title: [Normal plasma insulin and HOMA values among Chilean children and adolescents].
abstract: BACKGROUND
  Plasma insulin and HOMA (homeostasis model assessment) index, used to determine insulin resistance, do not have local standard values for children and adolescents in Chile.
  
  
  OBJECTIVE
  To establish the normal reference intervals for insulin and HOMA in children and adolescents aged 10-15 years, according to sex and puberal maturation.
  
  
  METHODS
  A cross-sectional study of 2,153 children and adolescents from Puente Alto County was performed, during 2009 and 2010. Anthropometry and self-report of puberal maturation were assessed. Fasting glucose (hexoquinase) and insulin blood levels (chemiluminiscence), were determined and HOMA index was calculated. Percentile distributions of these variables were calculated.
  
  
  RESULTS
  The reference group included only subjects with normal body mass index and fasting blood glucose (n = 1,192). Girls had higher insulin and HOMA values than boys (12.5 ± 6.0 and 9.1 ± 4.9 μϋ/mL (p < 0.01) and 2.7 ± 1.4 and 2.1 ± 1,1 (p < 0.01), respectively). Subjects with Tanner I and II pubertal stages had lower insulin and HOMA mean values than subjects with Tanner III and IV (9.0 ± 4.3 and 12.5 ± 6.2μϋ/ml (p < 0.01) and2.0 ± 1 and2.8 ± 1.4 (p < 0.01), respectively).
  
  
  CONCLUSIONS
  The 90th percentile of insulin and HOMA distributions according to sex and maturation, was selected as the upper cut-off point to identify individuals with insulin resistance. HOMA cutoff point for Tanner I and II boys was 3.2, for Tanner I and II girls was 4.1, for Tanner III and IV boys was 4.2 and for Tanner III and IV girls was 5.0.
authors.affiliation: Departamento Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Salesa
authors.initials: S
authors.lastname: Barja
authors.forename: Pilar
authors.initials: P
authors.lastname: Arnaiz
authors.forename: Angélica
authors.initials: A
authors.lastname: Domínguez
authors.forename: Luis
authors.initials: L
authors.lastname: Villarroel
authors.forename: Berta
authors.initials: B
authors.lastname: Cassis
authors.forename: Oscar
authors.initials: O
authors.lastname: Castillo
authors.forename: Gianina
authors.initials: G
authors.lastname: Salomó
authors.forename: Marcelo
authors.initials: M
authors.lastname: Farías
authors.forename: Manuela
authors.initials: M
authors.lastname: Goycoolea
authors.forename: Teresa
authors.initials: T
authors.lastname: Quiroga
authors.forename: Francisco
authors.initials: F
authors.lastname: Mardones
mesh_terms: D000293:Adolescent; D001786:Blood Glucose / Q000502:physiology*; D015992:Body Mass Index; D002648:Child; D002677:Chile / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005215:Fasting / Q000097:blood; D005260:Female; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D011627:Puberty / Q000502:physiology*; D012016:Reference Values; D012737:Sex Factors; D018709:Statistics, Nonparametric
chemical_list: D001786:Blood Glucose; D007328:Insulin