TORONTO, July 24, 2016 /PRNewswire-USNewswire/
-- Researchers from the Wisconsin Alzheimer's Disease Research
Center and Wisconsin Alzheimer's Institute today presented new data
that suggests that people whose work requires complex thinking
and/or activities are better able to withstand the onset of
Alzheimer's disease. Results — reported at the 2016 Alzheimer's
Association International Conference (AAIC) in Toronto — suggest that working with people,
rather than data or physical things, contributed the most to the
protective effect.
Experience the interactive Multimedia News Release here:
http://www.multivu.com/players/English/7865351-aaic-2016-cognitive-training/
Four additional studies also presented at AAIC 2016 add to the
current body of evidence that modifiable risk factors can help
build resilience to age-related cognitive decline. According to
these reports, formal education, complex work and newly-identified
genes may increase resilience to cognitive decline and dementia,
even in people at high risk for the disease because of unhealthful
diet or blood vessel problems in the brain. Additionally,
resilience factors may vary between men and women at high genetic
risk of Alzheimer's. Finally, a scientifically tailored cognitive
training program led to a reduction in risk of developing cognitive
decline or dementia over the 10-year course of a research
study.
"These new data add to a growing body of research that suggests
more stimulating lifestyles, including more complex work
environments with other people, are associated with better
cognitive outcomes in later life," said Maria C. Carrillo, PhD, Alzheimer's Association
chief science officer.
"As each new study emerges, we further understand just how
powerful cognitive reserve can be in protecting the brain from
disease. As we've heard at AAIC this year, formal education and
complex occupation could potentially do more than just slow
cognitive decline – they may actually help compensate for the
cognitive damage done by bad diet and small vessel disease in the
brain. In metaphorical terms, we can see how cognitive reserve is
taking on super power status," Carrillo said. "It is becoming
increasingly clear that in addition to searching for
pharmacological treatments, we need to address lifestyle factors to
better treat and ultimately prevent Alzheimer's and other
dementias."
Note: "Cognitive reserve"
describes the ability of the brain to withstand damage and maintain
function. Resilience is generally evaluated behaviorally, while
damage is evaluated through microscopic examination of cells and
tissue. Childhood cognition, educational attainment, and adult
occupation all contribute to cognitive reserve.
Cognitive Reserve May Moderate the Adverse Effects of Poor
Diet on Cognition
The role of nutrition as a determinant of
successful aging is a growing area of scientific exploration.
Although the quality of one's diet and indicators of cognitive
reserve have been associated with cognitive function in previous
studies, there is little understanding of how the combination of
these factors may influence cognitive function. In light of that,
this study sought to understand whether indicators of cognitive
reserve protected cognitive function against the impact of poor
diet.
As reported at AAIC 2016, Matthew
Parrott, PhD, of Baycrest Health Sciences, Toronto, Ontario, and colleagues measured
adherence to a traditional "Western" dietary pattern (characterized
by consumption of red and processed meats, white bread, potatoes,
pre-packaged foods and sweets) in 351 independently living older
adults. Alongside each participant's educational attainment,
occupational complexity and social engagement, responses to a
questionnaire on food consumption were analyzed and considered.
Over a three-year period, the researchers found that a "Western"
diet is associated with more cognitive decline in older adults.
However, individuals in the study eating a "Western" diet who also
had a mentally stimulating lifestyle were protected from cognitive
decline.
"Our results show the role higher educational attainment,
mentally stimulating work and social engagement can play in
protecting your brain from cognitive decline, counteracting some
negative effects of an unhealthy diet," said Parrott. "This adds to
the growing body of evidence showing how various lifestyle factors
may combine to increase or protect against vulnerability to
Alzheimer's disease."
Occupational Complexity, Cognitive Reserve, and White Matter
Hyperintensities
It is well-established that white matter
hyperintensities (WMHs) — white spots that appear on brain scans
and indicate cerebrovascular disease — are commonly associated with
Alzheimer's and may confer increased risk for cognitive
decline.
Elizabeth Boots, research
specialist, and colleagues at the Wisconsin Alzheimer's Disease
Research Center and Wisconsin Alzheimer's Institute, evaluated WMHs
in brain scans of 284 late-middle-aged healthy individuals at risk
for Alzheimer's and then compared that data with the participants'
cognitive function and the types of work they do. They explored
three different kinds of complex work situations – work with data,
people and things – to determine which are most effective at
building cognitive reserve in people at risk for Alzheimer's.
The scientists, led by Ozioma
Okonkwo, PhD, found that people with increased white matter
injury who worked primarily with other people, rather than things
or data, were able to tolerate brain damage indicated by WMHs
better than their peers, and better maintain cognitive
function.
