MELISSA BLOCK, Host:
From NPR News, this is ALL THINGS CONSIDERED. I'm Melissa Block continuing our discussion of Alzheimer's disease now, with a focus on how the disease progresses and hopes for treatment.
Dr. Marilyn Albert has been listening to Tom and Joyce DeBaggio. She is co-director of the Alzheimer's Disease Research Center at Johns Hopkins University. Welcome.
D: Pleased to be here.
BLOCK: Dr. Albert, when you listen to Tom and Joyce talk about where Tom is, what do you hear? Where is he in the course of his disease?
D: He's pretty advanced. I guess in terms of our thinking of stages, he's well into the next-to-the-last stage of the disease, because you see how much difficulty he has functioning on a daily basis, how much help he needs and how much trouble he has expressing himself, and as you've already seen, this is a gradually progressive disease and over time, more and more abilities get lost.
BLOCK: At the same time, there is so much, clearly, that's getting through to him. When he responded to the reading, there's a lot you can tell inside that he's struggling to communicate, even if he's not able to communicate it.
D: One of the remarkable things about the disease, I think, is that in so many people, their personalities are well preserved. Who they are really seems to remain intact until very late. That isn't true for other diseases of the brain, but that tends to be true for Alzheimer's disease.
BLOCK: We heard Joyce say that the anger is gone, that in earlier stages, Tom would have outbursts, huge outbursts of emotion.
D: I think one of the saving graces in the disease, if you can call it that, is that what happens is a lack of awareness progresses over time. So the part of the brain that enables us to sort of look at ourselves and have a judgment about how we are in relation to the rest of the world begins to be damaged, and so that ability to have self-awareness and insight is lost and in some ways that I think helps the patients to live with the problems that they have on a daily basis.
BLOCK: Is it a common thing when you talk to Alzheimer's patients to hear them be aware, as Tom clearly is, of what he's lost?
D: It's actually less common than you would think. It's more common in people like Tom, who got the disease young. So what I've observed just from looking at patients is that people who get the disease very young have much more awareness in the beginning, and then they lose that over time, and older people, some of them have that awareness, but many of them don't.
BLOCK: When you look demographically at what's happening with Alzheimer's disease, we mentioned it's estimated more than five million people have it now, what are the projections of how that number will grow?
D: The projections are that by 2050 there might be 16 million people.
BLOCK: These numbers are for this country, when we talk about five million people, 16 million people.
D: That's correct. That's correct, yes. The reason that the disease is expected to rise in number is because it's a disease that's related to age, and the most common form of Alzheimer's disease is the most common among people over 85, and that's the segment of the population that's growing most rapidly. So that's why we see these huge projections in numbers, and I think that's why we all feel that if we don't find really effective treatments, it's going to break the back of the healthcare industry. These are people who, as you can hear, are completely dependent on care from other individuals.
BLOCK: What seems to show the most potential for treating Alzheimer's?
D: Right now there are five treatments on the market. None of them are particularly good. They all make people about six months better than they would be without the treatments, on average, but they don't, as you see in Tom, they don't prevent the progression of the disease.
What people are hoping is that we would find medications that would really change the course of disease, so it would keep people at a much milder stage for a long time. Right now there are nine medications that are being tested. A lot of us have enormous optimism that one of these nine are going to be really effective, and the reason we're optimistic is that we understand much more about the basic causes of the disease, and this new group of medicines is aimed more directly at those basic causes.
BLOCK: I thought the causes were a real mystery still.
D: We have hypotheses. So the medicines that are on the market right now affect the chemistry of the brain, and we now realize that's not the primary cause of the disease. We know that much. We know what is happening in the earliest stages of the disease in the brain. There are two different kinds of changes. One is the formation of something we call an amyloid plaque. The other is something we call a tangle, and it's the formation of those two things that destroy the nerve cells.
The medications that people are trying to develop are aimed at the amyloid and the tau in the plaque, and that's why people are more optimistic, because they think if they can change the way those substances are formed or cleared from the brain, they will actually change the way the disease is functioning.
BLOCK: There has been a lot of hope around the possibility of a vaccine for Alzheimer's disease. Where are we with that?
D: That's correct. It's aimed at the substance I mentioned, called amyloid. The notion is that if you give a vaccine, you can either get the brain to mount a response to amyloid, or you can give that in a vaccine, so that either way the brain is forming antibodies to this substance that is accumulating.
And what we know from animal models is that that vaccine clears amyloid from the brain. The vaccine is being tried, and we're learning more and more about how it functions, and hopefully it will be safe and effective.
BLOCK: Dr. Albert, when you think back on the eight years that it's been now since Tom DeBaggio was diagnosed, how much better do you think we understand Alzheimer's disease now than we did then?
D: I think we understand Alzheimer's disease much better now. We know much more about its course. We feel more certain about what the first symptoms are and how they evolve. We're learning more about early diagnosis, because of course the goal would be when we have really effective treatments, we would want to intervene as early as possible. The amount of progress that's been made in the last 25 years is really staggering, and it's because there's been such an emphasis on the disease, and with so many great people working together, I think is why we've made so much progress.
BLOCK: Dr. Albert, thanks for coming in.
D: My pleasure.
BLOCK: Dr. Marilyn Albert is professor of neurology at Johns Hopkins University and co-director of the Alzheimer's Disease Research Center there. You can hear our previous interviews with Tom DeBaggio and read excerpts from his books on life with Alzheimer's at npr.org. You'll also find resources for family members and caregivers for people with the disease.