Hirko, Kelly A.Lucas, Darek R.Pathak, Dorothy R.Hamilton, Ann S.Post, Lydia M.Ihenacho, UgonnaCarnegie, Nicole BohmeHouang, Richard T.Schwartz, KendraVelie, Ellen M.2023-10-312023-10-312023-10Hirko, K.A., Lucas, D.R., Pathak, D.R. et al. Lifetime alcohol consumption patterns and young-onset breast cancer by subtype among Non-Hispanic Black and White women in the Young Women’s Health History Study. Cancer Causes Control (2023). https://doi.org/10.1007/s10552-023-01801-z1573-7225https://scholarworks.montana.edu/handle/1/18178copyright Springer Nature 2023Purpose. The role of alcohol in young-onset breast cancer (YOBC) is unclear. We examined associations between lifetime alcohol consumption and YOBC in the Young Women’s Health History Study, a population-based case–control study of breast cancer among Non-Hispanic Black and White women < 50 years of age. Methods. Breast cancer cases (n = 1,812) were diagnosed in the Metropolitan Detroit and Los Angeles County SEER registry areas, 2010–2015. Controls (n = 1,381) were identified through area-based sampling and were frequency-matched to cases by age, site, and race. Alcohol consumption and covariates were collected from in-person interviews. Weighted multivariable logistic regression was conducted to calculate adjusted odds ratios (aOR) and 95% confidence intervals (CI) for associations between alcohol consumption and YOBC overall and by subtype (Luminal A, Luminal B, HER2, or triple negative). Results. Lifetime alcohol consumption was not associated with YOBC overall or with subtypes (all ptrend ≥ 0.13). Similarly, alcohol consumption in adolescence, young and middle adulthood was not associated with YOBC (all ptrend ≥ 0.09). An inverse association with triple-negative YOBC, however, was observed for younger age at alcohol use initiation (< 18 years vs. no consumption), aOR (95% CI) = 0.62 (0.42, 0.93). No evidence of statistical interaction by race or household poverty was observed. Conclusions. Our findings suggest alcohol consumption has a different association with YOBC than postmenopausal breast cancer—lifetime consumption was not linked to increased risk and younger age at alcohol use initiation was associated with a decreased risk of triple-negative YOBC. Future studies on alcohol consumption in YOBC subtypes are warranted.en-UScopyright Springer Nature 2023https://www.springer.com/gp/rights-permissions/obtaining-permissions/882lifetime alcohol consumptionalcholol consumption patternsyoung-onset breast cancerNon-Hispanic Black and White womenyoung women's heathArticle