TOUGH TESTS: Why get screened for Alzheimer’s when there is no cure?

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As a hospice care nurse, Linda Janke has spent the past dozen years witnessing the intense emotional and physical toll Alzheimer’s disease can take.

Now Janke is witnessing the effects of Alzheimer’s closer to home: Her mother, 79, has been clinically diagnosed with the progressive, incurable, memory-stealing disease.

Statistically, having a mother with Alzheimer’s puts Janke at significantly higher risk of someday developing the disease herself. In fact, a test available just this year can tell Janke right now, long before possible symptoms even have had a chance to appear, whether proteins that are associated with Alzheimer’s disease are present in her brain. And that poses an intriguing, but emotionally wrenching, question for Janke to consider.

Does she want to know now whether she will be likely to develop Alzheimer’s someday, given that there’s nothing she could do about it anyway?

“You go back and forth,” Janke says.

Even now, and having nothing more than the knowledge that her mother’s Alzheimer’s puts her at greater risk, Janke admits that with the occasional momentary forgetting of a name, “my first thought is, ‘Is this a sign?’ ”

“I’m in my 50s, and some people develop it earlier than others. But you also know that a lot of (people) have a long time before anybody recognizes it.”

TEST ACCURACY IMPROVES

Dr. Upinder Singh, an internal medicine physician and geriatrician with Touro University Nevada College of Osteopathic Medicine, notes that a definitive diagnosis of Alzheimer’s can be made only after death, when an autopsy reveals the presence of Alzheimer’s-related protein deposits called amyloid plaque in the brain.

Of course, waiting for an autopsy to confirm a diagnosis of Alzheimer’s “is not a good answer,” Singh says. “We need to diagnose it while a person is alive so we can do something for the person.”

So, physicians make a diagnosis of Alzheimer’s disease on the basis of medical and family histories, physical exams, metabolic tests and blood tests, examination of cerebrospinal fluid for proteins associated with Alzheimer’s, evaluations of a patient’s mental acuity, and CT or MRI scans that can detect physiological or functional changes in the brain that might be associated with Alzheimer’s.

Dr. Eric Farbman, assistant director of the University of Nevada School of Medicine’s movement disorders clinic, notes that such tests can be useful not just in arriving at a diagnosis of Alzheimer’s, but, just as important, in ruling out other conditions that can cause symptoms similar to those of Alzheimer’s.

The latest advance in Alzheimer’s diagnosis came this year, when the U.S. Food and Drug Administration gave its approval to a radioactive dye that can be used to determine whether the protein of Alzheimer’s disease is accumulating in the brain, says Dr. Jeffrey Cummings, a neurologist and researcher and director of the Cleveland Clinic Lou Ruvo Center for Brain Health.

The radioactive dye binds to amyloid plaque that accumulates in the brain of a person with Alzheimer’s. Then, a PET scan is conducted, and the presence, or absence, of the plaque is revealed.

Because amyloid plaque can appear in the brain a decade or more before symptoms of Alzheimer’s appear, Cummings says, the new test represents a leap forward in Alzheimer’s research.

“We can begin, for example, to plan (clinical) trials where a person is cognitively normal, but the scan shows the brain is already abnormal,” he says.

“So, it allows us to do a whole different kind of trial in much earlier situations than we have done before. That’s quite a strong advance in our field.”

The new test also offers physicians a more precise tool for diagnosing patients who show symptoms of Alzheimer’s. If no amyloid plaque is found, Alzheimer’s can be ruled out as a cause, even though another dementia-related disease might be present.

Being able to rule out Alzheimer’s is vital in patient treatment. Cummings says one recent older patient who showed symptoms of Alzheimer’s received the scan, and no amyloid deposits were found.

“That was extremely helpful in our diagnosing him with frontotemporal dementia, which usually doesn’t begin so late in life but did with him,” Cummings says. “Alzheimer’s drugs tend to make that group (of diseases) worse. So it has real meaning.”

