What are the special considerations for the management of atrial fibrillation in CKD patients?
Oral anticoagulation can be considered for the prevention of cardioembolic strokes from atrial fibrillation.
This is supported by subgroup analyses from one single, randomized, controlled trial (Stroke Prevention in Atrial Fibrillation SPAF-3 trial), which found that warfarin reduced the risk of strokes in patients with CKD stages 3A to 3B.
However, strong evidence is lacking in the advanced stages of CKD. There are no randomized trials assessing the benefits and risks of anticoagulation in patients with advanced stages of CKD or on dialysis, and the observational studies published so far have been split.
Moreover, platelet dysfunction, anemia, endothelial, and vascular dysfunction, as well as other factors make the risk of intracranial hemorrhage or gastrointestinal bleeding significantly higher in people with advanced kidney disease.
As such, the risk-benefit balance of anticoagulation in advanced CKD may be tilted by increased bleeding complications.
Overall, in patients with CKD and not on dialysis, the risk of thromboembolism should be assessed using the CHA2DS2-VASc score.
This scoring system accounts for congestive heart failure, hypertension, age ≥75 (doubled), diabetes, stroke or transient ischemic attack, or systemic embolism (doubled), vascular disease, age 65 to 74, and sex. Men with a CHA2DS2-VASc score ≥1 and women with a score ≥2 should be considered for anticoagulation. For patients on dialysis, the initiation of anticoagulation needs to be individualized.
Careful monitoring of the degree of anticoagulation is necessary in these patients, and the risk of bleeding is further increased when oral anticoagulation is combined with aspirin therapy.
The HAS-BLED (hypertension, abnormal kidney/liver function [1 point each], stroke, bleeding history or predisposition, labile INR, elderly [>65 years], drugs/alcohol concomitantly [1 point each]) is used in atrial fibrillation patients to determine those at a higher risk of bleeding.
However, while it accounts for abnormal kidney function, its use has not been formally validated in patients with advanced CKD and dialysis.