"These findings indicate that participants with higher
occupational complexity are able to withstand pathology associated
with Alzheimer's and cerebrovascular disease and perform at a
similar cognitive level as their peers. This association is
primarily driven by work with people, rather than data or things,"
said Boots. "These analyses underscore the importance of social
engagement in the work setting for building resilience to
Alzheimer's disease."
Memory Resilience in Carriers of Alzheimer's Genetic Risk
Varies in Women and Men
At AAIC 2016, Kirstie McDermott and colleagues from the
University of Alberta, Edmonton, reported results from the Victoria
Longitudinal Study, a long-term, large-scale, and multi-faceted
investigation of human aging in western Canada. They looked at how memory resilience
varies in men and women who are genetically susceptible to
Alzheimer's disease.
The researchers investigated whether memory resilience to
established genetic risk factors Apolipoprotein E (APOE) ɛ4
and Clusterin (CLU) C alleles is predicted by modifiable
factors that are sex-specific and genetically robust. They followed
642 non-demented older adult participants aged 53-95 for up to nine
years and assessed their individual episodic memory performance and
trajectory.
Researchers classified participants as resilient if they
sustained higher levels of memory over time despite their
Alzheimer's genetic risk. They examined predictors of resilience
from four Alzheimer's risk domains: (1) demographic (e.g.,
education), (2) functional (e.g., pulse pressure), (3) health
(e.g., mobility), and (4) lifestyle (e.g., cognitive activity). All
analyses were stratified by sex.
They found that, over the course of the study, memory level and
stability was maintained in 67.6 percent of female participants vs.
52.8 percent of male participants. Memory resilience was reliably
predicted by younger age, higher educational level, greater muscle
tone, and participation in challenging, everyday cognitive activity
(such as playing bridge or doing taxes) across sex for both genetic
variants.
However, selectively for women, memory resilience was also
predicted by:
- Force of expiration (a measure of lung function).
- Pulse pressure (a measure of cardiovascular health).
- Mobility factors, such as walking speed.
- Social activities, such as volunteering and visiting family and
friends.
For men, one additional functional factor – less depressive
symptoms – was an important predictor.
"Our results broadly show that while some predictors of memory
resilience to Alzheimer's genetic risk are the same for men and
women, there are also a number of modifiable predictors unique to
gender," McDermott said. "The more we know about both common and
gender-specific factors that may protect against Alzheimer's risk,
the better we can create tailored and appropriate interventions
that promote functional maintenance and delay cognitive
decline."
Linkage and Whole Genome Sequence Analysis of AD Resilience
and Risk
At AAIC 2016, researchers from Brigham Young University, Utah
State University, the University of
Utah and the Washington
University School of Medicine presented an approach that
incorporated linkage analysis, whole genome sequencing (WGS),
validation and biological follow-up to identify candidate
protective gene variants for Alzheimer's. Gene variants that cause
a loss of function, and those that protect from disease, may be
drug targets.
The study examined people over the age 75 who have been able to
remain cognitively normal even in the face of genetic risk for
Alzheimer's disease. Using data from the Cache County Study on
Memory Health and Aging and the Utah Population Database, this
study identified families with several individuals that fit this
definition and looked for shared genetic factors that may explain
their resilience against Alzheimer's symptoms.
Findings detected suggestive linkage in two pedigrees.
Significant association in the protective direction was found for
variants rs142787485 (p=0.018,
OR=0.58) and rs7653 (p=0.0049,
OR=0.35). RAB10 overexpression resulted in a significant increase
in the Aβ42/Aβ40 ratio (p=0.017) and RAB10 silencing resulted in a
significant decrease in the Aβ42/Aβ40 ratio (p=0.048).
Note: Plasma levels of amyloid
β protein (Aβ40 and Aβ42), and the ratio between them, may be
useful for identifying people at increased risk for mild cognitive
impairment and Alzheimer's disease.
"These findings implicate RAB10 as a potential Alzheimer's
resilience gene and suggest that reduced expression of RAB10 may
result in resilience to Alzheimer's via reduced Aβ42 throughout
life," said Keoni Kauwe, PhD, of
Brigham Young University. "RAB10 plays
a role in regulating the production of amyloid beta, and RAB10 is
less active in people resistant to Alzheimer's, therefore we see
RAB10 as a potential therapeutic target for the prevention of
Alzheimer's."
Brain Training May Protect Against Cognitive Impairment and
Dementia: the ACTIVE Study
Cognitive training for the
maintenance of brain health is a growing area of interest,
particularly as it may offer a complement or alternative to drug
therapies in delaying the onset of cognitive decline. At AAIC 2016,
researchers presented 10-year results from the Advanced Cognitive
Training for Independent and Vital Elderly (ACTIVE) study, which
examined the impact of several types of brain training on
cognitively healthy older adults (average age 73.6).
