WASHINGTON – Long-term dual-antiplatelet therapy may provide a mortality benefit over aspirin alone in patients with symptomatic peripheral artery disease.
In an observational study of 629 patients with claudication or critical limb ischemia, the 348 who were on dual antiplatelet therapy (DAPT) with aspirin plus clopidogrel had a 3-year all-cause mortality rate of 11%, compared with 21% for those on aspirin monotherapy, Dr. Ehrin J. Armstrong said at the annual meeting of the American College of Cardiology.
The group on DAPT also had a significantly lower 3-year rate of major adverse cardiovascular events: 20%, compared with 28% in the monotherapy group. However, this was driven by the reduced risk of mortality. Rates of nonfatal MI and stroke were similar in the two groups. So were rates of lower extremity bypass surgery and major amputations, according to Dr. Armstrong, a cardiologist at the University of California, Davis.
The group on DAPT had a significantly higher baseline prevalence of diabetes at the time of angiography: 54%, compared with 45% for patients on aspirin alone. The DAPT group also had a higher baseline prevalence of known coronary artery disease – 56% vs. 45% – and greater use of beta-blockers, by a margin of 55%, compared with 48%. In a multivariate regression analysis adjusted for these and other potential confounders, DAPT was associated with a 45% reduction in the risk of mortality and a 35% decrease in major adverse cardiovascular events.
The rate of the combined endpoint of death or major amputation was 18% in the DAPT group and 27% with aspirin monotherapy, for a highly significant 47% relative risk reduction.
Although a study such as this can’t be considered definitive, these data suggest DAPT is worth considering in patients with symptomatic peripheral artery disease, the cardiologist said.
He reported having no financial conflicts of interest.