S2 E6: Chronic traumatic encephalopathy (CTE) and it links to participation in contact sports

In this episode of the Pathologists Cut, RCPA President Dr Lawrie Bott catches up with Associate Professor Michael Buckland to discuss chronic traumatic encephalopathy (CTE) and it links to participation in contact sports. They discuss how it manifests pathologically, and what current research tells us about diagnosis and recognition of the condition.

A/Prof Buckland is Head of the Department of Neuropathology at Royal Prince Alfred Hospital. He is the founder and Director of the Australian Sports Brain Bank, Co-Director of the Multiple Sclerosis Australia Brain Bank, and Head of the Molecular Neuropathology Program at the Brain & Mind Centre.  

Transcript

00:00:00:22 - 00:00:17:11

[Voice over]

Welcome to the Pathologists Cut podcast. This RCPA podcast explores the broad medical specialty of pathology and the critical role pathologists play in medicine and health care.

00:00:17:13 - 00:00:47:14

[Dr Lawrie Bott]

Hello and welcome to the RCPA’s Pathologist Cut Podcast series. Today we will be talking to Associate Professor Michael Buckland about chronic traumatic encephalopathy and its links in participation in contact sports such as boxing, AFL, rugby union and Rugby league. Associate Professor Buckland is a senior staff specialist and head of the Department of Neuropathology at the Royal Prince Alfred Hospital.

00:00:47:16 - 00:01:04:11

[Dr Lawrie Bott]

He's also the founder and director of the Australian Sports Brain Bank, co-director of the Multiple Sclerosis Australia Brain Bank and head of the Molecular Neuropathology Program at the Brain and Mind Center. Thank you for joining us, Michael.

00:01:04:13 - 00:01:06:23

[A/Prof Michael Buckland]

Thanks very much for having me, Lawrie.

00:01:07:00 - 00:01:28:00

[Dr Lawrie Bott]

So, Michael, chronic traumatic encephalopathy or CTE, has been in the news recently with a landmark lawsuit brought against the AFL. But players who claim that they've been permanently damaged by concussions or other head knocks. Can you explain what CTE is, what causes it, and why it is linked to certain sports?

00:01:28:02 - 00:02:04:15

[A/Prof Michael Buckland]

Sure. So CTE or as you've said it, chronic traumatic encephalopathy. It's a progressive degenerative brain disease, not that dissimilar to Alzheimer's disease. The way we diagnose CTE at the moment and the way it's defined, it's actually a pathological definition. So the disease is defined by how it looks under the microscope, which is essentially accumulation of abnormally phosphorylated tail around small blood vessels in the depths of cortical sulky and the sulky  are the bellies on the outside of the brain.

00:02:04:17 - 00:02:49:01

[A/Prof Michael Buckland]

It's something actually we've known about for close to a hundred years. But for most of that 100 years, it's something we've always associated with ex boxers. And in the past it's been known as Punch drunk syndrome. These are the clinical manifestations of it, or dementia pugilistica, certainly when I was a medical student, I was taught about dementia. Pugilistica as very rare brain disease that occurred in some boxers and was very much thought of as something that was real but was, you know, an oddity or a rarity restricted to this very small group of the population.

00:02:49:03 - 00:03:41:16

[A/Prof Michael Buckland]

It was really only in 2005 when the first case of CTE was described in a ex-player of professional American football, that the awareness started to grow, that this disease was not just restricted to boxers, but can also be found in people that were exposed to repetitive head impacts from a whole variety of different contact sports and to date, we know it's been described in American football players, ex Australian Rules football as rugby union and rugby league players, boxers and also people that are exposed to repetitive head impacts outside of sport, such as some people that have a very poorly controlled tonic clonic seizures, large numbers of them.

00:03:41:18 - 00:04:11:04

[A/Prof Michael Buckland]

And even in a couple of women that had been exposed to quite severe intimate partner violence. So CTE appears to be a disease that is delayed in onset, in most cases, progressive degenerative brain disease. And almost everyone to date that has been diagnosed with CTE at autopsy has had a history of exposure to many, many repetitive head impacts.

00:04:11:06 - 00:04:19:23

[Dr Lawrie Bott]

Is it only caused by head knocks or could it also be caused by sudden loss of brain momentum due to powerful body contact?

