Background: The ELDERCARE-AF trial showed that low-dose edoxaban benefits elderly patients with nonvalvular atrial fibrillation considered ineligible for standard oral anticoagulants due to high bleeding risk, but whether this applied to patients with extremely low body weight was unclear.
Methods and results: This was a prespecified subanalysis by body weight (≤45, >45 kg) of the phase 3, multicenter, randomized, double-blind, placebo-controlled, event-driven ELDERCARE-AF trial, which compared low-dose edoxaban (15 mg once daily) with placebo in Japanese patients considered ineligible for oral anticoagulants at the recommended therapeutic strength or the approved doses. The primary efficacy and safety end points were stroke or systemic embolism and major bleeding (International Society on Thrombosis and Hemostasis definition), respectively. The ≤45-kg weight group included 374/984 patients (38.0%), and the >45-kg group included 610/984 patients (62.0%). The stroke or systemic embolism rate was lower with edoxaban than placebo in both weight groups (≤45 kg: hazard ratio [HR], 0.36 [95% CI, 0.16-0.80]; >45 kg: HR, 0.31 [95% CI, 0.13-0.73]; interaction P=0.82). Major bleeding incidence was numerically higher with edoxaban than placebo (≤45 kg: HR, 3.05 [95% CI, 0.84-11.11]; >45 kg: HR, 1.40 [95% CI, 0.56-3.48), with no interaction with body weight (interaction P=0.33). All-cause mortality was higher in the ≤45-kg group, with no significant difference between treatment groups.
Conclusions: The benefit of edoxaban 15 mg was consistent in elderly patients with atrial fibrillation and extremely low body weight, though clinicians must remain vigilant about the risk of major bleeding, especially gastrointestinal bleeding.
Registration information: ClinicalTrials.gov. Identifier: NCT02801669.
Keywords: atrial fibrillation; bleeding; body weight; low‐dose edoxaban.