title: Anemia predicts thromboembolic events, bleeding complications and mortality in patients with atrial fibrillation: insights from the RE-LY trial.
abstract: BACKGROUND
  Anemia may predispose to thromboembolic events or bleeding in anticoagulated patients with atrial fibrillation (AF).
  
  
  OBJECTIVE
  To investigate whether anemia is associated with thromboembolic events and bleeding in patients with AF.
  
  
  METHODS
  We retrospectively analyzed the RE-LY trial database, which randomized 18 113 patients with AF and a risk of stroke to receive dabigatran or warfarin for a median follow-up of 2 years. Cox regression analysis was used to determine whether anemia predicted cardiovascular events and bleeding complications in these patients.
  
  
  RESULTS
  Anemia was present in 12% of the population at baseline, and the presence of anemia was associated with a higher risk of thromboembolic cardiovascular events, including the composite endpoint of all-cause mortality or myocardial infarction (adjusted hazard ratio [HR] 1.50, 95% confidence interval [CI] 1.32-1.71) and the primary RE-LY outcome of stroke or systemic embolism (adjusted HR 1.41, 95% CI 1.12-1.78). Anemia was also associated with a higher risk of major bleeding complications (adjusted HR 2.14, 95% CI 1.87-2.46) and discontinuation of anticoagulants (adjusted HR 1.40, 95% CI 1.28-1.79). The association between anemia and outcome was similar irrespective of cardiovascular comorbidities, randomized treatment allocation, or prior use of warfarin. The incidence of events was lower in patients with transient anemia than in patients in whom anemia was sustained (adjusted HR 0.66, 95% CI 0.49-0.91).
  
  
  CONCLUSIONS
  Anemia is associated with an increased risk of thromboembolic events, bleeding complications and mortality in anticoagulated patients with AF. These findings suggest that patients with anemia should be monitored closely during all types of anticoagulant treatment.
authors: Department of Cardiology, University Medical Center Groningen, Groningen, The Netherlands.
authors: B D
authors: BD
authors: Westenbrink
authors: M
authors: M
authors: Alings
authors: S J
authors: SJ
authors: Connolly
authors: J
authors: J
authors: Eikelboom
authors: M D
authors: MD
authors: Ezekowitz
authors: J
authors: J
authors: Oldgren
authors: S
authors: S
authors: Yang
authors: J
authors: J
authors: Pongue
authors: S
authors: S
authors: Yusuf
authors: L
authors: L
authors: Wallentin
authors: W H
authors: WH
authors: van Gilst
mesh_terms: D000368:Aged; D000740:Anemia / Q000150:complications* / Q000453:epidemiology; D001281:Atrial Fibrillation / Q000150:complications / Q000401:mortality / Q000503:physiopathology*; D005260:Female; D006470:Hemorrhage / Q000150:complications*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D013923:Thromboembolism / Q000150:complications*
keywords: anemia; anticoagulants; bleeding; mortality; thromboembolism