Newborns depend on glucose, also known as blood sugar, for energy. If the amount of glucose supplied by the blood drops significantly, the brain is one of the first organs affected.
Neonatal hypoglycemia refers to low blood sugar levels in infants. While it is well-documented that prolonged hypoglycemia causes brain damage and poor long-term neurodevelopment, a new study led by Texas Children’s neonatologist Dr. Jeffrey Kaiser found that a brief drop in blood sugar at birth, commonly referred to as transient hypoglycemia, may be linked to lower literacy and math achievement test scores in fourth grade.
Kaiser and his research colleagues from Baylor College of Medicine and the University of Arkansas for Medical Sciences published their compelling findings in the journal JAMA Pediatrics.
Using data from infants born at the University of Arkansas for Medical Sciences Hospital in 1998 – where all newborns have their sugar levels screened during the first three hours after birth – the team sought to determine the effect of low blood sugar level on academic achievement in fourth grade.
With the availability of the universal glucose screening data in Arkansas from more than 30,000 infants, Kaiser and his team collaborated with the Arkansas Department of Education and Arkansas Department of Health to match data from 1,395 infants born in 1998 with their 2008 achievement test scores when the children were 10 years old.
The study included infants with normal glucose levels at birth and those with the transiently low levels. Newborns with persistently low glucose levels were excluded from the study because they are known to have worse neurodevelopment.
After controlling for gestational age, race, gender, socioeconomic status and maternal education, the team found babies with normal glucose levels were about 20 percent more proficient than those with transiently low glucose levels. Kaiser said this finding is important because lower fourth-grade achievement test scores are associated with lower high school graduation rates, less college attendance and, ultimately, less long-term economic success.
While this study suggests transient hypoglycemia could harm infant’s brains, Kaiser cautions these are preliminary findings and more research is needed to validate these findings in other populations before universal newborn glucose screening should be adopted.
“This is just one piece of the puzzle,” Kaiser said. “Now that we have shown some evidence of the impact of early transient newborn hypoglycemia, and if corroborated by other researchers, maybe we will screen for it and treat it to prevent these cognitive defects.”
Currently, Texas Children’s Newborn Center follows the American Academy of Pediatrics’ current guidelines which restricts newborn glucose screening to infants considered high risk for hypoglycemia. These include babies born to diabetic mothers, premature infants, and infants who are small or large for gestational age.
To learn more about Kaiser’s study in the journal JAMA Pediatrics, click here.