
risks suggests another possible reason to discourage smoking, both for injury
reduction in the short-term and increased overall health benefits in the long-
term.
• Although the association of body composition with exercise-related injury risks
is not completely clear, the bimodal relation that exists suggests that proper
maintenance of body weight in the normal range (i.e., BMI 18.5 kg/m
2
–24.9
kg/m
2
) is important not only for health and appearance but also to reduce risks
for injury.
Further research is needed to answer many of the remaining epidemiologic ques-
tions and to help develop exercise programs for women that improve health while
reducing the risk for injury.
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34 MMWR March 31, 2000
Vol. 49 / No. RR-2 MMWR 35
Implementing Recommendations for the
Early Detection of Breast and Cervical Cancer
Among Low-Income Women
36 MMWR March 31, 2000
The material in this report was prepared for publication by:
National Center for Chronic Disease Prevention
and Health Promotion ................................................................. James S. Marks, M.D.
Director
Division of Cancer Prevention and Control ................................. Nancy C. Lee, M.D.
Director
Vol. 49 / No. RR-2 MMWR 37
Implementing Recommendations for the
Early Detection of Breast and Cervical Cancer
Among Low-Income Women
Herschel W. Lawson, M.D.
Rosemarie Henson, M.S.S.W., M.P.H.
Janet Kay Bobo, Ph.D., M.S.W.
Mary K. Kaeser, M.Ed.
Division of Cancer Prevention and Control
National Center for Chronic Disease Prevention and Health Promotion
Abstract
Scope of the Problem: Among U.S. women, breast cancer is the most commonly
diagnosed cancer and remains second only to lung cancer as a cause of cancer-related
mortality. The American Cancer Society (ACS) estimates that 182,800 new cases of
female breast cancer and 41,200 deaths from breast cancer will occur in 2000. Since
the 1950s, the incidence of invasive cervical cancer and mortality from this disease
have decreased substantially; much of the decline is attributed to widespread use of the
Papanicolaou (Pap) test. ACS estimates that 12,800 new cases of invasive cervical
cancer will be diagnosed, and 4,600 deaths from this disease will occur in the United
States in 2000.
Etiologic Factors: The risk for breast cancer increases with advancing age; other risk
factors include personal or family history of breast cancer, certain benign breast
diseases, early age at menarche, late age at menopause, white race, nulliparity, and
higher socioeconomic status. Risk factors for cervical cancer include certain human
papilloma virus infections, early age at first intercourse, multiple male sex partners, a
history of sexually transmitted diseases, and low socioeconomic status. Black,
Hispanic, or American Indian racial/ethnic background is considered a risk factor
because cervical cancer detection and death rates are higher among these women.
Recommendations for Prevention: Because studies of the etiology of breast cancer
have failed to identify feasible primary prevention strategies suitable for use in the
general population, reducing mortality from breast cancer through early detection has
become a high priority. The potential for reducing death rates from breast cancer is
contingent on increasing mammography screening rates and subsequently detecting
the disease at an early stage — when more treatment options are available and
survival rates are higher. Effective control of cervical cancer depends primarily on
early detection of precancerous lesions through use of the Papanicolaou test, followed
by timely evaluation and treatment. Thus, the intended outcome of cervical cancer
screening differs from that of breast cancer screening. In 1991, the National Breast and
Cervical Cancer Early Detection Program (NBCCEDP) was implemented to increase
breast and cervical cancer screening among uninsured, low-income women.
Research Agenda: To support recommended priority activities for NBCCEDP, CDC has
developed a research agenda comprising six priorities. These six priorities are
a) determining effective strategies to communicate changes in NBCCEDP policy to
cancer screening providers and women enrolled in the program; b) identifying effective
38 MMWR March 31, 2000
strategies to increase the proportion of enrolled women who complete routine breast
and cervical cancer rescreening according to NBCCEDP policy; c) identifying effective
strategies to increase NBCCEDP enrollment among eligible women who have never
received breast or cervical cancer screening; d) evaluating variations in clinical practice
patterns among providers of NBCCEDP screening services; e) determining optimal
models for providing case-management services to women in NBCCEDP who have an
abnormal screening result, precancerous breast or cervical lesion, or a diagnosis of
cancer; and f) conducting economic analyses to determine costs of providing screening
services in NBCCEDP.
Conclusion: The NBCCEDP, through federal, state, territorial, and tribal governments, in
collaboration with national and community-based organizations, has increased access
to breast and cervical cancer screening among low-income and uninsured women. This
initiative enabled the United States to make substantial progress toward achieving the
Healthy People 2000
objectives for breast and cervical cancer control among racial/
ethnic minorities and persons who are medically underserved. A continuing challenge
for the future is to increase national commitment to providing screening services for all
eligible uninsured women to ultimately reduce morbidity and mortality from breast and
cervical cancer.
INTRODUCTION
Although the causes and natural histories of breast and cervical cancer are different,
the public health responses to these diseases have been similar. Early detection of breast
cancer and primary prevention of cervical cancer are possible through community-based
screening programs; however, early detection of both breast and cervical cancer is less
common among low-income* women (
1
). This report presents morbidity and mortality
data regarding breast and cervical cancer, screening recommendations, an update on
the National Breast and Cervical Cancer Early Detection Program (NBCCEDP), and rec-
ommended priority activities for NBCCEDP. NBCCEDP is a major public health effort to
increase breast and cervical cancer screening among uninsured, low-income women.
SCOPE OF THE PROBLEM
Breast Cancer
Among women in the United States, breast cancer is the most commonly diagnosed
cancer and remains second only to lung cancer as a cause of cancer-related death. The
American Cancer Society (ACS) estimates that 182,800 new cases of female breast
cancer and 41,200 deaths from breast cancer will occur in 2000 (
2
). In 1996, data from
the National Cancer Institute’s (NCI) Surveillance, Epidemiology, and End Results (SEER)
Program
†
indicated that the incidence of breast cancer increased 25.3% during
*Defined as up to 250% of poverty level depending, on family size.
†
In 1996, the SEER program comprised cases from 11 population-based cancer registries
throughout the United States that represent an estimated 13.9% of the U.S. population. The
SEER program also publishes death rates based on a public-use data tape from CDC’s
National Center for Health Statistics. During 1988–1996, the 11 locations were Connecticut;
Hawaii; Iowa; New Mexico; Utah; and Atlanta, Detroit, San Francisco/Oakland, San Jose/
Monterey, Los Angeles, and Seattle/Puget Sound.
Vol. 49 / No. RR-2 MMWR 39
1973–1996 (Figure 1). Most of the increase occurred during 1973–1991; incidence rates
remained stable during 1992–1996. In 1996, the incidence rate for breast cancer was
110.7 cases per 100,000 women, a 29.6% increase since 1980. In addition, in 1996, the
case-fatality rate for breast cancer was 24.3 per 100,000 women, a 4.5% decrease since
1992, representing the first sustained decline in breast cancer-related mortality since
1973 (when SEER surveillance for breast cancer began). Although the percentage in-
creases in incidence during 1973–1996 were similar among black and white women, the
percentage decrease in mortality during 1992–1996 was substantially greater among
white women than black women (
3,4
).
Overall during 1992–1996, breast cancer incidence rates were higher among white
women (113.1 per 100,000) than black women (100.3), but breast cancer death rates
were lower among white women (25.1) than black women (32.0). Furthermore, these
race-specific differences in rates varied by age. Among women aged <50 years, the
incidence rate for black women (32.7) was higher than that for white women (31.1).
Among women aged ³50 years, the rate was higher for white women (365.8) than for
black women (308.7). The death rate among women aged <65 years was higher for black
women (20.4) than for white women (14.3). Although the death rate among women aged
³65 years was higher for white women than for black women before 1987, recent data
indicate that the death rate among this age group is higher for black women (130.9) than
for white women (124.0) (
4,5
). On the basis of SEER data for 1988–1992 (most recent
data available), incidence rates were highest for white (145.7), Hawaiian (105.6), and
black women (95.4) and lowest for Korean (28.5), American Indian (31.6), and Vietnam-
ese (37.5) women. Incidence rates among white, non-Hispanic women were four times
higher than among Korean women (
3
).
FIGURE 1. Incidence rate* and death rate
†
of invasive breast cancer, by year — United
States, 1973–1996
*Per 100,000 women; age-adjusted to 1970 U.S. population. Calculated using Surveillance,
Epidemiology, and End Results (SEER) data.
†
Per 100,000 women; age-adjusted to 1970 U.S. population. Calculated using national mortality
data from CDC's National Center for Health Statistics.
Source: SEER Cancer Statistics Review, 1973–1996.
1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995
Year
0
20
40
60
80
100
120
Rate
Rate
I
nc
id
ence
Death
40 MMWR March 31, 2000
Stage-specific survival rates among women with breast cancer have increased
slightly since the 1970s (
6
). The overall 5-year survival rates for women during 1989–95
were 86% for white women and 71% for black women (
4
). Survival was greatest at the
earliest stage of disease. Age-specific survival rates were similar for white and black
women. One explanation for the disparity in race-specific survival rates is that white
women, on average, seek medical care for tumors at an earlier stage of disease than
black women. However, the interim between symptom recognition and medical consul-
tation does not appear to account for these race-specific differences in survival rates or
stage at diagnosis of breast cancer (
6
). Limited data are available regarding survival for
other ethnic groups in the United States. In a study of stage at diagnosis and tumor
histology among white and Asian women, the 5-year survival rate at all stages was
higher among Asian women than among white women (
7
). In addition, based on data
from another study, the survival rate among Hispanic women is similar to the rate among
white women in the United States (
8
).
Cervical Cancer
Since the 1950s, the incidence of invasive cervical cancer and mortality from this
disease have decreased substantially. In large part, the decline has been attributed to
widespread use of the Papanicolaou (Pap) test — a highly effective preventive measure.
However, the rate of decline in invasive cervical cancer has slowed since the early 1980s
and appears to have stabilized in recent years (Figure 2). ACS projects that approxi-
mately 12,800 cases of invasive cervical cancer will be diagnosed and that approxi-
*Per 100,000 women; age-adjusted to 1970 U.S. population. Calculated using Surveillance,
Epidemiology, and End Results (SEER) data.
†
Per 100,000 women; age-adjusted to 1970 U.S. population. Calculated using national mortality
data from CDC's National Center for Health Statistics.
Source: SEER Cancer Statistics Review, 1973–1996.
FIGURE 2. Incidence rate* and death rate
†
of invasive cervical cancer, by year — United
States, 1973–1996
1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995
Y
ear
0
2
4
6
8
10
12
14
16
Rate
Rate
I
nc
id
ence
Death
Vol. 49 / No. RR-2 MMWR 41
mately 4,600 cervical cancer deaths will occur in the United States in 2000 (
2
). During
1992–1996, the incidence rate at SEER sites was 7.9 cases per 100,000 women, and the
death rate for cervical cancer was 2.8 per 100,000 women (
4
).
On the basis of SEER data, both incidence and death rates for cervical cancer vary
among racial/ethnic groups. The incidence rate for cervical cancer is highest among
Vietnamese women (43.0), and the death rate for cervical cancer is highest among black
women (6.7) (
3
). The incidence rate among black women (11.2 per 100,000) is approxi-
mately 50% higher than among white women (7.3) (
3,4
). Death rates among black
women (5.9) are approximately twice as high as those among white women (2.4). Al-
though the disparities in rates between blacks and whites have declined since 1990,
differences in rates persist. This persistent disparity has been attributed to several fac-
tors, including differences in the prevalence of risk factors for cervical cancer; differ-
ences in screening, diagnostic evaluation, and treatment; and differences in the stage
of disease at diagnosis (
9
).
