Updated recommendations on daily aspirin use in patients with diabetes.

Persons with diabetes mellitus have two to four times the risk of cardiovascular events compared with persons of the same age and sex who do not have the disease. Coronary heart disease (CHD) is responsible for more than two-thirds of deaths in persons with diabetes who are older than 65 years. Although aspirin has been proven to reduce cardiovascular morbidity and mortality rates in high-risk patients with myocardial infarction or stroke, its benefit is unclear in patients without a history of cardiovascular events. In 2007, the American Diabetes Association and American Heart Association recommended aspirin therapy (75 to 162 mg daily) for primary prevention in patients with diabetes who had increased CHD risk (e.g., older than 40 years, smoking, family history of cardiovascular disease). Since these recommendations were published, new evidence has raised questions about the effectiveness of this strategy. The U.S. Preventive Services Task Force recently recommended that physicians encourage aspirin use in men 45 to 79 years of age and in women 55 to 79 years of age, regardless of whether they have diabetes. To address the uncertainties about aspirin use in persons with diabetes, experts from the American Diabetes Association, American Heart Association, and American College of Cardiology Foundation reviewed the current evidence and updated the 2007 recommendations. The group organized its recommendations around the following questions: • What is the evidence for aspirin in preventing initial cardiovascular events in patients with diabetes? • How can the conflicting results of various primary prevention trials be reconciled? • What are the risks of aspirin therapy, and are these risks similar for patients with diabetes compared with those for patients without the disease? • What is the recommended dosage? • How should the potential benefits and risks of aspirin therapy be integrated to determine which patients should take aspirin daily for the primary prevention of cardiovascular events? The current evidence on aspirin therapy for prevention of cardiovascular disease includes three trials conducted in patients with diabetes, and six trials containing subgroups of patients with diabetes. None of these trials provides definitive results, so the group performed a meta-analysis to reconcile the available data. Data from subgroups of patients with diabetes from the six trials were included in a previous metaanalysis by the Antithrombotic Trialists’ Collaboration. These were combined with data from the Japanese Primary Prevention of Atherosclerosis With Aspirin for Diabetes study, the Prevention of Progression of Arterial Disease and Diabetes trial, and the Early Treatment of Diabetic Retinopathy Study. A random-effects model showed that aspirin use is associated with nonsignificant decreases in the risk of CHD events (relative risk [RR] = 0.91; 95% confidence interval Updated Recommendations on Daily Aspirin Use in Patients with Diabetes