BNP in overweight and obese patients with heart failure: an analysis based on the BNP-LV diastolic wall stress relationship.
BACKGROUND
Suppressed plasma B-type natriuretic peptide (BNP) levels have been reported in obese individuals with heart failure (HF). However, the precise mechanism and significance of this relationship in the clinical setting of HF are unknown. Recently, we reported a close association between BNP levels and left ventricular end-diastolic wall stress (EDWS) as the underlying mechanism of BNP secretion; therefore, we investigated the relationship between BMI and plasma BNP levels in HF while adjusting for EDWS.


RESULTS
In 245 consecutive patients who presented with HF, we measured plasma BNP levels and performed echocardiography and cardiac catheterization. Meridional EDWS was calculated from echocardiographic and hemodynamic parameters. The body mass index (BMI) for the total population was 22.9 +/- 0.2 kg/m2; 21% were lean (BMI < 20) and 27% overweight and obese (BMI > or = 25). The correlation between plasma BNP and EDWS [r = 0.771 (P <.001)] was more robust than any other echocardiographic or hemodynamic parameter as well as any patient's characteristics. By a univariate analysis, BMI was inversely correlated with both BNP levels and EDWS (P <.001 in both). However, a multivariable regression analysis that took into account EDWS demonstrated a significant inverse association between BMI and BNP (P <.001).


CONCLUSIONS
The present study demonstrates that BMI determines the BNP level in a manner that is independent of the hemodynamic load in patients with HF. Overweight and obesity should be considered to be associated with the interindividual variability of plasma BNP levels in the diagnosis and management of HF patients.
Iwanaga
Yoshitaka
Y
Division of Cardiology, National Cardiovascular Center, Suita, Japan.
Kihara
Yasuki
Y
Niizuma
Shinichiro
S
Noguchi
Teruo
T
Nonogi
Hiroshi
H
Kita
Toru
T
Goto
Yoichi
Y
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000150:complications; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D009765:Obesity / Q000097:blood* / Q000150:complications; D050177:Overweight / Q000097:blood* / Q000150:complications; D018487:Ventricular Dysfunction, Left / Q000097:blood* / Q000150:complications; D016277:Ventricular Function, Left / Q000502:physiology
D015415:Biomarkers; D020097:Natriuretic Peptide, Brain