Prognosis of elderly non-valvular atrial fibrillation patients stratified by B-type natriuretic peptide: ELDERCARE-AF subanalysis

Abstract

B-type natriuretic peptide (BNP) is a risk factor for stroke and cardiac death in patients with atrial fibrillation. We hypothesized the prognostic outcomes of very elderly non-valvular atrial fibrillation patients ineligible for standard anticoagulation treatment would vary according to BNP stratification. In this subanalysis of the ELDERCARE-AF trial, patients were stratified by BNP levels at enrollment, and clinical outcomes compared among BNP subgroups. Hazard ratios were adjusted for age, atrial fibrillation type, body mass index, creatine clearance, congestive heart failure, and D-dimer. BNP levels were measured using chemiluminescence enzyme immunoassays. In total, 984 patients (average age: 86.6 years) not considered eligible for oral anticoagulant therapy at approved doses for stroke prevention were included. The BNP levels at enrollment were <200 (low), 200 to <400 (moderate), and ≥400 (high) pg/mL in 428, 300, and 256 patients, respectively. The number (%) of patients with stroke or systemic embolism (SSE) was 7 (1.2%), 24 (5.9%), and 28 (8.6%) in the low, moderate, and high BNP subgroups, respectively (adjusted hazard ratio 3.82, P=.0025 for low vs moderate BNP and 4.76, P=.0007 for low vs high BNP). There was no significant difference in major bleeding incidence between the BNP subgroups. Edoxaban 15 mg was associated with a consistent reduction in SSE vs placebo in all BNP subgroups. Stratification by BNP level was associated with the incidence of SSE for very elderly non-valvular atrial fibrillation patients ineligible for standard anticoagulation treatment, and the effect of edoxaban 15 mg was consistent across BNP levels.