Association between lifetime alcohol consumption and prostate cancer risk: A case-control study in Montreal, Canada.
Résumé
Alcohol intake may increase the risk of prostate cancer (PCa). Many previous studies harbored important methodological limitations.
We conducted a population-based case-control study of PCa comprising 1933 cases and 1994 controls in Montreal, Canada. Lifetime alcohol consumption was elicited, by type of beverage, during in-person interviews. Odds ratios (OR) and 95% confidence intervals (CI) assessed the association between alcohol intake and PCa risk, adjusting for potential confounders and considering the subjects' PCa screening history.
We observed a weak, non-significant positive association between high consumption of total alcohol over the lifetime and risk of high-grade PCa (OR=1.18, 95% CI 0.81-1.73). Risk estimates were more pronounced among current drinkers (OR=1.40, 95%CI 1.00-1.97), particularly after adjusting for the timing of last PCa screening (OR=1.52, 95%CI 1.07-2.16). These associations were largely driven by beer consumption. The OR for high-grade PCa associated with high beer intake was 1.37 (95%CI 1.00-1.89); it was 1.49 (95%CI 0.99-2.23) among current drinkers and 1.68 (95% CI 1.10-2.57) after adjusting for screening recency. High cumulative consumption of spirits was associated with a lower risk of low-grade PCa (OR=0.75, 95%CI 0.60-0.94) but the risk estimate no longer achieved statistical significance when restricting to current users. No association was found for wine consumption.
Findings add to the accumulating evidence that high alcohol consumption increases the risk of high-grade PCa. This association largely reflected beer intake in our population, and was strengthened when taking into account PCa screening history.