00:04:20:00 - 00:04:53:20

[A/Prof Michael Buckland]

Oh, yeah, that's a really good question. So much like concussion. We know that for most cases, the damage to the brain is caused by a direct blow to the head. You're right in that it doesn't have to be a direct impact to the head. It could be force transmitted from a blow to the body. It's transmitted to the brain or a whiplash type injury where the head moves around violently and the brain is sort of sloshing and twisting about inside the skull.

00:04:53:22 - 00:05:10:00

[A/Prof Michael Buckland]

So you're right, it doesn't have to be a direct hit impact. It can be other ways in which there is a significant amount of force transmitted to the brain, typically acceleration, deceleration force with a rotational component.

00:05:10:02 - 00:05:16:05

[Dr Lawrie Bott]

So what are the clinical symptoms of CTE and how is it diagnosed?

00:05:16:07 - 00:05:45:20

[A/Prof Michael Buckland]

So what we know about the clinical symptoms has predominantly been derived from retrospective interviews with family and friends of people that have been diagnosed with CTE after they had died. So I think there's still quite a lot to learn about that. It seems that CTE can occur in quite young people. I mean, we have seen it and with international colleagues have seen it in people in their twenties and thirties.

00:05:45:22 - 00:06:35:24

[A/Prof Michael Buckland]

But sometimes it only seems to declare itself in people in their sixties or seventies and quite a wide age range where it can impact often with the younger people. So the people under the age of 60, it often manifests initially as symptoms that would overlap with mental health symptoms or post-traumatic stress disorder, in that often people will present with anxiety or depression, impulsivity, aggression, suicidality, drug and alcohol abuse, those sorts of symptoms which are relatively nonspecific, but certainly in the case of CTE, seem to be linked to this degenerative brain disease in the older population.

00:06:36:01 - 00:07:03:15

[A/Prof Michael Buckland]

If the disease comes on in that older population, it often can look a lot like Alzheimer's disease that people start to experience problems with memory and thinking and planning. That is, symptoms are almost always progressive and get worse over time and often the younger people with potentially mostly mental health type symptoms initially as the disease progresses, will then develop.

00:07:03:15 - 00:07:38:06

[A/Prof Michael Buckland]

Also these problems with thinking and planning and memory. So to date, CTE cannot be reliably diagnosed during life. There has been a clinical syndrome proposed called Traumatic Encephalopathy Syndrome, or TES. It was initially proposed in 2014 based on these retrospective interviews with friends and family members. More recently, it's actually been tested against a group of people that ended up dying and having their brains examined.

00:07:38:08 - 00:08:04:20

[A/Prof Michael Buckland]

And it was found that the TES or traumatic encephalopathy syndrome diagnosis is very sensitive in that it picked up almost everyone that ultimately was found to have CTE, but it was not very specific in that it also picked up a whole lot of people that didn't have CTE when their brains were looked at, at autopsy. So if you were given the diagnosis of TES.

00:08:04:22 - 00:08:58:06

[A/Prof Michael Buckland]

S, it looked like you had a 20% chance of having CTE diagnosed at autopsy. So clearly those criteria are not particularly clinically useful at that stage. New criteria have been proposed a refinement of the prior criteria, and they're currently being tested prospectively. So certainly be interesting to see if they are much better or not. I think in the future the diagnosis of CTE in someone that's living, it's going to rely not only on clinical signs and symptoms, but a battery of tests, including CSF analysis, neurophysiological tests, and probably PET scans as well, that those sorts of tests are still in the development phase.

00:08:58:08 - 00:09:01:24

[Dr Lawrie Bott]

So how common is CTE in Australia?

00:09:02:00 - 00:09:32:14

[A/Prof Michael Buckland]

I mean, to be blunt, we have no idea. At this stage as it can only be diagnosed at autopsy. It's very, very hard to get population-based studies based on autopsy data. We have not really been looking for this disease in the past and so what does concern me is that with the Australian Sports Brain Bank, we're obviously collecting brains from people with exposure to repetitive head impacts.

