title: Early adoption of dabigatran and its dosing in US patients with atrial fibrillation: results from the outcomes registry for better informed treatment of atrial fibrillation.
abstract: BACKGROUND
  Dabigatran is a novel oral anticoagulant approved for thromboprophylaxis in atrial fibrillation. Adoption patterns of this new agent in community practice are unknown.
  
  
  RESULTS
  We studied patterns of dabigatran use among patients enrolled in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF) Registry between June 2010 and August 2011 and followed for 12 months. Among 9974 atrial fibrillation patients included, 1217 (12%) were treated with dabigatran during the study. Overall, patients receiving dabigatran were younger (median age 72 versus 75 years, P<0.0001), more likely to be white (92% versus 89%, P=0.005), more likely to have private insurance (33% versus 25%, P<0.0001), and less likely to have prior cardiovascular disease (4% versus 33%, P<0.0001). They had more new-onset atrial fibrillation (8.8% versus 4.1%, P<0.0001), lower CHADS2 scores (estimated risk based on the presence of congestive heart failure, hypertension, aged ≥75 years, diabetes mellitus, and prior stroke or transient ischemic attack; mean 2.0 versus 2.3, P<0.0001), and lower Anticoagulation and Risk Factors in Atrial Fibrillation scores (mean 2.4 versus 2.8, P<0.0001). More than half (n=14/25, 56%) of patients with severe kidney disease were not prescribed reduced dosing, whereas 10% (n=91/920) with preserved renal function received lower dosing. Among patients not on dabigatran at baseline, 8% had dabigatran initiated during follow-up. Patient education was significantly associated with switching from warfarin to dabigatran (adjusted odds ratio for postgraduate 1.73, P=0.007), whereas antiarrhythmic drug use significantly correlated with de novo adoption of dabigatran (adjusted odds ratio 2.4, P<0.0001).
  
  
  CONCLUSIONS
  Patients receiving dabigatran were younger and at a lower risk of stroke and bleeding. Patients appeared to drive switching from warfarin, whereas clinical characteristics influenced de novo start of dabigatran. These data suggest cautious early uptake of dabigatran, and more careful attention to dosing adjustments is warranted.
  
  
  BACKGROUND
  Clinicaltrials.gov. Unique identifier: NCT01165710.
authors.affiliation: Duke University Medical Center, Durham, NC.
authors.forename: Benjamin A
authors.initials: BA
authors.lastname: Steinberg
authors.forename: Dajuanicia N
authors.initials: DN
authors.lastname: Holmes
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Piccini
authors.forename: Jack
authors.initials: J
authors.lastname: Ansell
authors.forename: Paul
authors.initials: P
authors.lastname: Chang
authors.forename: Gregg C
authors.initials: GC
authors.lastname: Fonarow
authors.forename: Bernard
authors.initials: B
authors.lastname: Gersh
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Mahaffey
authors.forename: Peter R
authors.initials: PR
authors.lastname: Kowey
authors.forename: Michael D
authors.initials: MD
authors.lastname: Ezekowitz
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Singer
authors.forename: Laine
authors.initials: L
authors.lastname: Thomas
authors.forename: Eric D
authors.initials: ED
authors.lastname: Peterson
authors.forename: Elaine M
authors.initials: EM
authors.lastname: Hylek
mesh_terms: D000284:Administration, Oral; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects; D001281:Atrial Fibrillation / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology; D001562:Benzimidazoles / Q000008:administration & dosage* / Q000009:adverse effects; D016009:Chi-Square Distribution; D015897:Comorbidity; D000069604:Dabigatran; D054796:Drug Dosage Calculations; D057915:Drug Substitution; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010353:Patient Education as Topic; D010818:Practice Patterns, Physicians' / Q000639:trends*; D016016:Proportional Hazards Models; D012042:Registries; D012307:Risk Factors; D012959:Socioeconomic Factors; D020521:Stroke / Q000453:epidemiology / Q000517:prevention & control; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D015091:beta-Alanine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*
chemical_list: D000925:Anticoagulants; D001562:Benzimidazoles; D015091:beta-Alanine; D000069604:Dabigatran
keywords: anticoagulant; atrial fibrillation; dabigatran; dosing; pharmacoepidemiology