The Impact of Body Mass Index on the Prognostic Value of N-Terminal proB-Type Natriuretic Peptide in Patients with Heart Failure: an Analysis from the Korean Heart Failure (KorHF) Registry.

Background and objectives: Although an inverse correlation between the level of amino (N)-terminal pro-brain natriuretic peptide (NT-proBNP) and body mass index (BMI) has been reported, the impact of BMI on the prognostic value of NT-proBNP has not been well addressed.

Methods: A total of 1,877 patients (67-year-old and 49.9% females) hospitalized for acute heart failure (HF) with documented NT-proBNP levels at baseline were included. Patients were classified into 2 groups by BMI (nonobese: BMI<23 kg/m² and overweight or obese: BMI≥23 kg/m²). Clinical events during the follow-up including all-cause mortality and HF readmission were assessed.

Results: During the median follow-up of 828 days (interquartile range, 111-1,514 days), there were 595 cases of total mortality (31.7%), 600 cases of HF readmission (32.0%), and 934 cases of composite events (49.8%). In unadjusted analyses, higher NT-proBNP level was associated with all-cause mortality and composite events (all-cause mortality and HF readmission) in both patients with BMI<23 kg/m² and those with BMI≥23 kg/m². In adjusted analyses controlling for potential confounders, however, a higher NT-proBNP level was associated with all-cause mortality and composite events in patients with BMI<23 kg/m², but not in those with BMI≥23 kg/m².

Conclusions: The prognostic value of NT-proBNP was more significant in nonobese patients than in overweight and obese patients in this HF population. BMI should be considered when NT-proBNP is used for risk estimation in HF patients.