Football’s reputation has taken some serious hits lately. The onslaught began in 2002 when forensic pathologist Bennet Omalu found signs of a neurodegenerative disease called chronic traumatic encephalopathy (CTE) in the brain of former Pittsburgh Steelers center Mike Webster after Webster’s death from suicide at age 50. Since then, signs of CTE have turned up in post-mortem exams of several other former NFL players, and concerns have grown about the potential long-term risks of concussions and other head injuries. The NFL has insisted that the game is safe, but last year, the league settled a class-action concussion lawsuit with former NFL players worth $870 million. And just last month, San Francisco 49ers linebacker Chris Borland announced his early retirement, citing concerns about the long-term effects of repetitive head injuries.
While sports fans debate whether football can survive its concussion crisis, researchers are still trying to understand the underlying science of concussions and related brain injuries. Researchers at Boston University have created a “brain bank” to study CTE, and a Harvard study funded by the National Football League Players Association will follow former football players to examine an array of health measures over their lives.
In an editorial published March 24 in the medical journal BMJ, Chad Asplund, director of sports medicine at Georgia Regents University, and Thomas Best, professor and chairman of sports medicine at Ohio State University, examined the current state of the science and asked whether brain damage is an inevitable consequence of football or an avoidable risk.
I spoke with Asplund about what we know and what we don’t know about football and brain injuries.
Christie: Common sense tells us that football must be pretty bad for the brain — after all, you have a bunch of men knocking each other down. Now you have parents taking their kids out of the game and Chris Borland opting to retire early out of fears about head injuries. But is it possible that we’re getting ahead of the evidence here?
Chad: That was the point of our editorial really — the media gets ahold of some of these things and blows it way out of proportion. Mike Webster, Junior Seau, Andre Waters — some of these were sensational suicides in athletes that were right at the end of their careers. And [the media says], “Oh, by the way, their autopsies show that their brains weren’t normal and they played football, so therefore this must have been caused by football.”
I think parents are getting the wrong message. The media’s portraying this [causation] line — football equals brain injury — before the science has gotten there. The public doesn’t want to hear that we’re doing our best to try to gather the best evidence to give you the best answer, but it may take 10 or 12 or 15 years. That’s a hard message.
Christie: It’s sort of amazing that despite all the attention being paid, we still don’t have a way of definitively diagnosing concussion. Do we even know what a concussion is?
Chad: That’s a million-dollar question right there. The hardest piece of all of this is that we don’t know what a concussion is, other than that it’s a constellation of symptoms that occur after force that’s transmitted to the brain. But you can’t cut people’s heads open to look in at what’s happening, so we don’t really know.
Some concussions present with strictly memory problems, and some present with weakness, dizziness and things like that. We know that different parts of the brain are affected, which then give a different constellation of symptoms. And so it’s hard to say that if my head got hit and your head got hit the same way, would we exhibit the same symptoms and would that mean we had the same injury? It’s very hard to move forward with science research and evidence if you don’t know what the problem is.
Christie: What about CTE? How certain are we that it’s a real condition?
Chad: There’s solid evidence to show that, yes, it is a real condition. [Ann] McKee at Boston University has set out diagnostic criteria. It’s an abnormality that is seen in people who have had multiple traumatic injuries to the brain. It’s defined by these protein depositions or neurofibrillary tangles that deposit in certain portions of the brain like the basal ganglia, and it’s similar, but different, from the sorts of things found in Alzheimer’s disease.
Christie: A recent review by Joseph Maroon at the University of Pittsburgh found that over the past 60 years, there had been only 63 cases of football players with CTE confirmed by autopsy. That number is minuscule compared to the number of people who’ve played the game, so can we really link CTE to football?
Chad: Millions of people have played football, so it’s very hard to draw a straight line to say football equals chronic traumatic encephalopathy. When you look at the CTE brains that [McKee’s group has] in Boston, they haven’t really analyzed different [risk factors]. Were there other things that may have led up to this? Was there depression, anxiety or underlying mental health disorder? Was there substance use? The only way to make a CTE diagnosis right now is after you’re dead — that makes it really complicated.
