News reports of research into Alzheimer's disease July - December 2009
To search by subject, go to Alzheimer's subject index.
Return to Alzheimers main page for monthly index
There's a glossary of terms used in Alzheimer's research.
Disclaimer:
This section began as an offshoot of my
gathering of news items about memory. I am not a medical expert. My
background is in psychology. The information I have gathered here should
not be taken as providing any advice.
December
Apathy common in dementia patients with white matter changes
A study involving 176 patients with Alzheimer's, vascular dementia or mixed
dementia, or mild cognitive impairment, has found that 82% of the patients
with changes in their white matter were apathetic, compared to an overall rate
of 58%. This discovery suggests that there is a common biological reason behind
this apathy, irrespective of which type of dementia a patient has. White matter
changes were also associated with age, gender, blood pressure, hypertension, ischaemic heart disease, mental slowness, disinhibition, gait disturbance and
focal neurologic symptoms. Apathy, mental slowness and age were the most
consistent predicting factors for WMCs.
The findings appeared online ahead of print 22 October in the International
Journal of Geriatric Psychiatry.
Full reference
http://www.eurekalert.org/pub_releases/2009-12/uog-aci120209.php
Tarenflurbil fails clinical trial
In another example of a drug that worked in mice but failed to show a benefit
for patients, a study has found that the drug tarenflurbil, which supposedly
suppresses the accumulation of amyloid plaque—did not slow cognitive decline or
loss of usual daily activities (and was moreover associated with adverse effects
including anemia, pneumonia, and herpes zoster). Although the drug showed
promise in a small clinical trial, the results were negative in this larger,
randomized trial, involving 1684 patients with mild Alzheimer’s. It’s suggested
that rather than focusing on Alzheimer's disease and its specific
characteristics, we should see dementia as a confluence of three common disease
processes—Alzheimer's disease, vascular brain injury, and
Lewy body disease.
The study was published in the December 16 issue of the Journal of the American
Medical Association. Full
reference
http://www.eurekalert.org/pub_releases/2009-12/ghcc-jet121109.php
Higher levels of leptin associated with lower risk of dementia
A new study has showed that higher levels of leptin—a hormone involved in
fat metabolism and appetite—is linked to reduced risk of Alzheimer's disease.
The study used data from the large long-running Framingham Heart Study, and found
that higher leptin levels were not only associated with a dose-related lower
incidence of dementia and Alzheimer’s, but also with higher total cerebral brain
volume. The findings are consistent with recent evidence that leptin improves
memory function through direct effects on the
hippocampus. The strength of the
association was striking (an Alzheimer’s risk of 25% for those with the lowest
levels of leptin compared to 6% for those with the highest levels), and if
confirmed will emphasize the role of lifestyle in preventing and treating
Alzheimer’s.
The study was published in the December 16 issue of the Journal of the American
Medical Association. Full
reference
http://www.eurekalert.org/pub_releases/2009-12/jaaj-hlo121009.php
http://www.eurekalert.org/pub_releases/2009-12/bumc-rfh121009.php
Neurogenesis improved in Alzheimer mice
Studies of adult neurogenesis in
genetically engineered mice have revealed
two main reasons why amyloid-beta peptides and
apolipoprotein E4 impair neurogenesis, and identified drug treatments that can fix it. The findings point
to a deficit in GABAergic neurotransmission or an imbalance between GABAergic
and glutamatergic neurotransmission as an important contributor to impaired
neurogenesis in Alzheimer’s. While stem cell therapy for Alzheimer’s is still a
long way off, these findings are a big step toward that goal.
