Kids who played tackle football at a young age weren't at increased risk for prolonged or worsened concussion symptoms as college players, researchers said.
In adjusted models, the estimated age of first exposure to American football -- defined as a player's age at the time of concussion diagnosis minus his self-reported number of years playing football -- was not related to longer symptom recovery, worse balance, or worse cognitive performance soon after concussion, reported Thomas Buckley, EdD, of the University of Delaware in Newark, and co-authors in .
In unadjusted regression models, younger age of first football exposure was associated with worse visual motor speed scores (R2 0.031, P=0.012) at 24-48 hours following injury and better somatization sub-scores (R2 0.014, P=0.038) after symptoms resolved. Effect sizes were small.
"Our study in NCAA football players, some who started playing tackle football as early as age 5, found no link between playing football earlier in life and worse recovery from concussion," Buckley said in a statement.
"Our results may be reassuring for players and parents, but it is important to note that we were looking at one concussion at one point in time and current testing may not be sensitive enough to detect subtle changes," he added.
"While the study of young collegiate players is interesting, it does not shed light on the later-life neurological disturbances that affect American football players and boxers," observed Ann McKee, MD, chief of neuropathology at VA Boston Healthcare and director of the CTE Center at Boston University, who wasn't involved with the research.
"Similar findings from this group of authors show limited clinical consequences in young, active, otherwise healthy NCAA football players," McKee told Ƶ.
"The age at which you start to play football likely has more important implications in the setting of aging and age-related neurological disorders, which are not addressed by the study," she pointed out.
Research about early exposure to football has yielded mixed results, with some studies suggesting head impacts at young ages raise the risk of negative , and others saying age of first exposure , noted Robert Lynall, PhD, of the University of Georgia in Athens, and Kevin Barrett, MD, of the Mayo Clinic in Jacksonville, Florida, in an .
In the short term, it's unclear how early exposure may affect concussion recovery, "limiting the clinician's ability to prognosticate and tailor post-concussion management based on prior duration of exposure," they wrote.
Concerns about long-term consequences from early exposure to tackle football have prompted calls to "shift to a standard of flag football before age 14," as one 2018 report put it.
Survey data published last year showed that most parents supported age limits for tackle football.
In their study, Buckley and colleagues assessed 621 NCAA football players from 30 schools which were part of the NCAA-Department of Defense Concussion Assessment, Research and Education () Consortium. Among players who had multiple concussions throughout their CARE Consortium participation, only their first concussion was included in analyses.
All participants were diagnosed with recent concussion. All had baseline testing before concussion and evaluations within 6 hours of concussion. Of the total sample, 294 players were evaluated for symptom severity 1 to 2 days after concussion, and 327 were evaluated once concussion symptoms resolved.
Athletes were 19 years old and reported first playing tackle football at a mean age of 10. Nearly half -- 46% -- had a prior history of concussion. Most (73%) concussion diagnoses occurred during practices and training.
Short-term outcome measures included the number of days until asymptomatic; Immediate Post-Concussion Assessment and Cognitive Testing () scores of verbal memory, visual memory, visual motor speed, reaction time, and post-concussion symptom severity; ; and Brief Symptom Inventory 18 () global scores for overall psychological distress and subscores for somatization, depression, and anxiety.
Age of first football exposure was not correlated with the number of days until symptoms resolved, balance, depression, anxiety, or other ImPACT scores besides visual motor speed. At 24-48 hours, post-injury symptom severity was the best predictor of somatization (R² 0.222), anxiety (R² 0.157), BSI-18 global scores (R² 0.278), and ImPACT symptom severity change scores (R² 0.425).
The study is limited by athletes' estimation of their age when they started playing tackle football. The minimum estimated age for football exposure in this study was 5 because that's the youngest age for Pop Warner youth football; athletes who reported an estimated age earlier than 5 were excluded. The researchers also did not account for exposure to other contact sports or for player positions.
The findings are for short-term post-concussion outcomes only and must be viewed in that light, McKee emphasized. "To conclude from an unaltered concussion recovery time in young football players that long-term health is unaffected is completely unsubstantiated," she said.
Disclosures
The study was supported by the Grand Alliance CARE Consortium, funded by the NCAA and the U.S. Department of Defense.
Researchers reported relationships with the Grand Alliance CARE Consortium, BioDirection, Inc., Sway Operations, Highmark, ImPACT Applications, Inc., CNS Vital Signs, Psychological Assessment Resources, National Football League (NFL), Harvard Integrated Program to Protect and Improve the Health of NFL Players Association Members, Heinz Family Foundation, Boston Bolts, Mooney-Reed Charitable Foundation, Spaulding Research Institute, Major League Soccer, NFL Head, Neck & Spine Committee, Ivy League-Big Ten Concussion Summit, NCAA, U.S. Dept of Defense, UCLA Steve Tisch BrainSPORT program, NIH NINDS, UCLA Brain Injury Research Center, Easton Clinic for Brain Health, NINDS Neural Analytics, Richie's Fund, NBA, NFL-Neurological Care Program, NHLPA, Novartis Pharmaceutical, and USSF.
The editorialists reported no disclosures.
Primary Source
Neurology
Caccese J, et al "Estimated age of first exposure to American football and outcome from concussion" Neurology 2020; DOI: 10.1212/WNL.0000000000010672.
Secondary Source
Neurology
Lynall R, Barrett K "Recovery after football-related concussion: Does age of first exposure matter?" Neurology 2020; DOI: 10.1212/WNL.0000000000010673.