title: Major haemorrhagic complications during oral anticoagulant therapy in a Danish population-based cohort.
abstract: OBJECTIVE
  To estimate the incidence of bleeding leading to death or hospital admission in out-patients treated with oral anticoagulants.
  
  
  METHODS
  Population-based historical cohort study 1 January 1992 to 31 September 1994.
  
  
  METHODS
  The County of North Jutland, Denmark (488,000 inhabitants).
  
  
  METHODS
  Six hundred and eighty-two consecutive patients commencing oral anticoagulant therapy.
  
  
  METHODS
  Fatal bleeding or bleeding demanding hospital admission.
  
  
  RESULTS
  In 756 treatment-years of follow-up, there were 45 major haemorrhagic events (6.0 per 100 treatment-years) in 42 patients, of which seven (0.9 per 100 treatment-years) were fatal. The risk of a first major haemorrhagic episode was highest during the first 90 days of treatment compared with duration above one year (incidence rate ratio, IRR, 1.9; 95% CI, 0.8-4.1). The rate was highest above the age of 60 years, 6.8 per 100 treatment-years, compared with 2.9 per 100 treatment-years below 60 years (IRR 2.3; 95% CI, 1.0-5.6). The rate for a bleeding event was slightly higher in females than in males (IRR 1.3; 95% CI, 0.7-2.3), but did not vary according to type of anticoagulant drug.
  
  
  CONCLUSIONS
  The reported rates of major bleeding in this routine community setting implied a higher bleeding risk than was found in randomized trials or when patients are monitored in specialist anticoagulation clinics.
authors.affiliation: Danish Epidemiology Science Centre, University of Aarhus, Denmark.
authors.forename: F H
authors.initials: FH
authors.lastname: Steffensen
authors.forename: K
authors.initials: K
authors.lastname: Kristensen
authors.forename: E
authors.initials: E
authors.lastname: Ejlersen
authors.forename: J F
authors.initials: JF
authors.lastname: Dahlerup
authors.forename: H T
authors.initials: HT
authors.lastname: Sørensen
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000009:adverse effects*; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced* / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016012:Poisson Distribution; D012042:Registries; D012307:Risk Factors; D017678:Sex Distribution
chemical_list: D000925:Anticoagulants