title: Adequacy of anticoagulation in patients with atrial fibrillation coming to a hospital.
abstract: OBJECTIVE
  To evaluate the adequacy of anticoagulation in patients with atrial fibrillation (AF) coming to a hospital.
  
  
  METHODS
  Retrospective medical record review.
  
  
  METHODS
  Tertiary care hospital.
  
  
  METHODS
  Consecutive patients with a history of AF who had been prescribed warfarin and who had the international normalized ratio (INR) measured when they arrived at the hospital. Those who developed AF as a complication during hospitalization were excluded.
  
  
  RESULTS
  Of 1085 patients, 375 (mean age 73 yrs, 56.3% men) were eligible for further evaluation. Most had nonvalvular AF; in 44.5% the INR was subtherapeutic, in 36.5% it was therapeutic, and in 18.9% it was supratherapeutic. Patients admitted for any thromboembolic event and for ischemic stroke were significantly more likely to have subtherapeutic INRs.
  
  
  CONCLUSIONS
  It is well documented in the literature that warfarin is underprescribed, but our results suggest that even in treated patients, about half are inadequately protected from thromboembolism.
authors.affiliation: Division of Cardiology, University of Alberta, Edmonton, Canada.
authors.forename: T J
authors.initials: TJ
authors.lastname: Bungard
authors.forename: M L
authors.initials: ML
authors.lastname: Ackman
authors.forename: G
authors.initials: G
authors.lastname: Ho
authors.forename: R T
authors.initials: RT
authors.lastname: Tsuyuki
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D000925:Anticoagulants / Q000008:administration & dosage*; D001281:Atrial Fibrillation / Q000188:drug therapy*; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D019934:International Normalized Ratio / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D010361:Patients / Q000706:statistics & numerical data; D012189:Retrospective Studies; D020521:Stroke / Q000517:prevention & control*; D013923:Thromboembolism / Q000517:prevention & control*; D014859:Warfarin / Q000008:administration & dosage*
chemical_list: D000925:Anticoagulants; D014859:Warfarin