Reasons for hospitalization and risk of mortality in patients with atrial fibrillation treated with dabigatran or warfarin in the Randomized Evaluation of Long-term Anticoagulation Therapy (RE-LY) trial

Aims Hospitalizations are common among patients with atrial fibrillation. This article aimed to analyse the causes and consequences of hospitalizations occurring during the Randomized Evaluation of Long-term Anticoagulation Therapy (RE-LY) trial. Methods and results The RE-LY database was used to evaluate predictors of hospitalization using multivariate regression modelling. The relationship between hospitalization and subsequent major adverse cardiac events was evaluated in a time dependent Cox proportional-hazard modelling. Of the 18 113 patients in RE-LY, 7200 (39.8%) were hospitalized at least once during a mean follow-up of 2 years. First hospitalization rates were 2312 (39.5%) for dabigatran etexilate (DE) 110, 2430 (41.6%) for DE 150, and 42.6% (N = 2458) for warfarin. Hospitalization was associated with post-discharge death [absolute event rate 9.1% vs. 2.2%; adjusted hazard ratio (HR) 3.6, 95% confidence interval (CI) 3.2-4.0, P < 0.0001], vascular death (adjusted HR 2.9, 95% CI 2.5-3.3, P < 0.0001), and sudden cardiac death (adjusted HR 2.3; 95% CI 1.8-2.9, P < 0.0001). Cardiovascular hospitalization was also associated with an increased risk of post-discharge death (adjusted HR 2.8, 95% CI 2.5-3.2, P < 0.0001), vascular death (adjusted HR 2.8, 95% CI 2.4-3.2, P < 0.0001), and sudden cardiac death (adjusted HR 2.1, 95% CI 1.6-2.7, P < 0.0001) compared with patients not hospitalized for any cardiovascular reason. Conclusion Hospitalizations are associated an increased risk of with death and cardiovascular death in patients with atrial fibrillation.