Metabolic Bariatric Surgical Procedures Are Associated with Increased NT-ProBNP Levels – a retrospective cohort study

Introduction The heart secretes B-type natriuretic peptide (BNP) in response to myocardial wall stretch. BNP levels are inversely associated with obesity, and a reduced natriuretic peptide responsiveness has been described in individuals with obesity. Diet-induced weight loss has been reported to decrease or have no significant effect on BNP levels, whereas studies evaluating BNP levels following metabolic bariatric surgery (MBS) have yielded inconsistent results, often based on relatively small cohorts. In the present study, we assessed NT-proBNP levels in a large cohort of patients undergoing bariatric surgery. Methods NT-proBNP levels in patients (n = 913) who underwent MBS at Uppsala University Hospital between 2015 and 2020 was evaluated during 1 year. All three procedures performed at this center were included: Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and biliopancreatic diversion with duodenal switch (BPD-DS). Biometric measurements and blood samples, including NT-proBNP, were obtained preoperatively and at 6 and 12 months postoperatively. Conclusion and Discussion NT-proBNP levels increased in all surgical groups at 6 months and remained elevated at 12 months. RYGB increased from 63.2(SD 105.4) to 109.3(SD 132.5) ng/L at 1 year, SG from 59.1(SD 55.3) to 82.3(SD 63.9) ng/L, and BPD-DS from 121.1(SD 239.6) to 359.3(SD 776.3) ng/L. The magnitude of change was not correlated with the degree of weight loss or change in HbA1c, which differed between groups. Furthermore, the type of surgical procedure did not significantly influence the extent of NT-proBNP change. This likely sustained alteration in natriuretic peptide levels should be taken into account when assessing cardiac status in this patient population.