Diabetes primary prevention of cardiovascular events

Overview
Diabetics are 2-4 times more likely to sustain a cardiovascular event when compared to age and sex matched controls Given the high risk of diabetic patients for cardiovascular events, there is tremendous ongoing interest in identifying therapies that might prevent a first event. In 2004, the U.S. Preventive Services Task Force recommended low dose aspirin as a primary preventive strategy in men aged 45 to 79 years and in women age 55 to 79 years, irrespective of the presence of diabetes. The safety and efficacy of low-dose aspirin in the primary prevention of cardiovascular events in patients with type 2 diabetes remains controversial.

Primary Prevention with Aspirin
In one prospective, randomized, multicenter, blinded trial, 2,539 type 2 diabetes patients with no history of atherosclerotic events were followed for a median of 4.4 years were randomized to either low-dose aspirin (81 or 100 mg per day) or placebo control. There was no difference in the risk of fatal or nonfatal ischemic heart disease, fatal or nonfatal stroke, and peripheral arterial disease: 13.6 events per 1000 person-years in the aspirin group vs 17.0 per 1000 person-years in the non-aspirin group, hazard ratio [HR], 0.80; 95% confidence interval [CI], 0.58-1.10; log-rank test, P = .16). For the secondary endpoint of fatal coronary events and fatal cerebrovascular events, there was a significant advantage of low dose aspirin:  there was 1 stroke among the patients treated with aspirin and there were 5 fatal myocardial infarctions and 5 fatal strokes in the nonaspirin group (HR, 0.10; 95% CI, 0.01-0.79; P = .0037). With respect to all cause mortality, 34 aspirin patients and 38 non-aspirin patients died from any cause (HR, 0.90; 95% CI, 0.57-1.14; log-rank test, P = .67).  Thus, although the results were somewhat mixed, the primary endpoint did not favor aspirin, among patients with type 2 diabetes, and the use of low-dose aspirin was not judged to be effective in primary prevention of atherosclerotic events.