One-hour plasma glucose concentration during the OGTT: what does it tell about β-cell function relative to insulin sensitivity in overweight/obese children?

Pediatr Diabetes. 2011 Sep;12(6):572-9. doi: 10.1111/j.1399-5448.2011.00745.x. Epub 2011 Apr 6.


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.

Research design and 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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Abdominal Fat / metabolism
  • Absorptiometry, Photon
  • Adolescent
  • Blood Glucose / analysis
  • Blood Glucose / metabolism*
  • Body Composition
  • Child
  • Female
  • Glucose Clamp Technique
  • Glucose Tolerance Test
  • Humans
  • Insulin Resistance / physiology*
  • Insulin-Secreting Cells / metabolism*
  • Male
  • Overweight / metabolism*
  • Tomography, X-Ray Computed
  • Young Adult


  • Blood Glucose