Insulin resistance prior to term age in very low birthweight infants: a prospective study

Abstract

ObjectiveTo explore the glucose-related hormone profile of very low birthweight (VLBW) infants and assess the association between neonatal hyperglycaemia and insulin resistance during the admission period.DesignA prospective observational study—the Very Low Birth Weight Infants, Glucose and Hormonal Profiles over Time study.SettingA tertiary neonatal intensive care unit and four neonatal units in county hospitals in Sweden.Patients48 infants born <1500 g (VLBW) during 2016–2019.Outcome measuresPlasma concentrations of glucose-related hormones and proteins (C-peptide, insulin, ghrelin, glucagon-like peptide 1 (GLP-1), glucagon, leptin, resistin and proinsulin), insulin:C-peptide and proinsulin:insulin ratios, Homoeostatic Model Assessment 2 (HOMA2) and Quantitative Insulin Sensitivity Check (QUICKI) indices, measured on day of life (DOL) 7 and at postmenstrual age 36 weeks.ResultsLower gestational age was significantly associated with higher glucose, C-peptide, insulin, proinsulin, leptin, ghrelin, resistin and GLP-1 concentrations, increased HOMA2 index, and decreased QUICKI index and proinsulin:insulin ratio. Hyperglycaemic infants had significantly higher glucose, C-peptide, insulin, leptin and proinsulin concentrations, and lower QUICKI index, than normoglycaemic infants. Higher glucose and proinsulin concentrations and insulin:C-peptide ratio, and lower QUICKI index on DOL 7 were significantly associated with longer duration of hyperglycaemia during the admission period.ConclusionsVLBW infants seem to have a hormone profile consistent with insulin resistance. Lower gestational age and hyperglycaemia are associated with higher concentrations of insulin resistance markers.