Survival benefit of anticoagulation in patients with end-stage kidney disease and atrial fibrillation: A national population-based study

BackgroundThe prevalence of atrial fibrillation (AF) in patients with end-stage kidney disease (ESKD) is high and increasing; however, current evidence is insufficient and conflicting regarding oral anticoagulant (OAC) use in patients with ESKD and AF. MethodsA retrospective cohort study of patients diagnosed with AF after ESKD from January 2007 to December 2017 was conducted using the Korea National Health Insurance System Database. The primary outcome was all-cause death. Secondary outcomes were ischemic stroke, severe bleeding, and major adverse cardiovascular event (MACE). Outcomes were compared between OAC user and nonuser groups using landmark analysis (6 months after AF diagnosis) and 1:3 propensity score matching. ResultsAmong patients diagnosed with AF after ESKD, the number of patients prescribed any OAC increased 2.3-fold from 2012 (n=3,579) to 2018 (n=8,341), and the proportion prescribed direct OACs (among those prescribed any OAC) increased steadily from 0% in 2012 to 51.4% in 2018. Matched cohort analysis showed that compared with OAC nonusers, OAC users had a lower risk of all-cause death (hazard ratio [HR] 0.71; 95% confidence interval [CI] 0.58-86), ischemic stroke (HR 0.63; 95% CI 0.43-92), and MACE (HR 0.76; 95% CI 0.59-0.98) but no increased risk of severe bleeding (HR 1.58; 95% CI 0.99-2.52). Subgroup analysis according to type of OAC revealed that patients receiving direct OACs had a significantly lower risk of all-cause death (HR 0.44; 95% CI 0.28-0.69), ischemic stroke (HR 0.36; 95% CI 0.13-0.99), and MACE (HR 0.42; 95% CI 0.22-0.79) than OAC nonusers but no increased risk of severe bleeding (HR 0.26; 95% CI 0.04-1.90). Conversely, warfarin use was not associated with all-cause death (HR 0.98; 95% CI 0.79-1.21), ischemic stroke (HR 0.78; 95% CI 0.51-1.19), or MACE (HR 1.03; 95% CI 0.79-1.36) but was associated with a higher risk of severe bleeding (HR 2.43; 95% CI 1.50-3.93). ConclusionsIn patients with ESKD and AF, OACs were associated with reduced all-cause death, ischemic stroke, and MACE risks but no increased risk of severe bleeding. Direct OACs were preferable to warfarin with regard to efficacy and safety. Clinical PerspectiveO_ST_ABSWhat is new?C_ST_ABSO_LIOutcomes of oral anticoagulation in patients with end-stage kidney disease and atrial fibrillation are currently unknown. C_LIO_LIIn this nationwide cohort study of patients with end-stage kidney disease and atrial fibrillation who had a CHA2DS2-VASc score of [≥] 1 (men) or [≥] 2 (women), oral anticoagulant therapy was associated with lower risks of all-cause death, stroke, and major adverse cardiovascular event but was no difference in severe bleeding, compared with no anticoagulation. C_LIO_LIWhen analyzing types of anticoagulants, these reduced risks were found in patients receiving direct oral anticoagulants but not warfarin. C_LI What are the clinical implications?O_LIAnticoagulation therapy may be superior to no anticoagulation in patients with end-stage kidney disease and atrial fibrillation. C_LIO_LIThese findings require confirmation in randomized trials. C_LI