Statin use and survival in men receiving androgen-ablative therapies for advanced prostate cancer: A systematic review and meta-analysis of cohort studies.

Abstract

83 Background: Mounting evidence support a role for statins in improving survival in advanced prostate cancer (PC), particularly among men on androgen-ablative therapies. This study aimed to systemically review and meta-analyze the relationship between statin use and survival among men with PC on androgen deprivation therapy (ADT) or androgen receptor-axis-targeted therapies (ARATs). Methods: This review was conducted in accordance with the Cochrane Handbook for Systematic Reviews and reported in compliance with the MOOSE guidelines. Medline, Embase, Epub Ahead of Print, Cochrane CT, Cochrane SR, and Web of Science were searched from inception to May 18, 2021, for observational studies reporting associations of postdiagnostic statin use and survival outcomes (hazard ratios [HRs]). Two authors independently abstracted all data. Study quality was assessed using the Newcastle-Ottawa Scale. The primary outcomes included overall mortality (OM) and Prostate cancer-specific mortality (PCSM). Summary estimates pooled multivariable HRs with 95% confidence intervals (CIs) using the generic inverse variance method with random-effects modelling. Heterogeneity was assessed and quantified. A priori subgroup and sensitivity analyses were undertaken, and publication bias was evaluated. Confidence in the evidence was assessed using GRADE. Results: Twenty-five cohorts of 119,878 men (64,717 statin users [54%]) with over 74,416 mortality events were included. Postdiagnostic statin use was associated with a 27% reduction in the risk of OM (19 cohorts, HR 0.73 [95%CI: 0.66 to 0.82], I2= 83%) and a 35% reduction in the risk of PCSM (14 cohorts, HR 0.65 [95%CI: 0.58 to 0.73], I2= 74%), with significant heterogeneity in both estimates. Subgroup analyses identified a PCSM-advantage of statins for men on ARATs compared to ADT (HR 0.40 [95%CI: 0.30 to 0.55] vs HR 0.68 [95%CI: 0.60 to 0.76], p-difference < 0.01). Confidence in the overall evidence was “low” for both outcomes. Conclusions: Postdiagnostic statin use reduced both overall and prostate cancer-specific mortality in men on androgen-ablative therapies for advanced PC. Randomized controlled trials are warranted to validate these findings.