Eleven RCTs (5,137 participants) were included. Of these three (1,408 participants) assessed the use of nonpolymer paclitaxel-eluting stents. These three were excluded from the main analysis and were analysed separately.
The mean quality scores were 0.54 to 0.87 for single studies, 0.62 to 0.94 for study protocol, and 0.41 to 0.75 for data analysis and presentation.
For all the studies combined (8 RCTs), there was a decrease in MACE in the DES group in comparison with bare metal stents (RR 0.4, 95% CI: 0.33, 0.49). For individual outcomes, DES reduced the need for percutaneous revascularisation (RR 0.3, 95% CI: 0.22, 0.4) and CABG (RR 0.54, 95% CI: 0.32, 0.89). There were no statistically significant differences for other outcomes: death (RR 1.11, 95% CI: 0.58, 2.10), MI (RR 0.79, 95% CI: 0.57, 1.09) or thrombosis (RR 0.70, 95% CI: 0.30, 1.63).
The results were similar for meta-analyses of studies analysed by type of drug (paclitaxel or sirolimus), although the protective effect appeared greater with sirolimus-eluting stents; the RR for MACE was 0.33 (95% CI: 0.26, 0.42) with sirolimus and 0.52 (95% CI: 0.41, 0.65) with paclitaxel.
The results for nonpolymer paclitaxel-eluting stents showed no statistically significant benefit in comparison with bare metal stents for any of the outcomes; for MACE, the RR was 0.79 (95% CI: 0.60, 1.03).
The authors stated that there was no evidence of statistical heterogeneity. Regression meta-analyses showed sirolimus to be superior to paclitaxel in decreasing MACE. None of the other factors examined showed any significant influence on effect.