The Influence of Renal Function on Safety and Effectiveness of Oral Anticoagulant Treatment among Frail Elderly Patients with Non-Valvular Atrial Fibrillation and Chronic Kidney Disease

INTRODUCTION: The effectiveness and safety of oral anticoagulants (OACs) in patients with chronic kidney disease (CKD) and non-valvular atrial fibrillation (NVAF) in frail elderly patients have not been fully established. We aimed to evaluate the safety and effectiveness of OACs in frail elderly patients with atrial fibrillation (AF) and stage II-III CKD. METHODS: Frail elderly patients ≥65 years with AF and CKD who received OAC from January 2022 to June 2024 were retrospectively identified. Primary endpoints were composite of ischemic stroke and systemic embolism (IS/SE), and composite of intracranial hemorrhage (ICH) and/or gastrointestinal (GI) bleeding. Secondary endpoints included any bleeding. RESULTS: -VASc score was nonsignificant (2.6 ± 1.01 vs. 2.8 ± 0.89, p value 0.054), for GFR ≥60 and GFR <60 mL/min/1.73 m2 patients, respectively. HAS-BLED score (1.9 ± 0.67 vs. 2.3 ± 0.70, p value 0.071) for GFR ≥60 and GFR <60 mL/min/1.73 m2 patients respectively. While the observed incidence of ICH/GI bleeding was numerically higher in patients with GFR <60 mL/min/1.73 m2, Cox proportional hazards regression did not demonstrate a statistically significant difference in hazard between the groups. The incidence of composite IS/SE was 8.5% in GFR ≥60 mL/min/1.73 m2 versus 8.7% in GFR <60 mL/min/1.73 m2 (HR 1.02, 95% CI: 0.60-1.74, p = 0.24). Composite ICH/GI bleeding occurred in 7.1% versus 9.3% (HR 2.15, 95% CI: 0.91-4.56, p = 0.41). CONCLUSION: In this study comparing frail elderly patients with NVAF and CKD stage II versus stage III receiving OACs, we observed no significant difference in the risk of IS/SE or ICH/GI bleeding between groups. These findings suggest that within moderate CKD (eGFR 30-89 mL/min), renal function stage may not independently influence OAC-related outcomes when anticoagulation is well managed. Our results may not generalize to less frail populations or those with advanced CKD. Further prospective studies with larger sample size are needed to provide clearer guidance on the optimal use of OACs in this challenging clinical scenario.