Body trunk fat and insulin resistance in post-pubertal obese adolescents
Keywords:
Adolescent, Body composition, Abdominal fat, Insulin resistance, ObesityAbstract
CONTEXT AND OBJECTIVE: Insulin resistance is a metabolic disorder commonly associated with excess body fat accumulation that may increase chronic disease risk. The present study was undertaken to evaluate the relationship between body composition and insulin resistance among obese adolescents. DESIGN AND SETTING: Cross-sectional study, at the Adolescence Center, Pediatric Department, Universidade Federal de São Paulo. METHODS: Body composition was assessed using dual-energy X-ray absorptiometry. Dietary intake was evaluated using a three-day dietary record. The biochemical evaluation comprised glucose, insulin, serum lipid, leptin and ghrelin measurements. Insulin resistance was calculated by means of the homeostasis model assessment of insulin resistance (HOMA-IR). RESULTS: Forty-nine post-pubertal obese adolescents participated in the study: 12 boys and 37 girls of mean age 16.6 (1.4) years and mean body mass index (BMI) of 35.0 (3.9) kg/m2. The mean glucose, insulin and HOMA values were 90.3 (6.4) mg/dl, 16.6 (8.1) µIU/ml and 3.7 (1.9), respectively. Hyperinsulinemia and insulin resistance were observed in 40.2% and 57.1% of the subjects, respectively. Adolescents with insulin resistance had higher BMI and body trunk fat. There was a trend towards higher leptin concentration in obese individuals with insulin resistance. Insulin resistance was positively correlated with body trunk fat, BMI, body fat mass (kg), leptin and body fat percentage. Furthermore, there was a negative correlation between HOMA-IR and lean body mass. The body composition predicted 30% of the HOMA-IR levels, according to linear regression models. CONCLUSION: Body trunk fat was signifi cantly associated with insulin resistance, demonstrating the clinical importance of abdominal obesity during adolescence.
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Roemmich JN, Clark PA, Lusk M, et al. Pubertal alterations in growth and body composition. VI. Pubertal insulin resistance: relation to adiposity, body fat distribution and hormone release. Int J Obes Relat Metab Disord. 2002;26(5):701-9.
Tershakovec AM, Kuppler KM, Zemel BS, et al. Body composi- tion and metabolic factors in obese children and adolescents. Int J Obes Relat Metab Disord. 2003;27(1):19-24.
Keskin M, Kurtoglu S, Kendirci M, Atabek E, Yazici C. Ho- meostasis model assessment is more reliable than the fasting glucose/insulin ratio and quantitative insulin sensitivity check index for assessing insulin resistance among obese children and adolescents. Pediatrics. 2005;115(4):e500-3.
Sinaiko AR, Jacobs DR Jr, Steinberger J, et al. Insulin resistance syndrome in childhood: associations of the euglycemic insulin clamp and fasting insulin with fatness and other risk factors. J Pediatr. 2001;139(5):700-7.
Ali AT, Crowther NJ. Body fat distribution and insulin resis- tance. S Afr Med J. 2005;95(11):878-80.
Wang Y, Monteiro C, Popkin BM. Trends of obesity and under- weight in older children and adolescents in the United States, Brazil, China, and Russia. Am J Clin Nutr. 2002;75(6):971-7.
Cintra Ide P, Passos MA, Fisberg M, Machado HC. Evolução em duas séries históricas do índice de massa corporal em adolescentes. [Evolution of body mass index in two historical series of adolescents]. J Pediatr (Rio J). 2007;83(2):157-62.
Slyper AH. Childhood obesity, adipose tissue distribution, and the pediatric practitioner. Pediatrics. 1998;102(1):e4.
Vendrell J, Broch M, Vilarrasa N, et al. Resistin, adiponectin, ghrelin, leptin, and proinflammatory cytokines: relationships in obesity. Obes Res. 2004;12(6):962-71.
Huang KC, Lin RC, Kormas N, et al. Plasma leptin is associated with insulin resistance independent of age, body mass index, fat mass, lipids, and pubertal development in nondiabetic adoles- cents. Int J Obes Relat Metab Disord. 2004;28(4):470-5.
Tanner JM. Growth at adolescence. Oxford: Blackwell; 1962.
Institute of Medicine. Dietary reference intakes for energy, carbo- hydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids (macronutrients). Washington: National Academies Press; 2002.
Centers for Disease Control and Prevention. National Center for Health Statistics. 2000 CDC Growth Charts: United States. Available from: htpp://www.cdc.gov/growthcharts. Accessed in 2008 (Jan 30).
Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. Report of the expert committee on the diagnosis and classification of diabetes mellitus. Diabetes Care. 2003;26(Suppl 1):S5-20.
Matthews DR, Hosker JP, Rudenski AS, Naylor BA, Treacher DF, Turner RC. Homeostasis model assessment: insulin resistance and beta-cell function from fasting plasma glucose and insulin concentrations in man. Diabetologia. 1985;28(7):412-9.
Freedman DS, Dietz WH, Srinivasan SR, Berenson GS. The relation of overweight to cardiovascular risk factors among children and adolescents: the Bogalusa Heart Study. Pediatrics. 1999;103(6 Pt 1):1175-82.
Yanovski JA, Yanovski SZ, Cutler GB Jr, Chrousos GP, Filmer KM. Differences in the hypothalamic-pituitary-adrenal axis of black girls and white girls. J Pediatr. 1996;129(1):130-5.
Weiss R, Dziura J, Burgert TS, et al. Obesity and the meta- bolic syndrome in children and adolescents. N Engl J Med. 2004;350(23):2362-74.
Spear BA. Adolescent growth and development. J Am Diet Assoc. 2002;102 (3 Suppl):S23-9.
Björntorp P. Metabolic implications of body fat distribution. Diabetes Care. 1991;14(12):1132-43.
Yildiz BO, Suchard MA, Wong ML, McCann SM, Licinio J. Alterations in the dynamics of circulating ghrelin, adiponec- tin, and leptin in human obesity. Proc Natl Acad Sci U S A. 2004;101(28):10434-9.
McAuley KA, Williams SM, Mann JI, et al. Diagnosing insulin resistance in the general population. Diabetes Care. 2001;24(3):460-4.
Tschöp M, Weyer C, Tataranni PA, Devanarayan V, Ravussin E, Heiman ML. Circulating ghrelin levels are decreased in human obesity. Diabetes. 2001;50(4):707-9.
Ikezaki A, Hosoda H, Ito K, et al. Fasting plasma ghrelin levels are negatively correlated with insulin resistance and PAI-1, but not with leptin, in obese children and adolescents. Diabetes. 2002;51(12)3408-11.
Ueno H, Yamaguchi H, Kangawa K, Nakazato M. Ghrelin: a gastric peptide that regulates food intake and energy homeo- stasis. Regul Pept. 2005;126(1-2):11-9.
