Statin use and mortality risk in Asian patients with prostate cancer receiving androgen deprivation therapy: A population-based cohort study

Background: This study aimed to examine the associations between the use of statins concurrent with androgen deprivation therapy (ADT) and the risks of mortality in Asian patients diagnosed with prostate cancer (PCa).Methods: Adult patients (>= 18 years old) diagnosed with PCa who were receiving any form of ADT and were being treated at public hospitals in Hong Kong from December 1999 to March 2021 were retrospectively identified, with follow-up conducted until September 2021. Patients who had received medical castration for <180 days without subsequent bilateral orchidectomy, those who had used statins concurrently with ADT for <180 days, and those with missing baseline total cholesterol levels were excluded. Statin users were defined as individuals who had used statins for >= 180 days concurrent with ADT, while non-users were those who had not used any statins. PCa-related mortality was the primary outcome, while all-cause mortality served as the secondary outcome. Inverse probability treatment weighting was employed to balance the covariates.Results: A total of 4920 patients were included, consisting of 2578 statin users and 2342 non-users (mean age 76.1 +/- 8.2 years). Over a mean follow-up period of 4.2 +/- 3.3 years, it was observed that statin users had significantly lower risks of both PCa-related mortality (weighted hazard ratio [wHR] 0.56 [95% confidence interval (CI) 0.48, 0.65], p < 0.001) and all-cause mortality (wHR 0.57 [95% CI 0.51, 0.63], p < 0.001), regardless of the type of ADT used. Notably, these associations were more pronounced among patients with less advanced PCa, as indicated by the absence of androgen receptor antagonist or chemotherapy usage (p value for interaction <0.001 for both outcomes).Conclusion(s): The use of statins concurrent with ADT was associated with reduced mortality risks among Asian patients with PCa. These findings suggest the need for additional research to explore the potential role of statins in the treatment of PCa patients.