The findings were described in two papers published in the December issue of
Cell Stem Cell. Full reference
Full reference
http://www.eurekalert.org/pub_releases/2009-12/gi-gsi113009.php
November
Fat around the middle increases the risk of dementia
Data from the Prospective Population Study of Women in Gothenburg, involving
a representative sample of 1,462 nondemented women followed from 1968 at ages
38-60 years, and followed-up in 1974, 1980, 1992, and 2000, has revealed that
women who were broader around the waist than the hips in middle age ran slightly
more than twice the risk of developing dementia when they got old. However,
unlike other studies, no link was found to a high BMI. It should be noted,
though, that obesity and overweight were relatively unusual among the
participants of this study.
The study was published in the November 10 issue of Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-11/uog-fat112309.php
Reduced muscle strength associated with Alzheimer's risk
A study involving 970 older adults (average age 80.3) has found that over the
average 3.6 years follow-up period, those with weaker muscles had a higher risk
of developing Alzheimer’s. For each one-unit increase at the beginning of the
study, older adults had about a 43% decrease in the risk of developing
Alzheimer's disease during follow-up (strength scores ranged from -1.6 to 3.3
units). Those in the top 10% had about a 61% reduced risk of developing
Alzheimer's compared with those in the bottom 10%. The association remained even
after factors such as body mass index and physical activity level were accounted
for. The association also was found with mild cognitive impairment.
The report appeared in the November issue of Archives of Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-11/jaaj-sb110509.php
Better prediction of MCI & Alzheimer’s
New techniques for analyzing imaging data have produced a better means of
telling exactly much brain-volume loss has occurred in each region of the brain,
enabling improved prediction of MCI and Alzheimer’s. The methods require at
least two brain scans to be performed on the same MRI scanner over a period of
several months.
The study was published in the December 8 issue of the Proceedings of the
National Academy of Sciences (PNAS).
Full reference
http://www.eurekalert.org/pub_releases/2009-11/uoc--asb111609.php
Impact of Alzheimer's gene on healthy brains
And another new imaging analysis technique has cast light on the impact of
the Alzheimer’s gene ApoE4 in healthy brains. Healthy older adults with the gene
were found to have reduced cognitive performance, decreased brain volume in the
hippocampus and
amygdala, and decreased
white matter integrity in the left
parahippocampal gyrus.
The results were published in the November issue of the Journal of Alzheimer's
Disease. Full reference
http://www.eurekalert.org/pub_releases/2009-11/ip-nna111709.php
Amyloid beta protein not all bad
Two studies have just come out with the news that
amyloid beta, the scourge
of Alzheimer’s, has a vital role to play in memory.
A mouse study has found that young, healthy mice that received low doses of
amyloid beta protein showed improvement in recognizing objects and successfully
navigating through a maze. Conversely, mice that received a drug that blocked
amyloid beta protein had learning impairment. The finding suggests that efforts
to reduce amyloid beta need to take care not to reduce it too much. Clearly
there is a ‘right’ amount.
The report will be published in a forthcoming issue of the Journal of
Alzheimer's Disease. Full
reference
http://www.eurekalert.org/pub_releases/2009-11/slu-abp110909.php
http://www.j-alz.com/press/2009/20091110.html
Cell culture studies also reveal that there is an optimal amount of amyloid beta
needed to keep the neurons working well. If this precise balance is even
slightly disturbed, the effectiveness of information transfer between neurons is
greatly impaired.
The study was published in the December issue of Nature Neuroscience.
Full reference
http://www.eurekalert.org/pub_releases/2009-11/afot-uts112309.php
Mixed pathology of dementia indicates combination therapies needed
Data from the Medical Research Council's Cognitive Function and Ageing Study,
including post-mortem study of the brains of 456 participants, has enabled
researchers to estimate the contribution of each type of pathology to dementia
in the population as a whole. The main pathological contributors to dementia
were age (18%), small brain (12%), amyloid plaques (8%) and
neurofibrillary tangles (11%),
small blood vessel disease (12%), multiple vascular pathologies (9%), and
hippocampal atrophy (10%). Other significant factors include cerebral amyloid
angiopathy (7%) and Lewy bodies (3%). The findings support the need for a
range of strategies, and combination therapies, tailored to the particular needs
of the patient. It also points to why particular therapies may be more
successful with some individuals but not others.
