NPR's Sacha Pfeiffer speaks with a man who is concerned about CTE, and with neuroscientist Bob Stern, who explains why more cases of CTE may emerge decades after plastic helmets became commonplace.

Transcript

SACHA PFEIFFER, HOST:

There was grim news in the football world last week. The family of former NFL player Phillip Adams, who shot and killed six people before taking his own life in April, announced he had CTE - chronic traumatic encephalopathy. That's the degenerative brain disease believed to be caused by repeated head trauma. It can only be diagnosed after death, and it's been found in the autopsied brains of hundreds of former professional football players. Many of them suffered from cognitive or behavioral problems before they died.

But there's also a quiet population of everyday men and women who never played pro sports but worry they could be at risk of CTE. Some were amateur athletes or military veterans or had multiple head injuries from other causes.

A while back, I met a man who wonders if the rough way he played football when he was younger is catching up with him now. His name is Jeff Stanley. He's 49. He lives in Christiansburg, Va., and he's a project manager for a road and bridge construction company. Here's his story in his own words.

JEFF STANLEY: I started playing football, I guess, in third grade. I actually fibbed about my age and played a year earlier than I was supposed to, and then played all the way up through high school. And I wrestled collegiately at Virginia Tech. And then after college, I actually played a year of semi-professional football in Roanoke. Roanoke had a team at the time.

I'm not happy to say that I loved the contact and loved to hit hard when I was playing. I guess some would consider it dirty or unethical, you know, because when I played, I would rather hit somebody hard and have them lay there a while or get up staggering or whatever. Then I would score a touchdown. And there were two or three quarterbacks that I knocked out cold and were carted off, and that was a gameplan.

I don't ever remember anyone, any coaches or any adults, talking about how - that it would be destructive to me or have adverse effects later on. I never remember having any conversations or any thought about health concerns. Of course, in high school, we think we're invincible, anyway. There was a couple of times in my career that I was a little bit - you know, saw stars or something after a hit. And I can remember eighth grade, I hit a kid from William Bird down in Roanoke. And I walked back to their huddle instead of my own. And I shook it off real quick. And then I actually got it on video. It's pretty funny - or it's funny now. They had to point me in the right direction, get me back to the right huddle. That was late '80s, my high school football career.

My dad and I have talked about CTE a little bit. He was a really good high school football player and played football in college. And he played the game like I played the game, you know, with his head. But I've said to my wife and my dad - we've talked, and I just said, you know, I wonder if some of my forgetfulness or things like that are attributed to the way that I played sports - the mood swings and the kind of zoning out in meetings. You know, there's times that I'll sit through a whole conversation, and I've not paid a bit of attention to what the person was saying or been thinking about other things or feel like I forget key things with my job.

I'm sure that hitting people like that, I didn't help myself. I didn't getting any smarter about hitting people helmet to helmet. But I don't know. I would just - I'm not totally 100% ready to chalk my issues up to CTE yet. I've got a good life here and involved in all my kids' stuff. And I don't forget birthdays and anniversaries and things like that. So I feel like, on a scale, you know, I'm doing, I'm doing pretty daggone (ph) good. So I do think there is a population that's smaller of high school and collegiate athletes, even in wrestling, that I think have as good of a chance to be affected by it as some of the pro guys that are kind of forgotten. But I think there's a pride thing that probably keeps men from talking about things like that.

I think that, you know, it might be a sign of weakness. And I just don't know how that you would ever get people to come out and actually say, you know? I mean, I guess anonymous questionnaires would be the only chance or maybe the best way to get good honest answers, you know? But I just don't think that we'll ever really tap in truly to guys that maybe experience it or who even quietly fear CTE.

PFEIFFER: That was Jeff Stanley of Christiansburg, Va. And listening along with us to Jeff's story is Dr. Bob Stern, a neuroscientist at the Boston University School of Medicine and a co-founder of BU CTE Center. Bob, thanks for talking with us today.

STANLEY: Terrific to be on. Thanks, Sasha.

PFEIFFER: You just heard Jeff's story, and I'm sure it's a story you've heard many versions of before from other people. When you hear a story like that, how concerned do you think a person like Jeff Stanley should be about possibly developing CTE in the future?

BOB STERN: Well, you know, I think there's a lot of extra concern out there by people who shouldn't necessarily be concerned. What we're finding more and more is that the risk for CTE is directly associated with the overall exposure to playing football. But it's not necessarily those big hits that Mr. Stanley was concerned about. It's not necessarily those times where he, you know, used his helmet as a weapon and knocked out the quarterback. What we're finding more and more is that it's the overall amount of what we refer to as subconcussive hits, these repetitive blows to the head that don't result in symptoms, that don't result in the seeing stars or getting knocked out. It's the routine part of the game.

PFEIFFER: But if Jeff Stanley took big hits like he's describing, isn't it possible or even likely that he also took repetitive hits that weren't full concussions?

STERN: Yeah. You hit the nail on the head, so to speak.

PFEIFFER: Does that make him a CTE risk in the future?

STERN: Well, you know what? We're trying to figure that out. We're trying to figure out exactly what frequency, what strength, what type of hits really does lead to the most increased risk later on.

PFEIFFER: And I think this is a key point, that our understanding of CTE is still evolving. You and I could spend hours talking about that. But for now, the short summary is that CTE cannot be diagnosed until after death, and it has no treatment. Your center, BU's CTE Center, has diagnosed about 700 cases of CTE in roughly the last, I think, 15 or so years, maybe a little under. Bob, you have a theory for why CTE could only now be showing up in many former football players. It has to do with helmet technology. Would you tell us about that?

STERN: Yeah, and it's not really even about helmet technology. It's about the fact that helmets create this sense of invincibility that allows football players in particular to hit their heads over and over again. And the issue is this, that the plastic, hard-cased football helmets with facemasks were not used until the 1950s and 1960s. That's when they really started to be used routinely in the NFL and in college football. And those helmets were developed to prevent skull fractures, which they did, and they continue to do so very well. But those big helmets and facemasks allowed individuals to hit their head repeatedly against their opponent or get down to the ground without feeling any pain, thus creating that sense of invincibility.

PFEIFFER: If we think about the timeline of when these heavy-duty plastic helmets started showing up on playing fields, is the idea that if you wore one of those in the '60s, '70s or '80s, only now have you aged to the point where you might begin to see the damage that was caused by that, by using that helmet decades ago?

STERN: Yeah, that's exactly it. You know, we don't really have a good grasp of the overall epidemiology of CTE at this point, but it is indeed possible that there are millions of older adults who are at high risk for CTE or other long-term neurological conditions due to their history of exposure to these repetitive head impacts.

PFEIFFER: I've done a lot of reporting on CTE, and I've talked to many people who think that the research isn't far enough along to justify the level of fear over CTE among some people. How do you feel about that?

STERN: I agree. I think that we still have a huge number of answers out there that we have to find and that little kids or their parents who, after a kid has a single concussion or two concussions, they get this fear that, oh, little Johnny (ph) is going to get CTE - those are the fears that we have to squelch. We just don't know enough about how much exposure at what level.

What I think is becoming clearer, however, is that people who had a lot of these hits are at increased risk. And the greater the overall number of years and the number of hits people get, the greater the risk there is in the study after study for developing this disease.

PFEIFFER: That's Dr. Bob Stern, a neuroscientist at the Boston University School of Medicine and a co-founder of BU CTE Center. Thank you very much.

STERN: Thank you very much, Sacha.

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