Comparison of efficacy of antiplatelet treatments for patients with claudication

Summary

It was the aim of the present study to investigate if antiplatelet treatment reduced cardiovascular events in patients with claudication and/ or an ankle/brachial index (ABI) ≤0.99 and to analyse if specific antiplatelet treatment had a different impact on clinical outcome. We performed a meta-analysis of 29 clinical randomized trials on antiplatelet therapy for prevention of vascular death, myocardial infarction, and stroke in 10,735 peripheral artery disease patients. The primary end-point utilizing in the meta-analysis construction was Cardiovascular Adverse Event. We found 1,900 (17.70%) patients in trials with aspirin, 5,326 (49.61%) in those with thienopyridines, 2,324 (21.65%) in those with picotamide and 1,185 (11.04 %) in those with others antiplatelet drugs. A statistically significant effect of antiplatelet treatment [odds ratio (OR) 0.839; 95% confidence interval (CI) 0.729–0.965; p=0.014] was observed. There was a statistically significant reduction of clinical outcome [OR 0.779; 95% CI 0.639–0.950; p=0.014] in the thienopyridine-treated group vs. control. Patients treated with picotamide [OR 0.785; 95% CI 0.495–1.243; p=0.302] or aspirin [OR 0.847; 95%CI 0.653–1.097; p=0.084] showed reduced cardiovascular outcomes, that, however, did not reach significance. The study confirms that anti-platelet treatment reduces vascular outcome in claudicants. Significant reduction was observed with thienopyridines while data regarding aspirin and picotamide were inconclusive.

Keywords

Antiplatelet agents - atherosclerosis - atherothrombosis - clinical trials - antiplatelet drugs - vasculopathies

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