The study was published in the open access journal PLoS Medicine.
Full reference
Full text available at
http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1000180
http://www.eurekalert.org/pub_releases/2009-11/plos-utp110409.php
More on the genetic component of frontotemporal dementia
A study involving 225 people diagnosed with frontotemporal dementia has found
that nearly 42% of participants had some family history of dementia. However,
many people had a strong family history of dementia without having any of the
five known gene mutations, suggesting that there are still unknown genes that
cause frontotemporal dementia. The behavioral variant was most likely to be
hereditary, while FTD-motor neuron disease and the language syndromes
(particularly semantic dementia) were the least likely to be hereditary.
The study was published in the November 3 issue of Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-11/aaon-idt102709.php
October
Recommended: Use of antipsychotic drugs for dementia patients should be curtailed
A report just out from the U.K. Department of Health has concluded that as
many as 144,000 dementia patients are being given anti-psychotic drugs
unnecessarily, and that excessive use of the medication causes an estimated
1,800 deaths and almost as many strokes every year. It recommended that the use
of the drugs could be cut by two-thirds over the course of the next three years,
but urged carers and family not to act hastily, warning that stopping
prescriptions immediately for many patients could be dangerous.
http://www.guardian.co.uk/society/2009/nov/12/anti-psychotic-drugs-kill-dementia-patients
http://news.bbc.co.uk/2/hi/health/8356423.stm
High protein diet shrinks brain in Alzheimer’s mice
A study using genetically engineered mice has tested the effects of four
diets for their effects on Alzheimer’s pathology: a regular diet, a high fat/low
carbohydrate custom diet, a high protein/low carb version, or a high
carbohydrate/low fat option. Unexpectedly, mice fed the high protein/low
carbohydrate diet had brains 5% lighter that all the others, and regions of
their hippocampus were less developed. Mice on the high fat diet had higher
levels of amyloid-beta protein, although no effect on
plaque burden was
detected.
The study was published 21 October in the open access journal Molecular
Neurodegeneration. Full
reference
Full text available at
http://www.molecularneurodegeneration.com/content/4/1/40
http://www.eurekalert.org/pub_releases/2009-10/bc-arf101909.php
Does diabetes speed up memory loss in Alzheimer's disease?
A four-year study involving 608 people with mild to moderate Alzheimer's
disease, of whom just over 10% (63) had diabetes, has unexpectedly found that
memory loss in those without diabetes declined faster than those with diabetes.
The researchers speculate that elderly people with diabetes may be more likely
to be taking cardiovascular medications (although having vascular factors was
controlled for), or there may be some differences in the brain pathology of
Alzheimer’s with diabetes compared to Alzheimer’s without diabetes.
The research was published in the October 27 issue of Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-10/aaon-dds102009.php
Declines in other thinking and learning skills may precede memory loss in Alzheimer's disease
A long-running study investigating early signs of dementia involved 444
individuals who were dementia-free at enrolment, of whom, over an average
follow-up of 5.9 years, 134 developed dementia. The study found that
visuospatial abilities showed a sudden drop three years before clinical
diagnosis. Declines in overall cognitive abilities followed in the next year.
Verbal and working memory — the most obvious symptoms — were not seen until one
year before diagnosis. The findings point to the need to test a broader range of
cognitive skills than the standard episodic and verbal tests.
The report appeared in the October issue of Archives of Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-10/jaaj-dio100809.php
Risk of abnormally slow heart rate twice as high in those taking Alzheimer's drugs
Data from 1.4 million Canadians aged 67 and older has revealed that older
patients hospitalized with bradycardia were more than twice as likely to have
recently started on a
cholinesterase inhibitor such as
donepezil for Alzheimer's disease
compared to those without bradycardia. Bradycardia is an abnormally slow resting
heart rate (under 60 beats per minute). Although it can be asymptomatic, it can
also cause fainting, palpitations, shortness of breath, or even death. Although
there are three cholinesterase-inhibiting drugs approved for use in Canada, most
had been prescribed donepezil. The findings add weight to recent guidelines
suggesting that doctors should not prescribe cholinesterase inhibitors for
dementia patients as a matter of course, but weigh the potential risks and
benefits.
