NMA: Nonprescription Medicines Academy

Low-Dose Aspirin Associated With 55% Increased Relative Risk of Major Bleeding-But Not in Diabetes

August 1st, 2012

In a population-based cohort study that used administrative data from 4.1 million citizens in 12 local health authorities in Puglia, Italy, daily use of low-dose aspirin was significantly associated with an increased risk of major gastrointestinal or cerebral bleeding episodes, and the incidence of major bleeding events was five times higher than that reported by the Antithrombotic Trialists’ Collaboration. However, aspirin therapy only marginally increased the risk of bleeding in patients with diabetes.

The analysis included 186,425 individuals being treated with low-dose aspirin and 186,425 matched controls without aspirin use. During a median follow-up of 5.7 years, a total of 6,907 first episodes of major bleeding requiring hospitalization were registered, including 4,487 episodes of gastrointestinal bleeding and 2,464 episodes of intracranial hemorrhage. The overall incidence rate of hemorrhagic events was 5.58 (95% CI, 5.39–5.77) per 1,000 person-years for aspirin users and 3.60 (95% CI, 3.48–3.72) per 1,000 person-years for those without aspirin use; the associated incidence rate ratio (IRR) was 1.55 (95% CI, 1.48–1.63). The use of aspirin was not associated with a greater risk of major bleeding in patients with diabetes (IRR, 1.09; 95% CI, 0.97–1.22). However, diabetes was independently associated with an increased risk of major bleeding episodes irrespective of aspirin use (IRR, 1.36; 95% CI, 1.28–1.44).

The authors concluded that diabetes might represent a different population in terms of both expected benefits and risks associated with antiplatelet therapy.

JAMA. 2012;307:2286-94.