#3896 SAFETY OUTCOMES OF ORAL ANTICOAGULANT THERAPY IN PATIENTS WITH ATRIAL FIBRILLATION AND CHRONIC KIDNEY DISEASE
Authors: Igamberdieva Ranokhon , Abdullaev Sherzod 
Published: June 2023

Abstract

Background and Aims
The comorbid conditions of atrial fibrillation (AF) and chronic kidney disease (CKD) leads to an increased risk of thromboembolic complications, but on the other hand is a risk factor for various bleeding. Oral anticoagulant therapy is the standard for the prevention of thromboembolic complications in AF. But with the deterioration of kidney function, the risk of hemorrhagic complications increases dramatically. This problem makes it difficult to choose an effective and safe oral anticoagulant therapy. Clinical data on the use of new oral anticoagulants (NOACs) in patients with AF and advanced CKD are limited, which determines the relevance of conducting studies in comparison with vitamin K antagonists. The aim of study was evaluation of safety parameters for the using of rivaroxaban in patients with stage 4 CKD with AF.

Method
The study included 109 patients over the age of 18 with a diagnosis of stage 4 CKD (eGFR – 15–29 ml/min/1.72 m2) and non-valvular AF. They were randomized in a 2:1 ratio to either rivaroxaban 15 mg (n = 73) or warfarin (n = 36). The mean follow-up period was 18 months. In the warfarin group, time in therapeutic range (TTR) &gt;70% was achieved in 34 (94%) patients. Exclusion criteria were a history of bleeding that required hospitalization; decrease in hemoglobin level below 80 g/l, platelet count below 100 × 109/l; indications for taking antiplatelet therapy; chronic use of drugs that increase the risk of bleeding. The analysis of the observed hemorrhagic events was carried out using the BARC and ISTH scales. Classification of anemia was carried out according to the recommendations of the World Health Organization.

Results
Patients taking warfarin were significantly more likely to develop minor bleeding according to the BARC scales and ISTH and all clinically significant bleeding on the ISTH scale. In patients with AF and CKD receiving warfarin therapy, minor bleeding (MB) according to the BARC scale was observed in 72.2% (n = 26), minor clinically significant bleeding (MCSB) in 8.33% (n = 3), major bleeding in 8.33% (n = 3) of cases; and in the group of patients treated with rivaroxaban, MB was observed in 42.4% (n = 31, p&lt;0.01), MCSB in 2.74% (n = 2, p = 0.32), major bleeding in 2.74% (n = 2, p = 0.32) of cases. When assessing bleeding on the ISTH scale during therapy with VKA, MB – 61.1% (n = 22), MCSB – 19.4% (n = 7), major bleeding – 8.33% (n = 3); against the background of NOACs therapy, MB – 36.9% (n = 27, p = 0.01), MCSB in 8.2% (n = 6, p = 0.06), major bleeding in 2.74% (n = 2, p = 0.32). All clinically significant hemorrhagic events according to the BARC scale in the warfarin group occurred more than 16.6% (n = 6) compared with the rivaroxaban group 5.4% (n = 4, p = 0.06); when analyzed according to the ISTH scale, the number of patients receiving VKA anticoagulant therapy 27.7% (n = 10) significantly prevailed over patients on the background of NOACs 10.9% (n = 8, p = 0.03). Analysis of hemoglobin level did not reveal significant dynamics and significant differences between the groups: the median hemoglobin level at inclusion was 129 g/l in the rivaroxaban group and 123 g/l in the warfarin group (p = 0.3), after 18 months - 130 g/l and 121 g/l, respectively (p = 0.7).

Conclusion
Data suggesting a favorable safety profile for NOACs (rivaroxaban) compared with VKAs (warfarin) in patients with AF and advanced CKD was obtained in this study. Taking rivaroxaban was accompanied by a significantly lower number of hemorrhagic events, which may indicate a safe effect of the drug. No significant changes in hemoglobin levels were found in both groups. Confirmation of these data may be key in choosing an anticoagulant in patients with AF and advanced CKD.