The clinical bleeding risk scores (eg, HAS-BLED, ORBIT, RIA) all include CKD measures as part of their score calculation.103 Therefore, CKD is both a marker of risk of disease and of its therapy, and there is signi cant controversy as to the net clinical bene t of oral anticoagulation in severe CKD despite encouraging observational studies.432 Fourth, there are virtually no randomized trial data of oral anticoagulation in severe CKD (creatinine clearance [CrCl] < 25-30 mL/min). Some observational data suggest that warfarin may be harmful in end-stage renal disease patients on hemodialysis, with no reduction (or an increase) in stroke and an excess of major bleeding; however, many of these studies (largely from North America) do not report quality of anticoagulation control, as re ected by TTR.433-435 In contrast, European data suggest that there is a bene cial reduction in ischemic stroke which outweighs the increase in severe bleeding, where TTR is good (> 65%-70%).433-435 The latest systematic review and meta-analysis by Harel of 14 observational studies (20,398 participants) among hemodialysis with AF, found that the use of warfarin was not associated with ischemic stroke (14 or ICH (hemorrhagic stroke; 4 studies; 15,726 participants; concluded that warfarin was not associated with a clear bene t or harm among patients who have AF and receive dialysis. However, there was marked study heterogeneity including the inability to account for major confounders such as the quality of anticoagulation control (TTR). 