By Lisa Rapaport

(Reuters Health) – Children, teens and young adults with attention deficit hyperactivity disorder (ADHD) may be more than four times more likely to sustain traumatic brain injuries than other youth, a Taiwanese study suggests.

Researchers examined national health insurance data on more than 72,000 youth with ADHD who ranged in age from 3 to 29 years, as well as a control group of similar young people without ADHD. Study participants were enrolled between 2001 and 2009 and tracked until the end of 2011.

Overall, almost 7,100 youth with ADHD, or 9.8 percent, had a traumatic brain injury (TBI) during the study, compared with about 1,600, or 2.2 percent, of the children and young adults in the control group.

Young people with ADHD were 4.6 times more likely to have a traumatic brain injury than their peers without ADHD.

While the study wasn’t a controlled experiment designed to prove whether or how ADHD might directly cause brain injuries, it’s possible the condition makes children more reckless with sports and leisure activities or less attentive when they’re driving cars or riding bikes, said study author Dr. Mu-Hong Chen, of Taipei Veterans General Hospital in Taiwan.

“Impulsivity is very much linked with risky health behaviors,” Chen said by email.

Worldwide, up to about seven percent of children and teens and two percent of young adults have ADHD, researchers note in the Journal of Adolescent Health. While the condition is characterized by a variety of social and behavioral problems that can make young people more accident prone, research to date has been mixed on the potential for ADHD to cause brain injuries or for ADHD treatment to reduce this risk.

About 0.2 percent of the youth with ADHD had skull fractures in the study, compared with 0.1 percent of other young people.

At the same time, 4.3 percent of children and young adults with ADHD had concussions, compared with 1 percent of other young people in the study.

But when ADHD patients took medication to manage the condition for at least one year, they were seven percent less likely to have a traumatic brain injury than people with untreated ADHD or people who took medication for three months or less.

“It is not clear if traumatic brain injury causes ADHD which then leads to repeat TBI or whether having ADHD puts a child at risk for behaviors which increase the risk for sustaining a TBI,” said Dr. Jack Tsao, a neurology researcher at the University of Tennessee Health Science Center and the Memphis Veterans Affairs Medical Center who wasn’t involved in the study.

But a key finding, he said by email, “is that starting a child on medications to reduce the symptoms of ADHD leads to a small decreased risk for initial injury and repeat TBI after the initial TBI.”

The study didn’t break down the risk of brain injury by age, making it difficult to say if the bigger problem might be kids on the playground, teens playing ball, or young adults driving cars, noted Anthony Kontos, research director of the sports medicine concussion program at the University of Pittsburgh Medical Center.

Still, parents of young children and teens can still take precautions to minimize the risk, Kontos, who wasn’t involved in the study, said by email.

Getting ADHD diagnosed and treated is a good start, Kontos advised.

“Children with ADHD who consistently take these medications are likely to have better attentional focus, which would minimize distractions and help maintain focus on relevant cues in the environment or while performing a task – such as playing a sport or on the playground or riding a bicycle,” Kontos added.

Proper protection during sports also matters.

“Helmets should always be worn by children engaging in at-risk activities such as cycling or skateboarding,” Kontos said.

SOURCE: Journal of Adolescent Health, online July 1, 2018.