The study examined the effects of cognitive training programs on
2,785 participants at six trial sites in the U.S., who were divided
into three intervention groups – classroom-based memory strategies,
classroom-based reasoning strategies, and computerized
speed-of-processing training – and a control group. The
participants had 10 60-minute training sessions conducted over five
weeks; some participants received "booster" sessions (an additional
four sessions about one year after the original training, and four
more sessions about three years after the original training). The
researchers measured cognitive and functional changes immediately
following the training sessions and at one, two, three, five and 10
years after the training.
After 10 years, only the speed-of-processing training group
showed a statistically significant impact on cognition. The
researchers detected a 33 percent reduction (p=0.012) in new cases
of cognitive impairment or dementia in those assigned to the speed
training group. Participants who did the booster sessions – those
who participated in 11 or more sessions of the computerized
training – showed a 48 percent reduction in news cases of cognitive
decline or dementia. There was no significant difference in the
other two training groups.
Participants in the speed-of-processing group were trained on a
specific task designed to improve the speed and accuracy of visual
attention. The user identifies an object (i.e., a truck) at the
center of his/her gaze while at the same time identifying a target
in the periphery (i.e., a car). As the user gets the answers
correct, the speed of presentation becomes progressively briefer,
while the targets become more similar. In the more difficult
training tasks, the target in the periphery is obscured by
distracting objects.
"We believe this is the first time a cognitive training
intervention has been shown to protect against cognitive impairment
or dementia in a large, randomized, controlled trial," said
University of South Florida associate
professor Jerri Edwards, PhD, first
author of the AAIC 2016 scientific abstract. "Next, we'd like to
get a better grasp on what exactly is the right amount of cognitive
training to get the optimal benefits."
"The Alzheimer's Association believes there is sufficiently
strong evidence to conclude that lifelong learning and certain
types of cognitive training may reduce the risk of cognitive
decline," Carrillo said. "These new 10-year findings are evidence
that it may hold true for dementia as well as cognitive
decline."
Baumgart, et al. Summary of the
evidence on modifiable risk factors for cognitive decline and
dementia: A population-based perspective. Alzheimer's &
Dementia, Volume 11, Issue 6, June 2015, Pages 718–726.
About Alzheimer's Association International Conference
(AAIC)
The Alzheimer's Association International Conference
(AAIC) is the world's largest gathering of researchers from around
the world focused on Alzheimer's and other dementias. As a part of
the Alzheimer's Association's research program, AAIC serves as a
catalyst for generating new knowledge about dementia and fostering
a vital, collegial research community.
AAIC 2016 home page: www.alz.org/aaic/
AAIC 2016 newsroom: www.alz.org/aaic/press.asp
About the Alzheimer's Association
The Alzheimer's
Association is the leading voluntary health organization in
Alzheimer's care, support and research. Our mission is to eliminate
Alzheimer's disease through the advancement of research, to provide
and enhance care and support for all affected, and to reduce the
risk of dementia through the promotion of brain health. Our vision
is a world without Alzheimer's. Visit alz.org or call
800.272.3900.
- Matthew Parrott, PhD, et al.
Indicators of Cognitive Reserve Moderate the Adverse Relationship
Between Poor Diet Quality and Cognitive Decline in Independent
Older Adults: The Nuage Study. (Funders: Canadian Consortium on
Neurodegeneration in Aging; Canadian Institutes of Health Research;
Fonds de recherche de Québec-Santé)
- Elizabeth Boots, BS, and
Ozioma Okonkwo, PhD, et al.
Occupational Complexity, Cognitive Reserve, and White Matter
Hyperintensities: Findings from the Wisconsin Registry for
Alzheimer's Prevention. (Funders: National Institutes of Health;
Alzheimer's Association)
- Kirstie McDermott, BSc, et al.
Memory Resilience in Carriers of Alzheimer's Genetic Risk:
Predictors Vary for Female and Male Older Adults. (Funders:
National Institutes of Health; Canadian Consortium on
Neurodegeneration in Aging (CNNA))
- Keoni Kauwe, PhD, et al. Linkage
and Whole Genome Sequence Analysis of AD Resilience and Risk.
(Funders: National Institutes of Health; Brigham Young University; Donors Cure Foundation -
Charleston Conference on Alzheimer's Disease)
- Jerri Edwards, PhD, et al. The
ACTIVE Study: What We Have Learned and What Is Next? (Funders:
National Institute of Nursing Research; National Institute on
Aging; Indiana Alzheimer Disease Center; Cognitive and Aerobic
Resilience for the Brain Trial)
To view the original version on PR Newswire,
visit:http://www.prnewswire.com/news-releases/formal-education-and-complex-work-may-reduce-the-negative-effects-of-bad-diet-and-cerebrovascular-disease-on-cognition-300303022.html
SOURCE Alzheimer's Association