Changes in B-Type Natriuretic Peptide and BMI Following Roux-en-Y Gastric Bypass Surgery

Obesity and attendant complications including type 2 diabetes mellitus, hypertension (HTN), and heart disease are worldwide epidemics with incompletely understood associations. Mechanisms underlying the association of HTN and obesity include upregulation of the renin-angiotensin-aldosterone system, sympathetic nervous system, insulin resistance, and adipose tissue activity, but a paradoxically downregulated cardiac natriuretic peptide system, cardiovascular system, and altered renal function (1). Recent studies suggest that natriuretic peptide deficiency may provide a link between obesity-related HTN and insulin resistance (2). Weight loss through bariatric surgery has reduced or eliminated HTN in multiple randomized controlled trials, perhaps through decreased plasma volume, but other mechanisms including changes in the cardiac natriuretic peptide system and lipolysis remain obscure (3). Understanding natriuretic peptide concentration changes following Roux-en-Y gastric bypass (RYGB) surgery may help elucidate the mechanism and impact of paradoxically low concentrations in obesity. We characterized changes in B-type natriuretic peptide (BNP) and N-telopeptide pro-BNP (NT-proBNP) in obese subjects after RYGB surgery by measuring concentrations at baseline and 6, 12, and 24 months postoperatively to enhance our understanding of BNP’s role in weight loss and hemodynamics in this population.