Alcohol intake and risk of renal cell carcinoma: a meta-analysis of published case-control studies

Introduction: While some studies have indicated that alcohol intake is associated with a decreased risk of renal cell carcinoma, others have not. We conducted a meta-analysis of case-control studies to provide a quantitative assessment of the association between alcohol intake and the risk of renal cell carcinoma. Material and methods: We identified studies by a literature search of PubMed and review of references of relevant articles. Both the fixed and random-effects models were used to obtain the summary risk estimates associated with the highest versus the lowest consumption categories depending on the heterogeneity of effects among studies. Dose-response meta-analysis was performed for studies reporting categorical risk estimates for a series of exposure levels. Results: Fifteen studies were included in this meta-analysis. An inverse association between alcohol consumption and renal cell carcinoma was observed in both the overall alcohol intake group (OR 0.67, 95% CI 0.62-0.73) and subgroups stratified by sex, study design, geographical region, specific beverages and alcohol assessment. The dose-response meta-analysis showed that an increase in alcohol consumption of 12 g of ethanol per day was associated with a 5% statistically significant decreased risk of renal cell cancer. Conclusions: High alcohol consumption exhibits a preventive effect for renal cell carcinoma in a dose-response manner. Further efforts should be made to clarify the underlying biological mechanisms.