148 The effect of body mass index on serum n-terminal pro-b-type natriuretic peptide (2024)

Results The mean age was 71 ± 11 years, 63% male, mean BMI was 29 ± 6 kg/m2, and mean LVEF was 47 ± 14%. Around one-third had LVEF ≤40%. There were fewer patients with LVEF ≤40% in higher BMI categories (p <0.05). A quarter were in NYHA class III-IV. The median NT-proBNP level was 633 (170 – 1957) ng/L. Hypertension was common, especially in higher BMI categories (p <0.05). The median creatinine level was 95 (79 – 119) μmol/L.

There was an inverse relation between NT-proBNP and BMI: median (25th and 75th centile) NT-proBNP was: 1269 (324 – 3451) ng/L, 643 (171 – 1886) ng/L, and 402 (137 – 1244) ng/L in lean, overweight, and obese groups respectively (p <0.001). Within each NYHA class, there was an inverse relation between log NT-proBNP and LVEF across different BMI categories, with similar slope coefficients (-0.064 to -0.040, p <0.001). However, for any given LVEF, log NT-proBNP level was lower in higher BMI groups. Average intercepts on a plot with LVEF on the X axis and log NT-proBNP on the Y were 9.3, 8.7, and 8.2 kg/m2 in lean, overweight, and obese categories respectively (p <0.001).

There was an inverse relation between BMI as a continuous variable and NT-proBNP in the multivariable regression model (p <0.001). Each one unit increase in BMI (1 kg/m2) was associated with a 3% lower NT-proBNP level (p <0.001). Each SD increase in BMI (5.7 kg/m2 in our sample) was associated with a 10% lower NT-proBNP level (p <0.001). Age, sex, creatinine, LVEF, presence or absence of NYHA III-IV, and presence or absence of atrial fibrillation were also independent predictors of NT-proBNP levels (p <0.001). Among all the independent predictors identified, BMI had the weakest association with NT-proBNP.

Conclusion In patients referred for suspected HF, there is an inverse relation between BMI and NT-proBNP. The effect remains clinically significant even when relevant confounders are considered.

Log in via BCS