Effect of long term aspirin use on the incidence of prostate cancer: A systematic review and meta-analysis

Background: Previous studies found divergent effects of aspirin use on prostate cancer incidence, potentially due to studies with short durations of aspirin use and insufficient adjustment for screening.

Methods: A systematic review on the association between aspirin use ≥3 years and incident prostate cancer was performed in accordance with the PRISMA and MOOSE criteria.

Results: In the cohort studies, aspirin use for at least 3 years was associated with a lower incidence rate of prostate cancer (Odds ratio (OR) 0.88, 95% CI 0.80-0.97). No protective association was established for the case-control studies (OR 0.92, 95% CI 0.68-1.23). Subgroup analysis of advanced and aggressive cancers showed a protective association (OR 0.82, 95% CI 0.71-0.94 and OR 0.75, 95% CI 0.61-0.97).

Conclusion: This synthesis of observational studies suggests a potential protective association between long term aspirin use and incident prostate cancer. The current literature is highly heterogenous and suffers from inconsistent aspirin dose definition and measurement.