Ghrelin, Leptin, and Glycemic Control After Sleeve Gastrectomy Versus Roux-en-Y Gastric Bypass-results of a Randomized Clinical Trial

Background: Sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) cause weight loss and metabolic improvement, but results of published studies are contradictory.

Objectives: The aim of this study was to compare the effects of SG and RYGB on ghrelin, leptin, and glucose homeostasis in a randomized controlled trial.

Setting: University hospital, Poland.

Methods: Seventy-two morbidly obese patients were randomly selected to undergo either SG (n = 36) or RYGB (n = 36). Fasting ghrelin, leptin, glucose, insulin, C-peptide, glucagon, glycated hemoglobin, and homeostasis model assessment of insulin resistance were assessed preoperatively and at 1, 6, and 12 months postoperatively. No differences were found in anthropometric and biochemical parameters between the study groups at baseline.

Results: Sixty-nine (95.8%) patients completed the study. Percentage of excess weight loss at 12 months was 67.6±19.3% after SG and 64.2±18.5% after RYGB (P>.05). Fasting ghrelin levels decreased 1 month after SG (from 76.8 pmol/L to 35.3 pmol/L; P<.05) and remained reduced until 12 months (41.6 pmol/L; P<.05) but increased 12 months after RYGB from 74.6 pmol/L to 130.2 pmol/L (P<.05). Leptin, glucose, insulin, and C-peptide concentrations and glycated hemoglobin and homeostasis model assessment of insulin resistance values decreased significantly in both groups during 12 months.

Conclusions: RYGB and SG induce comparable weight loss and improvement in metabolism of glucose. Ghrelin levels decrease after SG and increase after RYGB, but this difference does not affect similar outcomes of these procedures during 1-year follow-up. The contribution of ghrelin to weight loss or metabolic benefits after bariatric surgery is not straightforward, but rather influenced by multiple factors.