Cost-Utility Analysis of Apixaban versus Warfarin in Atrial Fibrillation Patients with Chronic Kidney Disease

Abstract Background Warfarin use for stroke prevention in atrial fibrillation (AF) patients with chronic kidney disease is debated. Apixaban was shown to be safer than warfarin, with superior reduction in the risk of stroke, systemic embolism, mortality, and major bleeding irrespective of kidney function. Objectives To evaluate the cost-utility of apixaban compared with warfarin in AF patients at different levels of kidney function. Methods A Markov model was used to estimate the cost effectiveness of apixaban compared with warfarin in AF patients at three levels of kidney function: estimated glomerular filtration rate (eGFR) of more than 80 ml/min, 50 to 80 ml/min, and 50 ml/min or less. Event rates and associated utilities were obtained from previous literature. The model adopted the US health care system perspective, with hospitalization costs extracted from the Healthcare and Utilization Project. Treatment costs were obtained from official price lists. Univariate and probabilistic sensitivity analyses were performed to evaluate the robustness of results. Results Apixaban was a dominant treatment strategy compared with warfarin in AF patients with eGFR levels of 50 ml/min or less and 50 to 80 ml/min. In patients with an eGFR of more than 80 ml/min, apixaban was cost-effective compared with warfarin, costing $6307 per quality-adjusted life-year gained. Results were consistent assuming anticoagulant discontinuation after major bleeding events. Compared with dabigatran and rivaroxaban, apixaban was the only cost-effective anticoagulant strategy relative to warfarin in both mild and moderate renal impairment settings. Conclusions Apixaban is a favorably cost-effective alternative to warfarin in AF patients with normal kidney function and potentially cost-saving in those with renal impairment.