Twelve RCTs were included in the review (43,674 participants). Eight trials scored 9 out of 9 points on the quality scale, one scored 6 and three scored fewer than 6 points. There was no evidence of publication bias.
All trials
Compared to placebo, glycoprotein IIb/IIIa inhibitors reduced the odds of death or miocardial infarction at 30 days (OR 0.89, 95% CI 0.83 to 0.95). Mortality rates were not significantly different between groups (OR 0.93, 95% CI 0.83 to 1.05). Compared to placebo, glycoprotein IIb/IIIa inhibitors increased the risk of major and non-major bleeding (OR 1.23, 95% CI 1.02 to 1.48) and transfusion (OR 1.27, 95% CI 1.17 to 1.38).
Upstream versus placebo only (seven trials, 24,031 participants)
Compared to placebo, glycoprotein IIb/IIIa inhibitors reduced the odds of death or miocardial infarction at 30 days (OR 0.88, 95% CI 0.81 to 0.95). Mortality rates were not significantly different between groups (OR 0.89, 95% CI 0.76 to 1.03). Major bleeding increased with the use of glycoprotein IIb/IIIa inhibitors (OR 1.17, 95% CI 0.88 to 1.54) as did transfusion (OR 1.25, 95% CI 1.13 to 1.39)
Upstream versus delayed use (five trials, 19,643 participants)
Compared to placebo, glycoprotein IIb/IIIa inhibitors reduced the odds of death or miocardial infarction at 30 days but were not statistically significantly different (OR 0.91, 95% CI 0.82 to 1.01). Mortality rates were not significantly different between groups (OR 1.00, 95% CI 0.81 to 1.23). Major bleeding increased with the use of glycoprotein IIb/IIIa inhibitors (OR 1.34, 95% CI 1.10 to 1.63) as did transfusion (OR 1.31, 95% CI 1.14 to 1.49).
Sensitivity analysis excluding lower quality scores did not alter efficacy findings. Statistically significant heterogeneity was found for major and non major bleeding when all trials were combined.