Effect of statins on atrial fibrillation after cardiac surgery: A duration- and dose-response meta-analysis

Objective: This meta-analysis of randomized, controlled trials evaluated effects of statins on postoperative atrial fibrillation risk after cardiac surgery. Methods: Randomized, controlled trials evaluating statins in cardiac surgery were selected from MEDLINE (1996-August 2009), Cochrane CENTRAL Register, and manual review of references without any language restrictions. End points examined included postoperative atrial fibrillation, intensive care unit stay, and total hospital stay. Meta-regression analyses were conducted to determine whether statins' effects were duration or dose dependent. A random-effects model was used in all instances. Results: Eight trials (n = 774) were identified and subjected to meta-analysis. Statins reduced postoperative atrial fibrillation risk (relative risk 0.57, 95% confidence interval 0.45-0.72, P < .0001, risk difference -0.14, 95% confidence interval -0.20 to -0.08, P < .0001, number needed to treat 8) and total hospital stay (weighted mean difference -0.66 days, 95% confidence interval -1.01 to -0.30 days, P = .0004) relative to placebo. Intensive care unit stay was also reduced (weighted mean difference -0.17 days, 95% confidence interval -0.37 to 0.03 days, P = .09) but did not meet prespecified criteria for statistical significance. Metaregression analysis revealed association between duration of preoperative statin prophylaxis and postoperative atrial fibrillation risk reduction (3% reduction per day, P = .008). No association was found between statin dose used and risk reduction (P = .47). Conclusions: Evidence suggests that statins are associated with reduced risk of postoperative atrial fibrillation and shorter hospital stay after cardiac surgery and that earlier therapy results in more profound benefit. (J Thorac Cardiovasc Surg 2010;140:364-72)