Systematic review and meta-analysis of the efficacy of statins in experimental stroke

Background and purpose Statins are postulated as candidate drugs for the treatment of acute stroke. The aim of this study was to critically appraise the evidence for the efficacy of statins administered after the onset of experimental focal cerebral ischemia. Methods We undertook a systematic review and metaanalysis of animal studies reporting the efficacy of any statin administered following middle cerebral artery occlusion. The primary outcome measure was infarct volume. Assessment of study quality and range of evidence were undertaken, and prespecified sub-group analyses were performed. Results Eighteen published studies describing outcome in 472 animals were identified. Statins reduced infarct volume by 11.2% (95% confidence interval 8.1% to 14.3%, P < 0.001) and improved the neurological severity score by 0.7 points (95% confidence interval 0.4 to 1.1, P < 0.0001). Efficacy was evident up to three-hours post-middle cerebral artery occlusion. Median study quality score was 7 of 13 (interquartile range, 4 to 11). No studies tested efficacy in aged, female, or hypertensive animals; or in species other than rodents. Conclusions These findings suggest that statins administered after middle cerebral artery occlusion have modest efficacy. Effects of potential sources of bias are considered likely to reduce the estimated effect from this review.