Race-specific differences in incidence and death rates for cervical cancer also varied
by age (
4
). During 1992–1996, among women aged <35 years, the rate of invasive
cervical cancer among black women was lower than the rate among white women.
However, in older age groups, incidence rates among white women fluctuated between
13 and 15 per 100,000 women, whereas rates among black women tended to increase
with age to approximately 32 per 100,000 for those aged ³75 years. Among both black
and white women, death rates for cervical cancer increased with advancing age; how-
ever, rates were substantially higher for black women aged >40 years than for white
women the same age. Regardless of race, most cervical cancer deaths occur among
women aged ³50 years (
4
).
For women in whom invasive but localized (i.e., Stage I) cervical cancer has been
diagnosed, the 5-year relative survival rate is approximately 90% (
4
). In contrast, for
women with advanced invasive cervical cancer (beyond the cervix and pelvis [i.e., Stage
III and IV, respectively]), the 5-year relative survival rate is approximately 12%. As with
breast cancer, diagnosis of invasive cervical cancer in black women usually occurs at a
later stage of disease compared with white women. Moreover, 5-year relative survival
rates for local and regional stages are lower for blacks than for whites.
ETIOLOGIC FACTORS
Breast Cancer
The risk for breast cancer increases with advancing age. Other risk factors include
personal or family history of breast cancer, history of certain benign breast diseases,
early age at menarche, late age at menopause, exposure to ionizing radiation, obesity,
white race, nulliparity, late age at first birth, nodular densities on mammogram, higher
socioeconomic status, and residence in urban areas of the northern United States (
6,10
).
Less clearly established risk factors include the duration between menstrual periods,
use of oral contraceptives, use of replacement hormones (estrogen), height, alcohol
consumption, and not breast-feeding.
Studies of immigrants to the United States suggest that environmental factors rather
than genetic factors are responsible for variations in breast cancer rates among coun-
tries. For example, the rate of breast cancer among first-generation Japanese-American
42 MMWR March 31, 2000
women is only slightly higher than the rate among their mothers, but the rate among
their daughters is considerably higher (
6
).
No primary prevention measures suitable for use in the general population have
been established for breast cancer. Preliminary results from clinical trials among high-
risk women regarding the use of the drug tamoxifen indicate a 45% decline in incidence
from its use (
11
). Although side effects and potential development of other neoplasms
are associated with tamoxifen use, other medications in its class might offer even greater
benefits in breast cancer treatment. The Study of Tamoxifen and Raloxifene (STAR) trial
is under way to evaluate tamoxifen versus raloxifene and the potential for reducing the
incidence of breast cancer in high-risk postmenopausal women.
Cervical Cancer
The risk for cancer of the cervix has been associated with several factors, including
infection with certain types of human papilloma virus (HPV), early age at first inter-
course, multiple male sex partners, a history of sexually transmitted diseases, smok-
ing, certain nutritional deficiencies, and low socioeconomic status (
12
). HPV is widely
accepted as the cause of most squamous cell cervical cancers, and the sexual practices
listed are well-established risk factors for the disease; however, the role of other demo-
graphic and behavioral factors is less clear. Black, Hispanic, or American Indian race/
ethnicity is considered a risk factor for cervical cancer because rates of detection and
death from cervical cancer are higher among these women (
13
). However, some of the
racial/ethnic differences in cervical cancer rates can be explained by the strong inverse
association between socioeconomic indicators and the risk for invasive cervical cancer
(
13
). This increased risk could be associated with differences in access to care and
cultural behavior.
RECOMMENDATIONS FOR PREVENTION
Breast Cancer
Studies of the etiology of breast cancer have failed to identify feasible primary pre-
vention strategies suitable for use in the general population. Many established risk
factors for the disease are neither environmental nor behavioral and, therefore, are not
amenable to prevention. Most of the hypothesized behavioral factors are not fully ac-
cepted as risk factors and are typically difficult to alter at the individual level. For these
reasons, reducing mortality from breast cancer through early detection has become a
high priority. The potential for reducing death rates from breast cancer is contingent on
increasing initial and repeat mammography screening rates and subsequently detecting
the disease at an early stage — when more treatment options are available, and survival
rates are higher.
Mammography is the most effective method of detecting breast cancer in its earli-
est and most treatable stage (
14
). Mammography is a low-dose X-ray procedure that
visualizes the internal structure of the breast to detect cancers too small to be palpated
during a clinical breast examination (CBE) performed by a health-care provider. Mam-
mography detects cancer before the woman can palpate the lump herself. Cancers
Vol. 49 / No. RR-2 MMWR 43
detected at a small size are more likely to be localized (i.e., not spread to regional lymph
nodes or distant body sites).
The sensitivity of mammography (75%–94%) is higher than comparable values for
CBE alone or breast self-examination (
14,15
).
The specificity of mammography (i.e., the
likelihood that a mammogram will correctly indicate that breast cancer is not present) is
also high (83%–98%) (
14,15
). Widespread use of this procedure, alone or with a CBE
performed by a trained health-care provider, can reduce overall mortality from breast
cancer (
14,16
). Since the 1970s, scientific studies have demonstrated that regular screen-
ing mammograms among women aged 50–69 years can reduce mortality from breast
cancer by 30% (
14,17–19
). However, evidence is not as conclusive for women aged 40–
49 years and ³70 years (
14
).
The ability of mammography to identify breast cancer at an early stage improves the
opportunity for effective treatment and survival. Women in whom localized/Stage I dis-
ease has been diagnosed have a 5-year relative survival rate of 94% (
4
). In comparison,
women with disease spread beyond regional lymph nodes have a 5-year relative sur-
vival rate of only 18.2%. Treatment at this late stage is substantially less effective, as well
as more debilitating.
Breast Cancer Screening Guidelines Recommended by Various Groups
Annual breast cancer screening for women aged ³50 years is widely recommended.
In addition, screening is recommended for women aged 40–49 years; however, consen-
sus has not been reached regarding the effectiveness of screening or the optimal inter-
val for screening in this age group (
20
). Several review groups have reached different
conclusions about the efficacy of mammography among younger women because of
the limitations of studies conducted among women in this age group. These limitations
include small sample sizes and limited duration of follow-up after entry into the screen-
ing programs (
21
).
In 1996, the U.S. Preventive Services Task Force (USPSTF) recommended that
women aged 50–69 years receive routine breast cancer screening every 1–2 years
using mammography alone or mammography combined with annual CBE (
14
). USPSTF
noted that insufficient evidence exists to recommend or not recommend routine mam-
mography or CBE for women aged 40–49 years and ³70 years. Moreover, insufficient
evidence exists to recommend CBE alone or teaching breast self-examination. In addi-
tion, USPSTF noted that recommendations for mammography among high-risk women
aged 40–49 years and among healthy women aged ³70 years might be made on other
grounds.
In 1997, a National Institutes of Health Consensus Development Conference panel
reviewed new data not previously available to USPSTF, which documented mortality
benefit from mammography among women aged 40–49 years (
22
). However, the panel
concluded that these data did not warrant a universal recommendation for mammogra-
phy for women aged 40–49 years. As a result, the panel encourages these women to
determine for themselves whether to receive mammography on the basis of objective
analysis of scientific evidence, individual health history, and perceived risks and bene-
fits (
20
).
Because mortality can be reduced among women aged 40–49 years, in 1997 the
National Cancer Institute (NCI) accepted new guidelines for mammography screening
recommended by the presidentially appointed National Cancer Advisory Board. These
44 MMWR March 31, 2000
guidelines recommend that all women aged ³40 years receive mammography every
1–2 years to achieve the best possible outcome if breast cancer is detected (
22
).
Prevalence of Breast Cancer Screening
Data collected through CDC’s 1997 Behavioral Risk Factor Surveillance System
(BRFSS) indicate that 85% of all interviewed women aged ³40 years had ever received
a mammogram (
23
). The percentage of low-income women and women without health
insurance who had ever received a mammogram was comparable (77% and 69%, re-
spectively). The percentage of all interviewed women aged ³40 years who had received
a mammogram within the preceding 2 years was 71%. Rates for low-income women and
women without health insurance were substantially lower (58% and 50%, respectively).
A
Healthy People 2000
objective is to increase to at least 80% the proportion of
women aged ³40 years who have ever received a CBE and a mammogram, and to at
least 60% those aged ³50 years who have received them within the preceding 1–2 years
(objective 16.11) (
24
). Although 1997 BRFSS data indicate the goal has been attained for
all women interviewed aged ³40 years who had ever received a mammogram, progress
is still needed to attain the goal for low-income women and women without health insur-
ance.
Cervical Cancer
Effective control of cervical cancer depends primarily on early detection of precan-
cerous lesions through use of the Pap test, followed by timely evaluation and treat-
ment. The Pap test is probably the most successful screening test ever developed to
detect a cancer. Although the efficacy of cervical cancer screening using the Pap test
has not been evaluated in clinical trials, at least two factors support the positive impact
of this screening test: a) evidence from many observational studies and b) the marked
decline in cervical cancer incidence and death rates in the United States and other
countries since the introduction of the Pap test >40 years ago (
14,25
).
In the United States, approximately 50 million Pap tests are performed annually
(
26
). Approximately 10% of these tests indicate an abnormality requiring further testing.
Detection and treatment of precancerous cervical intraepithelial neoplasia (CIN) lesions
identified by the Pap test can prevent cervical cancer. Thus, the intended outcome of
cervical cancer screening differs from breast cancer screening. The primary goal of
cervical cancer screening is to detect and treat CIN to prevent the occurrence of invasive
cancer. For women in whom CIN lesions have been detected, the likelihood of survival is
nearly 100% with appropriate evaluation, treatment, and follow-up.
Cervical Cancer Screening Guidelines Recommended by Various Groups
The American College of Obstetricians and Gynecologists (ACOG) and ACS recom-
mend that women have a Pap test and pelvic examination when they become sexually
active or at age 18 years, whichever occurs first (
13
). Annual Pap tests are recom-
mended until three consecutive Pap tests are interpreted as being normal. Following
this, the two groups recommend that Pap tests can be performed less frequently at the
discretion of the provider (
13
).
In 1996, USPSTF recommended routine screening for women who are or who have
been sexually active and who have a uterine cervix (
14
). The task force recommends
Pap tests with the onset of sexual activity and repeated screening every 3 years. A
Vol. 49 / No. RR-2 MMWR 45
reduced interval between screenings can be recommended by the physician on the
basis of a woman’s risk factors for cervical cancer. In addition, USPSTF recommends
that, on the basis of existing evidence, Pap screening might not be necessary for women
after age 65 years. Moreover, USPSTF recommended not performing Pap tests on
women who have undergone total hysterectomies for diseases unrelated to cervical
cancer or its precursors (
14
).
In recent years, several studies have been conducted to determine the value of
expanding HPV testing from testing only women with abnormal Pap test results to rou-
tinely testing all women to detect those women at greatest risk for developing CIN or
invasive cervical cancer. Evidence from these studies does not support routine HPV
testing to screen for cervical cancer (
26
). Although new cervical cancer screening tech-
nologies have been approved for primary screening, professional organizations have
not endorsed their widespread use because of concerns about cost effectiveness.
