A meta-analysis of allopurinol therapy and the risk of prostate cancer

OBJECTIVE: The aim of the study was to investigate the risk of prostate cancer among people with gout and/or hyperuricemia who used allopurinol and who did not use allopurinol. METHODS: We conducted a meta-analysis to identify the cohort and case-control studies by searching PubMed and Web of Science. We used the random-effects model to calculate the pooled risk ratio with 95% confidence interval for the risk of prostate cancer associated with allopurinol treatment. RESULTS: There were 5 cohort studies and 2 case-control studies included in the meta-analysis. All 7 eligible studies were published between 2012 and 2021. The study period ranged from 8 to 13years. The number of study subjects ranged from 25,770 to 1,623,550. The age of study subjects ranged from 20 to 99years. Overall, allopurinol treatment was not associated with the risk of prostate cancer (risk ratio = 1.13, 95% confidence interval = 0.96-1.34 and P = .13). The heterogeneity was high between studies (I(2) = 93%). CONCLUSIONS: Our meta-analysis reveals that no association can be found between allopurinol treatment and the risk of prostate cancer among people with gout and/or hyperuricemia. We propose that the inhibition of xanthine oxidase and the reduction of serum uric acid via allopurinol treatment do not affect the probability of developing prostate cancer. Further studies are needed to confirm our findings. KEY POINTS: No association can be found between allopurinol treatment and the risk of prostate cancer. The inhibition of xanthine oxidase and the reduction of serum uric acid via allopurinol treatment do not affect the probability of developing prostate cancer.