American Journal of Epidemiology Advance Access originally published online on June 18, 2009
American Journal of Epidemiology 2009 170(3):308-317; doi:10.1093/aje/kwp120
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
ORIGINAL CONTRIBUTIONS |
Alcohol and Risk of Breast Cancer by Histologic Type and Hormone Receptor Status in Postmenopausal Women
The NIH-AARP Diet and Health Study
Correspondence to Dr. Yikyung Park, Nutritional Epidemiology Branch, Division of Cancer Epidemiology and Genetics, 6120 Executive Boulevard, Rockville, MD 20852 (e-mail: parkyik{at}mail.nih.gov).
Received for publication January 15, 2009. Accepted for publication April 24, 2009.
Little is known about the association between alcohol and breast cancer by different tumor characteristics. The study consisted of 184,418 postmenopausal women aged 50–71 years in the National Institutes of Health-AARP Diet and Health Study (1995–2003). Alcohol use, diet, and potential risk factors for cancer were assessed with a mailed questionnaire at baseline. The relative risks and 95% confidence intervals were estimated by using Cox proportional hazards regression. Breast cancer cases and estrogen receptor and progesterone receptor status were identified through linkage to state cancer registries. During an average of 7 years of follow-up, 5,461 breast cancer cases were identified. Alcohol was significantly positively associated with total breast cancer: Even a moderate amount of alcohol (>10 g/day) significantly increased breast cancer risk. In a comparison of >35 g versus 0 g/day, the multivariate relative risks were 1.35 (95% confidence interval (CI): 1.17, 1.56) for total breast cancer, 1.46 (95% CI: 1.22, 1.75) for ductal tumors, and 1.52 (95% CI: 0.95, 2.44) for lobular tumors. The multivariate relative risks for estrogen receptor-positive/progesterone receptor-positive, estrogen receptor-positive/progesterone receptor-negative, and estrogen receptor-negative/progesterone receptor-negative tumors were 1.46 (95% CI: 1.12, 1.91) for >35 g versus 0 g/day, 1.13 (95% CI: 0.73, 1.77) for >20 g versus 0 g/day, and 1.21 (95% CI: 0.79, 1.84) for >20 g versus 0 g/day, respectively. Moderate consumption of alcohol was associated with breast cancer, specifically hormone receptor-positive tumors.
alcohol drinking; breast neoplasms; carcinoma, ductal, breast; carcinoma, lobular; receptors, estrogen; receptors, progesterone
Abbreviations: CI, confidence interval; ER+, estrogen receptor positive; ER–, estrogen receptor negative; MHT, menopausal hormone therapy; NIH, National Institutes of Health; PR+, progesterone receptor positive; PR–, progesterone receptor negative