However, younger age and a history of attention-deficit/hyperactivity disorder (ADHD) did predict decline in cognition among the young football players. Longer-term effects are unknown and require further research.
“The study is showing us that sub-concussive impacts don't seem to be associated with changes in neurocognitive function over two seasons of youth football,” said lead author Sean Rose, M.D., a pediatric sports neurologist and co-director of the Complex Concussion Clinic at Nationwide Children's Hospital in Columbus, Ohio. “And we're finding that other factors, such as ADHD and younger age, are more predictive of worsening scores on our pre- and post-season tests.”
Rose and colleagues studied a sample of 166 youth tackle-football players over two seasons: 70 primary-school players aged 9 to 12 years and 96 high-school players aged 15 to 18 years. Sensors were placed in their helmets to record the number as well as the intensity of impacts to the head. All participants completed assessments on a variety of neurological, cognitive (including memory and attention), and behavioral outcomes before and after each football season.
In the subgroup of 55 youth who played in both seasons, neither cumulative impact nor impact intensity predicted change scores from preseason 1 to post-season 2 on any outcome measure. However, younger age did predict worse outcomes in some measures, though these changes were independent of head impacts. Also, a history of ADHD was associated with reduced scores on several cognitive measures and an ADHD symptom self-reporting scale.
“When trying to determine the effects of repeated, sub-concussive head impacts, prospective outcomes studies are an important addition to the existing retrospective studies,” said Rose in a prepared statement. “We designed this study to include a wide variety of neurocognitive outcomes tests to give us new insights into how repeated hits might influence outcomes.”
Despite the study findings, Rose said the longer-term effects of repeated impacts from tackle football on young people’s brains is unknown “We remain concerned about repetitive head impacts in children, and longer follow-up times are necessary to look for delayed effects on neurocognition,” he said.
>For related information, see the Psychiatric News article “Age When Football Hits Began May Determine Future Cognitive Problems.”