MO738CLINICAL IMPACT OF ORAL ANTICOAGULATION THERAPY ON MORTALITY, EMBOLIC AND HEMORRHAGIC EVENTS IN CHRONIC HEMODIALYSIS PATIENTS WITH ATRIAL FIBRILLATION

Abstract

Abstract Background and Aims A balance between embolic and bleeding risk is challenging in patients on chronic hemodialysis (HD). Embolic prevention with oral anticoagulation is the cornerstone for managing patients with atrial fibrillation (AF). However, there is a lack of specific recommendations for the use of antithrombotic therapy in HD patients with AF, and data about the efficacy and safety of oral anticoagulation in those patients are limited. Anticoagulation may exacerbate the hemorrhagic tendency; therefore, its potential benefits must be carefully weighed against hemorrhagic complications. We aimed to analyze the impact of oral anticoagulation on mortality, embolic and hemorrhagic events in chronic hemodialysis patients with AF. Method We used data from 106 hemodialysis patients [median age of 72 years (IQR 59–79) and 74.8% of the male gender] diagnosed with AF between 2016 and 2019. An analysis was performed to match the baseline characteristics of patients treated or not with oral vitamin K antagonists (OAK). The impact of oral anticoagulation in the embolic and hemorrhagic risk was assessed by a competitive risk analysis, with death being the competitive event. For embolic risk, we have considered a stroke, pulmonary or peripheral embolism, including arteriovenous fistula thrombosis. For bleeding risk, we have considered major bleeding according to the ISTH definition. Results More than half of HD patients with AF were anticoagulated (65.1%; n=69). During a median follow-up of 27.6 months (IQR 11.8-42.9 months), 33 patients died (31.1%), 21 presented embolic events (19.8%), and 19 had a major bleeding event (17.9%). In total, we recorded eight cerebral bleedings, ten gastrointestinal bleedings, and one urogenital bleeding. Of those, eleven (57.9%) were observed in orally anticoagulated patients (p=0.066). Patients with bleeding events had a higher prevalence of arterial hypertension (p=0.012), diabetes mellitus (p=0.002), advanced age (p=0.03) lower platelets count (p<0.001) and lower hemoglobin (p=0.04). After propensity-score matching, anticoagulation therapy was associated with lower mortality rate (HR 0.86, 95% CI 0.71-0.92; p=0.004) and embolic events (HR 0.78, 95% CI 0.69-0.88; p=0.003), but more bleeding events (HR 1.83, 95% CI 1.34-2.91; p=0.002). Conclusion Among HD patients with AF, oral anticoagulation was associated with lower all-cause mortality. Although survival free of embolic events was significantly higher in patients with anticoagulation, the risk of major bleeding was almost twice than in non-anticoagulated patients. Patients who experienced bleeding events did not show worse outcomes. This study strengthens the role of low hemoglobin and platelet counts as well as comorbidities on increased bleeding risk.