An increasing concern is that rescreening the same women annually will not result
in further reductions in cervical cancer mortality (
27
). Increased effort is needed to
target groups with large proportions of unscreened or rarely screened women, includ-
ing women residing in rural areas; minorities; and recent immigrants who have differ-
ent attitudes, knowledge, and behaviors regarding disease prevention and health pro-
motion. Screening for cervical cancer among these women could further reduce the
burden of disease from cervical cancer.
Prevalence of Cervical Cancer Screening
The 1997 BRFSS documented that 93% of women aged ³18 years with a uterine
cervix reported ever having received a Pap test (
23
). Corresponding values for low-
income and uninsured women were 89% and 85%, respectively. Among all women
with a uterine cervix, 80% had obtained a Pap test within the preceding 2 years. For
low-income women and uninsured women, the proportion who had obtained a Pap test
was substantially lower (69% and 65%, respectively).
A
Healthy People 2000
objective is to increase to at least 95% the proportion of
women aged ³18 years with a uterine cervix who have ever received a Pap test, and to
at least 85% those who have received a Pap test within the preceding 1–3 years (objec-
tive 16.12) (
24
). Although 1997 BRFSS data indicate the goal for women aged ³18 years
with a uterine cervix who reported ever having received a Pap test is near attainment,
progress is still needed, as with breast cancer screening, to attain the goal for low-
income women and women without health insurance.
Low income and lack of health insurance are barriers to both cervical and breast
cancer screening. These factors increase the likelihood that these diseases will be diag-
nosed at a later stage, when survival rates are lower (
1
).
Implementation of the National Breast and Cervical Cancer
Early Detection Program
In August 1990, Congress enacted the Breast and Cervical Cancer Mortality Preven-
tion Act, thereby authorizing CDC to establish a national public health infrastructure to
increase breast and cervical cancer screening among low-income women who are unin-
sured (
28
). Consequently, CDC established the National Breast and Cervical Cancer
Early Detection Program (NBCCEDP), a comprehensive women’s health initiative imple-
46 MMWR March 31, 2000
mented through cooperative agreements with qualifying health agencies (including state
and territorial health departments and American Indian/Alaska Native tribes and tribal
organizations). In addition to providing breast and cervical cancer screening, participat-
ing programs provide diagnostic testing, surveillance and follow-up, case management,
public education and outreach, professional education and training, quality assurance of
screening tests, coalition and partnership development, and program evaluation.
NBCCEDP-sponsored programs have initiated outreach efforts to serve women in high
priority groups (e.g., women with increased risk for breast or cervical cancer and women
who do not or rarely access breast and cervical cancer screening), including older women,
racial/ethnic minorities, foreign-born women, women with disabilities, lesbians, and
women residing in rural or other hard-to-reach areas.
Fiscal year (FY) 2000 marked the 10th year of the NBCCEDP, with Congressional
appropriations of $167 million. CDC provides funds to all 50 states, six U.S. territories,
the District of Columbia, and 15 American Indian/Alaska Native tribes and tribal organi-
zations to implement comprehensive screening programs for breast and cervical can-
cer (
29
).
During the reporting period July 1991–March 1999, approximately 2.2 million screen-
ings for breast and cervical cancer were provided to uninsured women. The program
supported 1,049,752 mammograms: 64% of the mammograms were provided to women
aged ³50 years; 48% were provided to racial/ethnic minorities (Figure 3). Breast cancer
was diagnosed in 6,265 women aged ³40 years. Although the rate of abnormalities
detected by a mammogram was highest for younger women, the rate of breast cancers
detected per 100,000 mammograms increased directly with advancing age (Figure 4). A
total of 1,192,346 Pap tests were performed: 72% of the tests were provided to women
FIGURE 3. Percentage distribution of program participants* who received screening
mammograms, by race/ethnicity
†
and age group — United States, National Breast and
Cervical Cancer Early Detection Program, July 1991–March 1999
*n = 676,474.
†
Persons of Hispanic origin can be of any race.
White
52%
Hispanic
19%
Black
17%
American Indian
6%
Asian
4%
Other/Unknown
2%
By Race/Ethnicity
<40
4%
40–49
32%
50–64
51%
65–74
9%
>75
4%
By Age
G
roup (Years)
Vol. 49 / No. RR-2 MMWR 47
aged ³40 years; 47% were provided to racial/ethnic minorities (Figure 5). Cervical
intraepithelial neoplasia was detected in 34,046 women. Invasive cervical cancer was
diagnosed in 561 women. The rate of abnormal Pap tests varied inversely with age.
Policy of NBCCEDP
As NBCCEDP has evolved, the program has addressed many challenges, especially
regarding screening recommendations and treatment resources for women in whom
precancerous cervical lesions or cancer of the breast or cervix has been diagnosed
through NBCCEDP. FY 2000 Congressional appropriations will enable NBCCEDP to screen
approximately 12%–15% of the eligible uninsured women aged 50–64 years in the United
States (
30
). The remaining unmet need and the absence of funding to cover treatment
expenses for women who have received a diagnosis of precancerous cervical lesions or
breast or cervical cancer have been persistent challenges to the program. A key public
health priority of NBCCEDP is to direct program resources to eligible women who have
rarely or have never received breast or cervical cancer screening. To address this prior-
ity and maximize efficient use of limited resources, the program has developed cancer-
control policies on the basis of programmatic data, current scientific research, and
availability of screening services through other government-supported programs (e.g.,
Medicare and Title X Family Planning programs).
Breast Cancer Screening Policies
Following implementation of NBCCEDP in 1991, CDC encouraged NBCCEDP-
sponsored programs to place a high priority on screening women aged ³50 years.
FIGURE 4. Rate* of breast cancer, by age group, and overall rate
†
— United States,
National Breast and Cervical Cancer Early Detection Program, July 1991–March 1999
*Per 100,000 mammograms.
†
Per 100,000 mammograms; age-adjusted to the 1970 U.S. population.
40-49 50-64 65-74
>
75
>40
A
ge
G
roup
(Y
ears
)
0
200
400
600
800
1000
Rate
In situ Breast Cancer
Invasive Breast Cancer
479.4
587.4
637.8
803.4
575.3
48 MMWR March 31, 2000
NBCCEDP data indicated that only 57% of their mammograms were provided to women
aged ³50 years. In October 1994, CDC established the first age-specific targets for the
breast cancer screening component of NBCCEDP. For 1995, 75% of the mammograms
were to be provided to women aged ³50 years. The percentage was gradually increased
to 90% by October 1998. A review of NBCCEDP mammography screening data in 12-
month intervals indicated that, since 1994, programs had screened increasing numbers
of women aged ³50 years for breast cancer; however, the age-specific percentage goals
had not been attained. For example, the percentage of initial mammograms provided to
women aged ³50 years for the reporting period October 1996–September 1997
was 74%.
In 1998, NBCCEDP mammogram screening policy was revised in response to new
scientific research, recent changes in recommendations by NCI and ACS, changes in
Medicare preventive services coverage, and the need to establish a more realistic na-
tional target based on historical programmatic screening data. The new NBCCEDP policy
is to provide at least 75% of mammograms to women aged ³50 years who are not
eligible to receive Medicare Part B benefits or are unable to pay the premium to enroll in
Medicare Part B. Correspondingly, no more than 25% of mammograms should be pro-
vided to women aged <50 years. As a result of this new policy, some participating health
agencies have developed strategies to cover breast cancer screening for women aged
40–49 years. Several programs have obtained breast cancer screening resources for
these women from state appropriations or tobacco tax revenues and through collabora-
tive efforts with foundations (e.g., the Susan G. Komen Breast Cancer Foundation). Dur-
ing October 1997–September 1998, 75% of NBCCEDP-sponsored mammograms were
provided to women aged ³50 years.
FIGURE 5. Percentage distribution of program participants* who received Papanicolaou
tests, by race/ethnicity
†
and age group — United States, National Breast and Cervical
Cancer Early Detection Program, July 1991–March 1999
*n = 761,822.
†
Persons of Hispanic origin can be of any race.
White
53%
Hispanic
20%
Black
15%
American Indian
7%
Asian
3%
Other/Unknown
2%
B
y
R
ace
/E
t
h
n
i
c
i
ty
<30
14
%
30–39
14%
40–49
29%
50–64
35%
65–74
8%
B
y
A
ge
G
roup
(Y
ears
)
Vol. 49 / No. RR-2 MMWR 49
Cervical Cancer Screening Policies
The primary purpose of the cervical cancer component of NBCCEDP is to identify and
treat precancerous cervical lesions and to detect and treat invasive cervical cancer at an
early stage. When the program was established in 1991, CDC implemented program
guidelines for cervical cancer screening that were consistent with ACS guidelines.
Women enrolled in NBCCEDP who were aged ³18 years, with an intact uterine cervix,
were eligible for an annual Pap test and pelvic examination. After a woman has had
three consecutive annual examinations with normal findings, Pap tests could be per-
formed less frequently at the discretion of the woman and her health-care provider.
In 1999, CDC, in consultation with an external work group comprising clinical experts,
epidemiologists, and public health practitioners, reexamined NBCCEDP’s cervical can-
cer screening policy and other emerging issues related to Pap testing. One of the key
issues addressed by this work group was recommendations for Pap screening intervals.
ACOG’s and ACS’s recommendations regarding the frequency of screening are simi-
lar and advise that after a woman has had three consecutive annual examinations with
normal findings, the Pap test can be performed less frequently at the discretion of the
woman’s provider. Scientific data suggest that once a woman has demonstrated no
signs of CIN, as evidenced by three consecutive annual Pap tests with normal findings,
her chance of developing CIN II or worse within a 3-year period is extremely low, regard-
less of other risk factors (
31
). Preliminary analysis of NBCCEDP data supports these
findings (CDC, unpublished data, 2000).
Beginning in March 2000, NBCCEDP-sponsored programs will be required to direct
more cervical cancer screening resources to women who have never had a Pap test or
who have not had a Pap test for at least 5 years. Among all women screened, at least
20% should be women who have either never been screened or have rarely been
screened (i.e., not screened for ³5 years). Programs are also being required to reduce
over-screening among program-enrolled women. Beginning in October 2001, programs
will be required to document that at least 75% of women with three consecutive annual
Pap tests with normal findings did not receive a fourth annual Pap test. Their screening
interval will be changed to every 3 years. To successfully implement this policy change,
CDC will assist NBCCEDP-sponsored programs in assessing current program provider
practices, modifying patient recall systems, and developing professional and public edu-
cation strategies.
Breast and Cervical Cancer Follow-Up and Treatment Policy
The policy issue that has caused the greatest controversy in NBCCEDP concerns the
availability of funds to pay for treatment of cancerous or precancerous lesions diag-
nosed in enrolled women (
28
). A crucial component of NBCCEDP is to ensure that all
women with abnormal screening results, precancerous breast or cervical lesions, or a
diagnosis of cancer receive timely and appropriate follow-up care. Program providers
receive reimbursement for most diagnostic procedures, including diagnostic mammog-
raphy, breast ultrasound, fine-needle aspiration of the breast, breast and cervical biop-
sies, and colposcopy of the cervix. However, the Breast and Cervical Cancer Mortality
Prevention Act of 1990 prohibits use of federal program funds for any component of
breast or cervical cancer treatment primarily because of a concern that such payment
would rapidly deplete resources available for screening services. NBCCEDP-sponsored
programs are required to identify and secure resources for treatment from other sources.
50 MMWR March 31, 2000
In 1996, CDC conducted in-depth case studies of seven state programs to determine
how early detection programs identified and obtained resources for treatment. The re-
sults indicated that state health agencies and their partners had developed a wide range
of strategies for procuring treatment services in the absence of program resources.
