Application of the intravenous glucose tolerance test and the minimal model to patients with insulinoma: Insulin sensitivity (Si) and glucose effectiveness (Sg) before and after surgical excision

Abstract

Background: The unmodified frequently sampled intravenous glucose tolerance test (FSIGT) has not previously been used to assess insulin/glucose kinetics in patients with insulinoma. Objective: To measure insulin sensitivity (Si) and glucose effectiveness (Sg) by means of the FSIGT in patients with insulinoma, before and after surgical removal of the tumour. Subjects and methods: FSIGTs were performed in five patients, before and approximately 3 months post-surgery, and in 11 controls. Si and Sg were estimated using Minimal Model computer analysis of dynamic glucose and insulin data. Results: Si was lower in insulinoma patients before, compared with after surgery (3.37 ± 0.62 vs. 6.24 ± 1.09 ..