What are the long-term outcomes of neonatal hypoglycemia?

Neonatal hypoglycemia is a common occurrence in newborns and treatment can help reduce the risk of brain injury due to severe, prolonged, or recurrent hypoglycemia. A presentation at the 81st virtual Scientific Sessions for the American Diabetes Association examined the long-term outcomes of neonatal hypoglycemia. Raghavendra Rao, MD, a professor of pediatrics and director of the division of neonatology at the University of Minnesota in Minneapolis, discussed whether newborn brains were more vulnerable than adult brains during hypoglycemia as well as well the impact of rapid correction on brain injury.

In a study that used rats, investigators found that hypoglycemia led to injury in the areas of the brain that govern emotion, attention and learning as well as cognitive function. In the adult rats, it led to problems with the areas that involve visuospatial information processing and the ability to smell. In cases of acute hypoglycemia, the brain will initially use glucose and then move onto other substrates. If those substrates are exhausted, there is energy failure which can lead to brain injury. Although dextrose administration can lead to improved metabolite levels, some metabolites such as aspartate and glutamine do not easily recover after treatment. Another test in rhesus monkeys included monkeys that had different durations of hypoglycemia including 6 hours and 10 hours. In this study, the investigators found that both cognitive and behavioral performance were unaffected in those with 6 hours of hypoglycemia. However, there were training difficulties noted in 50% of the monkeys who had experienced 10 hours. No memory or personality differences were noted in either group.

The CHYLD study from New Zealand involved 604 preterm and term at-risk infants who received glucose monitoring for the first 7 days. The children were given a neurodevelopmental assessment at age 2 and 4.5 years. There was no link between neonatal hypoglycemia and neurosensory impairment at either assessment. However, infants with hypoglycemia were found to have more executive dysfunction, impaired visual-motor integration, and greater risk of severe and recurrent hypoglycemia at the 4.5 year assessment.

Rao also discussed a study in rats that compared using different doses of dextrose, 10% versus 50%, to end acute hypoglycemia. The investigators in this study found that the use of the 50% dextrose solution was linked to a higher risk of neuronal injury.

Reference

1. Rao R. Long-term outcomes of neonatal hypoglycemia-clinical lessons from the lab. American Diabetes Association Scientific Sessions 2021; June 28, 2021; virtual. Accessed June 28, 2021.