TUESDAY, June 25 (HealthDay News) -- Children with attention-deficit hyperactivity disorder should be steered away from contact sports such as football or basketball because these kids may be at greater risk of long-lasting head injury than their peers, a new study recommends.

Scientists found that children with ADHD -- who are already prone to risk-taking behaviors -- were much more likely than kids without the disorder to suffer a moderate disability after sustaining a mild traumatic brain injury from events such as car accidents, falls and injuries from high-impact sports.

"This was a phenomenon that I had noticed in my own practice -- some children with ADHD didn't recover as well following a traumatic brain injury," said senior study author Dr. Stephanie Greene, an assistant professor of neurological surgery at Children's Hospital of Pittsburgh. Some of the symptoms of traumatic brain injury are also symptoms of ADHD -- disinhibited behavior and impaired memory, she noted. "The effects of the [traumatic brain injury] may be additive to those of ADHD," she explained.


Encouraging activities in which the chances of brain injury are lower -- for example, swimming or track instead of football or basketball -- is a way in which parents can provide an outlet for energy while protecting their child's brain, she added.

The study is published online June 25 in the Journal of Neurosurgery: Pediatrics.

About 8 percent of American children have ADHD, a neurological disorder characterized by problems focusing, being overactive and exhibiting poor impulse control, according to the U.S. Centers for Disease Control and Prevention. Traumatic brain injury results in more than 7,000 deaths, 60,000 hospitalizations and 600,000 emergency room visits annually in the United States, according to the study. Prior research has linked several aspects of ADHD and traumatic brain injury.

In the new study, Greene and her colleagues reviewed medical charts of all patients at Children's Hospital of Pittsburgh who had ADHD and were diagnosed with a mild traumatic brain injury between 2003 and 2010. Forty-eight of these children were compared with a control group of 45 children without ADHD who had also sustained a mild traumatic brain injury.

The researchers found that 25 percent of the ADHD group suffered a moderate disability, and 56 percent had completely recovered after a nearly six-month follow-up period. In contrast, among the patients without ADHD, only 2 percent suffered a moderate disability and 84 percent had completely recovered after a much shorter follow-up of seven weeks. Moderate disability was defined as needing supervision or help for physical or behavioral problems, or having residual problems with learning or functioning.

Dr. Andrew Adesman, chief of developmental and behavioral pediatrics at Steven and Alexandra Cohen Children's Medical Center of New York in New Hyde Park, praised the study's design and said the authors excelled at explaining the possible implications of the findings.

"As someone who specializes in the evaluation and care of children with ADHD, I know they are at increased risk of injury," he said. "I think this study is suggesting that if they do experience a significant head injury, they may have greater long-term problems from that. Why that's true is hard to know."

The study made several recommendations stemming from the results, including that doctors should counsel families of children with ADHD about expected outcomes after a head injury; that more intensive treatment and rehabilitation for these patients be initiated; and that parents perhaps discourage children with ADHD from sports or hobbies that carry higher risks of sustaining a traumatic brain injury.

"Part of the problem with children with ADHD is that they often have poor impulse control, which means that they are at higher risk of sustaining a [traumatic brain injury] by engaging in risk-taking behaviors in daily life, separate from sports," Greene said. "When risky sports are added to the already elevated risk of [traumatic brain injury], the chances of a child sustaining a [traumatic brain injury] with potentially lingering effects become unacceptably high."

But Adesman said the findings need to be replicated before he would agree with curtailing contact sports for children with ADHD.

"I would not steer all kids with ADHD away from contact sports based on single study," he said. "Certainly we know that kids can experience accidents thru a variety of means . . . sports accidents made up a very small percent of accidents" in this study.

More information

The U.S. Centers for Disease Control and Prevention has more information about traumatic brain injury.