Eight RCTs (n=27,758) were included .
There was a trend towards reduced 30-day mortality (OR 0.92, 95% CI: 0.84, 1.01, p=0.08; NNT 167) and a significant reduction in the risk of reinfarction at 30 days (OR 0.65, 95% CI: 0.58, 0.74, p<0.0001; NNT 62) among patients treated with LMWH compared with those treated with UFH. There was a higher risk of major bleeding complications among those treated with LMWH than among those treated with UFH (OR 1.37, 95% CI: 1.16, 1.61, p<0.001). There was no evidence of heterogeneity for any of the analyses.
There was no association between patient risk profile and benefits in mortality (p=0.11).
The results of the assessment of publication bias were not reported.