However, the study respondents considered the strategies used to obtain these services
as short-term solutions that were labor intensive and that diverted resources away from
screening activities (
32
).
NBCCEDP surveillance data for October 1991–September 1998 indicate that 92% of
the clients in whom breast cancer had been diagnosed and 93% of the clients in whom
invasive cervical cancer had been diagnosed initiated treatment. The remainder either
refused treatment, were lost to follow-up, or had an outcome pending. In FY 1999, CDC
received increased Congressional appropriations to expand case-management activi-
ties to assist women in overcoming financial, logistical, and other barriers to obtaining
these services.
Recommended Priority Activities for CDC
The Breast and Cervical Cancer Mortality Prevention Act of 1990 has played an
important role in focusing public health efforts on cancer control in the United States.
Since 1991, CDC has collaborated with a diverse group of public and private partners to
build the public health infrastructure, implement screening services, and conduct re-
search activities. CDC will continue to foster these relationships to achieve goals set in
the following four priority areas of screening initiatives, case-management services,
professional education and training, and partnerships:
Screening Initiatives
• Collaborate with NBCCEDP-sponsored programs to increase public education and
outreach strategies to reach women who have rarely or have never received
breast or cervical cancer screening.
• Collaborate with NBCCEDP-sponsored programs to implement strategies among
health-care providers to address missed opportunities for enrolling women into
screening.
• Collaborate with NBCCEDP-sponsored programs to implement strategies
through professional groups and public education to modify screening intervals
for all program-enrolled women who have had three consecutive annual Pap
tests with normal findings.
• Continue to promote the need for routine rescreening for breast and cervical
cancer at regular intervals to improve rescreening rates for women enrolled in
NBCCEDP.
Case-Management Services
• Expand case-management activities to ensure that women enrolled in NBCCEDP
receive timely and appropriate rescreening and diagnostic services and
treatment services, if indicated.
• Increase case-management activities to sustain networks and partnerships to
maximize access to and availability of diagnostic, treatment, and essential
support services for women enrolled in NBCCEDP.
Vol. 49 / No. RR-2 MMWR 51
Professional Education and Training
• Increase collaboration with professional groups that provide continuing
education for their constituents to address breast and cervical cancer control
issues in standardized curricula and training.
• Continue to advocate for incorporation of breast and cervical cancer education in
curricula for health professionals to facilitate a long-term effect on provider
practice.
Partnerships
• Continue to build partnerships with public health departments, tribes and tribal
organizations, national and voluntary organizations, academic centers, and
health-care purchasers through the following activities: implementing strategies
communitywide to promote awareness and screening practices among all
women; replicating and disseminating programmatic approaches that are
proven effective in providing screening to priority populations (e.g., racial/ethnic
minorities and women residing in rural or other hard-to-reach areas);
cosponsoring conferences, workshops, and training related to breast and
cervical cancer issues; and advocating for breast and cervical cancer control
priorities (e.g., policies and standards) to ensure the quality of mammography
and Pap screening delivered by all providers.
RESEARCH AGENDA
To support the recommended priority activities for NBCCEDP, CDC has developed a
research agenda comprising six priorities. This research will assist in improving cancer
screening services provided to women enrolled in NBCCEDP and in developing new
methods to recruit eligible women who have rarely or have never received breast or
cervical cancer screening.
•
Priority: Determine effective strategies to communicate changes in NBCCEDP
policy to cancer screening providers and women enrolled in the program.
Emerging developments in cancer prevention and control occasionally require
substantial changes in program policy (e.g., changing from annual to triennial
cervical cancer screening among women with three previous normal Pap tests).
Changes in program policy might require adapting the practice patterns of
providers and modifying the expectations and behaviors of enrolled women.
Research is needed to develop and evaluate effective public and provider
education and materials for dissemination that will help translate policy changes
into practice as rapidly as possible.
•
Priority: Identify effective strategies to increase the proportion of enrolled
women who complete routine breast and cervical cancer rescreening according
to NBCCEDP policy.
Available data submitted twice a year to CDC by participating
programs suggest that many women enrolled in NBCCEDP, regardless of their
race/ethnicity, do not complete routine rescreening on schedule. Some research
is under way in this area, but more is needed. A multiethnic, multicultural focus
group study of the barriers to mammography rescreening among NBCCEDP
52 MMWR March 31, 2000
enrollees in Texas (
33
) resulted in development of an ongoing retrospective
cohort investigation among 2,500 randomly selected enrollees in Maryland, New
York, Ohio, and Texas. Findings from this research that identify risk factors for
failure to rescreen on schedule will be used to develop and test new interventions
to increase routine rescreening; however, additional research is needed in this
area.
•
Priority: Identify effective strategies to increase NBCCEDP enrollment among
eligible women who have never received breast or cervical cancer screening.
Data from the 1997 BRFSS suggest that substantial numbers of age-eligible, low-
income women have never received mammography or Pap smear screening
(
23
). To develop effective outreach and enrollment strategies for women who
have rarely or have never received cancer screening, participatory research
methods that involve unscreened women and members of their communities in
all phases of the research process might be particularly valuable. In addition,
quantitative research designs might be necessary to test proposed interventions.
Research initiatives related to this priority topic must address both missed
screening opportunities in diverse provider settings and various cultural,
language, and institutional barriers that might influence a woman’s willingness to
accept free or low-cost cancer screening when offered.
•
Priority: Evaluate variations in clinical practice patterns among providers of
NBCCEDP screening services.
Analyses of data submitted every 6 months to CDC
by participating programs have identified several practice patterns that differ
markedly across these programs. These variations raise concern regarding
quality assessment. For example, an analysis of mammography results for 1991–
1996 reported through the Breast Imaging Reporting and Data System (BI-
RADS
®
) lexicon developed by the American College of Radiology (
34
)
documented that the proportion of mammograms coded “probably benign, short-
term follow-up recommended” varied substantially across the state, territorial,
and tribal programs (
35
). To understand the reasons for such variations and to
develop appropriate provider education materials, where necessary, case
studies and record linkage investigations within collaborating programs might be
necessary. Such studies must be conducted within participating programs
because data submitted to CDC cannot be linked with medical records, pathology
laboratory reports, or cancer registries.
•
Priority: Determine optimal models for providing case-management services to
women in NBCCEDP who have an abnormal screening result or a diagnosis of
cancer.
Without effective case management, some low-income women who need
additional cancer testing or treatment will not receive the necessary care or will
not receive it as rapidly as possible. Diverse case-management models have
been developed for other public health concerns including tuberculosis control,
adolescent prenatal care, and human immunodeficiency virus infection/acquired
immunodeficiency syndrome. Research is needed to evaluate the applicability of
these and other models to low-income, medically uninsured women who need
additional cancer testing and treatment. Critical issues include determining how
women will be selected for case management, how extensive case-management
Vol. 49 / No. RR-2 MMWR 53
efforts should be, and what proportion of screening resources should be allocated
to case-management activities.
•
Priority: Conduct economic analyses to determine costs of providing screening
services in NBCCEDP.
Because the funds appropriated by Congress to NBCCEDP
are not adequate to screen all eligible women who need breast and cervical
cancer screening, economic analyses are necessary to enhance efficient use of
the available resources. Important issues include the potential cost advantages of
high-volume versus low-volume laboratories and mammography facilities, the
sustainability of facilities that are providing program-funded screenings below
their current cost levels, and the costs and benefits of mammography vans
compared with standard facilities.
CONCLUSION
Breast and cervical cancer continue to be major health problems in the United States.
Preventive measures are available to reduce morbidity and mortality associated with
these diseases. The NBCCEDP, through federal, state, territorial, and tribal governments,
in collaboration with national and community-based organizations, has increased access
to breast and cervical cancer screening among low-income and uninsured women. In
addition, NBCCEDP-sponsored programs have increased the staff working in cancer
control and the expertise of these persons, implemented professional education pro-
grams for health-care providers, and developed innovative public education and out-
reach strategies to encourage medically underserved women to seek screening ser-
vices. This national effort enabled the United States to make substantial progress to-
ward achieving the
Healthy People 2000
objectives for breast and cervical cancer con-
trol, particularly among racial/ethnic minorities and the medically underserved. How-
ever, NBCCEDP still reaches only 12%–15% of uninsured women aged 50–64 years who
are eligible for screening services. A continuing challenge for the future is to increase
national commitment to providing screening services for all eligible uninsured women to
ultimately reduce morbidity and mortality from breast and cervical cancer.
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Vol. 49 / No. RR-2 MMWR 57
Preventing Congenital Toxoplasmosis
58 MMWR March 31, 2000
The material in this report was prepared for publication by:
National Center for Infectious Diseases ................................. James M. Hughes, M.D.
Director
Division of Parasitic Diseases ................................................. Daniel G. Colley, Ph.D.
Director
Vol. 49 / No. RR-2 MMWR 59
Preventing Congenital Toxoplasmosis
Adriana Lopez, M.H.S.
Vance J. Dietz, M.D.
Marianna Wilson, M.S.
Thomas R. Navin, M.D.
Jeffrey L. Jones, M.D., M.P.H.
Division of Parasitic Diseases
National Center for Infectious Diseases
Abstract
Scope of the Problem: Toxoplasmosis is caused by infection with the protozoan parasite
Toxoplasma gondii
. Acute infections in pregnant women can be transmitted to the fetus
and cause severe illness (e.g., mental retardation, blindness, and epilepsy). An
estimated 400–4,000 cases of congenital toxoplasmosis occur each year in the United
States. Of the 750 deaths attributed to toxoplasmosis each year, 375 (50%) are
believed to be caused by eating contaminated meat, making toxoplasmosis the third
leading cause of foodborne deaths in this country.
Etiologic Factors:
Toxoplasma
can be transmitted to humans by three principal routes:
a) ingestion of raw or inadequately cooked infected meat; b) ingestion of oocysts, an
environmentally resistant form of the organism that cats pass in their feces, with
exposure of humans occurring through exposure to cat litter or soil (e.g., from
gardening or unwashed fruits or vegetables); and c) a newly infected pregnant woman
passing the infection to her unborn fetus.
Recommendations for Prevention:
Toxoplasma
infection can be prevented in large part
by a) cooking meat to a safe temperature (i.e., one sufficient to kill
Toxoplasma
);
b) peeling or thoroughly washing fruits and vegetables before eating; c) cleaning
cooking surfaces and utensils after they have contacted raw meat, poultry, seafood, or
unwashed fruits or vegetables; d) pregnant women avoiding changing cat litter or, if no
one else is available to change the cat litter, using gloves, then washing hands
thoroughly; and e) not feeding raw or undercooked meat to cats and keeping cats inside
to prevent acquisition of
Toxoplasma
by eating infected prey.
Research Agenda: Priorities for research were discussed at a national workshop
sponsored by CDC in September 1998 and include a) improving estimates of the
burden of toxoplasmosis, b) improving diagnostic tests to determine when a person
becomes infected with
Toxoplasma
, and c) determining the applicability of national
screening programs.
Conclusion: Many cases of congenital toxoplasmosis can be prevented. Specific
measures can be taken by women and their health-care providers to decrease the risk
for infection during pregnancy and prevent severe illness in newborn infants.
60 MMWR March 31, 2000
INTRODUCTION
Toxoplasmosis is caused by infection with the protozoan parasite
Toxoplasma gondii
.
