Determinants of low levels of brain natriuretic peptide in morbid obesity

morbid obesity is associated with cardiovascular comorbidity. A noteworthy feature of this relationship could regard low levels of brain natriuretic peptide (BNP). The study investigates the relationship between BNP and obesity-related markers in a morbid obese population, along with echocardiographic and vascular parameters.

in 154 morbid obese patients we evaluated anthropometric parameters, glycometabolic/lipid profile, bioimpedentiometry, echocardiography, visceral fat area and flow-mediated dilation (FMD) by ultrasonography.

we divided population in two groups on the basis of median BMI levels; patients with higher BMI had significantly lower BNP (p = .008), FMD (p = .014) and HDL-C (p = .001) and showed a more impaired heart function. A similar trend emerged subdividing patients on the basis of median visceral fat area. BNP showed a significant inverse correlation with BMI (p < .001), left ventricular mass (p = .026) and inter-ventricular septum thickness (p = .007) and a significant positive correlation with FMD (p = .008), HDL-C (p = .022), and ejection fraction (p = .013). BMI and triglycerides were independent predictors of BNP levels.

patients with higher BMI show lower BNP levels associated with greater total body fat amount. The correlation of BNP with endothelium-dependent vasodilation and cardiac impairment could represent another link between obesity and cardiovascular damage.