Persistent glucose production and greater peripheral sensitivity to insulin in the neonate vs. the adult

Abstract

Insulin resistance has been reported to partially explain the clinical appearance of neonatal hyperglycemia. To determine the relative resistance to insulin of glucose production vs. glucose utilization, the euglycemic hyperinsulinemic clamp technique was employed for the first time in the human neonate and was combined with stable isotopic determination of glucose production and glucose utilization. The basal rates of glucose production and glucose utilization were determined, after which each neonate was clamped at his or her own euglycemic glucose concentration while receiving regular human insulin at one rate of 0.2, 0.5, 1.0, 2.0, or 4.0 mU. kg-1.min-1. Persistent glucose production (> or = 1 mg.kg-1.min-1) during the clamp was recorded for all groups. A significant increase in the glucose infusion rate (P < 0.001) and in percent glucose utilization (P < 0.01) occurred in the 2.0 and 4.0 mU.kg-1.min-1 insulin groups. Metabolic clearance rate of insulin was significantly greater in the neonate compared with the adult at the 2.0 mU.kg-1.min-1 insulin infusion rate (P = 0.036). Our results indicate that, in contrast to the adult, the neonate has persistent glucose production (P = 0.001) and greater peripheral sensitivity to insulin (P = 0.015).

Intravenous insulin decreases protein breakdown in infants on extracorporeal membrane oxygenation

“…The data presented here are consistent with those reported in previous studies 22,24 and suggest that the experimental use of insulin infusions may be performed safely and effectively in neonates. Given the absence of nutritional methods to reduce protein breakdown, insulin may ultimately have broad applicability to the metabolic support of critically ill infants.…”

Low Birth Weight, a Risk Factor for Cardiovascular Diseases in Later Life, Is Already Associated With Elevated Fetal Glycosylated Hemoglobin at Birth

“…11,12,20 It is a limitation of the study methodology that insulin sensitivity was not measured directly; however, standard methods have not been validated in newborns, because most methods are highly invasive and thus not viable in large cohorts of healthy newborns. 21 A single measurement of glucose and insulin in cord blood gives little information because it reflects acute metabolic modifications induced by parturition. Decreased blood glucose concentrations in smallfor-date babies at birth reflect the reduced ability to cope with stress during delivery.…”

Insulin kinetics and the Neonatal Intensive Care Insulin–Nutrition–Glucose (NICING) model

“…Saturation of insulin mediated glucose uptake in adults is modulated with a Michaelis-Menten function, characterised by the parameter . For neonates no saturation has been observed [42], so this value is = 0.…”