The findings appear in the September 2009 issue of PLoS Medicine.
Full reference
Full text available at
http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1000157
http://www.eurekalert.org/pub_releases/2009-10/smh-roa100109.php
Benefit of memantine in the treatment of Alzheimer's disease not proven
A review of the use of memantine for patients with moderate or severe
Alzheimer's disease has concluded there is no scientific evidence of any benefit
to this group, either to patients or caregivers. The review covered 7 studies,
involving 1913 patients. The longest study lasted 28 weeks. The main problem was
a lack of reliable evidence, and a lack of studies of longer duration, as well
as a lack of research with relevant patient groups.
http://www.eurekalert.org/pub_releases/2009-10/ifqa-bom102809.php
Guide to diagnosing the visual variant of Alzheimer's
In a small number of Alzheimer's patients the disease shows up first as
problems with vision rather than memory or other cognitive functions; these
patients are generally younger than usual. Neuro-ophthalmologists who examined
and followed 10 patients with unexplained vision loss who were ultimately
diagnosed with the visual variant of Alzheimer's disease (VVAD) describe
clinical clues that may improve ophthalmologists' ability to detect VVAD. The
median age was 65. Although most patients' visual acuity was adequate, all but
one had difficulty with reading, 8 of 10 with writing, and 6 of 10 with basic
calculations. The visual field was altered in 8 of 10 patients. All had trouble
identifying colored numbers despite being able to name colors correctly, and,
importantly, 8 of 10 patients had difficulty recognizing and interpreting
components of a complex image (simultagnosia).
The report was presented at the 2009 Joint Meeting of the American Academy of
Ophthalmology (AAO) and the Pan-American Association of Ophthalmology (PAAO),
October 24-27, San Francisco, CA.
http://www.eurekalert.org/pub_releases/2009-10/aaoo-ctv101909.php
Protein identified that counterbalances Alzheimer's proteins
A mouse study has revealed that a protein called Reelin may provide a new
approach to tackling Alzheimer’s. Reelin activates and strengthens the response
of the NMDA receptor, which plays an important role in coordinating chemical
signals between adjacent nerve cells. In the presence of too much
amyloid-beta
protein (as occurs in an Alzheimer’s brain), the receptor migrates into the
cell, reducing the cell's sensitivity to incoming signals. However, with strong
concentrations of Reelin, the receptor remains active and the cell continues
receiving normally. The findings also make a connection with
ApoE4 — the
receptor that binds to ApoE also binds to Reelin, and is part of the complex
that controls the sensitivity of the NMDA receptors.
The findings were reported in the September 15 issue of Proceedings of the
National Academy of Sciences.
Full reference
http://www.eurekalert.org/pub_releases/2009-10/usmc-nfa100609.php
September
Difficulties with daily activities associated with progression to dementia
A study involving 111 older adults with mild cognitive impairment, of whom 28
progressed from mild cognitive impairment to dementia over the next 2 ˝ years,
found only one factor predicted conversion from mild cognitive impairment to
dementia: the degree of functional impairment (ability to perform routine
activities) at the beginning of the study. Other cognitive and neurological
variables were not predictive.
The report appeared in the September issue of Archives of Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-09/jaaj-dwd091009.php
Problems managing money may be early sign of Alzheimer's
A study involving 76 older people with no memory problems and 87 older people
with amnestic mild cognitive impairment has found that those (25 of the 87) who
had developed Alzheimer’s a year later were significantly worse at a money
management task. Compared to those with no memory problems, as well as those
with MCI who did not develop dementia, those who did develop Alzheimer’s not
only dropped 9% on checkbook management abilities and 6% on overall financial
knowledge and skills, but also performed more poorly at the beginning of the
study. The task included counting coins, making grocery purchases, understanding
and using a checkbook, understanding and using a bank statement, preparing bills
for mailing, and detecting fraud situations.
