Obesity and BNP

Q: Obesity __________ natriuretic peptide levels? (select one)

A) decreases

B) increases

Answer: A

The objective of this question is to highlight the confounders while interpreting natriuretic peptide levels i.e., BNP or NT-proBNP. Two major factors are:

• Renal insufficiency - causes elevated BNP and even greater elevated NT-proBNP levels.
• Obesity - depresses BNP and NT-proBNP levels.

Also, normal natriuretic peptide levels do not exclude the diagnosis of Heart Failure with preserved Ejection Fraction (HFpEF).

#cardiology

References:

Horwich TB, Hamilton MA, Fonarow GC. B-type natriuretic peptide levels in obese patients with advanced heart failure. J Am Coll Cardiol. 2006 Jan 3;47(1):85-90. doi: 10.1016/j.jacc.2005.08.050. Epub 2005 Dec 15. PMID: 16386669.

Takase H, Dohi Y. Kidney function crucially affects B-type natriuretic peptide (BNP), N-terminal proBNP and their relationship. Eur J Clin Invest. 2014;44(3):303-8. doi: 10.1111/eci.12234. Epub 2014 Jan 20. PMID: 24372567.