title: Bleeding risk in 'real world' patients with atrial fibrillation: comparison of two established bleeding prediction schemes in a nationwide cohort.
abstract: BACKGROUND
  Oral anticoagulation (OAC) in patients with atrial fibrillation (AF) is a double-edged sword, because it decreases the risk of stroke at the cost of an increased risk of bleeding. We compared the performance of a new bleeding prediction scheme, HAS-BLED, with an older bleeding prediction scheme, HEMORR(2)HAGES, in a cohort of 'real-world' AF patients.
  
  
  METHODS
  By individual-level-linkage of nationwide registers, we identified all patients (n = 118,584) discharged with non-valvular AF in Denmark during the period 1997-2006, with and without OAC. Major bleeding rates during 1 year of follow-up were determined, and the predictive capabilities of the two schemes were compared by c-statistics. The risk of bleeding associated with individual risk factors composing HAS-BLED was estimated using Cox proportional-hazard analyses.
  
  
  RESULTS
  Of AF patients receiving OAC (n = 44,771), 34.8% and 47.3% were categorized as 'low bleeding risk' by HAS-BLED and HEMORR(2)HAGES, respectively, and the bleeding rates per 100 person-years were 2.66 (95% confidence interval [CI], 2.40-2.94) and 3.06 (2.83-3.32), respectively. C-statistics for the two schemes were 0.795 (0.759-0.829) and 0.771 (0.733-0.806), respectively. The risk factors composing HAS-BLED were associated with varying risks, with a history of bleeding (hazard ratio [HR] 2.98; 95% CI 2.68-3.31) and being elderly (HR 1.93; 95% CI 1.71-2.18) being associated with the highest risks. Comparable results were found in AF patients not receiving OAC (n = 77,813).
  
  
  CONCLUSIONS
  In an unselected nationwide cohort of hospitalized patients with atrial fibrillation, the HAS-BLED score performs similarly to HEMORR(2)HAGES in predicting bleeding risk but HAS-BLED is much simpler and easier to use in everyday clinical practise.
authors.affiliation: Department of Cardiology, Copenhagen University Hospital Gentofte, Hellerup, Denmark. jo@heart.dk
authors.forename: J B
authors.initials: JB
authors.lastname: Olesen
authors.forename: G Y H
authors.initials: GY
authors.lastname: Lip
authors.forename: P R
authors.initials: PR
authors.lastname: Hansen
authors.forename: J
authors.initials: J
authors.lastname: Lindhardsen
authors.forename: O
authors.initials: O
authors.lastname: Ahlehoff
authors.forename: C
authors.initials: C
authors.lastname: Andersson
authors.forename: P
authors.initials: P
authors.lastname: Weeke
authors.forename: M L
authors.initials: ML
authors.lastname: Hansen
authors.forename: G H
authors.initials: GH
authors.lastname: Gislason
authors.forename: C
authors.initials: C
authors.lastname: Torp-Pedersen
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects*; D001281:Atrial Fibrillation / Q000150:complications / Q000188:drug therapy*; D016009:Chi-Square Distribution; D003718:Denmark; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D020521:Stroke / Q000209:etiology / Q000517:prevention & control*; D013997:Time Factors
chemical_list: D000925:Anticoagulants