title: Glucose tolerance status in 510 children and adolescents attending an obesity clinic in Central Italy.
abstract: Childhood obesity is epidemic in developed countries and is accompanied by an increase in the prevalence of type 2 diabetes (T2DM).
  
  
  OBJECTIVE
  Establish prevalence of glucose metabolism alterations in a large sample of overweight/obese children and adolescents from Central Italy.
  
  
  METHODS
  The study group included 510 overweight/obese subjects (3-18 yr). Oral glucose tolerance test (OGTT) was performed with glucose and insulin determination. Homeostatic model assessment of insulin resistance (HOMA-IR) and insulin sensitivity index (ISI) were derived from fasting and OGTT measurements. Beta-cell function was estimated by insulinogenic index. Fat mass was measured by dual-energy x-ray absorptiometry.
  
  
  RESULTS
  Glucose metabolism alterations were detected in 12.4% of patients. Impaired glucose tolerance (IGT) was the most frequent alteration (11.2%), with a higher prevalence in adolescents than in children (14.8 vs. 4.1%, p < 0.001); silent T2DM was identified in two adolescents (0.4%). HOMA-IR and glucose-stimulated insulin levels were higher in patients with IGT than individuals with normal glucose tolerance (HOMA-IR = 4.4 +/- 2.5 vs. 3.4 +/- 2.3, p = 0.001). Fat mass percentage and insulinogenic index were not different between the two groups. In multivariate analysis, age, fasting glucose, and insulin resistance influenced independently plasma glucose at 120 min of OGTT. Individuals with combined impaired fasting glucose/IGT (IFG/IGT) and T2DM were older and had reduced plasma insulin values at OGTT when compared to patients with simple IGT.
  
  
  CONCLUSIONS
  Glucose metabolism alterations are frequently found among children and adolescents with overweight/obesity from Central Italy. Age, fasting glucose, and insulin resistance are main predictors of IGT. We suggest the use of OGTT as a screening tool in obese European adolescents.
authors.affiliation: Endocrinology and Diabetes Unit, Department of Paediatric Medicine, Bambino Gesù Children's Hospital IRCCS, Rome, Italy. cbrufani@libero.it
authors.forename: Claudia
authors.initials: C
authors.lastname: Brufani
authors.forename: Paolo
authors.initials: P
authors.lastname: Ciampalini
authors.forename: Armando
authors.initials: A
authors.lastname: Grossi
authors.forename: Rossana
authors.initials: R
authors.lastname: Fiori
authors.forename: Danilo
authors.initials: D
authors.lastname: Fintini
authors.forename: Alberto
authors.initials: A
authors.lastname: Tozzi
authors.forename: Marco
authors.initials: M
authors.lastname: Cappa
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Barbetti
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D002648:Child; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000453:epidemiology*; D005260:Female; D005947:Glucose / Q000378:metabolism*; D018149:Glucose Intolerance / Q000097:blood / Q000453:epidemiology*; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D050417:Insulin-Secreting Cells / Q000502:physiology; D007558:Italy / Q000453:epidemiology; D008297:Male; D009765:Obesity / Q000097:blood / Q000453:epidemiology*
chemical_list: D007328:Insulin; D005947:Glucose