Playing tackle football before the age of 12 is associated with an increased risk of developing memory and thinking problems in middle age — at least among former professional football players, according to a study published online Wednesday in the journal Neurology.
The study, led by researchers at the Boston University School of Medicine, involved 42 retired NFL players, aged 40 to 69, who had experienced memory and thinking problems for at least six months. Half had begun playing tackle football before age 12 and half had not. Based on years of football played, both groups were also estimated to have had similar numbers of concussions.
The players were given a battery of neuropsychological tests that measured a variety of cognitive abilities, such as mental flexibility, memory and intelligence. When the results of those tests were analyzed, the study found that those players who had started football before the age of 12 scored “significantly worse” on all the tests measured, even after controlling for education, length of time playing football and the age of the players when they took the cognitive tests. For example, they recalled fewer words memorized 15 minutes earlier, on average, and made more repeated errors on tests of mental flexibility than the players who had started football at a later age.
On several of the tests, the difference in scores between the two groups was more than 20 percent (although, compared with the general population, both groups often scored below average).
“These findings suggest that sustaining repeated head impacts during a critical neurodevelopmental period may increase the risk of later-life cognitive impairment,” the authors of the study conclude.
The sport with highest injury rate
As background information in this study notes, 70 percent of all football players in the United States are under the age of 14. Football has the highest injury rate of any team sport, and each child aged 9 to 12 who plays the sport experiences an average of 240 head impacts during a single season.
Scientists used to think that the developing brain could recover better than the adult brain after a head injury like a concussion. Today, however, it is widely acknowledged that the brains of children and teens are even more vulnerable than the adult brain to the long-term effects of such injuries.
And one of the most critical periods for that vulnerability is between the ages of 10 and 12, the authors of this new study point out.
That doesn’t mean, however, that children who start playing football after age 12 are free from these concerns. All children and teens playing football are at risk of long-term brain damage — even when the child appears to have fully recovered from a concussion.
“While the rate of intellectual development may return to normal following pediatric brain injury, the loss of normal development time during recovery may cause the injured child to fall behind and never return to the levels of his or her uninjured peers,” the study’s authors explain. “Children may appear to fully recover from concussions due to functional compensatory mechanisms despite a lack of neuronal recovery.”
Are parents listening?
This study, like all others, has its limitations. Its design does not make it possible to draw a causal link between playing football at an early age and later cognitive problems — even among professional players. In addition, a relatively small number of players were involved, and all head injuries experienced by each player at each stage of his life can’t be known for sure. The results of this study could, therefore, reflect the total number of head injuries that the players experienced during their lifetime rather than the age at which they were exposed to those injuries.
Generalizing these results beyond professional football players is also difficult, as the authors themselves acknowledge.
Still, as a commentary accompanying the study emphasizes, “These data add to the concern about the safety of football in children.”
Whether parents are getting that message is unclear. Some parts of the country are apparently seeing a decline in the numbers of young people participating in youth football leagues, but others aren’t.
And as the Associated Press reported last summer, although almost half of parents polled by that organization said they weren’t comfortable with their child playing football, only 5 percent “said they have discouraged their child from playing in the last two years as concern over head injuries has increased at all levels of the game.”
If the mounting scientific evidence about the long-term risks of playing football (no matter what protective gear is worn) isn’t enough to dissuade parents from letting their children onto the field, perhaps the words of former Chicago Bears head coach Mike Ditka will be. When asked earlier this month if he would let an 8-year-old son of his today play football, he quickly said no.
“I think the risk is worse than the reward,” he said. “I really do.”
You’ll find an abstract of the new study on Neurology’s website. The journal is published by the Minneapolis-based American Academy of Neurology, which also offers a “Sport Concussion Toolkit” on its website.