Alcohol intake and renal cell cancer in a pooled analysis of 12 prospective studies

Background: The association between alcohol intake and risk of renal cell cancer has been inconsistent in case-control studies. An inverse association between alcohol intake and risk of renal cell cancer has been suggested in a few prospective studies, but each of these studies included a small number of cases. Methods: We performed a pooled analysis of 12 prospective studies that included 530469 women and 229575 men with maximum follow-up times of 7-20 years. All participants had completed a validated food-frequency questionnaire at baseline. Using the primary data from each study, the study-specific relative risks (RRs) for renal cell cancer were calculated using Cox proportional hazards models and then pooled using a random-effects model. All statistical tests were two-sided. Results: A total of 1430 (711 women and 719 men) cases of incident renal cell cancer were identified. The study-standardized incidence rates of renal cell cancer were 23 per 100000 person-years among nondrinkers and 15 per 100000 person-years among those who drank 15 g/day or more of alcohol. Compared with nondrinking, alcohol consumption (≥15 g/day, equivalent to slightly more than one alcoholic drink per day) was associated with a decreased risk of renal cell cancer (pooled multivariable RR = 0.72, 95% confidence interval = 0.60 to 0.86; P_trend<.001); statistically significant inverse trends with increasing intake were seen in both women and men. No difference by sex was observed (P_{heterogeneity} = .89). Associations between alcohol intake and renal cell cancer were not statistically different across alcoholic beverage type (beer versus wine versus liquor) (P = .40). Conclusion: Moderate alcohol consumption was associated with a lower risk of renal cell cancer amon g both women and men in this pooled analysis. The Author 2007. Published by Oxford University Press.