In the United States, an estimated 23% of adolescents and adults have laboratory evi-
dence of infection with
T. gondii
(
1
; CDC, unpublished data, 1994). Although these infec-
tions are usually either asymptomatic or associated with self-limited symptoms (e.g.,
fever, malaise, and lymphadenopathy), infection in immunosuppressed persons (e.g.,
persons with acquired immunodeficiency syndrome [AIDS]) can be severe. In addition,
infections in pregnant women can cause serious health problems in the fetus if the
parasites are transmitted (i.e., congenital toxoplasmosis) and cause severe sequelae in
the infant (e.g., mental retardation, blindness, and epilepsy). Although congenital toxo-
plasmosis is not a nationally reportable disease and no national data are available re-
garding its occurrence, extrapolation from regional studies indicates that an estimated
400–4,000 cases occur in the United States each year. In addition, of the 750 deaths
attributed to toxoplasmosis each year, 375 (50%) are believed to be foodborne, making
toxoplasmosis the third leading cause of foodborne deaths in this country (
2
).
In 1997, the U.S. Department of Health and Human Services, the U.S. Department of
Agriculture (USDA), and the U.S. Environmental Protection Agency (EPA) collaborated
to develop the National Food Safety Initiative (
3
). The project aims to reduce the inci-
dence of foodborne illness by enhancing surveillance, improving risk assessment, de-
veloping new research methods, and furthering food-safety education. Because con-
genital toxoplasmosis poses a substantial public health problem, CDC has developed
prevention recommendations to reduce the risk for congenital infections.
In September 1998, CDC convened the National Workshop on Toxoplasmosis: Pre-
venting Congenital Toxoplasmosis (NWTPCT) in Atlanta, Georgia, to discuss research
priorities for preventing the disease. Approximately 30 international and national ex-
perts in toxoplasmosis participated, representing universities, practitioner associations,
research institutions, health-care centers, and other federal agencies. Specific objectives
of NWTPCT included defining approaches for reducing the prevalence of congenital toxo-
plasmosis, determining the data needed to evaluate and implement these strategies,
and identifying critical research and prevention efforts for the future. This report summa-
rizes the recommendations from this workshop and the activities that have been under-
taken by CDC in response to these recommendations.*
SCOPE OF THE PROBLEM
Burden of Toxoplasmosis in the United States
Toxoplasmosis is not a nationally reportable disease in the United States, and no
reliable data are available at the national level about the number of cases diagnosed
each year. The most reliable information about the burden of toxoplasmosis in the
general population is derived from serosurveys, which determine the percentage of
persons with elevated levels of
Toxoplasma
-specific IgG antibodies.
*A separate effort at CDC deals with the prevention of opportunistic infections. Toxoplasmosis
can be a serious opportunistic infection in persons with AIDS, and specific recommendations
regarding how to prevent it have been published (
4
). Therefore, toxoplasmosis in persons
with AIDS is not the primary focus of this report.
Vol. 49 / No. RR-2 MMWR 61
Since the 1960s, rates of infection with
Toxoplasma
in the United States appear to be
declining. In the 1960s, a study of U.S. military recruits indicated that the overall
seroprevalence of
Toxoplasma
was 14% (
5
). In 1989, a second study of military recruits
indicated a seroprevalence of 9.6% (
6
). Similar downward trends have been observed in
France and Sweden (
7,8
).
The most reliable estimate of
Toxoplasma
seroprevalence in the United States is
derived from the third National Health and Nutrition Examination Survey (NHANES III)
(
1
), which was conducted during 1988–1994. The survey design was a cluster sample of
U.S. residents. Serum samples from 17,658 persons were tested at CDC for
Toxoplasma
-
specific IgG antibodies; 23% were positive. Of 5,988 women of childbearing age (i.e., age
12–49 years), 14% were seropositive (CDC, unpublished data, 1994). No recent U.S.
studies of a large population of pregnant women have been conducted to determine the
incidence of new infections during pregnancy.
Although serosurveys of the general population help define temporal trends in
Toxo-
plasma
seropositivity rates and can be used to estimate the number of women of child-
bearing age who are at risk for acquiring
Toxoplasma
infections and potentially trans-
mitting it to their fetuses, serosurveys are less helpful in estimating the number of
cases of congenital toxoplasmosis. Three prospective studies provide useful informa-
tion regarding the number of congenital toxoplasmosis cases in the United States.
Two prospective studies in the 1970s both reported rates of congenital toxoplasmosis
of approximately 10 per 10,000 live births. In one study in the early 1970s, 7,500 con-
secutive live births at a hospital in Birmingham, Alabama, were screened for
Toxoplasma
infection; of these, 10 (13 per 10,000 live births) were seropositive (
9
). In a study of acute
Toxoplasma
infection in 4,048 pregnant women in New York during 1967–1969, six (0.2%)
women seroconverted during their pregnancies, and 17 others (0.4%) had at least an
eightfold rise in antibody titers during pregnancy (
10
). Of the 23 infants born to these 23
women, three had congenital toxoplasmosis, representing an infection rate of 7 per
10,000 live births in the study population.
More recent data regarding the rate of congenital toxoplasmosis are available from
the New England Regional Newborn Screening Program (
11
). All infants born in the
catchment area of this program are tested for evidence of congenital toxoplasmosis;
infected infants undergo clinical evaluation and treatment for 1 year. During 1986–1992,
of 635,000 infants who underwent serologic testing, 52 were infected, representing an
infection rate of approximately 1 per 10,000 live births. Only two (4%) of these infants
were recognized to have congenital toxoplasmosis before the screening results were
known; however, follow-up examinations of 19 (40%) of the 48 infants evaluated re-
vealed signs of disease (e.g., abnormal cerebrospinal fluid examinations, hydroceph-
alus, and retinal lesions).
Whether the rates of congenital infection in these three studies are representative of
the entire U.S. population is unknown. However, if these rates (i.e., 1 per 10,000 and 10
per 10,000 ) were extrapolated to the approximately 4 million live births in the United
States each year, an estimated 400–4,000 infants would be born each year with congeni-
tal toxoplasmosis.
Limited data are available to assist in estimating the portion of the disease burden of
toxoplasmosis attributable to meat consumption. A recent study compared results from
a cross-sectional seroprevalence study of Seventh Day Adventists, a religious group
that follows a diet containing no meat, with serologic results from a control group of
62 MMWR March 31, 2000
volunteers who were not Seventh Day Adventists (
12
). Results from this study docu-
mented a significantly lower rate of
Toxoplasma
infection in Seventh Day Adventists
than the control group (24% versus 50%, respectively; p < 0.01). Thus, approximately
one half of
Toxoplasma
exposure might be caused by eating contaminated meat. Fur-
thermore, a statistically significant decrease in risk for infection was observed among
nonmeat eaters even after the data were adjusted for age and sex (odds ratio = 0.2; 95%
confidence interval = 0.1–0.5). Because this study was originally designed to evaluate the
possible association between eating shellfish and
Vibrio
and Norwalk virus infections,
important questions regarding toxoplasmosis (i.e., amount of meat consumed, contact
with or ownership of cats, or history of outdoor activity) were not asked in the interview.
A report conducted by USDA’s Economic Research Service concluded that one half of
the toxoplasmosis cases in the United States are caused by eating contaminated meat.
The estimated economic burden of these infections is $7.7 billion each year, primarily
from congenital toxoplasmosis (
13
).
Pork has been implicated by some authorities as the meat most commonly associ-
ated with foodborne toxoplasmosis (
14
). In some areas, market pigs from small pro-
ducers have had higher rates of
Toxoplasma
infections than pigs from larger producers
(
15
); however, overall rates appear to be declining over time (
16
). In 1992, a large
survey in Illinois documented that 3.1% of market pigs had serologic evidence of
Toxo-
plasma
infection (
16
).
Toxoplasma
infection has also been identified in other meats,
but their contribution to the burden of disease is believed to be small (
14
).
Although
Toxoplasma
infections are associated either with eating contaminated meat
or with ingesting oocysts passed in the feces of cats, no laboratory test exists that can
determine the origin of a
Toxoplasma
infection in a specific person and whether it was
associated with foodborne, catborne, or soilborne transmission. Epidemiologic studies of
the transmission of toxoplasmosis have been hindered by an inability to determine the
origin of isolated infections.
Diagnosis and Treatment
Acute toxoplasmosis is rarely diagnosed by detecting the parasite in body fluids,
tissue, or secretions; the most common method of diagnosis is based on antibody
detection. The presence of elevated levels of
Toxoplasma
-specific IgG antibodies indi-
cates infection has occurred at some point but does not distinguish between an infec-
tion acquired recently and one acquired in the distant past. The presence of a high
Toxoplasma
-specific IgM antibody titer combined with a high IgG titer probably indi-
cates an acute infection within the previous 3 months. A low-to-medium IgM titer and a
high IgG titer might indicate an acute infection 3–6 months previously, but IgM antibodies
have been detected as long as 18 months after initial infection (
17
). Determining when
Toxoplasma
infection occurred in a pregnant woman is particularly important because
infection before conception poses no substantial risk for transmission of infection to the
fetus; however, infection after conception does pose such risk.
In the United States, commercial test kits for
Toxoplasma
-specific IgG and IgM anti-
bodies are readily available. Some commercial IgM tests have had problems with speci-
ficity, resulting in unacceptably high rates of false-positive test results. In 1996, FDA and
CDC conducted extensive evaluations of the six most commonly used commercial IgM
kits in the United States to determine the extent of the problem with the specificity of
Vol. 49 / No. RR-2 MMWR 63
these kits. Sensitivity and specificity rates for these six kits ranged from 93.3% to 100.0%
and from 77.5% to 99.1%, respectively (
18
).
As a result of these findings, in 1997 FDA distributed an advisory to physicians in the
United States highlighting these test limitations. The agency provided a guide for inter-
preting test results and issued a recommendation to laboratory personnel and physi-
cians advising them to be aware of the problems associated with the test kits before
making decisions about the clinical management of their patients. In addition,
IgM-positive results should be confirmed by a
Toxoplasma
reference laboratory (
18
).
Treatment of toxoplasmosis in immunocompetent persons other than pregnant
women is generally not indicated unless symptoms are severe or persistent (
19–21
). In
immunocompromised persons, treatment usually consists of pyrimethamine and sul-
fadiazine. Depending on gestational age and whether the fetus is known to be infected,
pregnant women have been treated with the antibiotic spiramycin or with sulfadiazine
alone or the combination of pyrimethamine and sulfadiazine. Treatment of acute infec-
tion during pregnancy has been associated with an approximately 50% reduction in
fetal infection (
22
).
ETIOLOGIC FACTORS
T. gondii
has a complex life cycle consisting of three stages: a) tachyzoite — during
the acute stage of infection, this form of the parasite invades and replicates within
cells; b) bradyzoite — during latent infections, this form of the parasite is present in
tissue cysts; and c) sporozoite — this form of the parasite is found in oocysts, which are
environmentally resistant. Members of the family Felidae (including domestic and fe-
ral cats) are the definitive hosts of
Toxoplasma
. During acute infections, cats excrete
unsporulated (i.e., uninfectious) oocysts in their feces; after several days to several
weeks, depending on environmental conditions, the oocysts sporulate and become
infectious. Under favorable conditions (i.e., in warm, moist soil), oocysts can remain
infectious for approximately 1 year. They do not survive in arid, cool climates and can be
destroyed by heating (
17,19,20,23,24
).
