Relation of leptin to insulin resistance syndrome in children.
OBJECTIVE
To examine the relation of leptin to insulin resistance, as measured by euglycemic insulin clamp, and insulin resistance syndrome factors in thin and heavy children.


METHODS
Anthropometrics, insulin, blood pressure, and leptin were measured in 342 11- to 14-year-old children (189 boys, 153 girls, 272 white, 70 black). Insulin sensitivity (M) was determined by milligrams glucose uptake per kilogram per minute and expressed as M/lean body mass (Mlbm). Children were divided by median BMI (boys = 20.5 kg/m(2); girls = 21.4 kg/m(2)) into below-median (thin) and above-median (heavy) groups. Correlation coefficients between log-leptin and components of insulin resistance syndrome were adjusted for Tanner stage, gender, and race.


RESULTS
BMI was related to leptin in boys (r = 0.70, p < 0.001) and girls (r = 0.75, p < 0.001). Leptin was higher in girls than boys (32.6 vs. 12.3 ng/mL, p = 0.0001). Leptin levels increased in girls and decreased in boys during puberty, paralleling the changes in body fat. Leptin was significantly correlated with insulin, Mlbm, triglycerides, and blood pressure in heavy children and only with insulin in thin children. After adjustment for body fat, the correlations remained significant for insulin and Mlbm in heavy children and with insulin in thin children.


CONCLUSIONS
Significant associations were found between leptin and insulin resistance in children, and these associations were attenuated by adjustment for adiposity. These findings at age 13 likely have long-term consequences in the development of the obesity-insulin resistance-related cardiovascular risk profile.
Steinberger
Julia
J
Department of Pediatrics, University of Minnesota Medical School, University of Minnesota School of Public Health, Minneapolis, Minnesota 55455, USA. stein055@unm.edu
Steffen
Lyn
L
Jacobs
David R
DR
Moran
Antoinette
A
Hong
Ching-Ping
CP
Sinaiko
Alan R
AR
D000293:Adolescent; D000375:Aging / Q000097:blood / Q000502:physiology*; D000886:Anthropometry; D001786:Blood Glucose / Q000032:analysis; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology; D002648:Child; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000209:etiology; D005260:Female; D015309:Glucose Clamp Technique; D006801:Humans; D020738:Leptin / Q000097:blood*; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood* / Q000209:etiology; D009765:Obesity / Q000097:blood* / Q000503:physiopathology; D011627:Puberty / Q000097:blood / Q000502:physiology; D012307:Risk Factors; D012727:Sex Characteristics
D001786:Blood Glucose; D020738:Leptin