title: Warfarin Treatment and Outcomes of Patients With Atrial Fibrillation in Rural and Urban Settings.
abstract: BACKGROUND
  Warfarin is an effective agent in the prevention of stroke in patients with atrial fibrillation (AF). However, it requires close monitoring with regular visits to health care facilities. To date, it is unknown whether there is a difference in warfarin utilization and outcomes between urban and rural settings.
  
  
  METHODS
  We used administrative databases to compare warfarin utilization patterns and stroke and major bleeding outcomes in rural and urban settings in a population-based cohort study of patients ≥ 65 years admitted to hospital with a diagnosis of AF in the province of Quebec, Canada, from 1999 to 2007. Patients' postal codes were used to differentiate between rural and urban settings.
  
  
  RESULTS
  The cohort comprised 18,198 rural (21.8%) and 65,315 urban (78.2%) patients, with similar mean age of 79 years and a similar burden of comorbidities. Overall, there was marked underutilization of warfarin in both rural and urban settings. Warfarin-filled prescription rates were slightly higher in the rural setting (adjusted OR: 1.16, 95% CI: 1.12-1.20). In multivariable Cox regression analyses, the risk for stroke and major bleeding in rural settings was similar to that in urban settings (stroke: adjusted HR: 1.01, 95% CI: 0.95-1.09; major bleeding: adjusted HR: 1.03, 95% CI: 0.95-1.12).
  
  
  CONCLUSIONS
  Patients in rural settings were slightly more likely to fill a prescription for warfarin, but they experienced similar stroke and major bleeding rates to their urban counterparts.
authors.affiliation: Division of Clinical Epidemiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Meytal
authors.initials: M
authors.lastname: Avgil Tsadok
authors.affiliation: Department of Pharmacy Practice and Administration, College of Pharmacy, Western University of Health Sciences, Pomona, California.|Institute for Clinical Evaluative Sciences, Toronto, Canada.|Department of Health Policy, Management and Evaluation, Faculty of Medicine, University of Toronto, Toronto, Canada.|University Health Network, Toronto, Canada.
authors.forename: Cynthia A
authors.initials: CA
authors.lastname: Jackevicius
authors.affiliation: Division of Cardiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Vidal
authors.initials: V
authors.lastname: Essebag
authors.affiliation: Division of Cardiology, Jewish General Hospital, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Eisenberg
authors.affiliation: Division of Clinical Epidemiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Elham
authors.initials: E
authors.lastname: Rahme
authors.affiliation: Division of Clinical Epidemiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Louise
authors.initials: L
authors.lastname: Pilote
mesh_terms: D000368:Aged; D000553:Ambulatory Care / Q000706:statistics & numerical data; D000925:Anticoagulants / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000188:drug therapy* / Q000453:epidemiology*; D016001:Confidence Intervals; D004363:Drug Utilization; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012424:Rural Population / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology; D014505:Urban Population / Q000706:statistics & numerical data*; D014859:Warfarin / Q000627:therapeutic use*
chemical_list: D000925:Anticoagulants; D014859:Warfarin
keywords: atrial fibrillation; observational study; stroke prevention; utilization of health services; warfarin