The American Diabetes Association recommends low-dose aspirin (75-162mg per day) for adults with diabetes and no previous history of vascular disease, but with a 10-year risk of cardiovascular events greater than 10% and who do not have an increased risk for bleeding. However, as the benefits of low-dose aspirin in the primary prevention setting are modest, any benefit of low-dose aspirin could be offset by the risk of bleeding. This study aimed to determine the incidence of major gastrointestinal and intracranial bleeding episodes in individuals with and without diabetes who were taking aspirin.
Administrative data were used from 4.1 million citizens in Puglia, Italy. Individuals with new prescriptions for low-dose aspirin (≤300 mg) were identified during the index period from January 1, 2003, to December 31, 2008, and were propensity-matched on a 1-to-1 basis with individuals who did not take aspirin over this period. The main outcomes measure was hospitalisations for major GI bleeding or cerebral haemorrhage.
186,425 individuals taking low-dose aspirin were compared with 186,425 matched controls who were not using aspirin; median follow-up was 5.7 years. The overall incidence rate of hemorrhagic events was 5.58 (95% CI, 5.39-5.77) per 1000 person-years for aspirin users and 3.60 (95% CI, 3.48-3.72) per 1000 person-years for those not taking aspirin (incidence rate ratio [IRR], 1.55; 95% CI, 1.48- 1.63). Of note, the use of aspirin was associated with a greater risk of major bleeding in most of the subgroups investigated but not in individuals with diabetes (IRR, 1.09; 95% CI, 0.97-1.22). However, irrespective of aspirin use, diabetes was independently associated with an increased risk of major bleeding episodes (IRR, 1.36; 95% CI, 1.28-1.44).
Aspirin use for primary prevention of cardiovascular disease is associated with an increased risk of both cerebral and gastrointestinal haemorrhage, which in this study was higher than previously reported. Diabetics had 36% increased risk of major bleeding episodes irrespective of aspirin use.