Playing Professional Football, Concussion, and Cognitive Impairment Come Together

Yesterday (August 30, 2019) The Journal of American Sports Medicine published the results of research on the history of concussion and cognitive changes in NFL players.  In this magazine article, the authors interviewed the investigators.  The study found that the longer a player's career, the greater the risk he would develop cognitive problems.   It did not address Alzheimer's disease or dementia, but we discussed how these might be related to traumatic brain injury in Beating the Dementia Monster.  We will dig deeper into the subject in the second edition.

The study was conducted at the T.H. Chan School of Public Health (formerly the Harvard School of Public Health).  The investigation was conducted primarily by querying 13,720 NFL players, past and current, of which 3,506 responded.  A questionnaire asked players to self-report on ten symptoms, mostly focused on anxiety and depression.  From this the researchers determined a cognitively-related quality of life score.

The researchers found that the number of NFL seasons of play and playing position were associated with lasting neuropsychiatric health deficits.  They also found that poor cognition-related quality of life, depression, and anxiety seemed to be associated with concussion over time.  Twelve percent of players reported cognitive problems vs. two percent in the general population.  Players who played ten seasons or more were twice as likely to report problems.

While I don't doubt the findings, it occurs to me that there may be some skewing of their data.  If so, this possibility wasn't addressed in the abstract.  (Wasn't willing to pay $40 to get the whole article...)  The researchers sent the questionnaire to a substantial population of players, but only got back a quarter of them.  I wonder if the severity of symptoms might have either dissuaded players or encouraged them to return their surveys.  If so, the investigators' sample may not have been representative of the whole population of subjects.  Also, NFL players live a different lifestyle than most of the rest of us, so there could be other drivers for anxiety and depression.

Again, they did not (at least in the study abstract) relate their findings to Alzheimer's disease or dementia.  However, there is plenty of other research making that connection.  Something to bear in mind is that Alzheimer's disease begins a decade or two before the symptoms appear, so the worst may be yet to come for some of these players.