Safety and efficacy of drug-eluting and bare metal stents: comprehensive meta-analysis of randomized trials and observational studies

Background — The safety and efficacy of drug-eluting stents (DES) among more generalized “real-world” patients than those enrolled in pivotal randomized controlled trials (RCTs) are controversial. We sought to perform a meta-analysis of DES studies to estimate the relative impact of DES versus bare metal stents (BMS) on safety and efficacy end points, particularly for non–Food and Drug Administration–labeled indications.

Methods and Results — Comparative DES versus BMS studies published or presented through February 2008 with ≥100 total patients and reporting mortality data with cumulative follow-up of ≥1 year were identified. Data were abstracted from studies comparing DES with BMS; original source data were used when available. Data from 9470 patients in 22 RCTs and from 182 901 patients in 34 observational studies were included. RCT and observational data were analyzed separately. In RCTs, DES (compared with BMS) were associated with no detectable differences in overall mortality (hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.81 to 1.15; P=0.72) or myocardial infarction (HR, 0.95; 95% CI, 0.79 to 1.13; P=0.54), with a significant 55% reduction in target vessel revascularization (HR, 0.45; 95% CI, 0.37 to 0.54; P<0.0001); point estimates were slightly lower in off-label compared with on-label analyses. In observational studies, DES were associated with significant reductions in mortality (HR, 0.78; 95% CI, 0.71 to 0.86), myocardial infarction (HR, 0.87; 95% CI, 0.78 to 0.97), and target vessel revascularization (HR, 0.54; 95% CI, 0.48 to 0.61) compared with BMS.

Conclusions — In RCTs, no significant differences were observed in the long-term rates of death or myocardial infarction after DES or BMS use for either off-label or on-label indications. In real-world nonrandomized observational studies with greater numbers of patients but the admitted potential for selection bias and residual confounding, DES use was associated with reduced death and myocardial infarction. Both RCTs and observational studies demonstrated marked and comparable reductions in target vessel revascularization with DES compared with BMS. These data in aggregate suggest that DES are safe and efficacious in both on-label and off-label use but highlight differences between RCT and observational data comparing DES and BMS.