Updated evidence on early statin therapy for acute coronary syndromes: Meta-analysis of 18 randomized trials involving over 14,000 patients

BACKGROUND: The short-term effects of early statin therapy in acute coronary syndromes (ACS) on clinical outcomes remain unclear. Our objective was to update the evidence on patient relevant outcomes from all randomized trials comparing early statin therapy with placebo or usual care at 1 and 4 months following ACS. METHODS: We performed a systematic review and meta-analysis of randomized trials that compared statins to control, initiated within 14 days after onset of ACS and with minimal follow-up of 30 days. Data were extracted in duplicate and analyzed by a random effects model. Investigators from individual trials contributed additional data where needed. RESULTS: A total of 18 trials involving 14,303 patients with ACS were included in the meta-analysis. We found no evidence for further trials on the topic. Risk ratios for the combined endpoint of death, myocardial infarction, and stroke of early statin therapy compared to control were 0.93 (95% confidence interval [CI], 0.80-1.08; P=0.34) at 1 month and 0.93 (95% CI, 0.81-1.06; P=0.27) at 4 months following ACS. There were favorable trends related to statin use for all individual secondary endpoints but there was no statistically significant risk reduction except for unstable angina with a risk ratio of 0.76 (95% CI, 0.59-0.96; P=0.02) at 4 months following ACS. CONCLUSIONS: Initiation of statin therapy within 14 days following ACS results in directionally favorable but non-significant reduction in death, myocardial infarction, or stroke up to 4 months, and significant reduction in the occurrence of unstable angina at 4 months following ACS.