Aspirin use and risk of type 2 diabetes in apparently healthy men

Epidemiologic data on aspirin use and the risk of diabetes are limited. The Physician's Health Study has accumulated 22 years of follow-up data, including 5 years of randomized data, from 22,071 apparently healthy men.

At baseline and in yearly follow-up questionnaires, participants self-reported a history of diabetes, aspirin use, and various lifestyle factors. To evaluate the association between aspirin use and risk of subsequent diabetes, we used a Cox proportional hazards model with time-varying regression coefficients. During the 22 follow-up years, 1719 cases of diabetes were reported. The multivariable-adjusted hazard ratio of developing diabetes was 0.86 (95% confidence interval [CI], 0.77-0.97) for those who self-selected any aspirin. During the 5 years of randomized treatment, 318 cases of diabetes were observed, with a hazard ratio of 0.91 (95% CI, 0.73-1.14) for those randomized to aspirin.

Our data suggest a small but not significant decrease in the risk of diabetes during 5 years of randomized comparison of 325 mg of aspirin every other day. This trend was continued during 22 years of follow-up, indicating that self-selection of any use of aspirin is associated with a significant, approximately 14% decrease in the risk of diabetes. Decreased risk of type 2 diabetes may be added to the list of the clinical benefits of aspirin.