Dabigatran and Rivaroxaban Use in Atrial Fibrillation Patients on Hemodialysis

D abigatran is a novel, orally available, direct thrombin inhibitor that is currently approved to prevent stroke in patients with atrial fibrillation. The anticoagulant is easier to use than warfarin because laboratory monitoring is not required and there are fewer drug–drug interactions. 1 Accordingly, dabigatran use in the United States increased from 3.1% of all oral anticoagulation visits in 2010 to 18.9% in 2011. 2 By virtue of the growing availability of dabigatran, the drug is sometimes prescribed for other situations where the drug has not been rigorously studied. For example, in 2011, Kirkly et al 2 reported that 37% of treatment visits for dabigatran were for coronary heart disease, hypertensive heart disease, and venous thromboembolism. Similar trends will likely be seen with rivaroxaban, another novel anticoagu-lant that is directed against Factor Xa, which became available in 2011. Prescription of these novel oral anticoagulant drugs (NOAC) in dialysis patients is currently contraindicated because the drugs are cleared via the kidneys and drugs levels can bioaccumulate to precipitate bleeding. 6,7 Dabigatran is cleared by dialysis, which leads to a precipitous drop in the drug level, whereas rivaroxaban is not cleared by dial-ysis because 95% of rivaroxaban is protein bound. Background—Dabigatran and rivaroxaban are new oral anticoagulants that are eliminated through the kidneys. Their use in dialysis patients is discouraged because these drugs can bioaccumulate to precipitate inadvertent bleeding. We wanted to determine whether prescription of dabigatran or rivaroxaban was occurring in the dialysis population and whether these practices were safe. Methods and Results—Prevalence plots were used to describe the point prevalence (monthly) of dabigatran and rivaroxaban use among 29 977 hemodialysis patients with atrial fibrillation. Poisson regression compared the rate of bleeding, stroke, and arterial embolism in patients who started dabigatran, rivaroxaban, or warfarin. The first record of dabigatran prescription among hemodialysis patients occurred 45 days after the drug became available in the United States. Since then, dabigatran and rivaroxaban use in the atrial fibrillation–end-stage renal disease population has steadily risen where 5.9% of anticoagulated dialysis patients are started on dabigatrian or rivaroxaban. associated with a higher risk of hospitalization or death from bleeding when compared with warfarin. The risk of hemorrhagic death was even larger with dabigatran relative to warfarin. There were too few events in the study to detect meaningful differences in stroke and arterial embolism between the drug groups. Conclusions—More dialysis patients are being started on dabigatran and …