March is National Cerebral Palsy Awareness Month. Designations like this are important as they provide an opportunity to bring this condition into the national discussion; to educate the public, review progress, and push for more research where needed.
We have made significant progress with education and research efforts for cerebral palsy. Scientific advances have allowed us to identify the impact of damage to the brain and network of nerves that can result in cerebral palsy and provided ways to reduce these risks. Another important area of study is the connection between neonatal hypoglycemia and cerebral palsy.
What is neonatal hypoglycemia?
Medical professionals generally define neonatal hypoglycemia as a blood glucose concentration less than 47 mg/dL — but it is important to realize this definition is evolving. This is because we know healthy infants experience fluctuations in blood glucose levels as they transition to extrauterine life. Unfortunately, we do not have a good understanding of a normal range of fluctuation because we rarely measure blood glucose concentrations in healthy infants unless other risk factors for hypoglycemia are present.
Thus, we do not yet have clear definitions for normal blood glucose levels.
Researchers have studied these levels in an attempt to define a normal range within the first few hours and days of life after birth and the potential impact of hypoglycemia on neurosensory impairments for decades. In the 1980s, researchers noted that infants who went with a blood glucose concentration less than 47mg/dL for five days or more had a three to five time increase in the risk of a neurodevelopmental impairment as they aged.
We are still learning the full impact of low blood glucose levels on neurological growth. In a recent example published in the Journal of the American Medical Association (JAMA), researchers found further evidence to support the belief that children exposed to neonatal hypoglycemia were at an increased risk of neurosensory impairment including cerebral palsy, blindness, and deafness. This study is significant because it focuses on outcomes at an earlier age: two years. Most research investigates the performance and neurosensory impairment resulting from neonatal hypoglycemia after the infants become older. This information is valuable because it can provide parents with evidence to support their concerns and potential need for future treatment connected to untreated neonatal hypoglycemia at an earlier point in the infant’s development.
What did the researchers find when examining children at two years of age after experiencing neonatal hypoglycemia?
Researchers compared 1197 infants who experienced neonatal hypoglycemia to normoglycemia infants and found those who experienced hypoglycemia were at an increased risk of neurosensory impairment. Researchers found 23% of the infants who experienced hypoglycemia suffered a neurosensory impairment. 18% of infants with normoglycemia reported similar impairments. Of those with severe hypoglycemia, 28% suffered neurosensory impairments.
The most important finding in these studies is the importance of treating severe, prolonged hypoglycemia. A failure to do so can have catastrophic outcomes including long-term neurodevelopmental disabilities, cerebral palsy, and death.
What types of treatments does the AAP recommend?
Again, more research is needed, but at this time initiation of breastfeeding within the first hour after birth, if possible, is beneficial as well as an initial glucose screening thirty minutes after the first feeding. The American Academy of Pediatrics (AAP) recommends glucose readings at or over 45 mg/dL prior to routine feedings. The AAP also encourages intervention if the blood glucose levels fall below 40 mg/dL in the infant’s first four hours after birth.
The AAP recommends increased feeding frequency as the primary source of intervention with breastfeeding as the first choice and infant formula as an alternative. Use of dextrose gel can also provide an effective alternative option for treatment. In some cases, admission to the neonatal intensive care until and use of intravenous dextrose is recommended.