Looking for Early Signs of Dementia? Ask the Patient
By PAM BELLUCK
Doctors are starting to pay more attention to patients who say they are
experiencing cognitive problems but do not yet show a measurable
decline.
By PAM BELLUCK
Published: July 17, 2013
The man complained of memory problems but seemed perfectly normal. No specialist he visited detected any decline.
“He insisted that things were changing, but he aced all of our tests,”
said Rebecca Amariglio, a neuropsychologist at Brigham and Women’s
Hospital in Boston. But about seven years later, he began showing
symptoms of dementia. Dr. Amariglio now believes he had recognized
cognitive changes so subtle “he was the only one who could identify it.”
Patients like this have long been “called the worried well,” said
Creighton Phelps, acting chief of the dementias of aging branch of the
National Institute on Aging. “People would complain, and we didn’t
really think it was very valid to take that into account.”
But now, scientists are finding that some people with such complaints
may, in fact, be detecting early harbingers of Alzheimer’s. Studies
presented Wednesday at an Alzheimer’s Association conference
in Boston show that people with some types of cognitive concerns were
more likely to have Alzheimer’s pathology in their brains, and to
develop dementia later. Research presented by Dr. Amariglio, for
example, found that people with more concerns about memory and
organizing ability were more likely to have increased levels of amyloid,
a key Alzheimer’s-related protein, in their brains.
And, in a significant shift highlighted at the conference, leading
Alzheimer’s researchers are identifying a new category: “subjective
cognitive decline,” people’s perception of fledgling changes still
invisible to others.
“The whole field now is moving to this area, and saying ‘Hey, maybe
there is something to this, and maybe we should pay attention to these
people,’ ” said Dr. Ronald C. Petersen, chairman of the advisory panel
to the federal government’s new National Alzheimer’s Project.
Dr. Petersen, director of the Mayo Clinic’s Alzheimer’s center, said
preliminary results of a Mayo study of healthy older adults in Minnesota
suggested something similar. “Lo and behold, those who had a concern
about their memory in fact had more likelihood” of later developing mild
cognitive impairment, an early phase of dementia, he said. He said
study participants with memory concerns were 56 percent more likely to
be given a diagnosis of such impairment, even when results were adjusted
for factors like education, genetic risk and psychiatric issues like
anxiety and depression.
“These people are sensing something, and there’s some biological signals
that correlate,” Dr. Petersen said. “I think it’s real.”
Experts emphasize that many people with such complaints will not develop
dementia. Some memory decline reflects normal aging, they say, and some
concerns reflect psychological angst.
And much remains unknown about subjective concerns. In some studies,
like Dr. Amariglio’s, highly -educated people noticed changes more
readily, but in other studies, less-educated people did. Some studies
suggest people who worry more about deficits have more dementia risk,
but it is unclear if the worry reflects the changes they sense or if
worrying itself increases risk. People with family histories of dementia
could be reporting problems simply because they know about the disease
and its genetic component. And, while a study presented Wednesday found
slight correlations between subjective concerns and the highest-risk
genetic mutation, ApoE4, that relationship remains unclear.
Not every memory concern correlated with amyloid buildup, Dr. Amariglio
said. People who forget what they wanted in the kitchen or the names of
relatively unfamiliar people are probably aging normally. People who
forget important details of recent events, get lost in familiar places
or lose track of book or television plots may not be, especially if they
have more problems than others their age.
Experts also are not yet suggesting doctors regularly screen people for
“subjective cognitive decline” because much more research is needed and
no effective dementia treatment now exists.
Dr. Richard Caselli, a neurology professor at the Mayo Clinic in
Arizona, said that when patients cited cognitive problems, he ruled out
“reversible things,” but did not recommend testing for Alzheimer’s
because “if we do a scan and say, ‘Hey, we found some amyloid in your
brain,’ there’s really nothing you can do.”
But subjective screening has value now for clinical trials, experts say,
because it can help pinpoint people at higher risk for dementia to
better determine if treatments can delay or prevent Alzheimer’s.
