The poor growth seen in children born with complex heart defects may result from factors beyond deficient nutrition, and a new study suggests that abnormalities in overall growth regulation could play a role.

"When compared with their healthy peers, children with congenital heart disease have impaired growth, as measured in weight, length, and head circumference," said the study's senior author Meryl S. Cohen, MD, a pediatric cardiologist in the Cardiac Center at The Children's Hospital of Philadelphia. "We investigated patterns of poor growth in these children, as a starting point in guiding us toward more effective treatments."

The study appeared online recently in Pediatrics.

The researchers performed a retrospective analysis of medical records of 856 children with congenital heart disease (CHD), compared to 7,654 matched control subjects. All of the children were measured up to age 3, and all were drawn from Children's Hospital's healthcare network. Deficits in weight, length and head circumference occurred within weeks of birth.

Within weeks of birth, the children with CHD had significant deficits in weight, length and head circumference, compared to matched controls without CHD. The largest differences in weight occurred at 4 months of age. Among the 856 children with CHD, the 248 who required surgical repair were much more likely to be below the 3rd percentile in weight, length and head circumference during early infancy, and their growth by age 3 did not catch up with that of their healthy peers.

In the 608 children with CHD who did not require surgery, growth differences were not as pronounced, but even their growth patterns lagged behind those of healthy controls. Findings suggest impaired growth in children with CHD at least partly affected by factors unrelated to nutrition.

Researchers had previously known that children with CHD are at increased risk for poor growth, but this analysis provides a fuller picture of the problem.