The study was published in the September 22 issue of Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-09/aaon-pmm091509.php
http://www.eurekalert.org/pub_releases/2009-09/uoaa-pmm091609.php
Phone assessment effective for evaluating cognition in the elderly
A study of 54 healthy women with an average age of 79, in which the women
received either telephone assessment of cognitive ability followed by in-person
assessment, or vice versa, has found that telephone assessment produced similar
results on most neuropsychological tests (the exceptions were digit span
backward, Oral Trail Making Test Part A, and delayed recall on the SRT). While
not advocating that telephone assessment should replace in-person assessment,
the results indicate that telephone assessment is a cost-effective and time
efficient alternative, that may be particularly useful in circumstances where it
is difficult for the person to attend a clinic. However, the differences on some
measures point to the need for care in selecting the tests.
The study appeared online August 20 in the International Journal of Geriatric
Psychiatry. Full
reference
http://www.eurekalert.org/pub_releases/2009-09/tmsh-msr091509.php
Infections may lead to faster memory loss in Alzheimer's disease
A 6-month study involving 222 people with Alzheimer's disease (average age
83) has found that people who had infections or even bumps and bruises from a fall were more likely to have high
blood levels of tumor necrosis factor-α, a protein involved in the inflammatory
process, and were also more likely to experience memory loss or cognitive decline than people who did not have infections and who had low levels
of the protein. Nearly half the participants experienced an infection or
injury that led to inflammation during the study, and they experienced memory
loss that was at twice the rate of those who did not have infections or
injuries. Those with high levels of the protein in their blood at the beginning
of the study had memory loss at four times the rate of those with low levels of
the protein at the start of the study, and those with high levels who also
experienced acute infections during the study had memory loss at 10 times the
rate of those who started with low levels and had no infections over the
six-month period.
The research was published in the September 8 issue of Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-09/aaon-iml090109.php
Olive oil compound may help against Alzheimer's
Oleocanthal, a naturally-occurring compound found in extra-virgin olive oil,
has been found to change the size of ADDLs, impeding their ability to bind to
synapses — thought to be a crucial first step in Alzheimer’s development. The
compound also protected synapses from structural damage caused by ADDLs.
The findings were reported in the October 15 issue of Toxicology and Applied
Pharmacology. Full
reference
http://www.eurekalert.org/pub_releases/2009-09/mcsc-omh092909.php
Alzheimer's-fighting compounds need regular consumption
A rat study has found that the amount of
polyphenols from grapeseed extract
that can reach the brain is as much as 200% higher on the 10th consecutive day
of feeding as compared to the first. The finding points to the value of regular
consumption. Polyphenols are thought to prevent the formation of beta-amyloid
protein.
The paper was published in the September issue of the Journal of Alzheimer's
Disease. Full reference
http://www.eurekalert.org/pub_releases/2009-08/pu-ssh081709.php
Three new genes associated with Alzheimer's found
Only one gene, ApoE4, has been
associated with the non-familial (common) form of Alzheimer’s. Now the largest
ever Alzheimer's genome-wide association study
involving 16,000 individuals, has found three more. CLU or ApoJ (which produces
a protective protein called clusterin or apolipoprotein J), PICALM (important at
synapses and involved in transporting molecules within and into nerve cells),
and CR1. Both CLU and CR1 have previously been implicated in the clearance of
amyloid beta peptide. CLU is encoded on chromosome 8, CR1 on chromosome 1, and
PICALM on chromosome 11.
Two papers were published online September 6 in Nature Genetics.
