Wednesday, November 14, 2012
Avoiding Dementia Part II
Eating Fish, Chicken, Nuts May Lower Risk of Alzheimer's Disease
A new study suggests that eating foods that contain omega-3 fatty acids, such as fish, chicken, salad dressing and nuts, may be associated with lower blood levels of a protein related to Alzheimer's disease and memory problems. The research is published in the May 2, 2012, online issue of Neurology®, the medical journal of the American Academy of Neurology.
"While it's not easy to measure the level of beta-amyloid deposits in the brain in this type of study, it is relatively easy to measure the levels of beta-amyloid in the blood, which, to a certain degree, relates to the level in the brain," said study author Nikolaos Scarmeas, MD, MS, with Columbia University Medical Center in New York and a member of the American Academy of Neurology.
For the study, 1,219 people older than age 65, free of dementia, provided information about their diet for an average of 1.2 years before their blood was tested for the beta-amyloid. Researchers looked specifically at 10 nutrients, including saturated fatty acids, omega-3 and omega-6 polyunsaturated fatty acids, mono-unsaturated fatty acid, vitamin E, vitamin C, beta-carotene, vitamin B12, folate and vitamin D.
The study found that the more omega-3 fatty acids a person took in, the lower their blood beta-amyloid levels. Consuming one gram of omega-3 per day (equal to approximately half a fillet of salmon per week) more than the average omega-3 consumed by people in the study is associated with 20 to 30 percent lower blood beta-amyloid levels.
Other nutrients were not associated with plasma beta-amyloid levels. The results stayed the same after adjusting for age, education, gender, ethnicity, amount of calories consumed and whether a participant had the APOE gene, a risk factor for Alzheimer's disease.
"Determining through further research whether omega-3 fatty acids or other nutrients relate to spinal fluid or brain beta-amyloid levels or levels of other Alzheimer's disease related proteins can strengthen our confidence on beneficial effects of parts of our diet in preventing dementia," said Scarmeas.
Exercise Lowers Alzheimer's Risk, Even If You Start Late
Doing exercise every day can considerably reduce your risk of developing Alzheimer's disease, even if you start becoming physically active after 80 years of age, researchers from Rush University Medical Center reported in the journal Neurology. Increased physical activity may include becoming involved in daily chores, such as housework, the authors added.
Lead author, Dr. Aron S. Buchman, said:
"The results of our study indicate that all physical activities including exercise as well as other activities such as cooking, washing the dishes, and cleaning are associated with a reduced risk of Alzheimer's disease. These results provide support for efforts to encourage all types of physical activity even in very old adults who might not be able to participate in formal exercise, but can still benefit from a more active lifestyle.
This is the first study to use an objective measurement of physical activity in addition to self-reporting. This is important because people may not be able to remember the details correctly."
Dr. Buchman and team set out to measure total daily non-exercise and exercise physical activities among 716 seniors, with an average age of 82 years. They were all from the Rush Memory and Aging Project. None of them had any signs of dementia. They all wore a device which monitors their physical activity, called an actigraph. The device is worn on the dominant wrist. The participants wore the actigraph for 10 days.
The researchers recorded data on all their exercise and non-exercise physical activities. The seniors also underwent yearly cognitive tests (the study was ongoing) to measure their thinking abilities and memory. The study-participants also reported on their social and physical activities.
Over an average period of 41 months, 71 seniors developed AD (Alzheimer's disease).
Total exercise as well as exercise intensity affect Alzheimer's risk
The authors found that the 10% least physically active seniors in their study were 2.3 times as likely to develop Alzheimer's disease, compared to the 10% most active.
They also found that exercise intensity impacted on Alzheimer's risk. Those in the bottom 10% of physical activity intensity were 2.8 times as likely to develop AD, compared to those in the top 10%.
