What Do We Know About How Many People Might Have CTE
0 (0 Likes / 0 Dislikes)
Prevalence is a very difficult study to perform
when we don’t have a diagnostic marker during
life.
I think once we have that diagnostic marker
we’ll be able to do prevalence studies fairly
easily.
But at this point we can only make the diagnosis after death.
So for us to do a really well-composed prevalence study, we’d have to get two groups with
different exposures to football and follow
them till death some 60 years and then look
at the rates of CTE in their brain after death.
So nobody has 60, 70 years to wait until this
answer.
So what we have is a convenience sample.
It’s a brain bank sample.
It does have selection bias in it.
There’s no question.
But all brain bank studies have selection
bias.
It’s important to know that in our brain
bank, the criteria for admission to the brain
bank is based on exposure to head injury.
We don’t look for symptoms.
We don’t look for anything else.
It’s just whether or not they were exposed
to head injury.
That’s not true for any other brain bank
that I know of.
This is a unique brain bank.
In all of those other brain banks, CTE is
very rare.
The ones that don’t recruit for head injury.
But in our brain bank, it’s very high.
In fact, in our JAMA study that came out last
July it was 87% for all American football
players over an eight-year period, which is
quite high.
Now, a lot of what I would say people that
don’t want to accept CTE as a real public
health issue.
They have pointed to that selection bias as
a reason to discredit the study, a reason
to just ignore the study altogether.
And I think that’s quite ridiculous.
First of all, we do have selection bias.
But the people that ask for the brain to be
examined, because 90% of our brains come from
the families of the person, not from a doctor
or from a medical examiner.
They come from the families.
Those people are ordinary citizens.
They’re not specifically trained as diagnosticians.
They don’t have a tertiary medical center
in their back pocket.
They haven’t done all sorts of fancy tests.
These are just people that have seen the symptoms,
thought something was unusual usually, and
had a hunch that something was going on.
And they referred the brain in for us to analyze it.
And so that hunch is 87% correct.
That’s remarkable.
So that just wouldn’t happen unless this
is a real problem.
We don’t know the degree of that public
health problem, but it’s certainly an issue.
And if we look at the denominator just in
NFL players because we had 111 NFL players
in that study.
If we took all the NFL players that died during
an eight-year period that were included, if
we assume that every other NFL player that
died somewhere else that didn’t donate their
brain to science did not have CTE, which would be a very absurd assumption.
The minimum rate of NFL players being affected is 10%.
That’s the least it could possibly be.
And so you have to ask yourself: is that an
acceptable occupational hazard that 10% of
you are gonna develop an untreatable, progressive neurodegenerative disease.
So, in my mind that’s clear evidence that
this is an issue.
And then there were a lot of amateur players
in that study.
91% of the college players, 21% of the high
school players were diagnosed with CTE.
So this isn’t just something that happens
to the extreme and extraordinarily gifted
football players.
This is something that happens to amateurs.
This video was produced by BrainLine
thanks to generous support from the Infinite Hero Foundation.