Rivaroxaban vs Warfarin for Atrial Fibrillation in CKD Population
Rivaroxaban, a direct oral anticoagulant (DOAC), is associated with better efficacy and similar safety compared with warfarin in patients with nondialysis-dependent chronic kidney disease (CKD).
Min Jun, PhD, MScMed, of The George Institute for Global Health in Sydney, Australia and colleagues conducted a retrospective study of 55,568 adults with atrial fibrillation from Australia and Canada, including 27,784 rivaroxaban users propensity-score matched to 27,784 warfarin users. The mean age of the matched cohort was 74 years. Of the cohort, 33.5% had an estimated glomerular filtration (eGFR; in mL/min/1.73m2) less than 60, including 2.4% overall with an eGFR less than 30 (most with eGFR 15-29).
Compared with warfarin use, rivaroxaban use was associated with a 28%, 22%, 30%, and 22% decreased risk of the composite endpoint of death, stroke, and transient ischemic attack within 1 year among patients with an eGFR of 60 or more, 45-59, 30-44, and less than 30, respectively. All results were significant except for the eGFR 45-59 group.
The risk for major bleeding requiring hospitalization did not differ between rivaroxaban and warfarin users across eGFR categories less than 60. Patients with an eGFR of 60 or more who used rivaroxaban, however, had a significant 25% decreased risk for major bleeding.
Still, the investigators urged caution.
“There remains insufficient evidence to establish benefits or harms of DOACs or warfarin in patients with advanced CKD, who have been largely excluded from randomized trials.”
In an accompanying editorial, Marisa Battistella, HBSc, BScPhm, Pharm D, of the University Health Network in Toronto, Ontario, Canada, and colleagues pointed out that only 2.4% of the cohort had an eGFR less than 30, which may indicate a prescribing bias against DOACs in this patient group. DOACs, such as rivaroxaban, are partially renally cleared and may accumulate, they reiterated. Dr Battistella and collaborators pointed out that guidelines differ markedly in their guidance for patients with an eGFR less than 30, especially those on dialysis. Dosing remains a crucial decision for both efficacy and safety. Adding to the known bleeding risk associated with CKD remains a major concern.
“Considering the existing evidence on anticoagulant use in those with advanced CKD, it is clear that 1 agent is not the magic potion above all others,” the editorialists’ wrote. “Still, Ha et al were able to add to a limited body of real-world evidence showing effectiveness and safety of rivaroxaban in those with eGFR <30 mL/min/1.73m2. More robust studies are needed to demystify the role of DOACs across the spectrum of kidney function.”
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Ha JT, Scaria A, Andrade J, et al. Safety and effectivenss of rivaroxaban versus warfarin across GFR levels in atrial fibrillation: a population-based study in Australia and Canada. Kidney Med. 16;5(7):100675. doi:10.1016/j.xkme.2023.10067
Mohsen M, Zhang T, Battistella M. Anticoagulation in CKD: trials and tribulations. Kidney Med. 16;5(7). Published June 8, 2023. doi:10.1016/j.xkme.2023.100686References