Myocardial infarction and gastro-intestinal bleeding risks associated with aspirin use among elderly individuals with type 2 diabetes

Introduction. The benefit of aspirin in primary prevention of myocardial infarction and the associated gastro-intestinal bleeding risks have not been well established in the elderly population with diabetes. Methods. Using Quebec administrative databases, we conducted two nested case-control analyses within a cohort of individuals aged >= 66 years newly treated with an oral antidiabetes drug between 1998 and 2003. The 28,067 individuals had no cardiovascular disease recorded in the database in the year prior cohort entry. They had not used prescribed aspirin, antiplatelet, or anticoagulant drugs, and were not hospitalized for gastro-intestinal bleeding in the year prior cohort entry. The odds of myocardial infarction and gastro-intestinal bleedings were compared between individuals who were current, past, or non-users of aspirin. Results. There were 1101 (3.9%) cases of myocardial infarction. Compared to non-users, neither aspirin users (OR 0.89; 95% CI 0.71-1.13) nor aspirin past users (0.81; 0.62-1.06) showed a statistically significant lower risk of myocardial infarction. There were 373 (1.3%) cases of gastro-intestinal bleeding. Current users of aspirin had about a 2-fold greater risk of gastro-intestinal bleeding compared to non-users (2.19; 1.53-3.13). Conclusions. Our results suggest that individual assessment of bleeding risk and cardiovascular risk is mandatory among elderly people with diabetes before introducing aspirin therapy.