Neonatal hypoglycemia is common in newborns and treatment can help reduce the risk of brain injury from severe, prolonged, or recurrent hypoglycemia. A presentation at the 81st Virtual Science 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 the impact of rapid correction on brain injury.
In a study using rats, researchers found that hypoglycemia led to injury in the areas of the brain that control emotion, attention and learning, as well as cognitive function. In the adult rats, this led to problems with the areas related to visuospatial information processing and the ability to smell. In cases of acute hypoglycemia, the brain will initially use glucose and then switch to other substrates. When those substrates are depleted, there is energy failure that can lead to brain injury. Although administration of dextrose can lead to improved metabolites, some metabolites such as aspartate and glutamine do not recover readily after treatment. Another test in rhesus monkeys included monkeys with varying durations of hypoglycemia, including 6 hours and 10 hours. In this study, the researchers found that both cognitive and behavioral performance were unaffected in people with 6 hours of hypoglycemia. However, training problems were noted in 50% of the monkeys who spent 10 hours. No differences in memory or personality were noted in either group.
The New Zealand CHYLD study included 604 preterm and term at-risk children who received glucose monitoring for the first 7 days. The children received a neurodevelopmental assessment at the ages of 2 and 4.5 years. There was no association between neonatal hypoglycemia and neurosensory impairment in either assessment. However, infants with hypoglycaemia were found to have more executive dysfunction, impaired visual-motor integration, and a greater risk of severe and recurrent hypoglycaemia at the 4.5-year assessment.
Rao also discussed a study in rats comparing the use of different doses of dextrose, 10% vs. 50%, to terminate acute hypoglycemia. The researchers in this study found that using the 50% dextrose solution was associated with a higher risk of neuronal damage.
1. Rao R. Long-term results of neonatal hypoglycemia clinical lessons from the laboratory. American Diabetes Association Scientific Sessions 2021; June 28, 2021; virtual. Access until June 28, 2021.