Racial Differences in Adiponectin in Youth

Relationship to visceral fat and insulin sensitivityv

  1. Silva A. Arslanian, MD
  1. From the Division of Pediatric Endocrinology, Metabolism and Diabetes Mellitus, Weight Management and Wellness Center, Children’s Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
  1. Address correspondence and reprint requests to Silva A. Arslanian, MD, Children’s Hospital of Pittsburgh, 3705 Fifth Avenue at DeSoto St., Pittsburgh, PA 15213. E-mail: silva.arslanian{at}chp.edu

Abstract

OBJECTIVE—The purpose of this study was to investigate 1) whether adiponectin is associated with insulin sensitivity independent of visceral adipose tissue in African-American and Caucasian youth and 2) whether adiponectin is associated with racial differences in insulin sensitivity.

RESEARCH DESIGN AND METHODS—Total body fat was measured by dual-energy X-ray absorptiometry and abdominal adipose tissue with computed tomography. Insulin sensitivity was measured by a 3-h hyperinsulinemic-euglycemic clamp.

RESULTS—Adiponectin was inversely associated (P < 0.01) with visceral adipose tissue, fasting insulin, and proinsulin and was positively related (P < 0.01) to insulin sensitivity after controlling for Tanner stage and sex independent of race. Stepwise multiple regression revealed that adiponectin was a strong independent predictor of insulin sensitivity, explaining 27% of the variance in insulin sensitivity. When subjects were categorized into tertiles of visceral adipose tissue and further low (≤50th) and high (>50th) adiponectin groups, insulin sensitivity was significantly different across the visceral adipose tissue groups (main effect, P < 0.01) in both races. However, within each visceral adipose tissue group, subjects with high adiponectin had higher insulin sensitivity (main effect, P < 0.05) than subjects with low adiponectin, independent of race. Racial differences in insulin sensitivity remained significant (P < 0.01) after controlling for leptin and visceral adipose tissue but not (P > 0.05) after additional adjustment for adiponectin.

CONCLUSIONS—Adiponectin is associated with insulin sensitivity independent of visceral adipose tissue in both African-American and Caucasian youth. Low adiponectin in African-American youth may be a biological marker that predisposes them to a greater risk of insulin resistance.

  • Received May 24, 2005.
  • Accepted September 17, 2005.
| Table of Contents