Influence of Body Mass Index on the Prognostic Value of N-Terminal Pro-B-Type Natriuretic Peptide Level in Chinese Patients with Heart Failure.

N-terminal pro-B-type natriuretic peptide (NT-proBNP) is an essential biomarker for the prediction of heart failure (HF), but its prognostic ability across body mass index (BMI) categories needs to be clarified. Our study aimed to explore the association between BMI and NT-proBNP and assess the effect of BMI on the prognostic ability of NT-proBNP in Chinese patients with HF. We retrospectively analyzed clinical data from the FuWai Hospital HF Center in Beijing, China. According to the Chinese adult BMI standard, 1,508 patients with HF were classified into four groups: underweight (BMI < 18.5 kg/m), normal weight (BMI 18.5-23.9 kg/m, as a reference category), overweight (BMI 24-27.9 kg/m), and obesity (BMI ≥ 28 kg/m). NT-proBNP was examined for its prognostic role in adverse events as an endpoint. BMI was independently and negatively associated with NT-proBNP (β = -0.074; P < 0.001), and NT-proBNP levels tended to decrease as BMI increased across the different BMI categories. The results of our study differ from those of other studies of European-American populations. In this study, NT-proBNP was a weak predictor of a 4-year adverse prognosis in underweight patients (BMI < 18.5 kg/m). In other BMI categories, NT-proBNP was an independent predictor of adverse events in HF. BMI and sex significantly affected the optimal threshold for NT-proBNP to predict the risk of adverse events. There is a negative correlation between BMI and NT-proBNP, and NT-proBNP independently predicts adverse HF events in patients with a BMI of ≥ 18.5 kg/m. The optimal risk prediction cutoffs are lower in patients who are overweight and obese.