Anticoagulation Therapy in Advanced Chronic Kidney Disease: Balancing Bleeding and Thromboembolic Risk.

Advanced chronic kidney disease (CKD) presents a complex hemostatic paradox, characterized by a simultaneous increase in bleeding and thromboembolic risks. This study aimed to evaluate and compare the safety and efficacy of apixaban versus acenocoumarol in a real-world cohort of patients across advanced CKD stages (pre-dialysis and hemodialysis). We conducted a retrospective observational study including 84 adults with CKD stages 4 and 5 (40.5% in stage 4; 59.5% in stage 5, of whom 86.0% were on chronic hemodialysis) receiving oral anticoagulation for at least 3 months. Patients were stratified by CKD stage and anticoagulant type (apixaban vs. acenocoumarol). Clinical outcomes included major and clinically relevant bleeding, anticoagulant overdose, and thromboembolic events. Bleeding events were more frequent in CKD stage 5 than in stage 4 (66.0% vs. 44.1%, p = 0.06), highlighting a pronounced hemorrhagic burden that increases with disease progression. Apixaban was associated with significantly fewer total bleeding events (44.4% vs. 66.7%, p = 0.04) and a lower rate of anticoagulant overdoses (5.6% vs. 18.8%, p = 0.04) compared with acenocoumarol. Thromboembolic event rates did not differ significantly between the two anticoagulant groups (13.9% vs. 16.7%, p = 0.72). Conventional risk scores (CHA2DS2-VASc and HAS-BLED) showed limited discriminatory capacity for actual clinical events in this advanced CKD population. In patients with advanced CKD, oral anticoagulation is associated with a high hemorrhagic burden that intensifies as renal function declines. Apixaban demonstrated a more favorable safety profile than acenocoumarol without a loss of thromboembolic protection. These findings suggest that stage-specific biological factors, rather than conventional risk models alone, should guide anticoagulation strategies in this population.