Toxoplasmosis can be transmitted to humans by three principal routes. First, humans
can eat raw or inadequately cooked infected meat or eat uncooked foods that have come
in contact with contaminated meat. Second, humans can inadvertently ingest oocysts
that cats have passed in their feces, either in a cat litter box or outdoors in soil (e.g., soil
from gardening or unwashed fruits or vegetables). Third, a woman can transmit the
infection to her unborn fetus.
Women infected with
Toxoplasma
before conception, with rare exceptions, do not
transmit the infection to their fetuses. Women infected with
Toxoplasma
after concep-
tion (i.e., during pregnancy) can transmit the infection across the placenta to their fe-
tuses. Maternal infections early in pregnancy are less likely to be transmitted to the fetus
than infections later in pregnancy, but early fetal infections, when they do occur, are
more likely than later infections to be severe (
25
). An estimated one half of untreated
maternal infections are transmitted to the fetus.
The classic triad of signs suggestive of congenital toxoplasmosis include chorioretinitis,
intracranial calcifications, and hydrocephalus. However, most infants infected in utero
are born with no obvious signs of toxoplasmosis on routine examination, but many
64 MMWR March 31, 2000
develop learning and visual disabilities later in life (
26,27
). If untreated, congenital toxo-
plasmosis can be associated with severe and even fatal disease (
28
).
The severity of
Toxoplasma
infections is correlated with the immune status of the
infected person. Toxoplasmosis in immunocompetent adolescents or adults is gener-
ally mild or unapparent. Mild infections can result in lymphadenopathy, fever, fatigue,
and malaise, all of which usually resolve within weeks to months without specific treat-
ment. However, infection in immunocompromised persons can be severe. Immuno-
suppression caused by AIDS or therapies for malignancies, transplants, or
lymphoproliferative disorders can result in reactivation of preexisting latent
Toxoplasma
infections. Reactivation most often involves the central nervous system, and symp-
toms can include meningoencephalitis or symptoms of a mass lesion.
RECOMMENDATIONS FOR PREVENTION
• To prevent toxoplasmosis and other foodborne illnesses, food should be cooked
to safe temperatures. A food thermometer should be used to measure the
internal temperature of cooked meat to ensure that meat is cooked all the way
through. Beef, lamb, and veal roasts and steaks should be cooked to at least 145 F,
and pork, ground meat, and wild game should be cooked to 160 F before eating.
Whole poultry should be cooked to 180 F in the thigh to ensure doneness.
• Fruits and vegetables should be peeled or thoroughly washed before eating.
• Cutting boards, dishes, counters, utensils, and hands should always be washed
with hot soapy water after they have contacted raw meat, poultry, seafood, or
unwashed fruits or vegetables.
• Pregnant women should wear gloves when gardening and during any contact
with soil or sand because cat waste might be in soil or sand. After gardening or
contact with soil or sand, wash hands thoroughly.
• Pregnant women should avoid changing cat litter if possible. If no one else is
available to change the cat litter, use gloves, then wash hands thoroughly. Change
the litter box daily because
Toxoplasma
oocysts require several days to become
infectious. Pregnant women should be encouraged to keep their cats inside and
not adopt or handle stray cats. Cats should be fed only canned or dried
commercial food or well-cooked table food, not raw or undercooked meats.
• Health education for women of childbearing age should include information about
meat-related and soilborne toxoplasmosis prevention. Health-care providers
should educate pregnant women at their first prenatal visit about food hygiene
and prevention of exposure to cat feces.
• Health-care providers who care for pregnant women should be educated about
two potential problems associated with
Toxoplasma
serology tests. First, no
assay exists that can determine precisely when initial
Toxoplasma
infection
occurred. Second, in populations with a low incidence of
Toxoplasma
infection,
such as in the United States, a substantial proportion of the positive IgM test
results will probably be false positive.
Vol. 49 / No. RR-2 MMWR 65
• The government and the meat industry should continue efforts to reduce
Toxoplasma
in meat.
RESEARCH AGENDA
NWTPCT Recommendations for Research
Experts who participated in NWTPCT considered several issues regarding preven-
tion of this disease. These issues included the need to improve estimates of the burden of
toxoplasmosis and immunodiagnostics for the disease and to determine the applicability
of national toxoplasmosis screening for newborns. Participants discussed current knowl-
edge about these issues, gaps in current knowledge, and needs for future research.
Improving Estimates of the Burden of Toxoplasmosis
In their recommendations, NWTPCT participants emphasized the importance of ob-
taining more complete and accurate data regarding the incidence of new infections and
the number of cases by mode of transmission. Participants recommended that CDC
obtain population-based data regarding the incidence of and risk factors for toxoplasmo-
sis. In addition, participants recommended the use of existing private data systems (e.g.,
those of health-maintenance organizations and managed-care systems) for surveillance
and research, and development of techniques that would enable tracing the source of
individual infections to foodborne, catborne, or soilborne transmission.
Improving Immunodiagnostics for Toxoplasma
NWTPCT participants recommended that additional efforts were needed to develop
more accurate screening diagnostic tests and improved confirmatory tests. NWTPCT
participants also emphasized that resources should be identified to increase current
capacity to provide reference diagnostic services in the United States.
Determining the Applicability of National
Toxoplasmosis Screening for Newborns
Research is under way to determine the need for national toxoplasmosis screening
of newborn infants in the United States (See Exhibit). NWTPCT participants identified the
need for cost-effectiveness studies to enable comparison of the benefits of expanded
testing in the United States and the costs of such testing.
CDC Priorities
The Food Safety Initiative has enabled CDC to increase support for activities related
to prevention of toxoplasmosis, with a special emphasis on preventing congenital toxo-
plasmosis. The NWTPCT has helped CDC to identify high-priority activities and to form
important partnerships with other groups with similar goals.
CDC is engaged in several activities to improve the ability to measure the burden of
toxoplasmosis in the United States and to provide a baseline against which the impact of
future prevention efforts can be measured. Epidemiologic staff are analyzing
Toxoplasma
IgG seroprevalence in samples collected in the nationally representative NHANES III (
1
)
and preparing a document to disseminate the results. Plans are under way to conduct
66 MMWR March 31, 2000
serologic testing of samples obtained as part of NHANES 2000 to evaluate trends in the
prevalence of
Toxoplasma
infection and to assess the occurrence of acute
Toxoplasma
infections. In addition, CDC staff will examine national hospital discharge data and na-
tional death certificate data to monitor the annual number of cases of and deaths caused
by toxoplasmosis, the proportion of toxoplasmosis associated with congenital infection,
and the proportion associated with HIV infection. Other possible activities include a)
examination of surveillance data (obtained from both educational and medical records)
for multiple developmental disabilities (e.g., mental retardation, cerebral palsy, and hear-
ing and vision impairment) and evidence of positive
Toxoplasma
tests and b) the designa-
tion by state health departments of congenital toxoplasmosis as a reportable infection.
CDC is supporting a cost-effectiveness analysis of the New England Newborn Screen-
ing Program to provide background information for states considering newborn toxo-
plasmosis screening and reporting. One state has already received funding from CDC
through the Emerging Infections Program and has begun toxoplasmosis-related activi-
ties. Minnesota is conducting active surveillance for toxoplasmosis using laboratories,
ophthalmologists, infection-control practitioners, and other clinicians.
CDC is conducting research on the genetic variation of
Toxoplasma
to develop tools
that would enable molecular epidemiologic studies (e.g., to determine whether different
strains have different characteristics and are more infectious or pathogenic for humans).
The results of this research might help investigators describe the source and spread of
Toxoplasma
in outbreaks and differentiate between foodborne and cat feces or soilborne
Toxoplasma
infections. In addition, through FoodNet, CDC is querying laboratories in
eight states about their diagnostic practices for toxoplasmosis.
To help evaluate the accuracy of future commercial
Toxoplasma
antibody test kits,
CDC created a
Toxoplasma
serum panel that contains known positive and negative
sera. FDA now requires that any new commercial
Toxoplasma
test kit perform ad-
equately based on results obtained using this panel. The panel is available for purchase
through the CDC Technology Transfer Office.
The American College of Obstetricians and Gynecologists, with assistance from CDC,
is conducting a national survey of obstetricians to assess their knowledge about con-
genital toxoplasmosis and interpretation of related laboratory tests. The results of the
survey will be used to identify ways to educate health-care providers about diagnosis
and clinical management of pregnant women with suspected
Toxoplasma
infections.
To help educate women about toxoplasmosis prevention, CDC has published a pam-
phlet entitled “Attention Pregnant Women: What You Can Do to Keep Germs from Harm-
ing You and Your Baby,” which discusses, among other infections, toxoplasmosis and
ways to minimize the risk for infection during pregnancy. The pamphlet is available by
mail (CDC, National Center for Infectious Diseases, Division of Bacterial and Mycotic
Diseases, Respiratory Diseases Branch, MS C-23, 1600 Clifton Rd. N.E., Atlanta, GA
30333), fax ([404] 639-3970), or on the Internet at <http:// www.cdc.gov/ncidod/diseases>.
CONCLUSION
Many cases of congenital toxoplasmosis in the United States can be prevented. Spe-
cific measures can be taken by women and their health-care providers to decrease the
risk for infection during pregnancy and, if primary prevention fails and congenital infec-
tion occurs, to reduce the severity of infection in newborns. CDC is involved in efforts to
Vol. 49 / No. RR-2 MMWR 67
improve measurement of the burden of toxoplasmosis in the United States, evaluate
current prevention programs, train health-care providers, and educate women about
toxoplasmosis. These efforts should allow CDC and state and local health departments
to better monitor and reduce the impact of toxoplasmosis on pregnant women and their
newborn infants.
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Vol. 49 / No. RR-2 MMWR 69
70 MMWR March 31, 2000
Exhibit
Innovative and ambitious programs to prevent toxoplasmosis have been developed
in the United States and in Europe, and the National Workshop on Toxoplasmosis: Pre-
venting Congenital Toxoplasmosis (NWTPCT) provided a forum to compare current ef-
forts. These programs involve three approaches: a) screening pregnant women (or all
women of childbearing age) to detect as early as possible
Toxoplasma
infections (or
susceptibility to such infections) that might indicate a risk for congenital infection, b)
screening newborns to detect infections in infants as early as possible to enable early
initiation of treatment, and c) educating women about preventing infection.
Screening Programs for Pregnant Women
France
In France, a screening program was implemented in 1976 to detect and treat
Toxo-
plasma
infection during pregnancy. The goal of this program is to institute preventive
measures for seronegative women and to ensure early diagnosis and treatment of
infection acquired during pregnancy. Since the beginning of the program, premarital
and prenatal medical examinations for
Toxoplasma
antibodies have been performed.
Premarital examinations are conducted to distinguish previously infected women from
women who have not been previously infected. When a previously uninfected woman
becomes pregnant, testing is conducted at her first prenatal examination during her
first trimester and at six additional examinations conducted monthly during her second
and third trimesters. In addition, women are educated about prevention methods dur-
ing pregnancy (
29
). If these screening tests detect evidence of acute infection during
pregnancy, treatment for the woman is initiated with spiramycin. If infection in the
fetus is confirmed through fetal blood sampling and amniocentesis, pyrimethamine
and sulfadiazine or sulfadoxine is added to the regimen (
30–32
).
Even though coverage of the French program has been incomplete, the program has
been associated with a decline in the incidence of congenital infection, as well as a decline
in severe disease detected at birth. The proportion of the decline specifically attributable
to the program or to the general decline in Europe in rates of seropositivity is difficult to
determine because no unscreened group of women exists for comparison.
