Real-World Clinical Outcomes of Warfarin Use Among Patients with Chronic Kidney Disease in Thailand

Abstract

Background: Warfarin has been extensively used for a long time under various conditions. However, comprehensive evidence is scarce regarding the effectiveness and safety of warfarin in each group of chronic kidney disease (CKD) among Thai patients. Objective: The present study used real-world data from Thailand to determine the incidence of thromboembolism and bleeding among patients with CKD with different estimated glomerular filtration rates (eGFRs). Materials and Methods: A retrospective cohort study was conducted among Thai patients with CKD who used warfarin at three tertiary-care hospitals between January 2015 and December 2019. Patients were included and divided into five groups according to their eGFRs as N1 to N5 with eGFR greater than 60, 30 to 59, 15 to 29, less than 15 and not receiving dialysis, and less than 15 mL/minute/1.73 m² with dialysis, respectively. The incidence density was analyzed to report thromboembolism and bleeding outcomes. Results: During the follow-up period, 2.28 per 100 person-years of patients developed thromboembolism with N1 to N5 at 2.00, 2.27, 3.68, 4.66, and 1.70 per 100 person-years, respectively. Furthermore, 2.33 per 100 person-years of patients developed major bleeding with N1 to N5 at 1.17, 2.25, 4.03, 11.37, and 5.12 per 100 person-years, respectively. Conclusion: The present study found that the incidence of thromboembolism and major bleeding among patients with CKD increased across different eGFR groups who used warfarin. Interestingly, patients with CKD in the N4 group had a higher incidence of thromboembolism and major bleeding than the other groups. Thus, close monitoring and frequent follow-up are recommended for this group. Keywords: Vitamin K antagonist; Bleeding; Thromboembolism; Chronic kidney disease