Lifetime Alcohol Intake, Binge Drinking Behaviors, and Breast Cancer Risk

The prevalence of binge drinking in the United States is rising. While alcohol is a risk factor for breast cancer, less is known about the impact of episodic heavy drinking. In 2003-2009, women aged 35-74 years who were free of breast cancer were enrolled in the Sister Study (n = 50,884). Residents of the United States or Puerto Rico who had a sister with breast cancer were eligible. Multivariable Cox regression was used to estimate adjusted hazard ratios and 95% confidence intervals for breast cancer. During follow-up (mean = 6.4 years), 1,843 invasive breast cancers were diagnosed. Increased breast cancer risk was observed for higher lifetime alcohol intake (for ≥230 drinks/year vs.