Abstract 838: N-terminal Pro-brain Natriuretic Peptide Levels and Obesity in Patients With Acute Myocardial Infarction. Data From the Rico Survey
Objective. Recent findings reported intriguing relationships between obesity and natriuretic peptides. In patients with acute myocardial infarction (MI), we aimed to investigate the relation between body mass index (BMI) and N-Terminal pro Brain Natriuretic Peptide (NT-proBNP) level.
Patients and methods. From a French regional survey for acute MI, we formed 739 triplets of patients (n=2217) with an acute MI, matched with respect to age, gender, and renal function (MDRD, modification of diet in renal disease), each classified for BMI groups as obese (BMI> 30 kg/m2), overweight (BMI 25–29.9 kg/m2) and normal (BMI 20 –24.9 kg/m2). Blood samples were taken on admission to assess NT-proBNP levels.
Results. Among the 2217 participants, mean age was 68±12 years, 80% were male and MDRD was 75±26 ml/min/1.73m2. Higher prevalence of CV risk factors (hypertension, diabetes and dyslipidemia) was found across the overweight and obese groups. Admission CRP levels were increased in obese patients. Clinical heart failure on admission and LVEF were similar for the 3 groups. When compared with normal BMI, median NT-proBNP levels dramatically decreased by about 20% in overweight and 60 % in obese (1046 vs 839 and 444 pg/ml, respectively, p<0.001). An inverse relationship was found between the propeptide values and BMI (r=−0.20, p<0.0001). By multivariable linear regression, BMI as a continuous variable remained a predictor of logNT-proBNP level, even when adjusted for potential confounders. CV mortality at 1-Y follow-up was similar for the 3 BMI groups (p=0.691). By multivariate logistic regression analysis, logNT-proBNP predicted CV mortality in normal (OR(95%CI), 2.24(1.29 –3.89)) and overweight (OR(95%CI): 6.11(2.75–13.60)) patients, even when adjusted for confounders (GRACE risk score, LVEF, and prior MI). However, in obese patients, the propeptide levels failed to retain its prognostic capacity (OR(95%CI): 1.44(0.88 –2.35)).
Conclusions. In this large contemporary non-selected cohort of MI patients, NT-proBNP levels were dramatically reduced in obese patients even matched for age, renal function and gender. Moreover, in obese patients with acute MI, the significance of the propeptide level as an independent prognostic factor remains to be determined.