Objectives: To assess insulin dynamics to oral glucose tolerance testing in o bese children, denoting individual contributions of insulin hypersecretion versu s resistance to racial and etiopathogenetic specificity. S...Objectives: To assess insulin dynamics to oral glucose tolerance testing in o bese children, denoting individual contributions of insulin hypersecretion versu s resistance to racial and etiopathogenetic specificity. Study design: We perfor med 3- hour oral glucose tolerance testing in 113 nondiabetic obese children (a ge 13.6 ± 3.1 years; 41 male, 78 female; 37 black, 41 white; 35 with central n ervous system [CNS] insult). The corrected insulin response (CIRgp; measuring β - cell secretion) and the composite insulin sensitivity index (CISI) were comp uted and log- transformed, and each was modeled in terms of the other, plus rac e/etiology, age, sex, body mass index z score, glucose tolerance, pubertal statu s, and geographic location. Results: A scatterplot of logCIRgp versus logCISI sh owed that racial and etiopathogenetic groups plotted in different areas. CISI (c ontrolled for CIRgp and other variables) was only 13% lower in blacks than in whites (P = .32). Conversely, CIRgp (controlled for CISI and other variables) wa s 49% higher in blacks (P = .028). CNS insult exhibited a 40% higher CIRgp ( P = .054) and 11% higher CISI (P = .42) than intact white subjects. Conclusion s: Insulin hypersecretion and resistance are distinct phenomena in childhood obe sity. Insulin hypersecretion ap- pears to be the more relevant insulin abnormal ity both in obese blacks and in CNS insult.展开更多
文摘Objectives: To assess insulin dynamics to oral glucose tolerance testing in o bese children, denoting individual contributions of insulin hypersecretion versu s resistance to racial and etiopathogenetic specificity. Study design: We perfor med 3- hour oral glucose tolerance testing in 113 nondiabetic obese children (a ge 13.6 ± 3.1 years; 41 male, 78 female; 37 black, 41 white; 35 with central n ervous system [CNS] insult). The corrected insulin response (CIRgp; measuring β - cell secretion) and the composite insulin sensitivity index (CISI) were comp uted and log- transformed, and each was modeled in terms of the other, plus rac e/etiology, age, sex, body mass index z score, glucose tolerance, pubertal statu s, and geographic location. Results: A scatterplot of logCIRgp versus logCISI sh owed that racial and etiopathogenetic groups plotted in different areas. CISI (c ontrolled for CIRgp and other variables) was only 13% lower in blacks than in whites (P = .32). Conversely, CIRgp (controlled for CISI and other variables) wa s 49% higher in blacks (P = .028). CNS insult exhibited a 40% higher CIRgp ( P = .054) and 11% higher CISI (P = .42) than intact white subjects. Conclusion s: Insulin hypersecretion and resistance are distinct phenomena in childhood obe sity. Insulin hypersecretion ap- pears to be the more relevant insulin abnormal ity both in obese blacks and in CNS insult.