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.

Obesity and diabetes—Not only a simple link between two epidemics

“…Obesity is the most important culprit of insulin resistance, which appears early in the disease, and is primarily compensated by hyperinsulinaemia . Insulin resistance is more often in obese children with high weight, height, and waist circumference . Occurrence of obesity is among others related to the early adiposity rebound at the age of 3 years that was shown to lead to an increased body mass index (BMI) when adolescent .…”

“…In American Indian and Alaska Native adults, the percentage of obesity among T2D patients rose by 58% between 1976 and 2004 . In a study performed in Iraq in 2007, it was proven that among all anthropometric variables, waist circumference is the most sensitive predictor for T2D …”

“…A recent study conducted in Abu Dhabi among 216 obese (90%) or overweight (7%) patients highlighted that older children with higher height‐for‐age, weight‐for‐age, and waist circumference‐for‐age have a higher insulin resistance . In this group, already, 7% had diabetes, 8.2% had IGT, and 18.1% were examined with impaired fasting glucose …”

“…[1][2][3][4] Insulin resistance is more often in obese children with high weight, height, and waist circumference. 5 Occurrence of obesity is among others related to the early adiposity rebound at the age of 3 years that was shown to lead to an increased body mass index (BMI) when adolescent. 2 Obesity combined with insulin deficiency leads to the development of T2D.…”

“…7 In a study performed in Iraq in 2007, it was proven that among all anthropometric variables, waist circumference is the most sensitive predictor for T2D. 5 Other studies showed that the distribution of fat tissue is the crucial factor to develop insulin resistance, independently of the stage of obesity. 3,11 The authors compared obese adolescents with a similar rate of adiposity, and those with impaired glucose tolerance (IGT) were more insulin resistant than adolescents with normal glucose tolerance.…”