Abstract 9071: Prognosis of Elderly Non-Valvular Atrial Fibrillation Patients Stratified by B-type Natriuretic Peptide Concentration: A Subanalysis of Data from the ELDERCARE-AF Trial

Introduction: B-type natriuretic peptide (BNP) is a known predictor of prognosis and disease severity in patients with heart failure. However, only limited data are available on the relation between BNP and outcomes in very elderly (age, ≥ 80 years) patients ineligible for standard anticoagulation with non-valvular atrial fibrillation (NVAF). Therefore we evaluated the prognostic and therapeutic outcomes of very elderly Japanese NVAF patients stratified by BNP concentration. Methods: This was a subanalysis of data from ELDERCARE-AF, a multicenter, randomized, double-blind, placebo-controlled phase 3 study of edoxaban 15 mg (once daily) in very elderly Japanese NVAF patients considered ineligible for standard anticoagulant treatment. Patients were stratified according to BNP concentration at enrollment, and their outcomes were compared. The primary efficacy endpoint was stroke or systemic embolism (SSE). The primary safety endpoint was major bleeding. Results: A total of 984 patients (mean age, 86.6 years) were randomized to edoxaban 15mg ( n = 492) or placebo ( n = 492). BNP concentration at enrollment was < 200 pg/mL (low), 200 to < 400 pg/mL (moderate), and ≥ 400 pg/mL (high) in 428, 300, and 256 patients, respectively. Mean CHADS 2 score was 2.9 in the low BNP and 3.2 in the moderate and high BNP groups. The incidences of SSE were 1.2%/patient-year (7/428), 5.9%/patient-year (24/300), and 8.6%/patient-year (28/256) in the low, moderate, and high BNP groups, respectively: unadjusted HR = 5.03 (95% confidential interval [CI], 2.17-11.67), P = 0.0002, for low versus moderate BNP; unadjusted HR = 7.07 (3.09-16.18), P < 0.0001, for low versus high BNP. No significant intergroup differences were found for the incidence of major bleeding. Edoxaban 15mg was superior to placebo in preventing SSE in the moderate and high BNP groups: unadjusted HR, 0.27 (0.10-0.73), P < 0.01, and unadjusted HR, 0.34 (0.15-0.81), P < 0.05, respectively. There was no significant difference in major bleeding between the edoxaban 15mg and placebo groups. Conclusions: In very elderly NVAF patients, BNP concentration was positively related to the incidence of SSE, and edoxaban 15mg had a preventive effect, regardless of BNP concentration.