A Higher Amount of Nutritional Intake as a Possible Cause of Hyperglycemia in Extremely Premature Infants in Parenteral and Enteral Nutrition at the Tertiary Neonatal Intensive Care Unit

Background: This study aimed to find an association between infants who had hyperglycemia and those who did not, those treated with insulin or not and several prenatal and postnatal variables or the suboptimal prescription of parenteral nutrition. Methods: We conducted a retrospective study, which included extremely premature infants (<28 weeks of gestation) admitted to the tertiary NICU, University Medical Centre Ljubljana, between 1 January 2021 and 31 December 2021. Blood glucose measurements, insulin treatment, general characteristics, nutritional data and complications of prematurity were obtained retrospectively from hospital data. RESULTS: There were 21 infants included in the study who did not receive insulin and 17 who were treated with insulin. Infants receiving insulin were younger and lighter compared to the non-insulin treatment group (mean gestational age 178 vs. 188 days; median birth weight 680 g vs. 990 g). The younger insulin group of infants received the same daily number of total macronutrients per kg per day compared to the older non-insulin group, i.e., glucose, lipids and amino acids, as recommended for the gestational age and birth weight. After adjusting for gestational age, no significant association with complications of prematurity was found. Conclusions: The postulated explanation (with the prescription of a higher amount of macronutrients during the first seven days) for hyperglycemia and treatment with insulin in the less mature and lighter infants cannot be supported by the data given.