Map of life expectancy at birth from Global Education Project.

Wednesday, August 02, 2017


I've written about the North American warrior game here before, and if you've been hanging around long enough you know that my views on it have changed along with the evidence. Our biggest worry used to be spinal chord injuries. Rule changes to prohibit using the helmet as a ram, and coaching at the youth level to emphasize keeping the head up during contact, greatly reduced that risk.

But it's time now to face the truth: no conceivable rule changes that would let you keep on calling it the same game can keep the players' brains from turning to cornmeal mush. The fundamental problem is the helmet. This may be counterintuitive. It seems that the helmet is there to protect the brain, but the opposite is true. The helmet protects the skull and the face, which enables the head to collide forcefully with other players and the ground. When that happens, the brain sloshes around and smashes against the inside of the skull. Rugby players do get concussions and are apparently at risk for Chronic Traumatic Encephalopathy, but not as high a risk as North American football players precisely because they don't wear helmets. That forces them to protect their heads.

The linked study in JAMA has gotten a lot of publicity. In case you've been too obsessed with a certain orange idiot's twitter feed to pay attention, the researchers got families to donate the brains of deceased football players. 110 out of 111 met the diagnostic criteria for CTE based on microscopic examinations of their brain tissue.

Now, this doesn't mean that nearly 100% of NFL players will ultimately get the disease. The families donated the brains because they were worried, and indeed, basically all of these players had observable pathology when they were alive:

Among the 111 CTE cases with standardized informant reports on clinical symptoms, a reported progressive clinical course was common in participants with both mild and severe CTE pathology, occurring in 23 (85%) mild cases and 84 (100%) severe cases (Table 3). Behavioral or mood symptoms were common in participants with both mild and severe CTE pathology, with symptoms occurring in 26 (96%) mild cases and 75 (89%) severe cases. Impulsivity, depressive symptoms, apathy, and anxiety occurred in 23 (89%), 18 (67%), 13 (50%), and 14 (52%) mild cases and 65 (80%), 46 (56%), 43 (52%), and 41 (50%) severe cases, respectively. Additionally, hopelessness, explosivity, being verbally violent, being physically violent, and suicidality (including ideation, attempts, or completions) occurred in 18 (69%), 18 (67%), 17 (63%), 14 (52%), and 15 (56%) mild cases, respectively. Substance use disorders were also common in participants with mild CTE, occurring in 18 (67%) mild cases. Symptoms of posttraumatic stress disorder were uncommon in both groups, occurring in 3 (11%) mild cases and 9 (11%) severe cases.

Cognitive symptoms were common in participants with both mild and severe CTE pathology, with symptoms occurring in 23 (85%) mild cases and 80 (95%) severe cases. Memory, executive function, and attention symptoms occurred in 19 (73%), 19 (73%), and 18 (69%) mild cases and 76 (92%), 67 (81%), and 67 (81%) severe cases, respectively. Additionally, language and visuospatial symptoms occurred in 54 (66%) and 44 (54%) severe cases, respectively. A premortem diagnosis of AD and a postmortem (but blinded to pathology) consensus diagnosis of dementia were common in severe cases, occurring in 21 (25%) and 71 (85%), respectively. There were no asymptomatic (ie, no mood/behavior or cognitive symptoms) CTE cases. Motor symptoms were common in severe cases, occurring in 63 (75%). Gait instability and slowness of movement occurred in 55 (66%) and 42 (50%) severe cases, respectively. Symptom frequencies remained similar when only pure CTE cases (ie, those with no neuropathological evidence of comorbid neurodegenerative disease) were considered (eTable in the Supplement).

Sure, a lot of people develop dementia, but not this young. The median age at death was 66, the youngest was 47,  and 3/4 were younger than 76. You would most definitely not expect to see such a prevalence of brain damage in the general population in that age cohort. So granted, we don't know the actual prevalence among football players, and it's likely less than it appears from this sample. But . . .

The danger is obviously real and it's turning out to be unacceptable to a lot of players. We're seeing a spate of early retirement from the game. Sure, kids who are already dreaming of NFL glory are unlikely to give up playing in high school and college, but we have to expect that fewer and fewer players will allow their boys to take up the game. That, I think, is how the game will ultimately die, when the pipeline of players dries up. Regretfully, I have to say I hope that it will.


Smith said...

Good column. While we're at it, I also hope that in addition to football, religious and other proselytizing will dry up and die eventually. Evangelizing for any cause--i.e., Christianity or "Objectivism," the "religion" of Ayn Rand followers (who, curiously, largely claim to be atheists)--also seems to have a way of shrinking people's brains to cornmeal mush.

Cervantes said...

Rather OT, but I agree with you. Libertarianism, like the concept of God, is internally inconsistent and inconsistent with observable reality.

kathy a. said...

The "mush" with CTE is physical changes, as well as behavioral and cognitive changes, and generally early onset. There are not great systems in place to help the affected people or their families cope; and nobody expects those kinds of changes earlier in life. There is overlap with conditions like frontotemporal dementia (FTD), because the symptoms and challenges are so similar when the frontal and temporal lobes are affected -- and, the cause can't actually be determined until autopsy. Not even then, unless a person's brain is donated for research, because the kind of investigation of changes in the brain's tissues is so specialized.

So, the results of this study were of great interest to my group dealing with FTD.

Cervantes said...

My father had FTD, and ultimately died from it. His disease was triggered by a stroke. So yeah, I know what it is. Just about the worst thing any family can go through.

Anonymous said...

If you were to design physical games from scratch without any regard to traditional and cultural influences and norms, everyone would agree with your assessment of the terrible evils of American football.

They would also agree to to the evils of automobiles, motorcycles, skydiving, scuba diving, spelunking, zip-lining, carnival rides, dodge ball (thank God they've saved us from *that*!) and anything else that could involve any risk of injury.

I would suggest that you wear a rubber helmet to work just in case you fall.

Cervantes said...

It is certainly true that we take all sorts of risks in life. People have to balance their tolerance for risk with whatever reward they get for risky activity. The issue here is that the knowledge that playing football presents such a high risk of such an extremely unpleasant outcome is new -- it changes the risk/reward relationship from what it was previously presumed to be. How people will respond to this information is the question, and it looks like a lot of them -- including men who are already making millions in the NFL -- are deciding it isn't worth it.