Compensatory responses to insulin resistance in obese African-American and Latina girls

Pediatr Obes. 2013 Dec;8(6):e68-73. doi: 10.1111/j.2047-6310.2013.00184.x. Epub 2013 Jul 2.

Abstract

Purpose: Insulin responses to oral and intravenous glucose markedly differ by ethnicity. This study examined whether ethnic differences in pancreatic insulin secretion, hepatic insulin extraction and clearance explain these disparate findings in 35 obese African-American and 41 Latina girls (Tanner Stages: IV-V; ages: 14-18; body mass index percentile: 85.9-99.8%).

Methods: Pancreatic insulin secretion, hepatic insulin extraction and clearance were estimated by C-peptide and insulin modeling during an oral glucose tolerance test. Insulin sensitivity (SI), acute insulin response to glucose (AIRG ) and disposition index were derived from a frequently sampled intravenous glucose tolerance test.

Results: Compared to Latinas, obese African-American adolescents had lower pancreatic insulin secretion (21.3%; P < 0.01), glucose incremental area under the curve (IAUC) (41.7%, P = 0.02), C-peptide IAUC (25.1%, P < 0.01) and SI (33.7%; P < 0.01). There were no ethnic differences in hepatic insulin extraction and clearance (P's > 0.05).

Conclusions: Compensatory mechanisms to insulin resistance do not appear to explain the ethnic differences in insulin responses to oral and intravenous glucose in obese African-American and Latina girls.

Trial registration: ClinicalTrials.gov NCT00697580.

Keywords: African-American; Latina; hepatic insulin extraction; pancreatic insulin secretion.

Publication types

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

MeSH terms

  • Adolescent
  • Area Under Curve
  • Black or African American / statistics & numerical data*
  • Blood Glucose / metabolism*
  • Body Composition
  • Body Mass Index
  • C-Peptide / metabolism*
  • Female
  • Glucose Tolerance Test
  • Hispanic or Latino / statistics & numerical data*
  • Humans
  • Insulin / metabolism*
  • Insulin Resistance / ethnology*
  • Insulin Secretion
  • Insulin-Secreting Cells / metabolism
  • Obesity / ethnology
  • Obesity / metabolism*
  • United States / epidemiology

Substances

  • Blood Glucose
  • C-Peptide
  • Insulin

Associated data

  • ClinicalTrials.gov/NCT00697580