00:09:32:16 - 00:10:01:23

[A/Prof Michael Buckland]

What's slightly disturbing is just in that population how easy it is to find this quite distinctive pathology. And certainly, in the rest of my day job where I do a large number of cranial brain examinations and hospital autopsies, we almost never see it. But in that population exposed to large numbers of head impacts, you know that half our brains will end up showing definitive signs of CTE under the microscope.

00:10:02:00 - 00:10:08:05

[Dr Lawrie Bott]

What is the Australian sports brain bank and how is it helping people with CTE?

00:10:08:07 - 00:10:46:21

[A/Prof Michael Buckland]

So the Australian Sports Brain Bank is a brain bank set up as a research entity. We're very lucky in that we were able to set it up within an existing, dedicated and nata accredited clinical diagnostic neuropathology unit. So while it's a research entity, it still falls under our clinical acreditated diagnostic lab. The idea is that people can sign up during life to donate their brain after death or sometimes family members can reach out when a loved one dies and asks for their brain to be donated.

00:10:46:23 - 00:11:37:13

[A/Prof Michael Buckland]

And so it's entirely based on donations. And we accept donations from people 18 years and older with any history of of any sports participation. And the brain undergoes a comprehensive examination for not only CTE but other diseases. We issue a report and we then store the brain for future research studies, and we hope in the near future that we will have enough material to be able to open up the brain bank so that researchers across Australia can get access to this tissue to try and really turbocharge research into this disease so we can understand it and work out how to diagnose it during life and ultimately how to treat it.

00:11:37:15 - 00:11:39:22

[Dr Lawrie Bott]

Are you getting enough brains?

00:11:39:24 - 00:12:06:05

[A/Prof Michael Buckland]

A good question. That one I've been thinking about a lot lately. I mean, from a simple pathologist's point of view, you can never have enough brains. The more the better. And particularly if we want to start trying to at least incidence in Australia or prevalence, we need big numbers at this stage. We've been averaging just over a brain a week since last Christmas, which is quite busy for us.

00:12:06:07 - 00:12:29:16

[A/Prof Michael Buckland]

We're only a small outfit, so it's pushing us in terms of resources. The ideal solution is that we would get more resources so we can continue to expand that donor program because there's a lot of people out there that I think worry about CTE. And you know, the more that the bigger the numbers we have, the quicker we're going to get answers.

00:12:29:18 - 00:12:39:07

[Dr Lawrie Bott]

Yeah, you mentioned before the proportion of brains that have CTE. Do you want to elaborate on your findings at the moment?

00:12:39:09 - 00:13:08:17

[A/Prof Michael Buckland]

Sure. We published the first 21 brain examinations last year in the Medical Journal of Australia. So that's I guess where our peer reviewed research is up. Two of those first 2112 of the 21 had CTE was the most common brain pathology we identified in that contact sports population. Eight out of 11 of the ex professional players that donated their brains had CTE.

00:13:08:19 - 00:13:35:21

[A/Prof Michael Buckland]

Possibly more disturbing is that half the cases of CTE, both amateur and professionals had died from suicide to date. We've completed the reports now on approximately 52 donations and we have another 20 in the works. This is not yet peer reviewed. But of those 52. We're still sitting at 50% CTE, right? And 50% of those died from suicide.

00:13:35:23 - 00:13:41:16

[Dr Lawrie Bott]

That's suicide rate. It's a truly shocking statistic. Isn't that incredible?

00:13:41:18 - 00:14:13:15

[A/Prof Michael Buckland]

It's something that's hotly debated. Many people will say that there's no good evidence to link CTE and suicidal behavior. Regardless, the observation and the fact it is consistently strong, I agree, is highly disturbing. I don't think so to the general public, understand that if you or your loved one commit suicide, I mean, you are referred to the state coroner for investigation, but in almost all cases, the brain is not examined.

00:14:13:17 - 00:14:21:11

[A/Prof Michael Buckland]

So it does worry me that, you know, what are we missing by not looking at the brains of all these suicide cases?

00:14:21:13 - 00:14:34:03

[Dr Lawrie Bott]

No mean. So how does Australia, compared to other countries in recognizing CTE and what changes do you believe need to be made to contact sports here?

