Effectiveness and Safety of Apixaban, Dabigatran, and Rivaroxaban Versus Warfarin in Patients With Nonvalvular Atrial Fibrillation and Previous Stroke or Transient Ischemic Attack. Issue 8 (August 2017)

• Record Type: Journal Article
• Authors: Coleman, Craig I.; Peacock, W. Frank; Bunz, Thomas J.; Alberts, Mark J.
• Is Part Of: Stroke. Volume 48:Issue 8(2017)
• Publication Date: 2017-08
• Subjects: anticoagulants -- atrial fibrillation -- dabigatran -- rivaroxaban -- stroke; Cerebrovascular disease -- Periodicals; Cerebral circulation -- Periodicals; 616.81
• DOI: 10.1161/STROKEAHA.117.017474
• Languages: English
• ISSNs: 0039-2499

Abstract

Abstract : Background and Purpose—: Limited real-world data exist comparing each non–vitamin K antagonist oral anticoagulant (NOAC) to warfarin in patients with nonvalvular atrial fibrillation who have had a previous ischemic stroke or transient ischemic attack. Methods—: Using MarketScan claims from January 2012 to June 2015, we identified adults newly initiated on oral anticoagulation, with ≥2 diagnosis codes for nonvalvular atrial fibrillation, a history of previous ischemic stroke/transient ischemic attack, and ≥180 days of continuous medical and prescription benefits before anticoagulation initiation. Three analyses were performed comparing 1:1 propensity score–matched cohorts of apixaban versus warfarin (n=2514), dabigatran versus warfarin (n=1962), and rivaroxaban versus warfarin (n=5208). Patients were followed until occurrence of a combined end point of ischemic stroke and intracranial hemorrhage (ICH) or major bleed, switch/discontinuation of index oral anticoagulation, insurance disenrollment, or end of follow-up. Mean follow-up was 0.5 to 0.6 years for all matched cohorts. Results—: Using Cox regression, neither apixaban nor dabigatran reduced the combined primary end point of ischemic stroke or ICH (hazard ratio [HR], 0.70; 95% confidence interval [CI], 0.33–1.48 and HR, 0.53; 95% CI, 0.26–1.07) and had nonsignificant effect on hazards of major bleeding (HR, 0.79; 95% CI, 0.38–1.64 and HR, 0.58; 95% CI, 0.26–1.27) versus warfarin. Rivaroxaban reduced the combined end point of ischemic stroke or ICH (HR, 0.45; 95% CI, 0.29–0.72) without an effect on major bleeding (HR, 1.07; 95% CI, 0.71–1.61). ICH occurred at rates of 0.16 to 0.61 events per 100 person-years in the 3 NOAC analyses, with no significant difference for any NOAC versus warfarin. Conclusions—: Results from our study of the 3 NOACs versus warfarin in nonvalvular atrial fibrillation patients with a previous history of stroke/transient ischemic attack are relatively consistent with their respective phase III trials and previous stroke/transient ischemic attack subgroup analyses. All NOACs seemed no worse than warfarin in respect to ischemic stroke, ICH, or major bleeding risk. Abstract : Supplemental Digital Content is available in the text.