Use of Aspirin to Reduce Risks of Cardiovascular Disease in Patients With Diabetes

In their third version of U.S. federal guidelines, the National Cholesterol Education Program Adult Treatment Panel III elevated diabetes from a major risk factor to a coronary heart disease (CHD) risk equivalent (1, 2). The rationale for this change derives, in part, from earlier observations that patients with diabetes have several-fold increased risks of CHD (3), which are even greater in women than men (4). In fact, it has been suggested that at any given age, diabetes eliminates the lower absolute risk of CHD in women compared with men. Specifically, a middle-aged woman with diabetes has an absolute risk of CHD approximately equal to her male counterpart without diabetes. Furthermore, in a prospective cohort study, nondiabetic subjects with prior CHD had a 7-year event rate of ∼18.8%, whereas diabetic subjects without prior CHD had an event rate of ∼20% (5). Whether such high absolute risks apply to patients with newly diagnosed diabetes is less clear. Nonetheless, current U.S. federal guidelines recommend that patients with diabetes be treated just as aggressively as secondary prevention patients without diabetes (i.e., those who have already experienced a CHD event). With respect to secondary prevention, aspirin conclusively reduces risks of subsequent myocardial infarction (MI) by about one-third, stroke by about one-fourth, and vascular death by about one-sixth (6, 7). In primary prevention, aspirin conclusively reduces the risk of a first MI by about one-third, but the numbers of strokes and vascular deaths in the five published primary prevention trials preclude firm conclusions. Nonetheless, based on meta-analyses of risks (8) and benefits (9), recent U.S. Preventive Services Task Force Guidelines recommend that aspirin also be considered for all apparently …