Full reference
Full reference
http://www.eurekalert.org/pub_releases/2009-09/art-lea090309.php
http://www.guardian.co.uk/science/2009/sep/06/alzheimers-disease-genes-research
Poor sleep linked to later development of Alzheimer's
A mouse study has found that amyloid-beta significantly increases during periods
of sleep deprivation. The discovery follows observation that peptide levels in
both mice and humans increase significantly during the day and drop at night.
When mice were only allowed to sleep four hours a day for 21 days, they had
higher amyloid-beta plaque build-up in their brain than similar-aged mice with
regular sleeping habits. The circadian fluctuation was found to reflect the
activity of orexin, a hormone that regulates wakefulness. The
findings suggest insomnia, late-night habits, and irregular sleep schedules
during mid-life may be linked to the later development of Alzheimer's disease.
The study was published online September 24 in ScienceExpress.
Full reference
http://www.the-scientist.com/blog/display/55996/
Alzheimers linked to lack of Zzzzs
Greater dementia risk in former N.F.L. players
A study commissioned by the National Football League reports that Alzheimer’s
disease or similar memory-related diseases appear to have been diagnosed in the
league’s former players vastly more often than in the national population:
five times the national average among those 50 and older (6.1%)and 19 times for
those aged 30 through 49. The
findings are consistent with several recent studies regarding N.F.L. players and
the effects of their occupational head injuries. The study involved a phone
survey of 1,063 retired players (from an original random list of 1,625), who were asked questions derived from the standard
National Health Interview Survey. Some health issues were reported at higher
than the population rate (sleep apnea
and elevated cholesterol — both risk factors for cognitive problems).
http://www.nytimes.com/2009/09/30/sports/football/30dementia.html
August
Exercise and Mediterranean-type diet associated with lower risk for Alzheimer's
A New York study involving 1880 elderly (average age 77) is the first to
investigate both exercise and diet in connection with the later development of
Alzheimer’s (within a five and a half year period). Participants were asked
about their activity in the two weeks prior to the interview, about the
regularity and duration, as well as the quality (vigorous, moderate, light).
They were also asked about their food consumption over the previous year, and
their responses grouped into nine food categories, the sum of which represented
a Mediterranean-type diet score. Those who were very physically active had a 33%
risk reduction of Alzheimer's; those who adhered more strongly to a
Mediterranean-type diet had a 40% risk reduction. Those who did both had a 60%
reduction. A Mediterranean-type diet is typically characterized by high intake
of fish, vegetables, legumes, fruits, cereals and monounsaturated fatty acids;
relatively low intake of dairy products, meats and saturated fats; and moderate
alcohol consumption.
The report appeared in the August 12 issue of the Journal of the American
Medical Association.
Full reference
Full text available at
http://jama.ama-assn.org/cgi/content/full/302/6/627?home
http://www.eurekalert.org/pub_releases/2009-08/cumc-eam080609.php
Cognitive activities may delay memory decline in dementia
A 5-year study involving 488 people age 75 to 85 found that, for the 101
people who developed dementia, the more stimulating activities they engaged in,
the longer rapid memory loss was delayed. Participants reported at the beginning
of the study how often they participated in six activities: reading, writing,
doing crossword puzzles, playing board or card games, having group discussions,
and playing music. For each activity, daily participation was rated at seven
points, several days a week was rated at four points, and weekly participation
was rated at one point. The average was seven points total for those who later
developed dementia, meaning they took part in one of the six activities each
day, on average. Ten people reported no activities, and 11 reported only one
activity per week. Accelerated decline was delayed by more than two months for
each activity, so for example a person participating in 11 activities per week
put off rapid decline by 1.29 years compared to a person participating in only
four activities per week.
