Thirty-two studies (71,005 patients; range 40 to 17,120) were included in the review; trial duration ranged from seven days to six years. Twenty-eight compared statins with no statins (61,773 patients) and four compared different statin regimens (9,232 patients). The Jadad score was 2 in six RCTs, 3 in six RCTs, 4 in five RCTs, and 5 in 15 RCTs.
Overall, the use of statins was significantly associated with a decreased risk of atrial fibrillation compared with controls (OR 0.69, 95% CI 0.57 to 0.83; 28 RCTs; Ι² 70%); statistical heterogeneity was reduced when the analysis was restricted to postoperative patients (OR 0.37, 95% CI 0.28 to 0.51; 10 RCTs; Ι² 0%).
Statin therapy was not beneficial for the primary prevention of atrial fibrillation (OR 1.00, 95% CI 0.86 to 1.15; nine RCTs; Ι² 52%), but was for secondary prevention (OR 0.57, 95% CI 0.36 to 0.91; 10 RCTs; Ι² 70%). There was no evidence of a reduction in the risk of atrial fibrillation more intensive statin regimens (OR 1.01, 95% CI 0.77 to 1.32; four RCTs; Ι² 31%).
The authors stated that they could not exclude the possibility of a publication bias.