The
study, by scientists at the Rush Alzheimer's Disease Center and Rush-Presbyterian-St.
Luke's Medical Center in Chicago, IL, appearing in the February 13,
2002, Journal of the American
Medical Association, found that more frequent participation in
cognitively stimulating activities is associated with a reduced risk
of Alzheimer's disease (AD). The research looked at everyday activities
like reading books, newspapers or magazines, engaging in crosswords
or card games, and going to museums among participants in the Religious
Orders Study, an ongoing examination of aging among older Catholic
nuns, priests, and brothers from several groups across the U.S. On
a scale measuring cognitive activity -- with higher scores indicating
more frequent activity -- a one-point increase in cognitive activity
corresponded with a 33 percent reduction in the risk of AD.
The
examination of cognitively stimulating activities and risk of AD was
conducted by Robert S. Wilson, Ph.D., and colleagues at the Rush Alzheimer's
Disease Center, including David A. Bennett, M.D., principal investigator
for the Religious Orders Study, and Denis A. Evans, M.D., director
of the National Institute on Aging (NIA)-supported Rush Alzheimer's
Disease Center.The NIA is part of the National Institutes of Health, Department
of Health and Human Services.
The
findings are likely to strike a chord among middle-aged and older
people interested in preserving cognitive health. "We are asked constantly
about this use-it-or-lose-it approach to maintaining memory," says
Elisabeth Koss, Ph.D., Assistant Director of the NIA's Alzheimer's
Disease Centers Program. "This study provides important new evidence
that there may be something to the notion of increased cognitive activity
and reduced risk of Alzheimer's disease. Further research should help
better sort out whether cognitive activities can be prescribed to
reduce risk of AD and why that may be so."
The
study followed over 700 dementia-free participants age 65 and older
for an average of 4.5 years from their initial assessments.At baseline and then yearly, some 21 cognitive tests were administered
to assess various aspects of memory, language, attention, and spatial
ability. At the initial evaluations, participants also were asked
about time typically spent in seven common activities that significantly
involve information processing - viewing television; listening to
the radio; reading newspapers or magazines; reading books; playing
games such as cards, checkers, crosswords, or other puzzles; and
going to museums.The
frequency of participating in each activity was rated on a five-point
scale, with the highest point assigned to participating in an activity
every day or about every day and the lowest point to engaging in an
activity once a year or less.
During
the follow-up period, 111 people in the study developed AD.In comparing the levels of cognitive activity with diagnosis
of AD, the researchers found that the frequency of activity was related
to the risk of developing AD.For each one point increase in the participants' scores on
the scale of cognitive activities, the risk of developing AD decreased
by 33 percent.On average,
compared with someone with the lowest activity level, the risk of
disease was reduced by 47 percent among those whose frequency of activity
was highest.
The
researchers also looked at general cognitive decline among the participants.Over the period of the study, the group of older people showed
modest age-related declines on several types of memory and information
processing tests.There were lower rates of decline, however, in working memory,
perceptual speed, and episodic memory among people who did more cognitively
stimulating activities.
What
accounts for the association between cognitively stimulating activities
and reduced risk of cognitive decline and AD is unclear. It may be,
some scientists theorize, that cognitive activities are protective
in some way.Some speculate
that repetition might improve the efficiency of certain cognitive
skills and make them less vulnerable to the brain damage in AD.Or, some kind of compensatory mechanisms might be at work,
strengthening information processing skills to help compensate for
age-related declines in other cognitive areas. The study does not,
however, eliminate the possibility that people who develop AD in future
years may be less prone, years before, to engage in cognitively stimulating
activities. Notes Wilson, "The associations among cognitive activity,
Alzheimer's disease, and cognitive function are extremely complex.Additional study, including testing some of these activities
as cognitive interventions, will help to tell us whether such enjoyable
and easy-to-do activities could be employed in some way to reduce
the risk of memory decline and loss."Because the participants in the study have agreed to brain
donation, the investigators hope to be able to determine the mechanism
underlying the association between cognitive activities and cognitive
decline.
More
than 900 older Catholic clergy from 40 groups across the U.S. are
participating in the Religious Orders Study. All participants have
agreed to annual memory testing and brain donation at the time of
death. "We are grateful for the remarkable dedication and altruism
of this unique group of people," says Bennett. "I expect we will learn
a great deal more from them, as we look for insights into how the
brain functions with age.
The
NIA leads the Federal effort to support and conduct research on aging
and on AD.The Rush Alzheimer's Disease Center is one of 29 NIA-supported
Alzheimer's Disease Centers across the U.S. which conduct basic, clinical,
and social and behavioral research on dementia and AD. NIA also sponsors
the Alzheimer's Disease Education and Referral (ADEAR) Center, which
provides information on AD research to the public, health professionals,
and the media.ADEAR
can be contacted toll free at 1-800-438-4380 weekdays during business
hours or by visiting its website, www.alzheimers.org.Press releases, fact sheets, and other general information
materials on aging and aging research can be viewed at the NIA's home
website, www.nia.nih.gov.
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