00:14:34:05 - 00:15:09:20

[A/Prof Michael Buckland]

I think Australia has been a bit slow to the party internationally when it comes to recognizing CTE. I have worried in the past that our reputation on the science of CTE on the international stage is actually worse than our reputation on climate science because we have been known to be the bastion of denialism. I think that's changing. And while I've been quite pessimistic in the past, I've actually turned I think I'm optimistic now that although we might have been slow to start, I think we are quite quickly catching up.

00:15:09:22 - 00:15:34:22

[A/Prof Michael Buckland]

I'm still hopeful that, you know, in the near future we could turn it around and be a world leader in addressing the issue of CTE, particularly in contact sports in terms of what needs to we do with contact sports. I think everyone agrees that exercise is good for you. Team sport is good for you. Running around a footy field and kicking a ball with your children is fantastic.

00:15:34:24 - 00:16:03:19

[A/Prof Michael Buckland]

It's just not good to be hit in the head alot and it's not good to allow your children to be hit in the head alot, particularly every week. And so what we need to do is think about how we modify contact sports to reduce overall exposure to these repetitive head impacts or these repeated mild traumatic brain injuries that might be concussion.

00:16:03:21 - 00:16:44:11

[A/Prof Michael Buckland]

But the vast majority of them leave no signs or symptoms. And I think in Australia we have good sun sense now it's taken a generation or two, lots of advertising campaigns and public health campaigns, but everyone today that has lived a long time in Australia understands about a bad exposure to the sun. And the idea is that you should try and manage your exposure, particularly to summer sun and we all even unconsciously modify our behavior and we need to have that same sort of mindset when it comes to contact sports and repeated head impacts.

00:16:44:13 - 00:16:56:03

[A/Prof Michael Buckland]

How do we modify our behavior to reduce our exposure to it while still enjoying all the benefits of sport and of team sport.

00:16:56:05 - 00:17:22:13

[Dr Lawrie Bott]

On this point? And this worries me. I mean, sports administrators undoubtedly have a conflict of interest despite their duty of care to the players, and I think we accept that they want the game to prosper. So do you think sports administrators and or the media with this conflict may be underestimating the potential damage to the brain in these sports?

00:17:22:15 - 00:17:53:08

[A/Prof Michael Buckland]

I don't know. I don't know if they're underestimating or if they're just burying their head in the sand and refusing to acknowledge. It's something I've learned only since working with the brain bank, just this quite unusual place that sporting bodies occupy in our society. They're almost like the Catholic Church in that they enjoy a very exalted status, including tax free status.

00:17:53:10 - 00:18:31:13

[A/Prof Michael Buckland]

And that may be historically in the church, but certainly sporting bodies today, that the amount of regulation and scrutiny that they undergo from governmental organizations is relatively lax. They're almost like a law unto themselves. And I think that needs to change. I think that this is a public health issue and potentially a very large public health issue, and it is time to take the management of that issue out of the hands of sporting organizations and into the hands of public health professionals and governments.

00:18:31:15 - 00:19:03:10

[Dr Lawrie Bott]

Being an ex rugby player myself, I am. I can see the rules of the game may need to be changed significantly, even to the point that it slightly changes the nature of the game, perhaps the statistics of past games, etc.. What are your thoughts on these? Do you think that in fact there may need to be significant real changes to achieve safety for, as you say, children, you know, young people in the community.

00:19:03:12 - 00:19:27:20

[A/Prof Michael Buckland]

When it comes to children? It does. And I think I very strongly believe that children should be playing either low contact or no contact versions of the game, at least until they're in high school. I think we have a duty of care to the next generation to look after their developing brains. I think that needs to be instituted as a matter of urgency as far as I can see.

00:19:27:22 - 00:19:57:01

[A/Prof Michael Buckland]

When it comes to the adult games, we all do things that may be risky for our health. We're not about turning into a nanny state or taking out all the risk in life, but with most things that you do where you're taking a risk, you are actually well informed about the risk. I think the fundamental issue with contact sports is that I feel that no one is really well informed of the risks they're taking.

00:19:57:03 - 00:20:20:04

[A/Prof Michael Buckland]

And so, yes, I think there does need to be changes to the rules. Alongside that, I think there needs to be a concerted education campaign about just what the risks are, just like with smoking, you know, and it may well take a generation to really make those changes stick. But yes, I think there's two things is changing the rules.

