Ghadah Almuaither

Background/Objectives: Apixaban is favored over warfarin for atrial fibrillation (Afib) and venous thromboembolism (VTE) due to its effectiveness, safety, and lack of routine monitoring. However, managing anticoagulation in hospitalized patients with acute kidney injury (AKI) is challenging due to altered pharmacokinetics and limited safety data. This study assesses the safety and efficacy of apixaban versus warfarin in these patients. Methods: This retrospective chart review at King Abdulaziz Medical City in Riyadh included adult patients (≥18 years) with AKI, as defined by the Kidney Disease Improving Global Outcome (KDIGO) guideline. Primary outcomes were rates of major and minor bleeding within 30 days, as defined by the International Society on Thrombosis and Haemostasis (ISTH), and thrombotic events. Secondary outcomes included 30-day rates of all-cause mortality and hospital readmissions. Results: Among 513 patients, 294 received apixaban and 219 received warfarin. Major bleeding within 30 days was significantly lower in the apixaban group (3.4%) compared to warfarin (7.3%) (p = 0.0461). Minor bleeding rates were similar (6.5% apixaban vs. 5.5% warfarin; p = 0.616). Thrombotic events occurred in 6.8% of patients, with no significant difference between apixaban (6.5%) and warfarin (7.3%) (p = 0.739). Mortality rates were 8.0%, with no significant difference (8.8% apixaban vs. 6.8% warfarin; p = 0.3846). Readmission rates were comparable (38.8% for apixaban vs. 39.7% for warfarin; p = 0.9499). Conclusions: In hospitalized AKI patients, apixaban was associated with a lower major bleeding risk compared to warfarin, with similar rates of thrombotic events, mortality, and readmissions, suggesting apixaban may be a safer option, warranting further research.