Does alcohol increase breast cancer risk in African-American women? Findings from a case-control study.

Background: Alcohol is an important risk factor for breast cancer in Caucasian women, but the evidence in African-American (AA) women is limited and results are inconclusive.

Methods: Associations between recent and lifetime drinking and breast cancer risk were evaluated in a large sample of AA women from a case-control study in New York and New Jersey. Multivariable logistic regression models provided odds ratios (ORs) and 95% confidence intervals (CIs).

Results: There was no association between recent drinking and breast cancer risk, even when stratified by menopausal status or by hormone receptor status. A borderline decreased risk with increased lifetime consumption was found (OR=0.77; 95% CI: 0.58-1.03), which was stronger among women who drank when under 20 years of age (OR=0.65; 95% CI: 0.47-0.89), regardless of menopausal or hormone receptor status.

Conclusion: Breast cancer risk associated with recent alcohol consumption was not apparent in AA women, while early age drinking seemed to decrease risk. This is the first investigation on recent and lifetime drinking in subgroups and drinking during different age periods in AA women. If findings are replicated, racial differences in biological pathways involving alcohol and its metabolites should be explored.