Aspirin and Alcohol in Relation to Lethal Prostate Cancer

Abstract

Problem: Prostate cancer is the most commonly diagnosed cancer and second-leading cancer cause of death among U.S. men. However, most prostate cancers are indolent. Thus, it is necessary to identify risk factors for lethal (metastatic or fatal) prostate cancer. This dissertation investigates the role of aspirin use and alcohol intake in relation to prostate cancer. Methods: Data from two large, longitudinal studies of U.S. adult males – the Physicians’ Health Study (PHS) and Health Professionals Follow-up Study (HPFS) – were used. PHS began in 1981 as a randomized trial of aspirin and beta carotene among 22,071 U.S. male physicians. HPFS began in 1986 when investigators enrolled 51,529 U.S. male health professionals. In both cohorts, regular questionnaires ascertained medical diagnoses, medications, diet, and lifestyle factors. Cox proportional hazards regression was used to investigate all associations. Results: In the general study population, compared to never use, current aspirin use was associated with decreased risk of lethal prostate cancer (Hazard Ratio [HR], 95% Confidence Intervals [CI]: PHS: = 0.80, 0.66-0.96; HPFS: 0.80, 0.66-0.96). Findings were similar when assessing post-diagnosis aspirin use among patients. Total pre-diagnosis alcohol intake was associated with a decreased risk of lethal prostate cancer in HPFS (0.84, 0.71-0.99). Among patients, compared to none, any red wine after diagnosis was associated with a decreased risk of lethal prostate cancer (0.50, 0.29-0.86) and overall mortality (0.74, 0.57-0.97). Conclusions: Recommending aspirin use to men with and without prostate cancer may help prevent lethal prostate cancer. Moderate alcohol intake did not increase risk of lethal prostate cancer, suggesting it may be part of a healthy diet among older men. Red wine may be beneficial. In all analyses, we were unable to differentiate a late effect from reverse causation.