Clinical characteristics and outcomes of patients hospitalized with heart failure with preserved ejection fraction and low NT-proBNP levels

The aim of this study was to investigate the clinical characteristics and prognosis of patients hospitalized with heart failure with preserved ejection fraction (HFpEF) and low N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels. Seven hundred ninety consecutive patients hospitalized with HFpEF from 2006 to 2017 were enrolled. Clinical characteristics and outcomes were compared between low NT-proBNP group (<300 ng/L) and elevated NT-proBNP group (≥300 ng/L). 108 HFpEF patients (13.7%) presented with low NT-proBNP levels. Age, body mass index, atrial fibrillation, New York Heart Association functional class, and albumin were independent predictors of low NT-proBNP levels in HFpEF patients. During the median follow-up duration of 1103 days, 11 patients (10.2%) in low NT-proBNP group suffered from primary endpoint event. Elevated NT-proBNP group had a higher risk of all-cause death or heart transplantation than low NT-proBNP group (adjusted HR [95%CI]: 2.36 [1.24,4.49], P = .009). Stratified analyses showed that the association between NT-proBNP (elevated NT-proBNP group vs low NT-proBNP group) and risk of all-cause death or heart transplantation was stronger in non-atrial fibrillation patients than in atrial fibrillation patients (P value for interaction = .025). Furthermore, the associations between NT-proBNP and risk of all-cause death or heart transplantation were stronger in younger and male patients than in older and female patients. However, both subgroups only reached borderline significant (P values for interaction = .062 and .084, respectively). Our findings suggest that low NT-proBNP levels were common in patients hospitalized with HFpEF. Patients with HFpEF and low NT-proBNP levels had a better prognosis than those with elevated NT-proBNP levels, particularly in younger, male, and non-atrial fibrillation patients.