title: New oral anticoagulants are not superior to warfarin in secondary prevention of stroke or transient ischemic attacks, but lower the risk of intracranial bleeding: insights from a meta-analysis and indirect treatment comparisons.
abstract: OBJECTIVE
  Patients with Atrial Fibrillation (AF) and prior stroke are classified as high risk in all risk stratification schemes. A systematic review and meta-analysis was performed to compare the efficacy and safety of New Oral Anticoagulants (NOACs) to warfarin in patients with AF and previous stroke or transient ischemic attack (TIA).
  
  
  METHODS
  Three randomized controlled trials (RCTs), including total 14527 patients, comparing NOACs (apixaban, dabigatran and rivaroxaban) with warfarin were included in the analysis. Primary efficacy endpoint was ischemic stroke, and primary safety endpoint was intracranial bleeding. Random-effects models were used to pool efficacy and safety data across RCTs. RevMan and Stata software were used for direct and indirect comparisons, respectively.
  
  
  RESULTS
  In patients with AF and previous stroke or TIA, effects of NOACs were not statistically different from that of warfarin, in reduction of stroke (Odds Ratio [OR] 0.86, 95% confidence interval [CI] 0.73- 1.01), disabling and fatal stroke (OR 0.85, 95% CI 0.71-1.04), and all-cause mortality (OR 0.90, 95% CI 0.79 -1.02). Randomization to NOACs was associated with a significantly lower risk of intracranial bleeding (OR 0.42, 95% CI 0.25-0.70). There were no major differences in efficacy between apixaban, dabigatran (110 mg BID and 150 mg BID) and rivaroxaban. Major bleeding was significantly lower with apixaban and dabigatran (110 mg BID) compared with dabigatran (150 mg BID) and rivaroxaban.
  
  
  CONCLUSIONS
  NOACs may not be more effective than warfarin in the secondary prevention of ischemic stroke in patients with a prior history of cerebrovascular ischemia, but have a lower risk of intracranial bleeding.
authors.affiliation: Department of Medicine, New York Medical College, Metropolitan Hospital Center, New York, New York, United States of America.
authors.forename: Partha
authors.initials: P
authors.lastname: Sardar
authors.forename: Saurav
authors.initials: S
authors.lastname: Chatterjee
authors.forename: Wen-Chih
authors.initials: WC
authors.lastname: Wu
authors.forename: Edgar
authors.initials: E
authors.lastname: Lichstein
authors.forename: Joydeep
authors.initials: J
authors.lastname: Ghosh
authors.forename: Shamik
authors.initials: S
authors.lastname: Aikat
authors.forename: Debabrata
authors.initials: D
authors.lastname: Mukherjee
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use*; D005260:Female; D006470:Hemorrhage / Q000517:prevention & control*; D006801:Humans; D020300:Intracranial Hemorrhages / Q000517:prevention & control*; D002546:Ischemic Attack, Transient / Q000188:drug therapy / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic; D012306:Risk; D055502:Secondary Prevention / Q000379:methods; D020521:Stroke / Q000188:drug therapy / Q000517:prevention & control*; D014859:Warfarin / Q000627:therapeutic use*
chemical_list: D000925:Anticoagulants; D014859:Warfarin