Temporal changes in glucose homeostasis and incretin hormone response at 1 and 6 months after laparoscopic sleeve gastrectomy

Abstract

Background: Bariatric surgery is an effective treatment for morbid obesity. Current literature reports significant improvements in glucose homeostasis after malabsorptive surgery. There is limited evidence on the effects of laparoscopic sleeve gastrectomy (SG) on glucose-insulin homeostasis and postoperative incretin hormone response. The objective of this study was to examine the metabolic effects of SG on temporal changes in insulin and glucose homeostasis, incretin hormones and hepatic insulin clearance in patients with impaired glucose tolerance (IGT) and type 2 diabetes (T2 DM).

Methods: A nonrandomized prospective study comprising 22 participants undergoing SG (body mass index [BMI] 50.1 kg/m(2), glycated hemoglobin [HbA1c] 53 mmol/mol) and 15 participants undergoing biliopancreatic diversion (BPD) (BMI 62.1 kg/m(2), HbA1c 58 mmol/mol). Serial measurements of glucose, insulin, C-peptide, glucagon like peptide-1 (GLP-1) and glucose-dependent insulinotropic hormone (GIP) were performed during oral glucose tolerance testing preoperatively and 1 and 6 months postoperatively. Areas under the curve (AUC) were examined at 30, 60, and 120 minutes.

Results: Within the SG group, significant improvements were observed respectively at 1 and 6 months in glucose control (HbA1c: -0.9%, -1.3%), measures of insulin sensitivity (fasting insulin: -4.8 mU/L, -8.5 mU/L; fasting C-peptide: -0.6 pmol/L, -1.1 pmol/L; Homeostasis Model Assessment [HOMA-IR]: -0.144, -0.174; HOMA %S:+29.6,+92.4), hepatic insulin clearance (+0.07,+0.13) and postprandial GLP-1 response (AUC0-30 pmol h L(-1):+300,+331, AUC0-60:+300,+294, AUC0-120:+316,+295). These results were comparable to the BPD group.

Conclusions: SG is associated with significant early improvements in insulin sensitivity and incretin hormone response and results in significant improvements in IGT/T2 DM.

Keywords: Biliopancreatic diversion; Obesity; Sleeve gastrectomy; Type 2 diabetes mellitus.