Summary: In a case control study, age-related differences were compared between youth and adults with impaired glucose tolerance (IGT) or recently diagnosed diabetes. Youth had lower insulin sensitivity, hyperresponsive β-cells and reduced insulin clearance compared with adults.
Comment: This is one of two studies presenting detailed comparisons of glucose metabolism, insulin sensitivity and insulin secretion at baseline in adolescent versus adult cohorts using hyperglycemic clamps and oral glucose tolerance tests1.
Adolescents with IGT and T2DM differed significantly in their physiological parameters from adults. Specifically, insulin sensitivity was 46% lower in youth than in adults, and youth had higher fasting and stimulated levels of C-peptide than the adults. All beta-cell responses were significantly greater in youth. Interestingly, hepatic insulin clearance was reduced in youth. These results suggest a different pathophysiology in adolescents and adults with abnormal glucose tolerance, and support the notion that puberty augments insulin resistance. In light of the evidence that sustained demand on the β-cell may be an important predictor of progression of β-cell dysfunction, it is logical to assume that this hypersecretion is a critical contributor to the unique pathophysiology of youth-onset T2DM.2
References: 1. Consortium R. Metabolic Contrasts Between Youth and Adults With Impaired Glucose Tolerance or Recently Diagnosed Type 2 Diabetes: I. Observations Using the Hyperglycemic Clamp. Diabetes care. 2018; 41(8): 1696706.
2. Zeitler, P. World J Pediatr (2019). https://doi.org/10.1007/s12519-019-00247-1