Insulin Resistance, Impaired fasting, Glucose Intolerance and Type II Diabetes Mellitus in Overweight and Obese Children in Abu Dhabi

Abstract

Background: Obesity is increasingly seen in children and youth. It is linked to major health concerns including glucose intolerance and type II diabetes. This study aims to assess the prevalence of impaired glucose tolerance, impaired fasting, and insulin resistance and type 2 DM in overweight and obese children and adolescents presenting to our pediatric endocrinology clinic in Abu Dhabi, UAE. Methods: Overweight and obese children and adolescents are enrolled in an observational, cross-sectional study. Patients had detailed demographic and family history taken. Standardized weight, height, BMI and waist circumference were recorded. Laboratory tests included fasting glucose, insulin and HbA1c were done. Patients who had high fasting glucose or HbA1c had standard oral glucose tolerance test. Insulin sensitivity was assessed by applying HOMA-index. Results: A total of 216 patients (121 males) were enrolled; mean age was 10.58 ± 2.9 years. 93% were obese, 7% overweight; and173 had a waist circumference ≥ 90^th centile. 147 patients (74.2%) were insulin resistant; 7 patients were diagnosed with diabetes (6 had HbA1c above 6.5, 1 had 2 consecutive glucose measurements above 7 mmol/L), and 87 (43.5%) had an indication for OGTT: 26 elevated fasting, 50 elevated HbA1c, and 11 had both. 15 patients (8.2%) had impaired glucose tolerance and 37 (18.1) had impaired fasting. 5 patients of 11 with impaired fasting and elevated Hba1c (45.5%) and 8 patients of 50 elevated HbA1c (17.4%) had glucose intolerance. Conclusions: Insulin resistance is common in overweight and obese children and is more commonly seen in older children with high weight, height and waist circumference. Higher yield of glucose intolerance is obtained when screening utilized combination of high fasting glucose and HbA1c.