title: Comparison of two approaches of INR-follow-up and determinants of INR-stability.
abstract: BACKGROUND
  Patients with atrial fibrillation (AF) and treated with coumarins need a close follow-up of the international normalized ratio (INR)-values. This can be done by the general practitioner (GP) or by a haematologist in an outpatient hospital clinic.
  
  
  OBJECTIVE
  To compare both ways of follow-up and to investigate determinants of stable INR-patterns.
  
  
  METHODS
  Cross-sectional single-centre study in patients with AF treated at the UZ Brussel, a university hospital in Brussels. Of the 113 patients included in the study, 71 had their INR followed-up by their GP and 42 similar patients were followed-up by a haematologist. Data of these 113 patients were further analysed to identify possible determinants for stable INR-values.
  
  
  RESULTS
  The time in therapeutic range (TTR) did not significantly differ between both groups. However, patients in the GP-group had significantly more INR-values under 2.0 compared to patients from the haematologist-group (P =  0.044), whereas patients in the haematologist-group had significantly more INR-values above 3.0 compared to patients from the GP-group (P = 0.038). Reimbursement costs of both ways of follow-up were comparable, but the out-of-pocket costs for the patient were lower in the GP-group. The time since AF diagnosis was the only significant determinant predicting a higher TTR.
  
  
  CONCLUSIONS
  Both approaches of follow-up seem to lead to the same TTR, yielding no reason to advocate one approach above the other. However, the patient costs were lower when followed-up by the GP.
authors.forename: S
authors.initials: S
authors.lastname: Desmaele
authors.forename: A G
authors.initials: AG
authors.lastname: Dupont
authors.forename: K
authors.initials: K
authors.lastname: Putman
authors.forename: P
authors.initials: P
authors.lastname: Cornu
authors.forename: S
authors.initials: S
authors.lastname: Steurbaut
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000494:pharmacology; D001281:Atrial Fibrillation / Q000188:drug therapy*; D001530:Belgium; D003365:Costs and Cost Analysis; D003430:Cross-Sectional Studies; D016903:Drug Monitoring / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D058005:General Practitioners / Q000706:statistics & numerical data*; D006405:Hematology / Q000706:statistics & numerical data*; D006801:Humans; D019934:International Normalized Ratio / Q000191:economics / Q000379:methods / Q000706:statistics & numerical data; D008297:Male; D010044:Outpatient Clinics, Hospital / Q000706:statistics & numerical data; D013997:Time Factors; D014859:Warfarin / Q000494:pharmacology*
chemical_list: D000925:Anticoagulants; D014859:Warfarin
keywords: Anticoagulants,; Atrial fibrillation,; General practitioners,; Haematology; International normalised ratio,