Objective: The role of incretins in type 2 diabetes (T2D) is controversial. This study investigated the association between incretin levels in obese Korean children and adolescents with T2D.
Patients and methods: We performed a 2-h oral glucose tolerance test in obese children and adolescents with T2D and with normal glucose tolerance. Twelve obese children and adolescents with newly diagnosed T2D (DM group) and 12 obese age-matched subjects without T2D (NDM group) were included. An oral glucose tolerance test (OGTT) was conducted and insulin, C-peptide, glucagon, glucagon-like peptide 1 (GLP1), and glucose-dependent insulinotropic polypeptide (GIP) were measured during the OGTT. Follow-up OGTT was done to six patients of the DM group (DM2 group) after 3 days discontinuation of oral hypoglycaemic agent.
Results: The mean age of the patients was 13.8±2.0 years, and the mean BMI Z-score was 2.1±0.5. DM and NDM groups were comparable in age, sex, BMI Z-score, and waist:hip ratio. The DM group had significantly lower homeostasis model assessment of beta (HOMA-β) and insulinogenic index (IGI) values (P<0.001). The HOMA of insulin resistance (HOMA-IR) index was not different between the two groups. Insulin and C-peptide secretions were significantly lower in the DM group than in the NDM group (P<0.001). Total GLP1 (TGLP1) secretion was significantly higher in the DM group while intact GLP1 (iGLP1) and GIP secretion values were not significantly different between the two groups. Comparing DM and DM2 groups, FBS, BMI, HbA1c, HOMA-IR, and IGI values were significantly lower in the DM group than in the DM2 group (P<0.05). HOMA-β was higher in the DM group than in the DM2 group (P=0.017). TGLP1 and GIP secretion values were not significantly different in the DM and DM2 group, however, iGLP1 secretion was significantly lower in the DM2 group than in the DM group (P=0.017). Comparing DM2 and NDM groups, TGLP1 secretion was significantly higher in the DM2 group than in the NDM group (P=0.04), however, iGLP1 and GIP secretion values were not significantly different.
Conclusion: Impaired insulin secretion might be important in the pathogenesis of T2D in obese Korean children and adolescents, however, which may not be attributed to incretin secretion. Although, patients had wash-out period, oral hypoglycaemic agent might be able to influence on incretin secretion.
01 - 03 Oct 2015
European Society for Paediatric Endocrinology