Low-Dose Aspirin for Primary Prevention of Cardiovascular Events in Patients With Diabetes: A Meta-Analysis

Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, 73104, USA.
The American Journal of the Medical Sciences (Impact Factor: 1.52). 01/2011; 341(1):1-9. DOI: 10.1097/MAJ.0b013e3181f1fba8
Source: PubMed

ABSTRACT The use of low-dose aspirin for primary prevention of cardiovascular events in patients with diabetes is recommended by existing guidelines, but definitive evidence supporting its efficacy is lacking. The authors undertook a meta-analysis of published trials to determine the effect of low-dose aspirin for primary prevention of cardiovascular events in patients with diabetes.
Randomized controlled trials comparing low-dose aspirin versus placebo or no treatment in patients with diabetes (either exclusively or as a subgroup) with no previous history of cardiovascular disease were identified through MEDLINE and EMBASE databases.
Seven randomized controlled trials met the inclusion criteria. Two studies included exclusively patients with diabetes, whereas the remaining 5 studies included patients with diabetes as a subgroup. Two studies were excluded because they did not provide diabetes-specific data. Overall, aspirin was associated with a nonsignificant reduction in the hazard rate of the composite endpoint of major cardiovascular events compared with control (hazard ratio = 0.89, 95% confidence interval: 0.70-1.13, P = 0.33). Similarly, there was a nonsignificant reduction in the hazard rate of the individual endpoints of myocardial infarction, stroke, cardiovascular and all-cause mortality. The risk of major bleeding increased nonsignificantly with aspirin compared with control (relative risk = 3.02, 95% confidence interval: 0.48-18.86, P = 0.24).
The role of low-dose aspirin for primary prevention of cardiovascular events in patients with diabetes remains unproven, and its routine use cannot be justified at present. More trials are needed to definitively address this issue.

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