Lifetime physical activity and risk of breast cancer.
We conducted a case-control study of 394 women with breast cancer and 788 control women (91% response) to investigate the association of lifetime physical activity with mainly menopausal breast cancer risk. After controlling for potential confounders, the odds ratios (95% confidence intervals) for increasing quartiles of lifetime physical activity were 1.00 (referent), 0.91 (0.60-1.37), 0.91 (0.60-1.39), and 1.10 (0.73-1.67), respectively; P, trend = 0.47. We also separately examined physical activity at ages 12-18, 19-34, 35-49 and > or =50 years; no significant trends were observed in any age group. These data do not support a role of physical activity in preventing breast cancer.
Lee
I M
IM
Division Preventive Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, 900 Commonwealth Avenue East, Boston, MA 02215, USA.
Cook
N R
NR
Rexrode
K M
KM
Buring
J E
JE
D000293:Adolescent; D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000209:etiology / Q000517:prevention & control*; D016022:Case-Control Studies; D002648:Child; D015444:Exercise; D005260:Female; D006801:Humans; D008593:Menopause; D008875:Middle Aged; D016017:Odds Ratio; D010809:Physical Fitness; D012307:Risk Factors