Tight glycemic control with insulin may not benefit hyperglycemic preterm infants

Insulin may not be a safe or more effective treatment for premature infants with hyperglycemia, according to a study published in the journal Pediatrics.

Researchers from University of Auckland in New Zealand analyzed the growth rates of 88 infants with hyperglycemia who were born earlier than 30 weeks' gestation or at less than 1,500 grams.

The infants were randomly assigned to either a “tight” group treated for tight glycemic control with insulin or a control group using the standard and more restrictive guidelines for starting insulin.

Researchers found that at 36 weeks' postmenstrual age, the infants in the tight group had a lesser lower leg growth rate compared to infants in the control group. They also had greater head circumference growth and greater weight gain compared to control infants.

However, tight group infants had a greater incidence of hypoglycemia than the control infants. There were no significant differences in nutritional intake, mortality or morbidity.

Hyperglycemia in infants is associated with increased mortality, a higher incidence of retinopathy or prematurity and intraventricular hemorrhage.

Severe or prolonged hypoglycemia may result in long-term neurologic damage, according to UC San Francisco Children's Hospital.

“Tight glycemic control with insulin in hyperglycemic preterm infants increases weight gain and head growth, but at the expense of reduced linear growth and increased risk of hypoglycemia,” wrote the authors of the study.

“The balance of risks and benefits of insulin treatment in hyperglycemic preterm neonates remains uncertain,” they wrote.

Hyperglycemia is a common problem in very preterm infants, according to the National Institutes of Health. Among extremely low birth weight infants, the incidence of neonatal hyperglycemia is between 45 percent and 80 percent.

Treating hyperglycemic premature infants with insulin is common but little evidence exists to support this practice, according to clinicaladvisor.com.

Clinicaladvisor.com reports that the American College of Physicians advises against tight glycemic control in adult ICU patients due to hypoglycemia concerns.

Sources: Pediatrics, clinicaladvisor.com, National Institutes of Health, UCSF Children's Hospital