title: Relationship between different fasting-based insulin sensitivity indices in obese children and adolescents.
abstract: OBJECTIVE
  To evaluate insulin sensitivity from data obtained from baseline values and from an oral glucose tolerance test (OGTT) in normal and obese children and adolescents.
  
  
  METHODS
  We recruited 89 children 4-10 years old and 82 adolescents 11-18 years old divided into moderately obese (Mod OB), severely obese (Severe OB), and non-obese (Non-OB) controls. We evaluated the relationship between four simple measures of insulin sensitivity: homeostatic model assessment (HOMA-IR), quantitative insulin sensitivity check index (QUICKI), fasting glucose to insulin ratio (FGIR), and fasting insulin resistance index (FIRI), with an insulin sensitivity measure derived from the standard 2-hour OGTT, the composite whole body insulin sensitivity index (ISI Comp).
  
  
  RESULTS
  The strongest correlation was between QUICKI and ISI Comp and between FGIR and ISI Comp, (correlations [r] 0.81-0.85 in the Mod OB and 0.63-0.67 in the Severe OB). The relationship between HOMA-IR and ISI Comp and between FIRI and ISI Comp did not appear to be as strong (correlations [r] -0.36 and -0.53 in Mod OB and Severe OB, respectively). Moderately obese and severely obese children had fasting and 2-hour insulin levels 2-3 fold higher than the control group.
  
  
  CONCLUSIONS
  QUICKI and FGIR, are strongly correlated with OGTT measures of insulin sensitivity in children and adolescents with different degrees of obesity. These simple fasting-based indices may help the pediatrician identify patients at risk of developing insulin resistance.
authors.affiliation: Pediatric Endocrine Unit, Department of Pediatrics, Hospital de Clinicas Caracas, Venezuela. petergunczler@hotmail.com
authors.forename: Peter
authors.initials: P
authors.lastname: Gunczler
authors.forename: Roberto
authors.initials: R
authors.lastname: Lanes
mesh_terms: D000293:Adolescent; D001786:Blood Glucose / Q000032:analysis; D002648:Child; D005215:Fasting / Q000097:blood*; D005260:Female; D005951:Glucose Tolerance Test / Q000379:methods; D006801:Humans; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D009765:Obesity / Q000097:blood*; D012016:Reference Values; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric
chemical_list: D001786:Blood Glucose; D007328:Insulin