Children who have severe traumatic brain injuries early in life may have impaired cognitive development and long-term intellectual ability as they get older, according to two small studies published Monday in the journal Pediatrics.

The first study compared the social, intellectual, and behavioral functions of 53 children who had experienced a traumatic brain injury before the age of three, most of which were the result of falls, with 27 children of the same age who had never sustained a TBI.

The authors write that while a severe TBI was associated with lowered intellectual function, the socioeconomic status of the child's family may be a more powerful predictor of the child's intellectual development. They cannot fully explain why, but they suggest lower socioeconomic status, high parental stress and low parental involvement has an effect on a child's recovery.



The study also found that mild, less traumatic injuries, similar to those commonly sustained from short falls, had no negative effect on any of the child's functions.

The second prospective study, which was conducted at the same children's hospital in Australia, looked at 40 children who had sustained a TBI at some point between the ages of two and seven.

More of the injuries were sustained from motor vehicle or pedestrian accidents than were in the first study and therefore the children had more severe TBIs in this study. The researchers examined the children immediately after the injury, and then again 12 months, 30 months, and ten years later.

Children in this study who suffered a mild traumatic injury recovered well and didn't face a dramatic deficit in their intellectual abilities, similar to what was seen in the first study. Researchers also found children with severe TBI had problems with their intellectual, behavioral, and social development. More specifically, children with severe traumatic brain injuries seemed to lag behind their peers in intellectual development for upwards of three years after their injury.

"Some of the children with severe TBI did well" after their injury, says Dr. Harvey S. Levin, with the Department of Physical Medicine and Rehabilitation at Baylor College of Medicine, who wrote accompanying commentary and was not involved in the two studies.

"There is intellectual growth with age so it's not like these children don't continue to show intellectual development, but there is a lag."

Levin says that the two studies challenge long-held beliefs within the medical community that young children are not as vulnerable to the negative effects of traumatic brain injury. Rather, factors like the severity of the TBI and the amount of trauma associated with the injury hold more weight in determine how much of a deficit a child may experience.

Children are at high risk for traumatic brain injury particularly because of their propensity to fall. Babies and toddlers are still developing their sense of balance, which is why they often take a tumble. Most falls don't cause anything nearly as serious as a traumatic brain injury, but being around stairs or furniture with hard edges, or walking up an incline, could increase the chances of it happening.