Neonatal hypoglycemia slows development

Of all the neonatal morbidities that commonly plague moderately preterm-born babies, only hypoglycemia is associated with increased risk of developmental delays by the time the children reach preschool.

New research from the Netherlands has found that neonatal hypoglycemia (glucose values <1.7 mmol/L) in this population more than doubled the risk of delayed development.

Investigators sought to determine the effects of common neonatal health complications in moderately preterm-born children (ie, 32-35 weeks’ gestation) on their development by preschool age.

In a community-based study, the researchers looked at data on 832 children born moderately preterm in 2002 or 2003. They reviewed medical records for various factors including Apgar scores, asphyxia, tertiary neonatal intensive care unit admission, hospital transfer, circulatory insufficiency, hypoglycemia, septicemia, mechanical ventilation, continuous positive airway pressure, apneas, caffeine treatment, and hyperbilirubinemia.

They also assessed the children at 43 to 49 months for communication, fine motor, gross motor, problem solving, and personal-social functioning through parents’ answers to the 48-month Ages and Stages Questionnaire.

After adjusting for factors such as sex, small-for-gestational-age status, gestational age, and maternal education, the investigators found that in univariate analyses both hypoglycemia and asphyxia more than doubled the risk of developmental delay. In multivariate analyses, however, no other common neonatal morbidity, including respiratory insufficiency, circulatory insufficiency, and septicemia, was associated with developmental delay except hypoglycemia.

A documented glucose value below 1.7 mmol/L increased the risk of developmental delay from 9.1% to almost 20%.

Further, the researchers found that 8.1% of the infants in the study had at least 1 documented glucose value less than 1.7 mmol/L. The risk of developmental delay increased as glucose values decreased, suggesting an increased risk of brain injury at values below 1.7 mmol/L.

No consensus exists on a threshold level for hypoglycemia that will lead to brain injury, but the researchers believe that their findings underscore the need for pediatricians to make every effort to ensure that neonatal hypoglycemia does not occur.

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