The study was published in the August 4 issue of Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-08/aaon-em072809.php
Different effects of ministrokes & strokes
A study involving 679 seniors (65+) has found that those with small areas of
brain damage called white matter hyperintensities, often referred to as
ministrokes, were nearly twice as likely to have mild cognitive impairment that
included memory loss (amnestic MCI), while those who had infarcts (areas of dead
tissue usually called strokes) were more likely to experience mild cognitive
impairment in abilities other than memory loss (non-amnestic MCI). In other
words, ministrokes predicted memory problems, while strokes predicted non-memory
problems.
The research was published in the August 11 issue of Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-08/aaon-bds080409.php
Oxygen treatment hastens memory loss in Alzheimer's mice
A study using genetically engineered mice has found that young adult
Alzheimer's mice exposed to 100% oxygen during several 3-hour sessions
demonstrated substantial memory loss, while those exposed to normal air had no
measurable memory loss, and neither did normal mice without any genetic
predisposition for Alzheimer's disease. The results suggest that people
genetically predisposed to Alzheimer's disease or with excessive amounts of
beta amyloid in their brains are at increased risk of developing the disease earlier
if they receive high concentrations of oxygen, for example during or after
surgery. The findings may help explain why some elderly patients develop memory
loss after major surgery.
The study is published in the August 5 issue of NeuroReport.
Full reference
http://www.eurekalert.org/pub_releases/2009-08/uosf-oth081109.php
July
Close caregiver relationship may slow Alzheimer's decline
A study of 167 pairs of caregivers and Alzheimer's patients has found that by
the end of the study patients whose caregivers had scored their relationship as
particularly close lost less than half as many points on average on a common
cognitive test called the Mini-Mental State Exam (MMSE) as patients with more
distant caregivers. The scores were based on a survey in which caregivers rated
their level of agreement or disagreement with six statements, such as "My
relationship with the care recipient is close"; "The care recipient makes me
feel like a special person"; and "The care recipient and I can always discuss
things together." The effect was strongest when the caregiver was a spouse, as
opposed to an adult child or in-law. Patients with close spouses showed rates of
decline similar to patients taking
Alzheimer's drugs called acetylcholinesterase inhibitors. However, it can’t be
ruled out that the effect may be due to slower decline encouraging caregivers to
remain close. A follow-up study is planned to answer this question.
The report was published online June 29 and will appear in the September issue
of The Journals of Gerontology Series B: Psychological Sciences and Social
Sciences. Full reference
http://www.eurekalert.org/pub_releases/2009-07/jhmi-ccr072209.php
Caffeine reverses memory impairment in Alzheimer's mice
Consistent with earlier indications that moderate caffeine consumption may
protect against memory decline, a study of genetically engineered mice has found
that when the old mice began to show memory impairment, those given caffeine for
2 months performed as well as normal aged mice on cognitive tests, while those
given plain drinking water continued to do poorly. The Alzheimer's mice received
the equivalent of five 8-oz. cups of regular coffee a day (or two cups of
Starbucks coffee, or 14 cups of tea). Moreover, the brains of the caffeinated
mice showed nearly a 50% reduction in levels of
beta amyloid. The effect appears
to be through suppression of both β-secretase and
presenilin 1 /g-secretase
expression. Caffeine had this effect only on those with Alzheimer’s; normal mice
given caffeine through adulthood showed no cognitive benefit.
The research was published in two papers in the July issue of the Journal of
Alzheimer's Disease.
Full reference
Full reference
http://www.eurekalert.org/pub_releases/2009-07/uosf-crm070109.php
White matter changes may predict dementia risk
In a study in which 49 seniors (65+) were followed for an average of 9.5
years, of whom 24 developed mild cognitive impairment, those with the fastest
rate of growth in white matter lesions were more likely to develop mild
cognitive impairment than those with a slow rate of growth. The amount of
lesions in healthy brains at the start of the study was not a factor; the
crucial factor was the rate of progression.
