IMPACT of putative chemopreventative agents on prostate cancer diagnosis.

Abstract

e16553 Background: Prostate cancer (PC) is the most common non-cutaneous cancer in men and the third most common cause of cancer death in males. Several studies have shown that use of commonly prescribed medications, is associated with improved survival in various malignancies, including PC. There has not been any large population-based study, examining the effects of these and other commonly prescribed medications, such as proton pump inhibitors (PPI), on the rate of PC diagnosis, PC advanced disease and PC-specific death. Methods: A retrospective population-based study using data from the institute of clinical evaluative sciences, including all male patients aged 65 and above in Ontario who have had a negative first prostate biopsy between 1994 and 2016. We assessed the impact of commonly prescribed medications on PC outcomes. The analyzed medications included Statins (hydrophilic and hydrophobic), most commonly used diabetes drugs (metformin, insulins, sulfonylureas, and thizolidinedions), PPIs, 5 alpha reductase inhibitors, and alpha blockers. Time dependent Cox regression proportional hazards models were performed to determine predictors of PC diagnosis, PC advanced disease (defined as usage of hormonal therapy), and PC-specific death. Medication exposure was time varying and modelled as “ever” vs. “never” use or as cumulative exposure. Results: A total of 21,562 men were analyzed over a mean (SD) follow-up time of 8.06 (5.44) years. Overall, 5,187 patients (24%) were diagnosed with PC, 7861 (36.5%) had died, and 647 (3%) died of PC. On multivariable analysis usage of hydrophilic statins modelled as “ever vs. never” was associated with a lower diagnosis rate (OR 0.832, 95% CI 0.732-0.946, p = 0.005) and a significantly decreased PC-specific death (OR 0.676, 95% CI 0.528-0.871, p = 0.0024). In contrast, Pantoprazole was associated with a higher rate of advanced PC disease when modelled as cumulative exposure of 6 months (OR 1.03, 95% CI 1.003-1.06, P = 0.031), and PC-specific death, when modeled as “ever vs. never” (OR 1.26, 95% CI 1.02-1.576, p = 0.031). Conclusions: Hydrophilic statins were associated with a clinically and statistically significant lower PC diagnosis and PC-specific death, while pantoprazole was associated with a higher rate of advanced PC disease and PC-specific death.