Effect of Roux-en-Y Gastric Bypass vs Sleeve Gastrectomy on Glucose and Gut Hormones: a Prospective Randomised Trial

Laparoscopic Roux-en-Y gastric bypass (LRYGB) is the most common bariatric technique. Laparoscopic sleeve gastrectomy (LSG) is a restrictive procedure; the metabolic and endocrine effects of which remain unknown. We compared the effects of both procedures on glucose metabolism and fasting and meal-stimulated gut hormone levels. Seven patients were randomised to LRYGB and eight to LSG. All patients were evaluated before and at 3 and 12 months postoperatively. Plasma levels of glucose, insulin, ghrelin, leptin, peptide YY (PYY), GLP-1 and pancreatic polypeptide were measured before and after 10 and 60 min of a standard test meal ingestion. Age, body mass index and preoperative hormone levels were similar in both groups. A significant reduction of plasma glucose and insulin levels was observed after surgery. Moreover, a normalisation of homeostatic model assessment for insulin resistance value was also seen after both procedures. The fasting and postprandial leptin levels were significantly lower in the LRYGB group. LSG was followed by a significant reduction in fasting ghrelin levels. In the LRYGB group, GLP-1 levels increased significantly after the test meal. LRYGB and LSG markedly improved glucose homeostasis. Only LSG decreased fasting and postprandial ghrelin levels, whereas GLP-1 and PYY levels increased similarly after both procedures.