GUY RAZ, HOST:
And if you're just tuning in, this is WEEKENDS on ALL THINGS CONSIDERED from NPR News. I'm Guy Raz.
Here's a terrible statistic: Once a veteran is home from Iraq or Afghanistan, he or she is more likely to die by suicide than from injuries sustained in the combat theater. There is new research that suggests those injuries may actually be contributing to the suicides.
Now, scientists have known for years that athletes like boxers and pro football players are prone to developing a degenerative brain disease called chronic traumatic encephalopathy or CTE. It's triggered by repeated blows to the head, and it can cause memory loss and mood changes and impulsive behavior. The problem, though, is that CTE cannot be diagnosed in a living person. The signs are often found in the brain during an autopsy. And now, CTE has begun to appear in the brains of veterans.
Researchers are wondering whether CTE could be related to traumatic brain injury, another mysterious injury that many veterans have sustained. Robert Stern is a professor of neurology at the Boston University School of Medicine, and he's been looking into that very question.
ROBERT STERN: Traumatic brain injury is the big event, whereas CTE is a disease. It's not an injury. It gets started in motion earlier from repetitive exposure to mild brain injuries.
RAZ: It's triggered by injuries.
STERN: Trigged by it, that's right. But it's not an injury in and of itself.
RAZ: So there's no way to tell if somebody is affected by CTE through a brain scan. You can't determine that just by doing an MRI.
STERN: Well, we're trying to right now. I was very fortunate in getting a grant from the National Institutes of Health recently to do just that. And to me, that's really the big next step. We really have a good understanding of the neuropathology of this disease, what it looks like after people die. But now, we really need to move this field forward by being able to diagnose people while they're alive so we can understand how common it is, so we can understand what the risk factors are, so we can understand how to treat it and prevent it.
RAZ: What is the thinking about the possible connection between CTE and suicide? I mean, we know that suicide rates among returning Iraq and Afghan vets, those rates are higher compared to Vietnam vets. Is there any developing theory about the relationship between CTE and suicide?
Well, we have a pretty good sense in athletes, not vets, that suicide is a common problem within a group of athletes who develop CTE. Now, we need to think about it in returning veterans, where there is so much suicide, and they also have such a huge exposure to brain trauma.
STERN: There's this fuzzy line between the symptoms of traumatic brain injury, posttraumatic stress disorder and CTE, where they all can have difficulties with thinking and memory, with mood and with behavior change. And we just don't know yet how much of the suicide problem is caused by just natural grief responses or psychological effects of being in such brutal conditions or how much is due to PTSD or the long-term effects of an individual brain injury or perhaps to CTE. My hunch is that some of the suicides that have already occurred are due, at least in part, to the disease CTE.
RAZ: That's Robert Stern. He is a professor of neurology and the co-director of the Center for the Study of Traumatic Encephalopathy at the Boston University School of Medicine. Professor Stern, thank you so much.
Thank you very much, Guy. Transcript provided by NPR, Copyright National Public Radio.