Do repeated head injuries during play impact cognition and behavior?

Repeated concussions have been linked to severe negative neurological outcomes. Is there a similar experience with repeated impacts on the head during contact sports?

With the growing knowledge of the potential damage caused by repeated head injuries, which can include chronic traumatic encephalopathy, from contact sports and in particular football, many parents have become increasingly wary of the potential for permanent damage to their child as a result of athletic participation. A report examines whether repetitive head impacts in youth tackle football over the course of 4 seasons were linked to cognitive and behavioral difficulties.1

Investigators conducted their prospective cohort study from July 2016 to January 2020 for a total of 4 seasons. They recruited players from 4 teams that included 5th and 6th graders. The age group was selected to both prioritize young age and ensure a wide potential pool of participants due to large team size. Head impacts were measured with helmet-based sensors at practices and games. They were summed to provide the cumulative head impact gravitational force equivalents per season. Cognitive and behavioral assessments were run before and after each season. Any pre-existing conditions were noted at the initial pre-first season visit. Interval concussions were recorded at the follow-up visits. Participants informed investigators about other contact sports participation at the final visit.

A total of 70 boys aged 9 to 12 years were enrolled in the study; 18 of them completed all 4 years of the study. In each of the 4 seasons, 1 player suffered a concussion and the same player had a concussion during seasons 2 and 3. For players who had a concussion, the symptoms were resolved and they had been medically cleared before the post-season assessment. The investigators stated that the premorbid diagnoses, pre-season 1 outcome measurements, and cumulative impacts in season 1 had no difference between the players who completed all 4 years of assessment and those who dropped out. Higher cumulative impacts were tied to lower self-reported symptom burden (β = −0.6; 95% CI, −1.0 to −0.2; P = .004). Following correction for multiple comparisons, they found no further association between impacts and outcome measures. Furthermore, premorbid conditions such as attention-deficit/hyperactivity disorder, anxiety, and depression were linked to worse cognitive or behavioral scores at multiple points in the investigation, whereas a history of concussion or premorbid headache disorder was less frequently tied to negative outcomes.

The investigators concluded that premorbid conditions were more associated with cognitive and behavioral outcomes than cumulative impact. More research may be needed to further confirm the results, but the study does offer some reassurance to parents of children who are involved in contact sports.

Reference

1. Rose S, Yeates K, Nguyen J, Pizzimenti N, Ercole P, McCarthy M. Exposure to head impacts and cognitive and behavioral outcomes in youth tackle football players across 4 seasons. JAMA Netw Open. 2021;4(12):e2140359. doi:10.1001/jamanetworkopen.2021.40359