In patients who are displaying signs of cognitive impairment and in whom the scan does reveal amyloid plaque, treatment and management of Alzheimer’s can begin earlier in an effort to slow the disease’s progression.

Early intervention is important, Cummings adds.

“The data may not be as definitive as we like, but the data in general support the idea that early treatment has long-term benefit.”

NOT FOR CURIOSITY’S SAKE

The new test also lends itself, at least theoretically, to another use: the pre-emptive screening of people who, by virtue of having a parent or sibling with Alzheimer’s, fear that they might someday develop it and wish to find out for sure.

That, physicians say, is where things get tricky.

It is not the first time that an Alzheimer’s diagnostic test has offered that sort of curiosity-sating possibility. For example, Cummings notes that about 60 percent of those with Alzheimer’s “have a family history, which means that another relative closely related to them – either a parent or sibling – has the disease.”

In those patients, “we can do a blood test, which tells people whether they have a genetic risk of Alzheimer’s disease,” he says. “However, we tend not to recommend that because you can have the gene and not get the disease, and, in some cases, you could not have the gene and still get the disease.”

If a genetic association does exist, the lifetime risk of developing Alzheimer’s symptoms “goes from 15 percent to around 30 or 40 percent,” Cummings adds. “So it’s a big jump, but most people who have the gene don’t get it.”

The new amyloid scan is “more predictive” than the genetic test, Cummings says. (And, he adds, people who do have a genetic propensity toward Alzheimer’s are generally more likely to have amyloid deposits in the brain, too.)

However, what the discovery of amyloid plaque in the brain would mean to a person in practical, real-life terms is, Cummings says, “the nuanced part that is very important to get.”

“If a person has a dementia – they have cognitive impairment and functional impairment – and there is a positive scan, then we’d say that is Alzheimer’s disease or Alzheimer’s dementia,” Cummings says.

“Then there’s a group of people that have mild cognitive impairment, so they’re still playing bridge, still driving, but when you test their memory, it’s not at the level it should be. If they have a positive scan, the likelihood they’re going to go on and get Alzheimer’s dementia – the more severe form of the disease – is very high, like 90 percent over five years.

“Then there is a group of people who have no symptoms, but then you do this scan – maybe for research or because they had a family member (with Alzheimer’s) – and you discover the plaque in the brain,” Cummings says. “This is the group of people we understand least well.

“It would certainly say they are at very high risk to progress to Alzheimer’s disease, but we don’t know that 100 percent do, and we do not know the time frame. Would they start changing within two years or within 15 years, which for an 80-year-old might mean they’re probably never going to have the disease?

“So it’s the interaction between what the scan tells us and the clinical examination. That’s why the doctor is still important here,” Cummings continues. “And that, of course, is why we have to teach the medical community how to use this scan, because you could easily get a positive scan and say, ‘You have Alzheimer’s disease,’ and we don’t think that. We think there’s a lot of uncertainty in what’s going to happen to that person.”

Another thing to consider: Even if amyloid plaque is found in the brain of someone who isn’t showing Alzheimer’s symptoms, there’s nothing that can be done about it.

Right now, there’s no cure for Alzheimer’s disease and no treatments that might prevent it from developing in people who have amyloid plaque but have no symptoms.

That, Cummings says, is why “we discourage people who truly have no symptoms” from being pre-emptively tested, “because, outside of trial settings, we have no treatment.”

Farbman agrees. “At this point, we don’t have any medicine we know of to take in advance to prevent the disease,” he says. “I would not recommend getting a test just to know.”

TEMPTATION TO KNOW

Janke admits that the possibility of finding out one way or another right now is tempting. But so far, she is leaning against being tested.

On the plus side, finding out now would allow a person to prepare, legally and practically, for a possible future of living with Alzheimer’s. (Janke says that, as a single woman, she already has done all of that.)

And, she says, knowing that Alzheimer’s probably will be a part of her future might allow her to seek whatever treatments that do exist earlier. A patient who tests positive might begin to seek out clinical trials of potential Alzheimer’s treatments.

