Last week, a report updated the sad state of former Northwestern and Bears running back Mike Adamle, who may be better known as a sportscaster for multiple Chicago television outlets. Now 70, Adamle was forced to retire from his second career in 2017 due to the effects of dementia, “a result of the brain rattling concussions he suffered playing (football).”
The science, though, says something completely different. Study after study has demonstrated that there is no correlation between concussions and chronic traumatic encephalopathy (CTE), the disease that presumably underlies Adamle’s dementia.
Last month, in a New England Journal of Medicine editorial, Boston University CTE Center neuropsychologist Robert Stern wrote, “Rather, the total duration of exposure to repetitive head impacts, including ‘subconcussive’ injuries without symptoms, has been associated with neuropathology, (signs) of neurodegeneration, and cognitive and neuropsychiatric symptoms.”
In short, the risk factor for CTE is years of playing a contact or collision sport, not number of concussions.
Stern’s commentary accompanied a study published on the incidence of neurodegenerative disease among retired Scottish professional soccer players.
Conducted at the University of Glasgow, the study found that playing soccer at its highest level offered significant protection later in life against heart disease and lung cancer. Unfortunately, the sport made death from any neurodegenerative disease 3.53 times more likely than normal. The risk of Alzheimer’s disease was 5.07 times greater and amyotrophic lateral sclerosis (Lou Gehrig’s Disease) 4.33 times.
“These results,” Stern continued, “are similar to those from a study involving National Football League players conducted by the Centers for Disease Control and Prevention, in which all-cause mortality was lower among former NFL players than in the general population but neurodegenerative mortality was higher.”
As a result of the Glasgow study, the organizing body for youth soccer in Scotland is proposing a ban on heading the ball for players under the age of 11, which would mimic a similar measure in the United States that dates back four years.
Meanwhile, at least two state legislatures in the United States are currently considering bans on youth tackle football — prior to eighth grade in Massachusetts and before age 12 in New York.
Stern’s editorial would seem to suggest that such bans are not so crucial for preventing CTE.
“It is not possible to generalize (these) findings among male former professional soccer players to participants in recreational, amateur, or collegiate-level soccer," Stern wrote. "Parents of children who headed the ball in youth or high school soccer should not fear that their children are destined to have cognitive decline and dementia later in life.”
Multiple studies of youth and high school football have demonstrated no increase in neurodegenerative disease among those who did not go on to college or professional play.
This is not to say that the separate issue of concussion is to be ignored. While there may be no correlation between the injury and CTE, there is ample evidence that mismanagement makes multiple complications — such as prolonged recovery, re-injury, and the rare but often fatal and always disabling second impact syndrome — more likely.
Consequently, it is worth noting another study published last month, this one in Pediatrics (the journal of the American Academy of Pediatrics). It examined concussion rates across 20 high school sports.
The National High School Sports-Related Injury Surveillance Study, currently managed at the Colorado School of Public Health, has been ongoing since the 2005-06 school year and this most recent of its works looked at the epidemiology of concussion for the 2013-14 through 2017-18 school years.
Over the course of five years, concussion rates were generally higher across all sports when compared with previous time blocks. The study’s authors attributed the increase to better detection, thanks to all 50 states finally having laws on the books regulating the management of sports-related concussion.
On a more positive note, the researchers discovered that concussions during football practices and recurrent concussions in all sports fell steadily during the five-year period and in comparison to previous periods.
As in the previous studies, football had the highest rate of concussion with 10.4 injuries per 10,000 athlete exposures, with an athlete exposure being one athlete participating in one practice or game. However, girls soccer and boys ice hockey followed closely with 8.19 and 7.69 injuries, respectively.
Strategies to reduce these numbers are worth pursuing, while keeping in mind the risks of playing in high school are not of the long-term nature seen at the professional level.