The study was published in the July 14 issue of Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-07/aaon-wmc070709.php
Language skills in your 20s may predict risk of dementia decades later
Confirming earlier indications, autopsies of the brains of 38 Catholic nuns
in the Nun Study has found that those who had no memory problems, whether or not
their brains showed Alzheimer’s disease hallmarks, had higher early language
scores compared to those who showed symptoms of Alzheimer’s or
mild cognitive
impairment. Early language was assessed in terms of the number of ideas produced
every 10 words in the essays they wrote in their late teens or early 20s when
they entered the Order. There was no effect in terms of grammatical complexity.
Those with Alzheimer's disease hallmarks and no memory problems also had
enlarged neurons in the CA1 region of the
hippocampus.
The research was published online July 8 in Neurology.
Full reference
http://www.eurekalert.org/pub_releases/2009-07/aaon-lsi070109.php
Some blood pressure drugs may help protect against dementia
High blood pressure is a major contributor to the development of all types of
dementia. Data from over 1000 participants in the Cardiovascular Health Study,
who were free of dementia when they entered the study and who were being treated
for hypertension, has revealed that those taking centrally-active ACE inhibitors
(which cross the blood-brain barrier) showed significantly lower rates of mental
decline. However, non-centrally active ACE inhibitors were associated with an
increased risk of dementia compared to those taking other anti-hypertensive
drugs. Centrally-acting ACE inhibitors include captropril (Capoten®), fosinopril
(Monopril®), lisinopril (Prinivil® or Zestri®), perindopril (Aceon®), ramipril (Altace®)
and trandolapril (Mavik®).
The study appears in the July 13 issue of Archives of Internal Medicine.
Full reference
http://www.eurekalert.org/pub_releases/2009-07/wfub-sbp072009.php
Neural stem cells offer potential treatment for Alzheimer's
Genetically engineered mice performed markedly better on memory tests a month
after neural stem cells were injected into their Alzheimer-like brains. The stem
cells secreted a protein that created more neural connections, improving
cognitive function. Surprisingly, only 6% of the stem cells became neurons (most
became ‘support cells’:
astrocytes and
oligodendrocytes). The benefit of stem
cells seemed rather to lie in their secretion of
BDNF, which encouraged the
formation of new synapses. The direct injection of BDNF also had cognitive
benefit, but not as much as with the neural stem cells, which provided a more
long-term and consistent supply of the protein.
The study appeared in the August 11 issue of Proceedings of the National Academy
of Sciences. Full
reference
Full text available at
http://www.pnas.org/content/106/32/13594.abstract
http://www.eurekalert.org/pub_releases/2009-07/uoc--nsc072009.php
Conference proceedings
From the Alzheimer's Association International Conference on Alzheimer's Disease
July 11-16 in Vienna.
more reports in main July
news
Mixed results from trials of DHA
A large 18-month trial of the effects of DHA, an omega 3 fatty acid, on 402
people with mild to moderate Alzheimer's found no evidence of benefit. However,
there were indications that those without the “Alzheimer’s gene” ApoE-e4 showed
slower cognitive decline. A 6-month trial involving 485 healthy seniors with
mild memory complaint also found a benefit on a test of memory and learning.
Full reference
Full reference
http://www.eurekalert.org/pub_releases/2009-07/aa-rft070709.php
Poor Understanding of Alzheimer's Link to Heart Health Risk Factors
An online survey of 690 adults (average age 50; well-educated, with 87% having had some college) found that 64% did not realize there was an association between Alzheimer's and obesity or high blood pressure; 66% didn’t know that high stress is a risk factor for dementia; 34% didn’t know that physical exercise is a protective factor. Full reference
PTSD Linked to Nearly Double Dementia Risk in Veterans
Data from 181,093 veterans aged 55 years and older without dementia (53,155 veterans diagnosed with PTSD and 127,938 veterans without PTSD) found that PTSD patients were nearly twice as likely to develop incident dementia compared to veterans without PTSD. Results were similar when we excluded those with a history of traumatic brain injury, substance abuse or depression. Full reference
