Clinical benefits and risks of anticoagulation therapy according to the degree of chronic kidney disease in patients with atrial fibrillation

Background The clinical benefits and risks of anticoagulation therapy in patients with chronic kidney disease (CKD) are still inconclusive. We describe the outcomes of patients with atrial fibrillation (AF) after anticoagulation therapy according to differences in creatinine clearance (CrCl). We also aimed to determine the patients who could benefit from anticoagulation therapy. Methods This is a retrospective observational review of patients with AF who were managed at Asan Medical Center (Seoul, Korea) between January 1, 2006, and December 31, 2018. Patients were categorized into groups according to their baseline CrCl by Cockcroft–Gault equation and their outcomes were evaluated (CKD 1, ≥ 90 mL/min; CKD2, 60–89 mL/min; CKD3, 30–59 mL/min; CKD4, 15–29 mL/min; CKD 5, < 15 mL/min). The primary outcome was NACE (net adverse clinical events), defined as a composite of all-cause mortality, thromboembolic events, and major bleeding. Results We identified 12,714 consecutive patients with AF (mean 64.6 ± 11.9 years, 65.3% male, mean CHA 2 DS 2 -VASc score 2.4 ± 1.6 points) between 2006 and 2017. In patients receiving anticoagulation therapy (n = 4447, 35.0%), warfarin (N = 3768, 84.7%) was used more frequently than NOACs (N = 673, 15.3%). There was a higher 3-year rate of NACE with renal function deterioration (14.8%, 18.6%, 30.3%, 44.0%, and 48.8% for CKD stages 1–5, respectively).The clinical benefit of anticoagulation therapy was most prominent in patients with CKD 1 (hazard ratio [HR] 0.49, 95% confidence interval [CI] 0.37–0.67), 2 (HR 0.64 CI 0.54–0.76), and 3 (HR 0.64 CI 0.54–0.76), but not in CKD 4 (HR 0.86, CI 0.57–1.28) and 5 (HR 0.81, CI 0.47–1.40). Among patients with CKD, the benefit of anticoagulation therapy was only evident in those with a high risk of embolism (CHA 2 DS 2 -VASc score ≥ 4, HR 0.25, CI 0.08–0.80). Conclusion Advanced CKD is associated with a higher risk of NACE. The clinical benefit of anticoagulation therapy was reduced with the increasing CKD stage.