A new study led by Boston University researchers shows that there could be progress when it comes to diagnosing the brain disease CTE, chronic traumatic encephalopathy, in living patients. Lead author Dr. Robert Stern of Boston University spoke with WGBH All Things Considered anchor Barbara Howard about the study, which was released this weekin the New England Journal of Medicine. This transcript has been edited for clarity.

Barbara Howard: Explain why this study that you did is important.

Dr. Robert Stern: Well for us to understand some really important issues about CTE, like, How common is it? Why do some people get it and some people don't? What are the risk factors? — we need to be able to start diagnosing people during life, so we can study large numbers of people. I'm pretty confident that we're going to be able to detect and diagnose CTE during life in around five years or so. The great thing is that we can piggyback on the advances that have been made in Alzheimer's disease diagnoses for our new attempts to diagnose CTE during life.

Howard: That sounds like that's what you did with this study. As I understand it, you took a group of 26 former NFL players around the ages of 40 to 70, roughly, exhibiting signs of CTE, which can mimic Alzheimer's, and you took a control group of people with no history of head trauma, and conducted two different scans on these two groups looking for two different things. They were looking for a tangle of what's known as tau, and tau is found in the brains of those suffering from both Alzheimer's disease and CTE. But that second scan looked for amyloid plaques. Now amyloid plaques are common in Alzheimer's, but not in those who suffer from CTE. What did you find from this?

Stern: We found that these experimental PET scans that measure this abnormal protein, tau, were able to detect elevated levels of this protein in the former NFL players.

Howard: More so than the controls?

Stern: More than the controls. And it was found in the same places in the brain that we would expect it to be based on the post-mortem studies of CTE.

Howard: And the highest level of tau were those who had played football the longest?

Stern: You know, we found a direct relationship between the amount of tau and the number of years people played tackle football.

Howard: So it's this tangle known as tau that you're looking for. How about the amyloid plaques? Those are associated more with Alzheimer's. Did you find that in the football players?

Stern: We didn't. We found no significant differences between the groups with the amyloid PET scan. So what it told us was that the symptoms that these guys were having were unlikely to be due to Alzheimer's disease.

Howard: Does your study have any implication for the treatment of CTE? Are there any signs of hope there?

Stern: Well what's really wonderful is that these new advances in our ability to detect these abnormal proteins during life is going in a parallel type of fashion as the new medications to hopefully stop the proteins from developing, or slowing them down so they don't destroy too much brain tissue.

Howard: It sounds like a lot of what you're doing is a little, too little too late. You're catching people who are already afflicted. How is this really helpful?

Stern: Well all these brain diseases seem to be progressive. They start in very small parts of the brain, and then they spread and spread. And as they spread, they destroy more and more of the brain. If we can intervene early, before the destruction of the brain tissue, then we may be able to prevent the symptoms from ever starting in the first place.

Howard: Is there a way to use these tests in terms of finding a kid who's maybe into football, but is at risk? Is there a way to diagnose that you're at risk for problems down the line when you're older? Something that schools, for example, might adopt in terms of who is allowed to play these sports?

Stern: Well you know, I can't even get there yet. We can't translate our science into policy at this point.

Howard: Would you like to?

Stern: You know for me, I study these individuals later in life who have so much destruction of their life. They're so devastated. I want to make sure that people don't get to that point. One of the things that I'm finally really coming to terms with as a reformed football fan is that we shouldn't be putting our kids on a field during a time when their brains are going through this incredible amount of development, and put a helmet on them and say, 'Go slosh your brain over and over again.' It just doesn't make sense to me.

Howard: That's Dr. Robert Stern of Boston University's CTE Center. He led a research team that's released a study this week in the New England Journal of Medicine that's made strides in the diagnosis of CTE in living patients.