Lifetime and baseline alcohol intake and risk of cancer of the upper aero-digestive tract in the European prospective investigation into cancer and nutrition (EPIC) study
Recent alcohol consumption is an established risk factor for squamous cell carcinoma (SCC) of the upper aero-digestive tract. In contrast, the role of lifetime exposure to alcohol with regard to risk of SCC is not well established. Historical data on alcohol use are available in 271,253 participants of the European Prospective Investigation into Cancer and Nutrition (EPIC). During 2,330,381 person years, 392 incident SCC cases (279 men and 113 women) were identified. Cox regression was applied to model sex-specific associations between lifetime alcohol intake and SCC risk adjusting for potential confounders including smoking. Compared to men who drank 0.1-6.0 g/day alcohol at lifetime, the relative risks (RR) for developing SCC were significantly increased for men who drank 30.1-60.0 g/day (RR 1.65, 95% confidence interval: 1.00-2.71), 60.1-96.0 g/day (RR 2.20, 95%CI 1.23-3.95), and >96.0 g/day, (RR 4.63, 95% CI 2.52-8.48), and for former drinkers (RR 4.14, 95%CI 2.38-7.19). These risk estimates did not considerably change when baseline alcohol intake was analyzed. Compared to women who drank 0.1-6.0 g/day alcohol intake at lifetime, the RR were significantly increased for women who drank >30 g/d (RR 6.05, 95%CI 2.98-12.3). Applying similar categories, the relative risk for baseline alcohol intake was 3.26 (95%CI 1.82-5.87). We observed a stronger association between alcohol intake at lifetime and risk of SCC in women compared to men (p for interaction 5 0.045). The strong dose-response relation for lifetime alcohol use underscores that alcohol is an important risk factor of SCC of the upper aero-digestive tract throughout life.