00:20:20:06 - 00:20:49:18

[A/Prof Michael Buckland]

And also educating people and taking that information that the sporting codes are not the guardians of that information and sporting doctors are not the experts that should be providing that education. If I had a ruptured ACL or a sore shoulder, I would immediately go to a sports doctor. If we're talking about the degenerative brain diseases, that is not their area of expertise, and particularly ones where the pathology is the defining factor.

00:20:49:20 - 00:20:58:07

[A/Prof Michael Buckland]

That is the role of pathologists, public health professionals working with neurologists. They're the ones that should be taking the lead on this.

00:20:58:09 - 00:21:19:17

[Dr Lawrie Bott]

I mean, is it fair to say that the good work that you're doing and through the sports brain bank, that you are creating the evidence that people are allowed to change the rules, protect people, but also make decisions, risk decisions on what they are willing to undertake or not?

00:21:19:19 - 00:21:58:08

[A/Prof Michael Buckland]

Yes, I think so. You have to gather the evidence by identifying this disease in Australia. I think the brain bank has already changed the narrative in Australia quite significantly and I see that as a very important role moving forward as well, gathering the evidence. It's funny, isn't it? Because I mean, Laurie, you probably like me that, I mean, most pathologists don't go into pathology to change public opinion, but it's just a situation where the brain bank have found ourselves inthat we have a powerful voice in driving the public debate on this issue as well.

00:21:58:10 - 00:22:03:14

[A/Prof Michael Buckland]

So, yes, yes, it's been it's been an interesting journey.

00:22:03:16 - 00:22:18:04

[Dr Lawrie Bott]

I also note at times that when there has been a concussion, players have gone back into the game relatively quickly. If you the comments on the risk period after a concussion.

00:22:18:06 - 00:23:00:23

[A/Prof Michael Buckland]

It is a contentious matter. There's always lots of debate. I'm not an expert in management of concussion, but what I can tell you is that although it's not voluminous, there is a body of pathology literature on the pathology of concussion stretching back 50 years, and it is consistently pointing to structural damage to the brain in episodes of concussion with evidence of external injury and microvascular injury and the false narrative that has been pushed recently about concussion.

00:23:01:02 - 00:23:20:20

[A/Prof Michael Buckland]

Just being a functional injury is actually incorrect. And pathologists have been showing that for 50 years with a structural injury to the brain. I don't think anyone would argue that would take a significant amount of time to heal. I mean, I guess that's that's what I can add to that debate.

00:23:20:22 - 00:23:29:17

[Dr Lawrie Bott]

Thanks, Michael. But there are international guidelines to reduce the causes of CTE.

00:23:29:19 - 00:23:55:09

[A/Prof Michael Buckland]

There's not at the moment. And it's a good question because we're actually talking about that with our international colleagues. There are guidelines on concussion diagnosis and management. But what we're talking about with CTE, it's not just the concussions that are the problem. It's all the other head impacts or micro structural damage to the brain through forces that don't give you concussion.

00:23:55:11 - 00:24:27:01

[A/Prof Michael Buckland]

So we really do need separate guidelines on CTE, risk minimization. And I think my international colleagues would agree that those guidelines should be based on two fundamental principles. And the first one being reducing your cumulative lifetime exposure to these repetitive head impacts. And the second one is delaying the age of onset first exposure to these repetitive impacts.

00:24:27:03 - 00:24:35:08

[A/Prof Michael Buckland]

So I think those two principles are fundamental to any future CTE minimization policy.

00:24:35:10 - 00:25:03:22

[Dr Lawrie Bott]

I think that's great. Michael, many thanks for talking with us today. But from my medical interest, as I said before, as an ex rugby player, I have another perspective. So it's very topical and now understanding is clearly evolving. I congratulate you on the work that you've done in this area. Thank you again for enlightening us today. Thank you.

00:25:03:24 - 00:25:09:10

[A/Prof Michael Buckland]

Thanks very much, Lawrie. Thanks a lot for your interest.

00:25:09:12 - 00:25:24:18

[Voice over]

You have been listening to the pathologist's podcast with RCPA President Dr. Lawrie Bott, to learn more about pathology. Check us out on Facebook, Instagram and Twitter.