On the minus side, Janke fears that being tested will result in her being labeled as someone who is likely to develop Alzheimer’s.

She fears that conceivably might (despite confidentiality protections provided by law) one day hamper her ability to purchase medical insurance, completely foreclose her from getting long-term care insurance, and even hurt future employment prospects if a potential employer were to find out she’s likely to develop Alzheimer’s.

Besides: If the results do turn out badly, Janke says, “the stress will be there.”

So for now, Janke says no, even if, someday, “I think I will, and at what point I’m not sure.”

Albert Chavez, Southern Nevada regional director for the Alzheimer’s Association’s Desert Southwest Chapter, says Janke’s decision isn’t unusual, given the absence of treatment options available for nonsymptomatic patients.

Many relatives of Alzheimer’s patients “do lean toward, ‘Why should I?’ not wanting to know, especially given the fact that at this point in time there is not a cure,” he says.

Two other hurdles to undergoing the new test: Cummings says it’s expensive – about $4,400 - and it isn’t covered by medical insurance or Medicare.

Keeping a bit of perspective can be useful in weighing the decision. Singh notes that those who have a first-degree relative – a mother, father or natural sibling – with Alzheimer’s “have a three to four times higher chance of developing Alzheimer’s.”

But, he continues, “what happens with Alzheimer’s is, even if you’re at risk, that doesn’t mean you’re definitely going to get it, and if you don’t have a positive family history, that doesn’t mean you’re not going to get it. So, at this point, my recommendation is: Don’t go for testing just because you have a positive family history.”

CANDIDATES FOR TESTING

However, Singh also stresses that people who are showing symptoms should call their doctor and undergo evaluation as soon as possible. That way, treatment and other medical interventions can begin without delay.

Because the difference between normal memory changes that might be related to aging and symptoms of Alzheimer’s can be subtle, only a physician can identify Alzheimer’s disease.

For example, the Alzheimer’s Association’s list of warning signs (www.alz.org) notes that memory loss that disrupts daily life is a warning sign of Alzheimer’s, while occasionally forgetting a name and remembering it later is normal.

Generally speaking, Cummings says, a “loss of recording new information is much more important than the loss of recall of information.”

Farbman agrees. “I would say it’s more than forgetting,” he says. “It can be trouble planning tasks.”

Also, Dr. Douglas Scharre, director of the division of cognitive neurology at Ohio State University, has designed the SAGE test (sagetest.osu.edu), a short, self-administered paper-and-pencil test that helps to screen for potential signs of mild cognitive impairment and early dementia.

“A big problem in Alzheimer’s disease and research is that we’re not catching people early enough,” Scharre says. “There are hundreds of thousands of people out there that have symptoms.

“But no one knows, and their brain is being ravaged by this condition when they could be on some treatment. The symptoms are there, but they’re not going in and telling their doctor about it.”

The test (there are several versions) asks takers to, for example, explain how a bicycle and a train are similar, figure out how many nickels there are in 35 cents, make change from $5, name items that might be found in a kitchen, copy a geometric figure and draw a clock with a specific time on it.

Scharre said the SAGE test can help to set a baseline for determining cognitive changes that might develop over time.

“We recommend giving the test to their doctor after they take it at home,” he says, although “it’s best to be taken at the physician’s office.”

Scharre recommends that the SAGE test be taken by everyone no later than age 65, although “if you have cognitive issues before age 65, then, obviously, look into it.”

He adds that SAGE test results always should be shared with one’s doctor, who may then choose to order additional screenings or even begin therapy.

Singh strongly agrees that anybody exhibiting symptoms – or anyone who is worried that he or she might be – should see a physician for an evaluation so that, if necessary, treatment can begin immediately.

There are five FDA-approved medications for use in treating Alzheimer’s patients, Singh says.

“Then, we can work on certain risk factors which are causing that dementia or making it worse.”

Contact reporter John Przybys at jprzybys@
reviewjournal.com or 702-383-0280.