Early Hyperglycemia Is Associated with Increased Incidence of Severe Retinopathy of Prematurity in Extremely Low Birth Weight Infants

Abstract

Objective Preterm infants have a higher rate of hypoglycemia and hyperglycemia, both of which have been associated with increased neonatal morbidities. The aim of this study was to evaluate the incidence of abnormal glucose homeostasis during the first 72 hours of life and study its association with major morbidities in infants admitted to our neonatal intensive care unit (NICU). Study Design This was a retrospective single-center study. We extracted demographic, maternal, and patient information and blood glucose levels for the first 72 hours of life for all infants with birth weight ≤1,000 g admitted to the NICU from January 2017 to December 2019. Continuous data were presented as mean ± standard deviation or as median with interquartile range. Categorical data were presented as frequency and percentage. Student's t-tests and Mann–Whitney U test were used to analyze continuous data and chi-squared test or Fisher's exact test were used to analyze categorical data. Logistic regression analysis was performed to study the relation between hyperglycemia and various morbidities after controlling for gestational age (GA). Statistical significance was set at p < 0.05. Results Of the 235 infants included in the study, 49% were hypoglycemic at admission to the NICU. Infants that were small for GA and those with history of maternal β-blocker use had a higher incidence of hypoglycemia. Hypoglycemia at admission was not associated with increased mortality or any major morbidities. Seventy-three percent infants who were hypoglycemic or euglycemic at birth developed iatrogenic hyperglycemia during the first 72 hours of life. The incidence of retinopathy of prematurity (ROP) and severe ROP was higher in infants with hyperglycemia on univariate analysis. However, on multivariate analysis, after adjusting for GA, no difference was noted in the incidence of ROP between the two groups. Multivariate analysis could not be performed for severe ROP due to inadequate sample size. Conclusion Hyperglycemia in the initial 3 days of life is associated with an increased incidence of severe ROP in preterm infants. Neonatologists should aim to maintain euglycemia in these infants to decrease the risk of adverse outcomes. Key Points