Early-phase insulin hypersecretion associated with weight loss outcome after LSG: a prospective cohort study in Asian...

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.

The objective of this study was to explore whether preoperative insulin secretion could be associated with weight loss after LSG in patients with obesity.

This is a single-center prospective cohort study conducted in a university hospital.

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.

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 (C₃₀) was significantly negatively correlated with %EWL (β = -.37, P < .001) and %TWL (β = -.28, P = .011). Univariate logistic regression analysis showed that preoperative C₃₀ was associated with %EWL ≥75% and %TWL ≥35% after LSG. According to multiple logistic regression analysis, patients with a low preoperative C₃₀ had an 8-fold higher %TWL ≥35% after LSG than those with a high C₃₀ (odds ratio: 8.41 [95% confidence interval: 1.46-48.58], P = .017). Similarly, patients with a low preoperative C₃₀ had a 7-fold higher EWL% ≥75% after LSG than patients with a high C₃₀ (odds ratio: 7.25 [95% confidence interval: 1.11-47.50], P = .039).

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.