In adults with diabetes mellitus (DM), aspirin use prevented serious vascular events but also caused major bleeding events, a recent study found. Researchers randomly assigned adults who had diabetes but no evident cardiovascular (CV) disease to receive aspirin (100 mg daily) or matching placebo. The primary efficacy outcome was the first serious vascular event and the primary safety outcome was the first major bleeding events. Secondary outcomes included gastrointestinal tract cancer. Among the findings:

• 15,480 participants underwent randomization.
• During a mean follow-up of 7.4 years, serious vascular events occurred in a significantly lower percentage of those in the aspirin group vs the placebo group (658 vs 743; rate ratio, 0.88).
• Major bleeding events occurred in 314 (4.1%) participants in the aspirin group vs 245 (3.2%) in the placebo group (rate ratio, 1.29); most of the excess being gastrointestinal bleeding and other extracranial bleeding.
• There was no significant difference between groups in the incidence of gastrointestinal tract cancer.