The effect of sleeve gastrectomy on GLP-1 secretion and gastric emptying: a prospective study

Background: Rapid gastric emptying has been proposed to justify the increase in glucagon-like polypeptide-1 (GLP-1) after laparoscopic sleeve gastrectomy (LSG). Objectives: To assess gastric emptying changes after LSG and their relationship with GLP-1 secretion. Setting: San Salvatore Hospital general surgery unit, University of L'Aquila, Italy. Methods: 52 patients underwent gastric emptying scintigraphy for liquid and solid foods, before and 3 months after LSG. Twenty-six patients were in the liquid group (L group) and the remaining in the solid group (S group). We evaluated the half time of gastric emptying (T-1/2) and percentage of gastric retention (%GR) at 15, 30, and 60 minutes for liquids and at 30, 60, 90, and 120 minutes for solids. GLP-1 plasma concentrations were measured in each group before and after LSG and related to %GR. Statistical analysis was performed by X2 test and Pearson correlation(r). Results: After surgery, T-1/2 was significantly accelerated: 15.2 +/- 13 min and 33.5 +/- 18 min in the L group and S group, respectively (P < .05). In both groups, GLP-1 plasma concentrations were increased at each blood sampling time: 2.91 +/- 2.9 pg/mL, 3.06 +/- 3.1 pg/mL and 3.21 +/- 2.6 pg/mL at 15, 30, and 60 minutes, respectively, (P < .05) for L group and 2.72 +/- 1.5 pg/mL, 2.89 +/- 2.1 pg/mL, 2.93 +/- 1.8 pg/mL, and 2.95 +/- 1.9 pg/mL at 30, 60, 90, and 120 minutes, respectively, (P < .05) for the S group. After LSG, GLP-1 and %GR presented a negative linear correlation (r) at each blood sampling time in both groups. Conclusion: The rapid gastric emptying 3 months after LSG upregulates the production of GLP-1 in the distal bowel. Further studies are needed to confirm these findings. (C) 2017 American Society for Metabolic and Bariatric Surgery. All rights reserved.