Austria
Austria implemented a toxoplasmosis screening program in 1975. Nearly all women
who become pregnant are serologically screened early in pregnancy and, if found to be
negative initially, are tested again during the second and third trimesters. Women with
Toxoplasma
infections are treated as soon as infection is detected. Although seroposi-
tivity rates among pregnant Austrian women have declined from approximately 50.0%
during the late 1970s to 36.7% during the early 1990s, the incidence of congenital
Toxo-
plasma
infection has declined even more, from 50–70 cases per 10,000 births before the
program to 1 per 10,000 births during the early 1990s (
33
). As with the French program,
the lack of an unscreened comparison group precludes determining the proportion of
Vol. 49 / No. RR-2 MMWR 71
the decline attributable to the screening program, and lack of cost figures precludes cost-
effectiveness analyses.
European Research Network on Congenital Toxoplasmosis
The European Research Network on Congenital Toxoplasmosis was established in
1993 and has sponsored several studies regarding public health interventions for con-
genital toxoplasmosis. Most recently, a multicenter study was conducted to evaluate
the effectiveness of toxoplasmosis treatment administered during pregnancy in pre-
venting transmission of maternal infection to the fetus. Pregnant women who visited
one of five European university medical centers for prenatal care were screened for
Toxoplasma
antibodies at their first prenatal visit. Women who were seronegative were
retested at least once every trimester in two centers and monthly in the other centers,
until the birth of the infant. For women who seroconverted during pregnancy, prenatal
antibiotic treatment was started, and their infants were followed for 1 year after birth.
Treatment regimens consisted of spiramycin or a combination of pyrimethamine and
sulfadiazine. If prenatal infection was confirmed with amniocentesis or cordocentesis,
women were treated with pyrimethamine and sulfadiazine or sulfadoxine. Of women
who screened positive and did not receive prenatal therapy, transmission from mother
to infant occurred in 72% of the mother-infant pairs; of women who received prenatal
therapy, transmission occurred in 39% of the mother-infant pairs. In addition, 20% of the
untreated mothers gave birth to infants with severe sequelae, and 3.5% of the treated
mothers gave birth to infants with severe sequelae. Furthermore, the earlier antibiotics
were administered after infection, the less likely sequelae were detected in the in-
fant (
34
).
Finland
From January 1988 through June 1989, a cost-benefit analysis of
Toxoplasma
screen-
ing during pregnancy was conducted in a prospective study in Finland. The study com-
pared costs of screening alternatives for primary infections during pregnancy with the
costs of no screening. With screening, the annual costs of congenital toxoplasmosis
were $95 US per pregnancy; without screening, annual costs were $128 US per preg-
nancy. Furthermore, screening along with health education was more beneficial than
health education alone (
35
). The study findings suggest screening is beneficial in coun-
tries with low incidence of congenital toxoplasmosis, such as Finland. The findings of
other studies suggest screening programs can also be beneficial in areas with high
incidences of congenital toxoplasmosis (
30,36,37
).
NWTPCT’s Assessment
Although the findings of the European studies suggest
Toxoplasma
screening pro-
grams of women of childbearing age can prevent cases of congenital toxoplasmosis,
several concerns could limit support for such programs in the United States. NWTPCT
participants identified the need for cost-effectiveness studies to enable comparison of
the benefits of expanded testing in the United States, the costs of such testing, and the
unintended adverse consequences that might accompany such testing (e.g., inappro-
priately treating women with false-positive test results).
72 MMWR March 31, 2000
Screening Programs for Newborns
Denmark
During June 1992–August 1996, researchers in Denmark conducted a newborn
screening study for toxoplasmosis. The primary goal of this study was to determine the
feasibility of screening newborn infants for congenital toxoplasmosis in an area with
low prevalence; in Denmark, the seroprevalence of antibodies to
Toxoplasma
among
women during this study was 28% (
38,39
). Approximately 90,000 infants were screened
for
Toxoplasma
-specific IgG antibodies 5–10 days after birth. Infants born to mothers
who seroconverted during pregnancy were subsequently examined physically and se-
rologically for 1 year; for those with confirmed congenital infections, treatment was
initiated with courses of pyrimethamine and sulfadiazine, alternating with spiramycin
(
38
). During 1996, serum levels of
Toxoplasma
-specific IgM antibodies were also deter-
mined. The IgM test conducted within 10 days of birth resulted in a false-positive rate of
0.2 per 1,000 with no false-negatives. Results from this study indicated that a newborn
screening program using a
Toxoplasma
-specific IgM antibody test exclusively could iden-
tify approximately 75% of infections in infants born to untreated mothers. In addition, the
low rates of false-positives and false-negatives suggested this method would be feasible
in large-scale newborn screening programs in areas with low seroprevalence rates of
toxoplasmosis.
United States
In the United States, the New England Newborn Screening Program tests newborn
“filter-paper” specimens from all infants born in Massachusetts and New Hampshire
for congenital toxoplasmosis by using a
Toxoplasma
-specific IgM antibody assay. If
IgM antibodies are detected, an extensive clinical evaluation is performed, and a 1-year
treatment regimen is initiated with a combination therapy of pyrimethamine and sulfa-
diazine (
11
). During 1986–1992, a total of 52 of the 635,000 infants screened had con-
firmed congenital infections; 50 appeared normal on routine neonatal examination and
had toxoplasmosis diagnosed through screening alone. After more intensive examina-
tion, 19 (40%) of the 48 evaluated infants who appeared normal on routine examination
had evidence of retinal or central nervous system disease. Treatment was provided for
these infants, and compliance with therapy was observed. After 1 year of treatment,
only one (2.2%) of 46 children had a neurologic deficit, and four (10.3%) of 39 had eye
lesions that could have developed after birth. The findings of this program demonstrated
that screening newborns for congenital toxoplasmosis is feasible in the United States.
The laboratory and personnel costs of screening approximately 100,000 infants per year
for
Toxoplasma
infection and following those who were infected totaled $220,000 or
approximately $30,000 per infant identified. Costs were relatively low because the sys-
tem used by the program to collect and process specimens was the same one already
used for screening newborns for eight other diseases. On the basis of these preliminary
cost estimates, this screening program appears to be a favorable alternative, consider-
ing the financial and social costs associated with raising a visually or mentally impaired
child (
40
).
Vol. 49 / No. RR-2 MMWR 73
NWTPCT’s Assessment
NWTPCT participants recognized the benefits of these newborn screening programs
and discussed ways to evaluate the New England program to determine the benefit of
using it as a model for developing additional programs in other areas of the United
States. One specific recommendation was for CDC to support a detailed, cost-
effectiveness evaluation of the program.
Education Programs for Women
The third approach to preventing toxoplasmosis focuses on educating women of
childbearing age about minimizing their risk for infection with
Toxoplasma
. Education
interventions assume that increased knowledge results in awareness, which conse-
quently results in changes in risky behavior and declines in infection rates. Messages
emphasize the importance of avoiding eating raw or undercooked meat, handling raw
meat safely, and washing hands after gardening or changing cat litter boxes (
37
).
Canada
A study conducted as part of prenatal classes at Canadian public health agencies
evaluated the effect of a 10-minute teaching session on three behaviors: practices as-
sociated with cleaning the cat litter box and limiting the cat’s diet to cooked food; safe
food-handling practices; and handwashing after exposure to cat feces, garden soil, or
raw meats. Among women in the classes, behavior improved regarding practices as-
sociated with cats; however, behavior regarding food-handling practices remained
unchanged. In addition, improvement occurred in handwashing practices but only
among professional women (
41
).
Belgium
During 1979–1986, a Belgium study assessed the effectiveness of educational ses-
sions held in hospital settings. Baseline data were collected during 1979–1982, when no
education measures were in effect. During 1983–1986, education sessions were pro-
vided to pregnant women. Although the intervention was associated with a 34% de-
crease in seroconversion rates, the decrease was not statistically significant (
42
).
NWTPCT’s Assessment
NWTPCT participants considered education programs to be a potentially powerful
intervention because of their low cost and because pregnant women were highly moti-
vated to protect the health of their babies. However, participants emphasized that the
impact of educational programs was difficult to evaluate because of the limited num-
ber of comparative studies a) conducted with rigorous scientific methodology and b) of
sufficient size to enable calculation of the effectiveness of the intervention compared
with its cost.
74 MMWR March 31, 2000
Professor Horst Aspöck
Department of Medical Parasitology
Clinical Institute of Hygiene
Kinderspitalgasse 15
A-1095 Vienna, Austria
Sue Binder, M.D.
Division of Parasitic Diseases
National Center for Infectious Diseases
CDC, MS F-22
4770 Buford Highway
Atlanta, Georgia 30341
Kenneth Boyer, M.D.
Department of Pediatrics
Rush Presbyterian/St. Luke’s Medical Center
1653 W. Congress Parkway
Chicago, Illinois 60612
Steve Crutchfield, Ph.D
U.S. Department of Agriculture
Room N 3077
1800 M Street N.W.
Washington, D.C. 20036-5831
Alfred DeMaria, Jr., M.D.
State Laboratory Institute
305 South Street
Jamaica Plain, Massachusetts 02130
Vance Dietz, M.D.
Division of Parasitic Diseases
National Center for Infectious Diseases
CDC, MS F-22
4770 Buford Highway
Atlanta, Georgia 30341
J.P. Dubey, Ph.D.
Zoonotic Diseases Laboratory
U.S. Department of Agriculture
Barc-East Bldg. 1040
Beltsville, Maryland 20705
Roger Eaton, Ph.D.
NE Newborn Screening Program
University of Massachusetts Medical School
305 South Street
Jamaica Plain, Massachusetts 02130
Ruth Etzel, M.D.
U.S. Department of Agriculture
Room 3718 Franklin Court
1400 Independence Avenue, S.W.
Washington, D.C. 20250-3700
Jack Frenkel, M.D.
1252 Vallecita Drive
Sante Fe, NM 87501-8803
Ronald Gibbs, M.D.
Department of Ob/Gyn
University of Colorado Health Sciences Center
4200 E. Ninth Avenue, Campus Box B-198
Denver, Colorado 80262
Ruth Gilbert, M.D.
Department of Epidemiology and
Public Health
Institute of Child Health
30 Guilford Street
London WC1 N 1EH, United Kingdom
Carol Herman, M.S.
OSB, Center for Devices & Radiological Health
Food and Drug Administration, HFZ-510
1350 Piccard Drive
Rockville, Maryland 20850
Peter Hotez, M.D.
Yale University School of Medicine
507 LEPH; 60 College Street
New Haven, Connecticut 06520
Dennis Juranek, D.V.M.
Division of Parasitic Diseases
National Center for Infectious Diseases
CDC, MS F-22
4770 Buford Highway
Atlanta, Georgia 30341
Ruth Lynfield, M.D.
Acute Disease Epidemiology Section
Minnesota Department of Health
717 Delaware Street, S.E.
Minneapolis, Minnesota 55440-9441
James McAuley, M.D.
Westside Center for Disease Control
2160 W. Ogden Avenue
Chicago, Illinois 60612
Participants in the
National Workshop on Toxoplasmosis:
Preventing Congenital Toxoplasmosis
Vol. 49 / No. RR-2 MMWR 75
Rima McLeod, M.D.
The University of Chicago
939 E. 57th Street (VSC, MC 2114)
Chicago, Illinois 60637
Martin Meltzer, Ph.D.
Office of the Director
National Center for Infectious Diseases
CDC, MS C-12
1600 Clifton Road, N.E.
Atlanta, Georgia 30333
Marilyn Mets, M.D.
