Dr. Ann McKee on the Range of Severity with CTE
Our studies show that CTE is a progressive
disease. So we do have four stages of severity of pathology
with one being the mildest and four being the most severe. We definitely generally see the milder stages
in the younger athletes. It takes time for the disease to become full-blown
and very severe. So it’s the older players that played more
years that generally get the more severe CTE. But disturbingly, and for reasons we don’t
understand because the tau pathology is very focal in the mild CTE cases. They can often be very, very asymptomatic. And I think that’s what’s – people like
Junior Seau, he had relatively mild CTE, but you know he had a lot of behavioral problems. He was out of control, and eventually ended
up committing suicide. Very asymptomatic, very erratic behaviors,
very different than he had been previously, low-level CTE, mild CTE. But we’ve seen that in college players,
too. We’ve got so many examples I don’t know
where to begin. But we see suicidality, impulsivity, depression,
erratic behaviors, lack of self-control in these young athletes with low-level CTE. When we get into the higher states we start
to see memory loss and real impairment with activities of daily living, but I think if
you follow this field at all, you’ve seen many examples of people very affected even
at mild stages. And then there’s also the fact that the
more we study this disease, the more it is apparent that this is a progressive disease. It starts from trauma, trauma’s effect on
the nervous system. There’s this acceleration/deceleration injury,
the rotation that stretches the brain, it stretches the intrinsic components of the
brain. It injures nerve cells. Those nerve cells accumulate tau. We think initially that that tau may be reversible. That may be initially a reparable lesion. But eventually, with enough hits, with enough
damage, it triggers a progressive decline. So there’s a point where it becomes a progressive
disease even if the person stops playing football, if they give up all exposure to trauma. The disease continues to progress, and so
even though it’s triggered by trauma, at some point it becomes trauma-independent. And so that’s the real danger. So even if you’ve got someone young with
mild CTE, most of our evidence at this point shows, points to the fact that it’s gonna
get worse as they survive. This video was produced by BrainLine thanks to generous support from the Infinite Hero Foundation.
Posted on BrainLine January 11, 2019.
Ann McKee, MD is the chief neuropathologist for the Framingham Heart Study and the Boston University-based Centenarian Study. She is also the chief neuropathologist for the Boston-based Veterans Administration Medical Centers and for the Sports Legacy Institute.
