Older
adults who notice new problems with balancing the checkbook or reading the
newspaper may be at increased risk of dementia in the coming years, according
to four new studies.
The
research, being presented this week at the Alzheimer's Association
International Conference in Boston, suggests that older adults' concerns about
their memory could serve as an early warning sign of future dementia.
That may
not sound surprising. But it has not been clear whether people's subjective
perceptions of memory slips are a reliable predictor of more-severe problems
down the road.
Older
adults who complain of memory issues, but test "normal" on standard
cognitive (thinking) tests, have often been dismissed as the "worried
well," said Rebecca Amariglio, a neuropsychologist with Brigham and
Women's Hospital in Boston who led one of the new studies.
Her team
found evidence that older adults' concerns may be more significant.
The study
included 131 adults who were 73 years old, on average, and had normal scores on
formal tests of memory and thinking. To get at the participants' subjective
perceptions, the researchers gave them a separate, detailed questionnaire that
asked them to rate any problems they had with everyday tasks, like remembering
things they've just read or been told. It also asked them how well they thought
their mental skills measured up compared with a decade ago.
Next, the
researchers used PET scans to image participants' brains.
It turned
out that people with bigger subjective concerns about their mental sharpness
had a higher level of beta-amyloid proteins in the brain. Beta-amyloid buildup
is considered a risk factor for Alzheimer's.
It's not
known yet whether the study participants who were worried about their memories
actually face a greater Alzheimer's risk, Amariglio said.
She also
stressed that older adults need not be alarmed by the "senior
moments" that crop up as you age -- like walking into a room and
forgetting why you went there, or having trouble remembering an unfamiliar
person's name.
An expert
not involved in the study agreed.
"We're
not talking about those times you walk out of your house and realize you've
forgotten your keys," said Heather Snyder, director of medical and scientific
operations for the Alzheimer's Association.
"We're
talking about cases where you identify a change over time -- you've always been
able to balance your checkbook with no problem, but now you're having
difficulty," she explained.
Even those
issues do not necessarily mean you are on a course to develop Alzheimer's or
other forms of dementia. But if you notice such changes, it is something to
bring up to your doctor, Snyder said.
Three other
studies presented at the meeting uncovered evidence that subjective memory
concerns may serve as red flags:
In a study
of nearly 3,900 U.S. women aged 70 and up, those with memory concerns were more
likely to show declining scores on objective memory tests over the next six
years. The link was most clear among women who carried the ApoE4 gene variant
-- the strongest known genetic risk factor for Alzheimer's.
Another
study followed 531 older adults who took annual cognitive tests for a decade.
Before each test, they were asked if they'd noticed changes in their mental
abilities in the past year. Those who said they had were twice as likely to be
diagnosed with mild cognitive impairment or dementia at some point during the
study. On average, participants noticed changes six to nine years before their
diagnosis.
German
researchers found that of 2,230 elderly adults who were free of obvious
impairment, those who thought their memories were getting worse showed a
steeper decline in objective memory tests over the next eight years.
The
findings all raise the possibility that evaluating memory complaints could help
doctors spot older adults at increased risk of dementia. But Snyder said it's
too soon to say for sure.
"We
don't know yet how this all could be used as a potential tool," Snyder
said.
Amariglio
agreed. She said the questionnaire from her study is not ready for doctors to
use in everyday practice. Instead, it might help researchers find candidates
for ongoing clinical trials that are studying drugs or lifestyle measures to
hopefully slow down Alzheimer's progression.
Right
now, there is no known way to prevent or delay Alzheimer's. But if researchers
do find such a therapy, Amariglio said, a questionnaire that helps spot older
adults at risk would become very important.
For
now, Snyder recommended that older adults who notice changes in their mental
acuity tell their doctors. "If there's a concern, you can be further
evaluated," she said.
Alzheimer's
disease is the most common form of dementia, and experts estimate that if no
progress is made in delaying or preventing the disease, the number of Americans
with Alzheimer's could triple by 2050, to nearly 14 million.
Along
with the emotional toll for families, there is the cost of caring for people
with Alzheimer's. A recent study estimated that in 2010, the United States
spent up to $215 billion on care for people with Alzheimer's and other forms of
dementia.
Because
the new studies were presented at a medical meeting, the data and conclusions
should be viewed as preliminary until published in a peer-reviewed journal.

No comments:
Post a Comment