title: Comparison of treatment persistence with different oral anticoagulants in patients with atrial fibrillation.
abstract: OBJECTIVE
  Oral anticoagugulants (OACs) effectively reduce the risk for ischemic stroke in patients with atrial fibrillation (AF), but undertreatment and poor persistence with treatment are important problems. NOACs now provide alternatives to warfarin. This study compares the persistence with presently available antithrombotic treatments in AF patients with a CHA2DS2VASc score ≥2.
  
  
  METHODS
  All first claims of either warfarin (n = 9969), dabigatran (n = 2701), rivaroxaban (n = 2074), apixaban (n = 1352), or aspirin (n = 4540) from April 2011 until December 2014, in individuals with non-valvular AF and CHA2DS2VASc scores of 2-9, were identified in the administrative health data register (VAL) of the Stockholm region (2.1 million inhabitants). Prescription claims were analyzed with and without multivariate analysis in relation to age, sex, prescriber category, prior OAC treatment, number of drugs, and death.
  
  
  RESULTS
  The overall persistence with any OAC was 88.2% (CI 87.5-88.9) at 1 year and 82.9% (CI 81.8-83.9) at 2 years. After 1 year, the crude persistence was 85.0% (CI 84.2-85.9) with warfarin, 85.9% (CI 81.8-90.1) with apixaban, 74.4% (CI 72.3-76.5) with dabigatran, and 77.4% (CI 74.6-80.2) with rivaroxaban. Multivariate analysis confirmed significantly higher persistence with warfarin and apixaban than with dabigatran or rivaroxaban. The adherence (proportion of days covered >80%) was above 90% for all NOACs; significantly higher with rivaroxaban compared to dabigatran (p < 0.001), but not compared to apixaban (p = 0.14).
  
  
  CONCLUSIONS
  After 2 years, the persistence with any anticoagulant treatment was high in patients with non-valvular AF. Our results indicate better persistence with warfarin and apixaban than with dabigatran or rivaroxaban in regular care.
authors.affiliation: Department of Medicine Solna, Clinical Epidemiology/Clinical Pharmacology Unit, Karolinska Institutet/Karolinska University Hospital, Solna, 171 76, Sweden. tomas.forslund@sll.se.|Public Healthcare Services Committee, Department of Healthcare Development, Stockholm County Council, Stockholm, Sweden. tomas.forslund@sll.se.
authors.forename: Tomas
authors.initials: T
authors.lastname: Forslund
authors.affiliation: Department of Medicine Solna, Clinical Epidemiology/Clinical Pharmacology Unit, Karolinska Institutet/Karolinska University Hospital, Solna, 171 76, Sweden.|Public Healthcare Services Committee, Department of Healthcare Development, Stockholm County Council, Stockholm, Sweden.
authors.forename: Björn
authors.initials: B
authors.lastname: Wettermark
authors.affiliation: Department of Medicine Solna, Clinical Epidemiology/Clinical Pharmacology Unit, Karolinska Institutet/Karolinska University Hospital, Solna, 171 76, Sweden.
authors.forename: Paul
authors.initials: P
authors.lastname: Hjemdahl
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000627:therapeutic use*; D001241:Aspirin / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000188:drug therapy*; D000069604:Dabigatran / Q000627:therapeutic use; D057915:Drug Substitution; D005260:Female; D006801:Humans; D008297:Male; D011720:Pyrazoles / Q000627:therapeutic use; D011728:Pyridones / Q000627:therapeutic use; D000069552:Rivaroxaban / Q000627:therapeutic use; D014859:Warfarin / Q000627:therapeutic use; D016903:Drug Monitoring
chemical_list: D000925:Anticoagulants; D011720:Pyrazoles; D011728:Pyridones; C522181:apixaban; D014859:Warfarin; D000069552:Rivaroxaban; D000069604:Dabigatran; D001241:Aspirin
keywords: Adherence; Anticoagulant; Antithrombotic; Atrial fibrillation; NOAC; Persistence