2446-P: Markers of Glucose–Insulin Homeostasis across Puberty: The Health Start Study

Introduction and Objective: Little is known about the impact of the transient impact of physiological insulin resistance on insulin secretion dynamics during puberty in healthy youth. We examined measures of glycemia and insulin dynamics across puberty in healthy youth. Methods: A total of 337 youth ages 9-15 years (Tanner stages I through 4/5) participating in the Colorado Healthy Start Study completed a 3-hour oral glucose tolerance test (OGTT) with multiple measurements of glucose and C-peptide, as well as Tanner stage and body mass index (BMI) assessments. We modeled insulin secretion rates (ISR), incremental areas under the curve (iAUC) for C-peptide and glucose, and C-peptide clearance. Additional markers of insulin sensitivity included HOMA-IR, QUICKI, 1/insulin. Linear and ordinal logistic regressions were used to test for associations between Tanner stage and glucose-insulin outcomes, before and after adjustment for age and sex. Results: After adjustment, higher Tanner stage was associated with lower insulin sensitivity (HOMA-IR, QUICKI, 1/insulin), lower insulin clearance, higher insulin secretion rate, and higher iAUC for C-peptide (Table). There were no significant differences in fasting and 2-h glucose, glucose iAUC, or HbA1c across Tanner Stages. Conclusion: Puberty is associated with significant changes in insulin dynamics but does not appear to affect glycemia in healthy adolescents. Disclosure J. Giles: None. C.C. Cohen: None. D. Glueck: None. E.K. Englund: None. D. Dabelea: None. Funding National Institute of Diabetes and Digestive and Kidney Diseases (5R01DK133235-03)