AHA/ADA vs. ESC/EASD recommendations on aspirin as a primary prevention strategy in people with diabetes: how the same data generate divergent conclusions.

Recently, major scientific societies in Europe and USA have issued guidelines on diabetes and cardiovascular (CV) disease. The conclusions of the two panels of experts regarding the use of aspirin for the primary prevention of CV disease in individuals with diabetes are totally divergent. The US statement recommends the use of aspirin for primary prevention in all individuals aged > 40 or with additional risk factors. In contrast, in the European guidelines there is no mention of aspirin for the primary prevention of myocardial infarction or CV death, while it is recommended for the prevention of stroke. Both recommendations seem mainly based on extrapolations from data on other high-risk groups, rather than on a comprehensive review of pertinent data. Actually, a body of evidence suggests that the efficacy of aspirin in patients with diabetes is substantially lower than in individuals without diabetes. Nevertheless, existing knowledge is mainly derived from dated trials, including small numbers of patients, and hardly representing current strategies for the management of CV risk factors. The high level of uncertainty regarding the balance between benefits and risks of aspirin therapy have important implications for clinical practice, auditing activities, and the design and conduct of randomized clinical trials.