Endocrine Abstracts

Background: Oral glucose tolerance test (OGTT) is usually used to determine carbohydrate metabolism abnormalities in overweight patients. Measurement of glucose and insulin level on demanded 0 and 120 minute and some additional minutes could give information for obesity treatment choice and for patients’ follow-up. The aim of our study is to assess whether glucose and insulin level measurement during oral glucose tolerance test could be used as predictors for treatment efficacy in obese patients.

Materials and methods: 107 patients (55 women, 52 men, mean age 44.01±12.87years) with mean weight 99.07±18.73 kg, mean BMI 34.86±6.0 kg/sq.m and mean HbA1c 5.75±0.58% underwent OGTT at the end of treatment period. Additional measurements of glucose were performed on minute 60 and 180 as well as measurement of insulin level on 0, 60th, 120th, 180th minute. HOMA-IR was calculated. Patients had received different treatment for weight management including diet and exercise instruction, metformin and GLP1 analogues for the previous six months. A correlation between glucose, insulin level on different minutes and treatment efficacy results was assessed.

Results: Basal minute glucose level shows moderate significant correlation with weight decrease (phi=0.61, P<0.05). Glucose level on first hour is presenting with more strong correlation (phi=0.72, P<0.05) and the second hour blood glucose shows not significant correlation (phi=0.47, P=0.24). Insulin on 0, 60 and 120 min is presenting with strong correlation of weight loss (P<0.05). HOMA-IR index is also correlating with therapeutic answer especially in metformin receiving group but not in GLP1 analogues treated group (P<0.05). No difference was found depending on age, gender, and weight of patients and with weight at the start of the study.

Conclusion: Glucose and insulin level during OGTT could be used as predictors for future therapeutic efficacy and for treatment choice in obese patient. Defining such predicting factors is useful for clinical practice and should be objective of research.