Early-phase insulin hypersecretion associated with weight loss outcome after LSG: a prospective cohort study in Asian patients with BMI ≥28 kg/m 2 .

Background: Obesity has become a global problem that poses a serious threat to human health. Laparoscopic sleeve gastrectomy (LSG) is an effective long-term treatment. However, the weight loss of some patients after LSG is still insufficient. It is necessary to investigate the factors associated with inadequate weight loss after LSG.
Objective: The objective of this study was to explore whether preoperative insulin secretion could be associated with weight loss after LSG in patients with obesity.
Setting: This is a single-center prospective cohort study conducted in a university hospital.
Methods: Patients from a prospective database who underwent LSG were analyzed. All 178 participants underwent a 75-g oral glucose tolerance test (OGTT) to assess preoperative insulin and c-peptide secretion before LSG. The areas under the curve (AUCs) for glucose, insulin, and c-peptide were determined in the OGTT. The percentage of excess weight loss (%EWL) and the percentage of total weight loss (%TWL) were used to estimate the effect of weight loss after LSG. Regression models were used to assess the correlation between preoperative insulin and c-peptide secretion with %EWL ≥75% and TWL ≥35% at 12 months after LSG.
Results: The AUCs of insulin and c-peptide were significantly lower in the %EWL ≥75% and %TWL ≥35% groups at 0-30 minutes, 0-60 minutes, and 0-120 minutes during the OGTT. At 30, 60, and 120 minutes during the OGTT, c-peptide levels were significantly lower in the %EWL ≥75% group and %TWL ≥35% group. The preoperative c-peptide level at 30 minutes during the OGTT (C ₃₀ ) was significantly negatively correlated with %EWL (β = -.37, P < .001) and %TWL (β = -.28, P = .011). Univariate logistic regression analysis showed that preoperative C ₃₀ was associated with %EWL ≥75% and %TWL ≥35% after LSG. According to multiple logistic regression analysis, patients with a low preoperative C ₃₀ had an 8-fold higher %TWL ≥35% after LSG than those with a high C ₃₀ (odds ratio: 8.41 [95% confidence interval: 1.46-48.58], P = .017). Similarly, patients with a low preoperative C ₃₀ had a 7-fold higher EWL% ≥75% after LSG than patients with a high C ₃₀ (odds ratio: 7.25 [95% confidence interval: 1.11-47.50], P = .039).
Conclusions: The rate of weight loss after LSG is low among patients with preoperative hyperinsulinemia. The preoperative c-peptide level at 30 minutes during the OGTT is associated with weight loss after LSG.
(Copyright © 2022 American Society for Metabolic and Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)