Dual Antiplatelet Therapy Continuation beyond 1 Year after Drug-Eluting Stents: A Meta-Analysis of Randomized Trials

Background - The benefits and harms of dual antiplatelet therapy (DAPT) continuation beyond 1 year after drug-eluting stent implantation as compared with 1-year DAPT remain controversial. Methods and Results - We searched for randomized trials that compared longer than 1-year DAPT versus 1-year DAPT after drug-eluting stenting. A meta-analysis was performed by using standard frequentist and random-effects Bayesian approaches. Four trials comprising 17 650 participants were included. Compared with 1-year DAPT, extended DAPT did not affect all-cause mortality (odds ratio [OR], 1.11; 95% confidence interval [CI], 0.79-1.5; P=0.53) or cardiovascular mortality (OR, 1.03; 95% CI, 0.72-1.46; P=0.88). Extended DAPT was associated with a reduction in the risk of myocardial infarction (OR, 0.56; 95% CI, 0.43-0.73; P<0.001), nonsignificant reductions of stent thrombosis (OR, 0.46; 95% CI, 0.16-1.27; P=0.13), similar risk of stroke (OR, 0.91; 95% CI, 0.65-1.26; P=0.56), and an increased risk of major bleeding (OR, 1.49; 95% CI, 1.06-2.11; P=0.02). By using Bayesian meta-analysis, we found moderate evidence of a reduction of myocardial infarction (OR, 0.62; 95% credible intervals, 0.39-1.05) and weak evidence of an increase in major bleeding (OR, 1.66; 95% credible intervals, 0.89-3.09) associated with extended DAPT. Conclusions - In this meta-analysis, extended DAPT beyond 1 year prevented myocardial infarctions and increased major bleedings, but the strength of evidence for these effects was not strong. DAPT continuation beyond 1 year showed no effects on mortality.