Retired pro soccer players: heading frequency and player position associated with risk of cognitive impairment and dementia
By Keya Mockencherry. This article was initially published in the 8/24/23 edition of our Concussion Update newsletter; please consider subscribing.
A study published in JAMA Network Neurology found that “repetitive heading during a professional soccer career is associated with an increased risk of cognitive impairment later in life” and self-reported dementias in retired male professional soccer players. Authors Espahbodi et al. note that previous research provides evidence that repeated subconcussive trauma caused by heading a soccer ball has a cumulative damaging effect on one’s brain health, and in active players, a one-time session of heading the ball 20 times “can cause immediate and measurable effects on cognitive ability and function.”
This UK nationwide cross-sectional study included 468 retired male professional soccer players over 45, with a median age of 63.68. The risk of cognitive impairment and self-reported dementia or Alzheimer’s disease increased with self-reported increased frequency of headers per training or match. Retired players who reported more than 15 headers per training session or match had more than 3 times the risk of cognitive impairment compared to those reporting 0-5 headers per training session or match. The authors also found an increased risk of cognitive impairment and self-reported dementia/Alzheimer’s based on player position, with defenders having the highest risk––however, these results were not statistically significant. Those reporting a concussion with loss of consciousness had more than 3 times the risk of cognitive impairment.
The study participants completed the FOCUS self-reported questionnaire, which consisted of questions within 3 bands of heading frequencies (0-5, 6-15,>15 times per typical game or training session). It also asked participants whether they had sustained a concussion from soccer. If they answered yes, researchers asked the following questions: “How many times and how many times did the concussion involve (1) loss of consciousness, (2) loss of memory, and (3) hospitalization.”
The player’s cognitive function was assessed using the Telephone Interview for Cognitive Status-modified (TICS-m), an instrument focusing on learning and memory to determine cognition. Players received scores out of 21, with higher scores indicating better cognition. Researchers also conducted, through the telephone interview, the Hopkins Verbal Learning Test, verbal fluency, and assessed independent activities of daily living. Physician-diagnosed dementias were self-reported in the questionnaire as well.
Results showed that 114 participants reported a heading frequency of 0 to 5 times, 185 participants 6 to 15 times, and 160 participants reported heading the ball more than 15 times in a match. In the 0-5 frequency group, the cognitive impairment was 9.78%, 14.78% in the 6-15 frequency group, and 15.2% in the >15 group. The study authors also looked at heading frequency in training sessions; cognitive impairment was 3.4 times greater for those reporting >15 headers per training session compared to those reporting 0-5 headers per training session. Overall, the findings suggest that prolonged repeated heading over a professional career is a risk factor for cognitive impairment and self-reported dementias in retired UK soccer players.
