I M Libman1, E Barinas-Mitchell, A Bartucci, R Robertson, S Arslanian. 1. Children's Hospital of Pittsburgh, and Department of Epidemiology, Graduate School of Public Health, Center for Exercise and Health-Fitness Research, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA. ingrid.libman@chp.edu
Abstract
OBJECTIVE: We examined the reproducibility of the oral glucose tolerance test (OGTT) in overweight children and evaluated distinguishing characteristics between those with concordant vs. discordant results. DESIGN: Sixty overweight youth (8-17 yr old) completed two OGTTs (interval between tests 1-25 d). Insulin sensitivity was assessed by the surrogate measures of fasting glucose to insulin ratio, whole-body insulin sensitivity index, and homeostasis model assessment of insulin resistance, and insulin secretion by the insulinogenic index with calculation of the glucose disposition index (GDI). RESULTS: Of the 10 subjects with impaired glucose tolerance (IGT) during the first OGTT only three (30%) had IGT during the second OGTT. The percent positive agreement between the first and second OGTT was low for both impaired fasting glucose and IGT (22.2 and 27.3%, respectively). Fasting blood glucose had higher reproducibility, compared with the 2-h glucose. Youth with discordant OGTTs, compared with those with concordant results, were more insulin resistant (glucose/insulin 2.7+/-1.4 vs. 4.1+/-1.8, P=0.006, whole-body insulin sensitivity index of 1.3+/-0.6 vs. 2.2+/-1.1, P=0.003, and homeostasis model assessment of insulin resistance 10.6+/-8.1 vs. 5.7+/-2.8, P=0.001), had a lower GDI (0.45+/-0.58 vs. 1.02+/-1.0, P=0.03), and had higher low-density lipoprotein cholesterol (117.7+/-36.6 vs. 89.9+/-20.1, P=0.0005) without differences in physical characteristics. CONCLUSIONS: Our results show poor reproducibility of the OGTT in obese youth, in particular for the 2-h plasma glucose. Obese youth who have discordant OGTT results are more insulin resistant with higher risk of developing type 2 diabetes mellitus, as evidenced by a lower GDI. The implications of this remain to be determined in clinical and research settings.
OBJECTIVE: We examined the reproducibility of the oral glucose tolerance test (OGTT) in overweight children and evaluated distinguishing characteristics between those with concordant vs. discordant results. DESIGN: Sixty overweight youth (8-17 yr old) completed two OGTTs (interval between tests 1-25 d). Insulin sensitivity was assessed by the surrogate measures of fasting glucose to insulin ratio, whole-body insulin sensitivity index, and homeostasis model assessment of insulin resistance, and insulin secretion by the insulinogenic index with calculation of the glucose disposition index (GDI). RESULTS: Of the 10 subjects with impaired glucose tolerance (IGT) during the first OGTT only three (30%) had IGT during the second OGTT. The percent positive agreement between the first and second OGTT was low for both impaired fasting glucose and IGT (22.2 and 27.3%, respectively). Fasting blood glucose had higher reproducibility, compared with the 2-h glucose. Youth with discordant OGTTs, compared with those with concordant results, were more insulin resistant (glucose/insulin 2.7+/-1.4 vs. 4.1+/-1.8, P=0.006, whole-body insulin sensitivity index of 1.3+/-0.6 vs. 2.2+/-1.1, P=0.003, and homeostasis model assessment of insulin resistance 10.6+/-8.1 vs. 5.7+/-2.8, P=0.001), had a lower GDI (0.45+/-0.58 vs. 1.02+/-1.0, P=0.03), and had higher low-density lipoprotein cholesterol (117.7+/-36.6 vs. 89.9+/-20.1, P=0.0005) without differences in physical characteristics. CONCLUSIONS: Our results show poor reproducibility of the OGTT in obese youth, in particular for the 2-h plasma glucose. Obese youth who have discordant OGTT results are more insulin resistant with higher risk of developing type 2 diabetes mellitus, as evidenced by a lower GDI. The implications of this remain to be determined in clinical and research settings.
Authors: George Alberti; Paul Zimmet; Jonathan Shaw; Zachary Bloomgarden; Francine Kaufman; Martin Silink Journal: Diabetes Care Date: 2004-07 Impact factor: 19.112
Authors: Ingrid M Libman; E Barinas-Mitchell; S Marcovina; F Bacha; T Hannon; H Tfayli; S J Lee; S Bansal; R Robertson; S Arslanian Journal: Pediatr Diabetes Date: 2010-09-07 Impact factor: 4.866
Authors: Christine L Chan; Kim McFann; Lindsey Newnes; Kristen J Nadeau; Philip S Zeitler; Megan Kelsey Journal: Pediatr Diabetes Date: 2014-03-17 Impact factor: 4.866
Authors: Silva Arslanian; Laure El Ghormli; Joon Young Kim; Fida Bacha; Christine Chan; Heba M Ismail; Lorraine E Levitt Katz; Lynne Levitsky; Jeanie B Tryggestad; Neil H White Journal: Diabetes Care Date: 2018-11-19 Impact factor: 19.112