A Randomized Trial of Low-Dose Aspirin in the Prevention of Clinical Type 2 Diabetes in Women

Abstract

Objective: Subclinical inflammation is linked with the development of type 2 diabetes and epidemiologic data suggest this association may be stronger in women. While small clinical studies have shown prominent hypoglycemic effect of short-term high-dose aspirin, no randomized trials have directly evaluated the efficacy of aspirin in diabetes prevention at doses acceptable for use in routine clinical practice. We evaluated whether chronic low-dose aspirin prevents the development of clinical diabetes among initially healthy American women.

Research Design and Methods: Subjects were enrolled in the Women's Health Study, a 10-year randomized double-blind, placebo-controlled trial of aspirin and vitamin E for primary prevention of cardiovascular disease and cancer. Between 1992 and 1995, 38,716 women aged ≥ 45 years and free of clinical diabetes were randomized to either low-dose aspirin or placebo (median follow-up 10.2 years). Documented clinical type 2 diabetes was prospectively evaluated throughout the trial.

Results: Among women randomly assigned to receive aspirin (n=19,326) or placebo (n=19,390), there was no statistically significant difference in the incidence of type 2 diabetes. There were 849 cases in the aspirin group and 847 in the placebo group (RR 1.01; CI 0.91-1.11). Stratification by diabetes risk factors including age, BMI, family history of diabetes, physical activity, hemoglobin A1c and high-sensitivity C-reactive protein did not support a modulating effect of these variables. Analyses accounting for treatment duration and adherence similarly found no beneficial effects.

Conclusion: These data suggest that long-term low-dose aspirin does not prevent the development of clinical type 2 diabetes in initially healthy women.