Scientists can now predict with reasonable certainty who is likely to get Alzheimer's, the incurable brain disease that afflicts more than 5 million Americans. But that means many of us will have a difficult decision to make: should we be tested when there is currently no effective treatment? The answer to that question could determine the progress of Alzheimer's research.
A Parent's Rapid Decline
It was about four years ago when Elaine Marasca's family began to notice that she didn't seem quite right. She couldn't remember her Social Security number. She struggled to find the right words. Her daughter Kristyn, who's now 28, noticed something else.
"One time I came over for dinner and she had made pasta and she forgot the sauce, and she put it out on the table and I said, 'Where's the sauce?' " Kristyn recalls. "And she said, 'Oh my God, I forgot it. I'll go to the store right now and buy it.' So it was little things like that that you kind of thought, 'Well, that's strange. She would never do that.' "
Elaine's 32-year-old son, Dennis, picked up another thing.
"She would say she was going to write a lot of stuff down," he says. "Like, I told her I got a promotion at work and a raise and she'd say, 'Oh, I'll write that down.' Or we got a new cable system and she'd say, 'Can you write down how to turn the TV on?' And I thought it was just, well, we got a new remote and no one knows how to use it. Stuff like that."
It turned out that, although she was only 53, Elaine had early-onset Alzheimer's, which accounts for about 5 percent of all cases. Her decline was rapid. Now, at age 56, she lives in a nursing home and her conversations are limited to one or two words. For her children, it's been like losing a parent.
The Early-Testing Push
But their mother's illness makes the Marasca kids of great interest to researchers like Dr. Reisa Sperling, who directs the Center for Alzheimer Research and Treatment at Brigham and Women's Hospital.
"We have tools that can now pretty accurately detect the presence of Alzheimer's disease beginning in the brain," says Sperling, who, along with other researchers, wants to identify and test people like the Marasca children even before they may have any Alzheimer's symptoms.
The thinking is that once someone is diagnosed with Alzheimer's, too much brain damage has occurred to be reversed. But if they can treat people in the initial, invisible stages of the disease, they may be able to halt or delay the damage.
"I believe this is the way we will find a treatment," Sperling says. "We must identify people at risk to be able to decrease their risk of going on to develop dementia. This is absolutely what we must do."
Diagnostic exams like spinal taps and PET scans can now look inside a human brain and identify the presence of amyloid. That's the telltale plaque that destroys brain function in Alzheimer's sufferers. In the case of brain PET scans, patients are injected with a radioactive substance that during imaging will show whether there is amyloid in the brain, a possible indication of Alzheimer's disease.
The hope is to get these subjects into experimental drug trials aimed at stopping or slowing the disease process. But that means that patients who may not have any symptoms might learn whether they're likely to get a fatal disease for which there's now no effective treatment. And that makes the to-test-or-not-to-test question a potentially wrenching one.
For now, however, once they're tested, research subjects are not informed if there's amyloid in their brains or if they have a genetic proclivity for the disease. That's because researchers fear that informing the subjects might bias the research — for example, a patient told he has amyloid might begin to attribute every forgetful moment to a possible developing disease — and also because researchers don't yet fully know the implications of their findings. In future studies, research subjects may also be given the option not to be told their test results.
'I'd Rather Be Naïve'
Alzheimer’s researcher Reisa Sperling says that for research to progress, healthy people must be willing to be tested.
Elaine Marasca's children, Kristyn and Dennis, have decided what they would do.
"To me, it would seem like a death sentence hanging over your head," Dennis says. "I would think about it every day. You know, 'Is it going to start now?' Any time I misplaced my keys I'd be like, 'Is that just me being forgetful, or is it an indication of something else?' I think your mind has a tendency to wander and always go down that worst-case scenario."
"I would not deal well with that news, I don't think," agrees Kristyn. "I would rather just live my life the normal way and if it happens, it happens. I'd rather be naïve and not know about it and just enjoy my life than try to do all these things because one day I might get it."
Dennis says if there were a medication he could take to prevent getting Alzheimer's, or if there were proven lifestyle changes he could make to ward off the disease, he might consider getting tested.
"Like, if you're at risk for heart disease, OK, you've got to watch your diet and exercise more," he says. "If there were some guidelines to follow than may help mitigate some of the symptoms, I would."
But while there is no known cure or way to prevent the disease, those who do choose to be tested might benefit from participating in experimental drug trials, with their accompanying risk of serious side effects.
"It's very important to get this disease diagnosed early," says Jim Wessler, president of the Massachusetts/New Hampshire chapter of the Alzheimer's Association. "There are a number of clinical trials, particularly here in Massachusetts, which is very rich in Alzheimer's research. So being diagnosed earlier gives you the opportunity to potentially volunteer for those clinical trials and potentially even benefit from some of the emerging science that's happening."
[sidebar title="By The Numbers: Alzheimer's In America" width="360" align="right"]
- 5.4 million Americans have Alzheimer's
- Alzheimer's is the U.S.' sixth leading cause of death
- Alzheimer's care costs $183 billion annually...
- ...by 2050, the cost is expected to be $1.1 trillion
- Nearly 1 in 8 Americans over 65 will get the disease...
- ...by age 85, nearly 1 in 2 will get the disease
That's a reason many people give for wanting to be tested, despite the heavy burden of possibly learning they may get this life-altering disease. On the other hand, some drug trial participants are likely to be given placebos that won't help them stave off the illness.
Still, Wessler says diagnosing Alzheimer's early also offers the chance to make future plans and live your life to the fullest in the time you have left.
"We talk euphemistically about the bucket list," he says, "but if you have a plan to go visit your grandchildren out in California or to take a trip somewhere, now is the time to do it if in fact you are in the very early part of the disease."
So science has brought us to the point where we can find out if we're likely to develop the disease, but without the promise of successful treatments. That makes for a complicated dilemma for those debating whether to get tested: if you take the test, you might learn you're likely to get Alzheimer's, although you could possibly benefit from experimental treatments.
Or you could simply decline to be tested. In that case, you might risk losing out on the possible benefits that future treatments could provide.
Alzheimer's researcher Sperling says that for research to progress, healthy people must be willing to be tested. She hopes a sense of altruism, of wanting to help future generations of Alzheimer's victims, may push the reluctant to participate.
"Many patients come into trials because they or their family members really hope it will help them," she says. "But they're also extremely motivated to say, 'I want to do something to help this disease.' Or, even if doesn't help them, to help their children."
And researchers, as well as families affected by Alzheimer's, hope that, eventually, people can be tested for the disease with the comfort of knowing that there's a cure or a way to prevent it.
This program aired on October 19, 2011.