Children’s Memorial Hospital
Division of Ophthalmology
2300 Children’s Plaza/Box 70
Chicago, Illinois 60614
Thomas Navin, M.D.
Division of Parasitic Diseases
National Center for Infectious Diseases
CDC, MS F-22
4770 Buford Highway
Atlanta, Georgia 30341
Eskild Petersen, M.D.
Laboratory of Parasitology
Statens Serum Institute
Artillerivej 5
DK-2300 Copenhagen S Denmark
Jack Remington, M.D.
Research Institute
Palo Alto Medical Foundation
860 Bryant Street
Palo Alto, California 94301
Rigoberto Roca, M.D.
Center for Drug Evaluation & Research
Food and Drug Administration, HFD-590
5600 Fishers Lane
Rockville, Maryland 20857
Peter Schantz, V.M.D.
Division of Parasitic Diseases
National Center for Infectious Diseases
CDC, MS F-22
4770 Buford Highway
Atlanta, Georgia 30341
Jack Schlater, D.V.M.
National Veterinary Services Laboratories
1800 Dayton Avenue
Ames, Iowa 50010
L. David Sibley, Ph.D.
Washington University School of Medicine
660 S. Euclid Avenue, Campus Box 8230
St. Louis, Missouri 63110-1093
Kirk Smith, D.V.M.
Acute Disease Epidemiology
MN Department of Health
717 Delaware Street, N.E.
Minneapolis, Minnesota 55414
Philippe Thulliez, M.D.
Laboratoire de la Toxoplasmose
Institut de Puériculture
26 Boulevard Brune
F-75014 Paris
France
Ralph Timperi, M.P.H.
State Laboratory Institute
Massachusetts Department of Health
305 South Street
Jamaica Plain, Massachusetts 02130-3597
Marianna Wilson, M.S.
Division of Parasitic Diseases
National Center for Infectious Diseases
CDC, MS F-13
4770 Buford Highway
Atlanta, Georgia 30341
76 MMWR March 31, 2000
March 31, 2000 / Vol. 49 / No. RR-2
Recommendations
and
Reports
Continuing Education Activity
Sponsored by CDC
CDC Recommendations Regarding Selected Conditions Affecting Women’s Health
EXPIRATION — MARCH 31, 2001
You must complete and return the response form electronically or by mail by March 31, 2001, to receive
continuing education credit. If you answer all of the questions, you will receive an award letter for 2.5 hours
Continuing Medical Education (CME) credit, 0.2 hour Continuing Education Units (CEUs), or 2.9 hours
Continuing Nursing Education (CNE) credit. If you return the form electronically, you will receive educational
credit immediately. If you mail the form, you will receive educational credit in approximately 30 days. No fees are
charged for participating in this continuing education activity.
INSTRUCTIONS
By Internet
1. Read this
MMWR
(Vol. 49, RR-2), which contains the correct answers to the questions beginning on the next
page.
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MMWR
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3. Select which exam you want to take and select whether you want to register for CME, CEU, or CNE credit.
4. Fill out and submit the registration form.
5. Select exam questions. To receive continuing education credit, you must answer all of the questions.
Questions with more than one correct answer will instruct you to “Indicate all that apply.”
6. Submit your answers no later than March 31, 2001.
7. Immediately print your Certificate of Completion for your records.
By Mail
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MMWR
(Vol. 49, RR-2), which contains the correct answers to the questions beginning on the next
page.
2. Complete all registration information on the response form, including your name, mailing address, phone
number, and e-mail address, if available.
3. Indicate whether you are registering for CME, CEU, or CNE credit.
4. Select your answers to the questions, and mark the corresponding letters on the response form. To receive
continuing education credit, you must answer all of the questions. Questions with more than one correct
answer will instruct you to “Indicate all that apply.”
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programs by the International Association for Continuing Education and Training and awards 0.2 hour Continuing Education
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of continuing education in nursing by the American Nurses Credentialing Center’s Commission on Accreditation.
CE-2 MMWR March 31, 2000
GOALS AND OBJECTIVES
This
MMWR
provides recommendations and other information to help health professionals improve skills in
protecting the health of women. The articles in this
MMWR
were developed by CDC staff. This
MMWR
is
intended to provide information to guide public health policy development, program management, and clinical
care related to women’s health. Upon completion of this educational activity, the reader should be able to
develop strategies to reduce the risk for hip fractures, develop strategies to reduce the risk for exercise-related
trauma, identify disease risk factors and prevention interventions for breast and cervical cancer, and develop
strategies to reduce the risk for toxoplasmosis during pregnancy.
To receive continuing education credit, please answer all of the following questions.
1. Factors strongly associated with the risk for hip fracture among older adults include . . .
A. sex.
B. race.
C. age.
D. current level of physical activity.
E. all of the above.
2. Research has demonstrated that the most effective component of a fall-prevention program
is . . .
A. education about personal fall risk factors.
B. exercise to improve strength and balance.
C. checklists to help identify and correct home hazards.
D. teaching persons how to safely walk up and down stairs.
E. encouraging the use of sturdy shoes when walking outside.
3. What is the most important risk factor for exercise-related injury among women?
A. Smoking.
B. Age.
C. Intensity, frequency, and duration of training.
D. Previous injury.
4. Men and women of the same physical fitness level, participating in the same activities, can
be expected to have similar incidences of injury.
A. True.
B. False.
5. The greatest reduction in breast cancer mortality, following detection by mammography
screening at regularly scheduled intervals, has been reported among . . .
A. women aged 30–39 years.
B. women aged 40–49 years.
C. women aged >50 years.
D. women aged 50–69 years.
E. none of the above.
Vol. 49 / No. RR-2 MMWR CE-3
6. What is the main purpose for receiving Pap tests at regularly scheduled intervals?
A. To detect and treat vaginal and vulvar cancer.
B. To detect and treat invasive cervical cancer.
C. To identify and treat precancerous cervical lesions.
D. B and C.
E. None of the above.
7. Which of the following should be recommended to pregnant women to prevent exposure
to
T. gondii
?
A. Do not eat raw or undercooked meat; wash hands and surfaces with warm soapy water
after they have contacted raw meat, poultry, seafood, or unwashed fruits or vegetables.
B. If no one else is available to change cat litter, use gloves, then wash hands thoroughly
after changing cat litter and change it daily.
C. Peel or thoroughly wash fruits and vegetables before eating.
D. Do not pet cats.
E. A, B, and C.
8. Which of the following have contributed to the difficulties in diagnosing acute
toxoplasmosis in pregnant women?
A. Symptoms of the disease are mild or unapparent.
B. High false-positive rate of commercial IgM laboratory tests for diagnosing
toxoplasmosis.
C. Patient’s lack of knowledge regarding exposure to
T. gondii
.
D. All of the above.
9. Indicate your work setting.
A. State/local health department.
B. Other public health setting.
C. Hospital clinic/private practice.
D. Managed-care organization.
E. Academic institution.
F. Other.
10. Which best describes your professional activities?
A. Infectious diseases.
B. Obstetrics/gynecology.
C. Internal medicine.
D. Pediatrics.
E. Family practice.
F. Other.
CE-4 MMWR March 31, 2000
11. Each month, approximately how many women aged ³65 years do you treat for fall-related
injuries?
A. None.
B. 1–5.
C. 6–20.
D. 21–50.
E. 51–100
F. >100
12. Each month, approximately how many women do you treat for exercise-related injuries?
A. None.
B. 1–5.
C. 6–20.
D. 21–50.
E. 51–100
F. >100
13. Each month, approximately how many women do you treat for breast or cervical cancer?
A. None.
B. 1–5.
C. 6–20.
D. 21–50.
E. 51–100
F. >100
14. Each month, approximately how many women do you treat for toxoplasmosis?
A. None.
B. 1–5.
C. 6–20.
D. 21–50.
E. 51–100
F. >100
Vol. 49 / No. RR-2 MMWR CE-5
15. How much time did you spend reading this report and completing the exam?
A. 1 to 1½ hours.
B. More than 1½ hours but fewer than 2 hours.
C. 2 to 2 ½ hours.
D. More than 2 ½ hours but fewer than 3 hours.
E. 3 hours or more.
16. After reading this report, I am confident I can develop strategies to reduce the risk for hip
fracture.
A. Strongly agree.
B. Agree.
C. Neither agree nor disagree.
D. Disagree.
E. Strongly disagree.
17. After reading this report, I am confident I can develop strategies to reduce the risk for
exercise-related trauma.
A. Strongly agree.
B. Agree.
C. Neither agree nor disagree.
D. Disagree.
E. Strongly disagree.
18. After reading this report, I am confident I can identify disease risk factors and prevention
interventions for breast and cervical cancer.
A. Strongly agree.
B. Agree.
C. Neither agree nor disagree.
D. Disagree.
E. Strongly disagree.
19. After reading this report, I am confident I can develop strategies to reduce the risk for
toxoplasmosis during pregnancy.
A. Strongly agree.
B. Agree.
C. Neither agree nor disagree.
D. Disagree.
E. Strongly disagree.
CE-6 MMWR March 31, 2000
20. Overall, the presentation of the report enhanced my ability to understand the material.
A. Strongly agree.
B. Agree.
C. Neither agree nor disagree.
D. Disagree.
E. Strongly disagree.
21. These recommendations will affect my practice.
A. Strongly agree.
B. Agree.
C. Neither agree nor disagree.
D. Disagree.
E. Strongly disagree.
[Correct answers for questions 1–8]
[1. E; 2. B; 3. C; 4. A; 5. D; 6. D; 7. E; 8. D.]
Vol. 49 / No. RR-2 MMWR CE-7
MMWR
Response Form for Continuing Education Credit
March 31, 2000/Vol. 49/No. RR-2
CDC Recommendations Regarding Selected Conditions Affecting Women’s Health
To receive continuing education credit, you must
1. provide your contact information;
2. indicate your choice of CME, CNE, or CEU credit;
3. answer all of the test questions;
4. sign and date this form or a photocopy;
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Failure to complete these items can result in a delay or rejection of
your application for continuing education credit.
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Fill in the appropriate blocks to indicate your answers. Remember, you must answer
all of the questions to
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1. [ ] A [ ] B [ ] C [ ] D [ ] E 16. [ ] A [ ] B [ ] C [ ] D [ ] E
2. [ ] A [ ] B [ ] C [ ] D [ ] E 17. [ ] A [ ] B [ ] C [ ] D [ ] E
3. [ ] A [ ] B [ ] C [ ] D 18. [ ] A [ ] B [ ] C [ ] D [ ] E
4. [ ] A [ ] B 19. [ ] A [ ] B [ ] C [ ] D [ ] E
5. [ ] A [ ] B [ ] C [ ] D [ ] E 20. [ ] A [ ] B [ ] C [ ] D [ ] E
6. [ ] A [ ] B [ ] C [ ] D [ ] E 21. [ ] A [ ] B [ ] C [ ] D [ ] E
7. [ ] A [ ] B [ ] C [ ] D [ ] E
8. [ ] A [ ] B [ ] C [ ] D
9. [ ] A [ ] B [ ] C [ ] D [ ] E [ ] F
10. [ ] A [ ] B [ ] C [ ] D [ ] E [ ] F
11. [ ] A [ ] B [ ] C [ ] D [ ] E [ ] F
12. [ ] A [ ] B [ ] C [ ] D [ ] E [ ] F
13. [ ] A [ ] B [ ] C [ ] D [ ] E [ ] F
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15. [ ] A [ ] B [ ] C [ ] D [ ] E
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