Decoding Chronic Traumatic Encephalopathy
Dr. Lee Goldstein explains what exactly this bonafide brain disease is as well as the rogue protein, tau, and how trauma is associated.
This is a disorder that is a bona fide neurodegenerative disease. It's progressive and it unfolds over a period of years. So the words really tell you what it is in some ways once you decode it. It's chronic, meaning that it lasts a long time. And in fact, our evidence suggests that it's progressive. That means it gets worse with time. We also know that in all cases that we're aware of, this disorder is linked or associated with brain trauma. So there is some inciting injury or multiple injuries that then lead to a neurodegenerative disease that follows secondarily. So the way we think about this is there's an initial trauma that can damage the brain directly, and there can be injury and deficits and problems associated with that, both clinically and at the level of the brain. And then over years to decades there's a secondary process that appears to unfold called chronic traumatic encephalopathy, which is really a connected but a second disorder. And as a neurodegenerative disease, it has features that are like many of the other age-related neurodegenerative diseases, like Alzheimer's disease is another one, some frontotemporal dementias, Parkinson's disease is another one. They unfold over years, and the deficits to the individuals, their families, their ability to be in the world unfolds over that time and the impairments become greater over time. And again, this is years to decades. And the last piece of it--there's the chronic, there's the traumatic-- is the encephalopathy. Encephalopathy means the brain is not right. And in fact, that is true and we have a pretty good understanding now about how it's not right. Part of it has to do with this protein called tau, and we know that in both chronic traumatic encephalopathy and its variants that tau becomes deranged, and this rogue protein causes problems throughout the brain and in fact leads to loss of brain cells and particularly neurons, and those are the primary cells of the brain that are involved in thinking and memory and what we think of when we think of the brain. So that becomes deranged with time. That's the encephalopathy part. So this is a bona fide brain disease, and the linkage to trauma, that's something that we're working out now. But certainly we know that repetitive trauma and high contact sports like football or hockey or boxing lead to this disorder in some subset of individuals-- we don't know how many. In some set of individuals we see that this disease is linked. And now what we've recently found is that other traumas, including exposure to blast, may also be associated.
Posted on BrainLine February 28, 2013.
Dr. Lee Goldstein is an associate professor of Psychiatry, Neurology, Ophthalmology, Pathology and Laboratory Medicine, and Biomedical Engineering at the Alzheimer's Disease Center at Boston University.
Produced by Brian King, Vicky Youcha, and Erica Queen, BrainLine.