title: One-hour plasma glucose concentration during the OGTT: what does it tell about β-cell function relative to insulin sensitivity in overweight/obese children?
abstract: BACKGROUND
  In adults 1-h plasma glucose concentration cut-point of 155 mg/dL (8.6 mmol/L) during the oral glucose tolerance test (OGTT) is a strong predictor of future diabetes risk.
  
  
  OBJECTIVE
  We tested the hypothesis that a 1-h glucose concentration ≥155 mg/dL is associated with lower β-cell function in overweight/obese youth.
  
  
  METHODS
  One hundred and thirteen diabetes free overweight/obese youth aged 10-20 yr, underwent evaluation of β-cell function during a 2 h hyperglycemic clamp ∼225 mg/dL (12.5 mmol/L), and insulin sensitivity during a 3 h hyperinsulinemic-euglycemic clamp, and a standard 2 h OGTT. Body composition and abdominal adiposity were determined by DEXA and CT scan. The disposition index (DI) was calculated as the product of first-phase insulin secretion and insulin sensitivity. Subjects were divided into two categories of 1-h plasma glucose concentration: <155 mg/dL (n=69) and ≥155 mg/dL (n=44).
  
  
  RESULTS
  Youth with 1-h glucose ≥155 mg/dL had lower DI than those with 1-h glucose <155 mg/dL (295.1 ± 27.4 vs. 498.6 ± 37.7 mg/kg/min, p<0.001), independent of the glucose tolerance status. In multiple regression models, DI was the strongest contributor to 1-h glucose concentration explaining ∼21% of its variance.
  
  
  CONCLUSIONS
  Overweight/obese youth with 1-h glucose ≥155 mg/dL during the oral glucose tolerance test have a significantly lower β-cell function relative to insulin sensitivity even within the normal glucose tolerance range. Such youth may be at higher risk of future diabetes.
authors.affiliation: Division of Weight Management and Wellness, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA 15224, USA.
authors.forename: Hala
authors.initials: H
authors.lastname: Tfayli
authors.forename: So Jung
authors.initials: SJ
authors.lastname: Lee
authors.forename: Fida
authors.initials: F
authors.lastname: Bacha
authors.forename: Silva
authors.initials: S
authors.lastname: Arslanian
mesh_terms: D050153:Abdominal Fat / Q000378:metabolism; D015502:Absorptiometry, Photon; D000293:Adolescent; D001786:Blood Glucose / Q000032:analysis / Q000378:metabolism*; D001823:Body Composition; D002648:Child; D005260:Female; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D008297:Male; D050177:Overweight / Q000378:metabolism*; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D001786:Blood Glucose