Researchers from the Department of Veterans Affairs and Boston University found a brain disease known as chronic traumatic encephalopathy, or CTE, in 96 percent of deceased NFL players they examined. The disease comes from repeated trauma to the head and can lead to dementia, memory loss and depression. Dr. Steven Erickson of the Banner Concussion Center in Phoenix will discuss the issue.
TED SIMONS: Researchers from Boston University and the Department of Veterans Affairs have found a particular brain disease in 96% of deceased NFL players examined. The disease comes from repeated head trauma and can lead to dementia, memory loss and depression. Here with more is Dr. Steven Erickson of the Banner Concussion Center in Phoenix, good to have you here thanks for joining us. What is chronic traumatic encephalopathy?
STEVEN ERICKSON: CTE is a chronic de-genitive changes to the brain, you can see on pathological slides. When you examine brains after somebody is deceased.
TED SIMONS: You can only really get this picture after the patient is deceased, correct?
STEVEN ERICKSON: Correct. Right now we're trying in medicine to identify persistent deficits. But right now the diagnosis is post-mortem.
TED SIMONS: Does it hit certain parts of the brain that deal with memory loss and depression or does it cover the entire brain?
STEVEN ERICKSON: It depends on the individual. There are certain parts of the brain that are more susceptible than others.
TED SIMONS: As far as the NFL players, 96% -- again, these are deceased NFL players that families agreed to having them examined. I imagine so. Traits they were concerned about were there to begin with, correct?
STEVEN ERICKSON: Correct. There's a selection bias. We're looking at people whose families suspected there was something along these lines. 97% sure enough showed changes on the slides.
TED SIMONS: How advanced were the changes?
STEVEN ERICKSON: I don't know specifics, I have not seen the slides. But there is evidence for it in 97% of the brains examined.
TED SIMONS: As far as the people examined, do we know if any of these folks were symptom free? Sounds like most of them had symptoms or the families wouldn't have agreed to the study.
STEVEN ERICKSON: That's where we don't want to jump to conclusions based on this evidence. We don't really know the histories of these folks. We don't know how many concussions they sustained, how many years of play they participated in, we don't know what symptoms they were having prior to their death. There is a selection bias. Clearly it's a pathologic diagnosis that we're all concerned about in sports medicine. But there's other research that shows that the cognitive deficits or the persistent problems are not ubiquitous in former NFL players. There's one study that shows that 60% of former NFL players in their sixties have no cognitive decline compared to age match controls.
TED SIMONS: So that gets back to what could be causing this. We've heard a lot about how it's not the big concussion or two or three big concussions, but the repeated trauma. Are these even concussions?
STEVEN ERICKSON: We don't know that, either. We don't know if it is related to history, that these individuals had. We don't know the effects of subclinical -- subconcussive blows. The offensive lineman that played for 20 years and every single snap there's a head trauma. We do know when you have a concussion if you don't have complete resolution of all your symptoms and you sustain another concussion, you're more likely to have longer lasting or persistent deficits.
TED SIMONS: We're talking about a concussion compared to getting your bell rung, seeing stars, we've all heard of that. Most of us have had an experience like that along the line. Are those concussions?
STEVEN ERICKSON: The definition of concussion is really a head blow followed by temporary neurologic symptoms. We don't need to evaluate all 22 guys during a high school game after every play, even though they may have all had a mild head trauma. Every head below does not cause a concussion, but every blow that results in headache, dizziness, neurological symptoms, should be investigated and we should hold those athletes out until it's deemed they didn't have a concussion or they have had a complete recovery of their temporary neurological deficits.
TED SIMONS: Some of these athletes whether they're NFL, high school, college, soccer, the headers, the whole nine yards, are some more susceptible than others?
STEVEN ERICKSON: We believe there is. We haven't advanced that far. I hope sometimes in my career somebody's going to ask me that question. And we do a battery of five genetic tests and find out what the likelihood of them going on to have CTE is. We know a couple of the genetic markers, but clearly it's multi-factorial and we don't have all the answers.
TED SIMONS: Is there anything -- are we getting any closer to tests on living subjects? Which would seem to be the gold stone here.
STEVEN ERICKSON: At our center we really look at functional neurological deficits. We look for visual deficits, blurred vision, double vision, and we look for cognitive deficits. We try to make sure in everybody that we're caring for, before we return them to further play, that they have had a complete resolution of all of these potential neurologic deficits.
TED SIMONS: I know you can't say guarantees but do we know that really does make a difference?
STEVEN ERICKSON: Anecdotally we do. Because if you have a head trauma and you -- it goes neglected or undiagnosed and have another trauma, you're more likely to have potentially permanent neurological deficits. When somebody has a complete Resolution, we're not just talking about complete Resolution of their symptoms. We're not asking about concussion, if they are okay, yeah, they're okay and trusting that. We don't think that's good enough. We need to do objective testing of visual, vestibular and cognitive functioning that their brain is completely back to normal.
TED SIMONS: For anyone that has a child playing a sport like football, what do you tell them?
STEVEN ERICKSON: You need to be aware. Make sure all of those individuals have baseline testing. One of the best answers in managing concussion is if we have a snapshot of what their neurologic function is before the injury. As they go through the recovery and we rehabilitate those deficits, that we have achieved complete resolution of all of those symptoms. And to be aware of anybody with a head blow followed by symptoms, should be held out. When in doubt, sit them out.
TED SIMONS: That is it for now. I'm Ted Simons, thank you so much for joining us. You have a great evening.
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Dr. Steven Erickson: MD at Banner Concussion Center in Phoenix