Longitudinal changes in insulin sensitivity, insulin secretion, and beta-cell function during puberty

J Pediatr. 2006 Jan;148(1):16-22. doi: 10.1016/j.jpeds.2005.08.059.

Abstract

Objective: To determine longitudinal changes in insulin sensitivity (SI), insulin secretion, and beta-cell function during puberty in white and black youth.

Study design: The tolbutamide-modified frequently sampled intravenous glucose tolerance test and minimal modeling were used to measure SI, the acute insulin response to glucose (AIRg), and beta-cell function (disposition index, DI) in white (n = 46) and black (n = 46) children (mean [+/-SD] age at baseline = 10.2 +/- 1.7 years). Growth curve models (including 272 observations) with SI, AIRg, and DI regressed on Tanner stage were run after adjusting for covariates.

Results: After adjusting for covariates, growth curve models revealed that SI decreased and subsequently recovered by the end of puberty in whites and blacks (both p < .05), AIRg decreased linearly across Tanner stages in both races (both p < .001), and DI decreased across puberty in blacks (p = .001) but not in whites (p = .2).

Conclusions: White and black youth exhibited transient insulin resistance and diminished AIRg during puberty. The progressive decline in DI among blacks versus whites may reflect a unique effect of puberty on beta-cell compensation in blacks. Future studies are needed to identify whether this difference contributes to the increased risk of type II diabetes in young blacks.

Publication types

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

MeSH terms

  • African Americans
  • Blood Glucose / metabolism
  • Body Weights and Measures
  • Chi-Square Distribution
  • Child
  • Child, Preschool
  • Energy Metabolism / physiology
  • European Continental Ancestry Group
  • Female
  • Glucose Tolerance Test
  • Humans
  • Insulin / metabolism*
  • Insulin Resistance / physiology*
  • Insulin Secretion
  • Insulin-Secreting Cells / metabolism*
  • Insulin-Secreting Cells / physiology
  • Longitudinal Studies
  • Male
  • Puberty / ethnology
  • Puberty / physiology*
  • Regression Analysis

Substances

  • Blood Glucose
  • Insulin