Differences in mortality risk associated with statin use amongst Asian patients with prostate cancer undergoing androgen deprivation therapy: a retrospective cohort study

Abstract Background: With known anticancer properties, statins have the potential to be an adjuvant cancer therapy, but their associations with mortality in prostate cancer (PCa) remain debatable. This study investigated the associations between statin use concurrent with androgen deprivation therapy (ADT) and mortality risks in Asian patients with PCa. Methods: Adults with PCa receiving any ADT attending public hospitals in Hong Kong between December 1999 and March 2021 were retrospectively identified, with follow-up until September 2021. Patients with <180 days of medical castration without subsequent bilateral orchidectomy, <180 days of concurrent statin use and ADT, or missing total cholesterol level at baseline were excluded. Statin users had ≥180 days of concurrent statin and ADT use, while non-users were those without any statin use. The primary outcome was PCa-related mortality. The secondary outcome was all-cause mortality. Inverse probability treatment weighting was used to balance covariates. Results: 4920 patients were studied (2578 statin users and 2342 non-users; mean age 76.1±8.2 years). Over a mean follow-up of 4.2±3.3 years, statin users had significantly lower risks of PCa-related mortality (weighted hazard ratio (wHR) 0.56 [95% confidence interval 0.48, 0.65], p<0.001) and all-cause mortality (0.57 [0.51, 0.63], p<0.001) regardless of the type of ADT. The associations appeared stronger in patients without chemotherapy or antiandrogens use. Conclusions: Statin use concurrent with ADT was associated with lower risks of mortality in Asian patients with PCa, warranting further studies of its role in the treatment of patients with PCa.