Christie: And it’s only been recently that we started thinking about CTE. A lot of former players are still living and so can’t be diagnosed with an autopsy. Are the small numbers here just a matter of how we’re looking for the condition, or are they some reflection of CTE’s true incidence?
Chad: Well, that’s a hard thing to figure out. The best way to determine incidence of a disease is to have an accurate number of people over the total number of people that have participated. If you go to the high school or college level, that denominator is always moving. Professionally, it gets a little bit easier. But is this just the tip of the iceberg? All these people who, let’s say, played in the ’80s and ’90s — when they die, are we going to suddenly have an exponential increase in these diagnoses? At this point, it’s hard to say.
Christie: In your editorial, you point out that while all autopsy-verified cases of CTE have been in people with a history of repetitive blows to the head, not all of them have had a documented history of concussion. That seems counterintuitive.
Chad: Yes and no. I’ve been covering football now for 15 or 16 years, and early on, if you had some sort of head injury, they would downplay it by calling it a “ding” or a “bell ringer.” If you said to your athletic trainer or coach, “I have a concussion,” they would take you out of the game. And so, for years, the total number of concussions has thought to have been under-reported. So some of these could have been undiagnosed concussions.
But we’re learning from the helmet data that a lot of little trauma is worth a lot more than one big trauma. If you watch football, you can see some pretty massive hits that happen on the field and the player is normal. But then you have a seemingly minimal blow and the player gets up and walks toward the wrong sideline or the wrong bench.
I think the helmet data is going to be helpful to determine how many of these little head traumas do players get each year. And that’s going to be helpful in the long term to determine: Is there a load of head traumas or number of traumatic incidences that you can [safely] have?
Christie: You mention the helmet data, but the NFL has discontinued the use of accelerometers, right?
Chad: They have. There was some disagreement over reliability and how the impacts were being measured. I’m not generally a conspiracy theory guy, but it’s very interesting that the NFL for the longest time had their own committee that was coming out with these studies to say, “No! Football is safe.” Then they refute this accelerometer data, and they want to stop the studies with the accelerometer. Maroon, who wrote the systematic review, was on the NFL’s head trauma committee. So it’s interesting how that all falls into it.
Christie: Retired NFL players who began playing football before age 12 show greater levels of cognitive impairment in their 40s, 50s and 60s than those who started later. What can we glean from this?
Chad: I think there’s two possibilities. You could look at it in the sense that the brain is still developing, and does early trauma to the brain lead to later life problems? Or, does it mean if you started before 12, you’ve just had a longer exposure to sub-concussive or concussive head trauma as opposed to somebody who didn’t start until 15, 16, 18?
Christie: What do we know about brain injuries and mood disorders like depression?
Chad: [Kevin] Guskiewicz, back in ’07, looked at a survey of 2,500 retired football players and found that football players with three or more concussions were three times more likely to be depressed. So there’s perhaps a link between concussion and depression.
Christie: At this point, what can we say about the risks of football? Are brain injuries an inevitable part of the game or an avoidable risk?
Chad: I think it’s an avoidable risk, but we need to develop the science, and we need to change the rules of the game. The Heads Up Football initiative has done a great job with youth football, teaching people to tackle the right way. The other piece is continuing to get it out there that it’s OK to admit you have a concussion. Better diagnostics, athletes being more willing to admit they have a concussion, better return-to-play guidelines, tackling the right way, reducing avoidable head impacts — all of that can make football safer so that it is an avoidable issue.
I was just in New York City at the Collaborative Solutions for Safety in Sport, and Kevin [Guskiewicz] was there talking. One thing he said is that his son plays football and he’s fine with that. The only thing he wanted was to make sure his son had a helmet that fit. Kevin is probably more aware of the science of concussion than anyone else, and if he’s willing to let his son play football, then the information is probably not definitive enough to draw a line that says football equals brain damage.
CORRECTION (April 2, 4:22 p.m.): An earlier version of this article incorrectly said Bennet Omalu found signs of CTE in the brain of former Pittsburgh Steelers center Mike Webster in 2005. Omalu found signs of CTE in 2002.