Oral anticoagulation for stroke prevention in atrial fibrillation and advanced kidney disease

Background Net benefit of oral anticoagulation (OAC) with vitamin K-antagonists (VKA) or direct-acting oral anticoagulants (DOAC) in patients with advanced chronic kidney disease and atrial fibrillation remains uncertain. Objectives We examined the use, efficacy, and safety of OAC in patients with estimated glomerular filtration rate (eGFR) <30 ml/min/1.73 m2 (including dialysis treated patients) and atrial fibrillation. Methods In a retrospective cohort study, patients diagnosed with atrial fibrillation and eGFR<30 ml/min/1.73 m2 were identified in national Danish registers between 2010 and 2022. Initiation of OAC was identified based on redemption of a relevant prescription. One-year risks of thromboembolic event, major bleeding, and death associated with OAC and no treatment were computed, standardized to the distribution of risk factors in the sample based on hazards determined in multiple Cox regression models adjusted for age and sex. Results A total of 3208 patients were included (mean age 80 years, 52.8% males, 20.9% chronic dialysis). OAC was initiated in 1375 (42.9%) patients, hereof 48.1% VKA and 51.9% DOAC. One-year risks in non-treated and anticoagulated patients were 4.8% (95% CI 3.8%-5.7%) and 3.6% (95% CI 2.8%-4.6%), p=0.028, for thromboembolic event; 7.6% (95% CI 6.6%-8.7%) and 10.5% (95% CI 9.3%-12.1%), p<0.001, for major bleeding; and 36.3% (95% CI 34.2%-38.3%) and 29.6% (95% CI 27.6%-31.6%), p<0.001, for death, respectively. Conclusions In a retrospective study on patients with advanced chronic kidney disease and atrial fibrillation, OAC was associated with overall decreased one-year risk of thromboembolic event and death offset by increased one-year risk of major bleeding.