Major studies like the Alzheimer's Disease Neuroimaging Initiative are
adding subjective memory complaint categories. So will an important
upcoming trial to see if an anti-amyloid drug can prevent dementia in
cognitively normal people with amyloid in their brains.
“People have been interested in this subjective concern for a long time,
but we didn’t have a way to say is this normal,” said Dr. Reisa
Sperling, who runs Brigham and Women’s Alzheimer’s program and is
helping lead the coming anti-amyloid study.
Not long ago, most experts considered subjective concerns unmeasurable
or related to depression or anxiety. Frank Jessen, a researcher at the German Center for Neurodegenerative Diseases,
said his first study on the topic, submitted to journals around 2004,
“got rejected everywhere,” but in 2012, the same study with more years
of data was accepted by Neurology, a major journal.
In November, a working group of leading experts was formed, headed by
Dr. Jessen. The name “subjective cognitive decline” was chosen after
debate over how to characterize people’s perceptions.
Dr. Jessen said in diseases from arthritis to Parkinson’s, people often
feel something is wrong before others notice. In most phases of
dementia, family members and friends see deficits, but the disease has
usually stolen the person’s ability to recognize them. But at the
subjective phase, studies suggest family members may miss problems; the
person may feel his mind working harder, but he still functions well.
One of Dr. Caselli’s patients, Roger Siegel, 84, has noticed problems
for at least five years, and said he now remembers about 30 percent of
what he would like to, and has trouble concentrating. “I take a shower
and wonder did I wash that leg,” he said. In books, “many times I forget
which character is which.”
Recently, he bought six packages of pie filling instead of one “because I
asked somebody where would I find it and the answer was aisle six, so I
wrote down six, but by the time I got to the aisle, I picked up six of
the thing.”
Neither his wife nor Dr. Caselli perceive these difficulties.
“I know I’m losing my mind,” Mr. Siegel said, “but according to Caselli, I’m fine.”
Dr. Caselli said Mr. Siegel has “been saying he is declining for years,”
and was given a diagnosis at another clinic of mild cognitive
impairment three years ago “based on his subjective complaints, when he
had no evidence of decline and I told him so.”
But recently fine-grained cognitive measures showed he had “slight
decline on his tests, and so may possibly be at a very early stage of a
very slowly progressive degenerative syndrome,” Dr. Caselli said.
The working group aims to develop standardized subjective cognitive
tests so when treatments become available doctors can eventually use
them as a “cheap and noninvasive” way to help identify people at greater
risk, said Dr. Petersen. “We can’t do M.R.I.s and scanning on
everyone,” he said.
Current tests range from an eight-page assessment in Dr. Amariglio’s
research to one question included in a University of Kentucky study.
That study was much less detailed, but Richard Kryscio, a
biostatistician and study leader, said those reporting memory changes
since their last visit were nearly three times as likely to develop mild
cognitive impairment or dementia years later, and autopsies of
participants who died found more Alzheimer’s plaques and tangles in
people with subjective cognitive concerns.
Experts say the goal is a test identifying which subjective concerns are potentially worrisome, since not all are.
Sharon Atkinson-Mallory, 70, of Belmont, Mass., a participant in Dr.
Amariglio’s study of people without symptoms, said she had occasional
trouble putting names to faces and remembering why she entered a room.
But Ms. Atkinson-Mallory, a psychotherapist, maintains a part-time
practice, exercises, pursues a genealogy hobby, and considers her issues
similar to those of others her age.
Carol Miller, 61, of Rochester, Minn., part of the Mayo Clinic’s study
of cognitively healthy adults, seems more concerned. A registered nurse
who retired after being laid off a few years ago, she has forgotten
cardiovascular and neurological vocabulary that once “I would recall
very easily,” she said. “I don’t trust myself as a safe R.N. because I
don’t have the knowledge anymore.”
When shopping for blueberry filling for her daughter’s birthday cake,
she twice reached the checkout counter having forgotten it. And twice
she has left the stove on. “I could’ve burned the house down,” she said.
“That was scary, like ‘Wow, what’s the deal there?'”
Still, she said, “so far they tell me I’m normal.” COPY http://www.nytimes.com/
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