title: Effect of statins on atrial fibrillation: collaborative meta-analysis of published and unpublished evidence from randomised controlled trials.
abstract: OBJECTIVE
  To examine whether statins can reduce the risk of atrial fibrillation.
  
  
  METHODS
  Meta-analysis of published and unpublished results from larger scale statin trials, with comparison of the findings against the published results from smaller scale or shorter duration studies.
  
  
  METHODS
  Medline, Embase, and Cochrane's CENTRAL up to October 2010. Unpublished data from longer term trials were obtained through contact with investigators.
  
  
  METHODS
  Randomised controlled trials comparing statin with no statin or comparing high dose versus standard dose statin; all longer term trials had at least 100 participants and at least six months' follow-up.
  
  
  RESULTS
  In published data from 13 short term trials (4414 randomised patients, 659 events), statin treatment seemed to reduce the odds of an episode of atrial fibrillation by 39% (odds ratio 0.61, 95% confidence interval 0.51 to 0.74; P < 0.001), but there was significant heterogeneity (P < 0.001) between the trials. In contrast, among 22 longer term and mostly larger trials of statin versus control (105,791 randomised patients, 2535 events), statin treatment was not associated with a significant reduction in atrial fibrillation (0.95, 0.88 to 1.03; P = 0.24) (P<0.001 for test of difference between the two sets of trials). Seven longer term trials of more intensive versus standard statin regimens (28,964 randomised patients and 1419 events) also showed no evidence of a reduction in the risk of atrial fibrillation (1.00, 0.90 to 1.12; P = 0.99).
  
  
  CONCLUSIONS
  The suggested beneficial effect of statins on atrial fibrillation from published shorter term studies is not supported by a comprehensive review of published and unpublished evidence from larger scale trials.
authors.affiliation: George Centre for Healthcare Innovation, University of Oxford, Oxford, UK. kazem.rahimi@cardiov.ox.ac.uk
authors.forename: Kazem
authors.initials: K
authors.lastname: Rahimi
authors.forename: Jonathan
authors.initials: J
authors.lastname: Emberson
authors.forename: Paul
authors.initials: P
authors.lastname: McGale
authors.forename: William
authors.initials: W
authors.lastname: Majoni
authors.forename: Amal
authors.initials: A
authors.lastname: Merhi
authors.forename: Folkert W
authors.initials: FW
authors.lastname: Asselbergs
authors.forename: Vera
authors.initials: V
authors.lastname: Krane
authors.forename: Peter W
authors.initials: PW
authors.lastname: Macfarlane
mesh_terms: D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000517:prevention & control*; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D017594:Publication Bias; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors