Recreational physical activity and the risk of breast cancer in postmenopausal women: the Women's Health Initiative Cohort Study
Authors
McTiernan, AnneKooperberg, Charles L.
White, Emily
Wilcox, Sara
Coates, Ralph
Adams-Campbell, Lucile L.
Woods, Nancy F.
Ockene, Judith K.
UMass Chan Affiliations
Department of Medicine, Division of Preventive and Behavioral MedicineDocument Type
Journal ArticlePublication Date
2003-09-10Keywords
AgedBreast Neoplasms
*Exercise
Female
Humans
Incidence
Middle Aged
Postmenopause
Prospective Studies
Recreation
Risk
Life Sciences
Medicine and Health Sciences
Women's Studies
Metadata
Show full item recordAbstract
CONTEXT: Women who are physically active have a decreased risk for breast cancer, but the types, amounts, and timing of activity needed are unknown. OBJECTIVE: To prospectively examine the association between current and past recreational physical activity and incidence of breast cancer in postmenopausal women. DESIGN, SETTING, PATIENTS: Prospective cohort study in 74 171 women aged 50 to 79 years who were recruited by 40 US clinical centers from 1993 through 1998. MAIN OUTCOME MEASURE: Incident invasive and in situ breast cancer. RESULTS: We documented 1780 newly diagnosed cases of breast cancer over a mean follow-up of 4.7 years. Compared with less active women, women who engaged in regular strenuous physical activity at age 35 years had a 14% decreased risk of breast cancer (relative risk [RR], 0.86; 95% confidence interval [CI], 0.78-0.95). Similar but attenuated findings were observed for strenuous physical activity at ages 18 years and 50 years. An increasing total current physical activity score was associated with a reduced risk for breast cancer (P =.03 for trend). Women who engaged in the equivalent of 1.25 to 2.5 hours per week of brisk walking had an 18% decreased risk of breast cancer (RR, 0.82; 95% CI, 0.68-0.97) compared with inactive women. Slightly greater reduction in risk was observed for women who engaged in the equivalent of 10 hours or more per week of brisk walking. The effect of exercise was most pronounced in women in the lowest tertile of body mass index (BMI) (CONCLUSIONS: These data suggest that increased physical activity is associated with reduced risk for breast cancer in postmenopausal women, longer duration provides most benefit, and that such activity need not be strenuous.Source
JAMA. 2003 Sep 10;290(10):1331-6. Link to article on publisher's siteDOI
10.1001/jama.290.10.1331Permanent Link to this Item
http://hdl.handle.net/20.500.14038/50882PubMed ID
12966124Related Resources
Link to article in PubMedae974a485f413a2113503eed53cd6c53
10.1001/jama.290.10.1331