title: [Evaluation of serum insulin levels after an oral glucose load for the diagnosis of insulin resistance].
abstract: BACKGROUND
  In our country, the assessment of insulin resistance (IR) measuring serum insulin levels at 60 and 120 minutes after a 75 g oral glucose tolerance test (OGTT), is usual. However, there is no information about the distribution of serum insulin levels in the Chilean population.
  
  
  OBJECTIVE
  To assess the distribution of serum insulin levels at 60 and 120 minutes during OGTTs and suggest a statistical cut-off point to estimate the degree of IR.
  
  
  METHODS
  Retrospective analysis of 1815 OGTTs performed in non-diabetic subjects aged between 18 and 75 years, at a university medical center. HOMA-IR (Homeostasis Model Assessment), insulin sensitivity index of Matsuda (ISI-Composite), and their correlation with serum insulin levels at 60 and 120 minutes were calculated.
  
  
  RESULTS
  The 75th percentiles for serum insulin levels at 60 and 120 minutes were 127 and 81 µU/mL, respectively. There was a high correlation between HOMA-IR and ISI-Composite (r = -089, p < 0.001). There was a weaker although significant correlation between HOMA-IR and ISI-Composite and insulin levels at 60 (r = 0.56 and -0.79 respectively, p < 0,001) and 120 minutes (r = 0.54 and -0.75 respectively, p < 0,001).
  
  
  CONCLUSIONS
  We propose 60 and 120 min serum insulin levels of 130 and 80 µU/mL respectively, as cut-off values for normality during OGTT in Chilean normoglycemic individuals.
authors.forename: Constanza
authors.initials: C
authors.lastname: Arancibia
authors.forename: José
authors.initials: J
authors.lastname: Galgani
authors.forename: Juan P
authors.initials: JP
authors.lastname: Valderas
authors.forename: Mauricio
authors.initials: M
authors.lastname: Morales
authors.forename: José Luis
authors.initials: JL
authors.lastname: Santos
authors.forename: Felipe
authors.initials: F
authors.lastname: Pollak
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005951:Glucose Tolerance Test; D006706:Homeostasis; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood / Q000175:diagnosis* / Q000503:physiopathology; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D007328:Insulin