Objective
To evaluate the impact of post‐diagnostic metformin or statin use and duration on risk of biochemical recurrence in a racially‐diverse cohort of Veterans.
Methods
The population consisted of men diagnosed with prostate cancer in the Veterans Health Administration and treated with either radical prostatectomy or radiation (Full cohort n = 65,759, Black men n = 18,817, White men n = 46,631, Other = 311). The association between post‐diagnostic (1) metformin and (2) statin use with biochemical recurrence was assessed using multivariable, time‐varying Cox Proportional Hazard Models for the overall cohort and by race. In a secondary analysis, metformin and statin duration were evaluated.
Results
Post‐diagnostic metformin use was not associated with biochemical recurrence (multivariable‐adjusted hazard ratio [aHR]: 1.01; 95% confidence interval [CI]: 0.94, 1.09), with similar results observed for both Black and White men. However, duration of metformin use was associated with a reduced risk of biochemical recurrence in the cohort overall (HR: 0.94; 95% CI: 0.92, 0.95) as well as both Black and White men. By contrast, statin use was associated with a reduced risk of biochemical recurrence (HR: 0.83; 95% CI: 0.79, 0.88) in the overall cohort as well as both White and Black men. Duration of statin use was also inversely associated with biochemical recurrence in all groups.
Conclusion
Post‐diagnostic metformin and statin use have the potential to prevent biochemical recurrence in men diagnosed with prostate cancer.