From the Guidelines
Obesity is associated with lower levels of pro brain natriuretic peptide (pro BNP) in patients with heart failure (HF).
Key Findings
- Studies have consistently shown that obese patients with HF have lower levels of BNP and NT-proBNP compared to non-obese patients 1.
- The lower levels of BNP in obese patients may be due to increased clearance of active natriuretic peptides by adipocytes, as well as the effects of pharmacological treatment for hypertension and coronary artery disease 1.
- A negative relationship between BMI and NT-proBNP has been observed, even after adjusting for covariates known to affect natriuretic peptide concentrations 1.
- The use of natriuretic peptides as diagnostic criteria may need to be adjusted in obese patients, as their lower levels may lead to underdiagnosis of HF 1.
Clinical Implications
- Clinicians should be aware of the potential for lower BNP levels in obese patients with HF, and consider using alternative diagnostic criteria or adjusting the threshold values for BNP and NT-proBNP 1.
- The relationship between obesity and BNP levels should be taken into account when interpreting natriuretic peptide biomarker levels in patients with HF, particularly in the context of clinical trials or diagnosis 1.
- Further research is needed to fully understand the mechanisms underlying the relationship between obesity and BNP levels, and to develop more effective diagnostic and therapeutic strategies for obese patients with HF.
From the Research
Effect of Obesity on Pro BNP Levels
- Obesity is associated with lower B-type natriuretic peptide (BNP) levels in healthy individuals and patients with chronic congestive heart failure (CHF) 2.
- Studies have shown that NT-proBNP and BNP levels decrease with increasing body mass index (BMI) 2, 3, 4.
- The inverse relationship between BMI and both NT-proBNP and BNP remains even after adjusting for covariates known to affect BNP levels 2.
Mechanism of Natriuretic Peptide Suppression in Obesity
- The mechanism of natriuretic peptide suppression in obese patients is not fully understood, but it is thought to be related to factors other than cardiac status 3.
- Obese patients have higher left ventricular end diastolic pressures (LVEDP) despite having lower BNP and NT-proBNP levels, suggesting that these peptides are not reliable surrogates for cardiac filling pressures or volumes 3.
Clinical Implications of Lower Pro BNP Levels in Obesity
- Lower NT-proBNP and BNP levels in obese patients may lead to reduced sensitivity of these biomarkers for diagnosing heart failure 2, 4.
- However, achieving NT-proBNP levels ≤1000 pg/mL has favorable prognostic implications, irrespective of obesity status 5.
- Obesity may modify the relationship between NT-proBNP and mortality, with obese individuals having a lower risk of mortality associated with high NT-proBNP levels 6.
Key Findings
- NT-proBNP levels are inversely related to BMI, with the largest decrease in NT-proBNP seen in the highest obesity category 4.
- Obese patients have a greater risk of developing adverse cardiovascular events, despite having lower NT-proBNP levels 5.
- NT-proBNP is the strongest predictor of adverse cardiovascular event risk in both obese and nonobese patients 5.