Meta-analysis: Aspirin for cardiovascular primary prevention in patients with and without diabetes

According to a report published early online in Diabetes Care, the relative benefit of aspirin for primary prevention of cardiovascular events is similar in patients with and without diabetes.

This finding comes from a systematic review and meta-analysis, which set out to estimate the efficacy of aspirin for the primary prevention of cardiovascular events among patients with diabetes, and to estimate the extent to which the effect of aspirin differs in patients with and without diabetes.

Nine RCTs of aspirin for primary prevention of cardiovascular events with moderate to high methodological quality were identified. The ratios of relative risks of the benefit of aspirin among patients with diabetes compared to patients without diabetes for the following outcomes were reported:

• Mortality: 1.12 (95% CI, 0.92 to 1.35)
• Myocardial infarction: 1.19 (0.82 to 1.17)
• Ischaemic stroke: 0.70 (0.25 to 1.97)

The researchers conclude “while there are insufficient data among patients with diabetes to conclusively show a benefit of aspirin therapy for the primary prevention of cardiovascular events, our data suggest, but do not confirm, that the relative benefit of aspirin is similar in patients with and without diabetes. Additional evidence from RCTs and individual-patient-data meta-analyses may help to further clarify this issue.”

Diabetes Care, published early online 9 September 2009; doi: 10.2337/dc09-1297 (link to abstract)
11 September 2009