Dr. Buchman said:
"Since the actigraph was attached to the wrist, activities like cooking, washing the dishes, playing cards and even moving a wheelchair with a person's arms were beneficial. These are low-cost, easily accessible and side-effect free activities people can do at any age, including very old age, to possibly prevent Alzheimer's."
The researchers said that by 2030, the number of people in the USA over 65 years of age will double to 80 million.
Dr. Buchman said:
"Our study shows that physical activity, which is an easily modifiable risk factor, is associated with cognitive decline and Alzheimer's disease. This has important public health consequences."
Mind Games Help Healthy Older People Too
Cognitive training including puzzles, handicrafts and life skills are known to reduce the risk, and help slow down the progress, of dementia amongst the elderly. A new study published in BioMed Central's open access journal BMC Medicine showed that cognitive training was able to improve reasoning, memory, language and hand eye co-ordination of healthy, older adults.
It is estimated that by 2050 the number of people over 65 years old will have increased to 1.1 billion worldwide, and that 37 million of these will suffer from dementia. Research has already shown that mental activity can reduce a person's risk of dementia but the effect of mental training on healthy people is less well understood. To address this researchers from China have investigated the use of cognitive training as a defence against mental decline for healthy older adults who live independently.
To be recruited onto the trial participants had to be between 65 and 75 years old, and have good enough eyesight, hearing, and communication skills, to be able to complete all parts of the training. The hour long training sessions occurred twice a week, for 12 weeks, and the subjects were provided with homework. Training included a multi-approach system tackling memory, reasoning, problem solving, map reading, handicrafts, health education and exercise, or focusing on reasoning only. The effect of booster training, provided six months later, was also tested.
The results of the study were positive. Profs Chunbo Li and Wenyuan Wu who led the research explained, "Compared to the control group, who received no training, both levels of cognitive training improved mental ability, although the multifaceted training had more of a long term effect. The more detailed training also improved memory, even when measured a year later and booster training had an additional improvement on mental ability scores."
This study shows that cognitive training therapy may prevent mental decline amongst healthy older people and help them to continue independent living longer in their advancing years.
Low levels of omega-3 fatty acids may cause memory problems
A diet lacking in omega-3 fatty acids, nutrients commonly found in fish, may cause your brain to age faster and lose some of its memory and thinking abilities, according to a study published in the February 28, 2012, print issue of Neurology®, the medical journal of the American Academy of Neurology. Omega-3 fatty acids include the nutrients called docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA).
"People with lower blood levels of omega-3 fatty acids had lower brain volumes that were equivalent to about two years of structural brain aging," said study author Zaldy S. Tan, MD, MPH, of the Easton Center for Alzheimer's Disease Research and the Division of Geriatrics, University of California at Los Angeles.
For the study, 1,575 people with an average age of 67 and free of dementia underwent MRI brain scans. They were also given tests that measured mental function, body mass and the omega-3 fatty acid levels in their red blood cells.
The researchers found that people whose DHA levels were among the bottom 25 percent of the participants had lower brain volume compared to people who had higher DHA levels. Similarly, participants with levels of all omega-3 fatty acids in the bottom 25 percent also scored lower on tests of visual memory and executive function, such as problem solving and multi-tasking and abstract thinking.
Overeating may double risk of memory loss
New research suggests that consuming between 2,100 and 6,000 calories per day may double the risk of memory loss, or mild cognitive impairment (MCI), among people age 70 and older. The study was released today and will be presented at the American Academy of Neurology's 64th Annual Meeting in New Orleans April 21 to April 28, 2012. MCI is the stage between normal memory loss that comes with aging and early Alzheimer's disease.
"We observed a dose-response pattern which simply means; the higher the amount of calories consumed each day, the higher the risk of MCI," said study author Yonas E. Geda, MD, MSc, with the Mayo Clinic in Scottsdale, Arizona and a member of the American Academy of Neurology.
The study involved 1,233 people between the ages of 70 and 89 and free of dementia residing in Olmsted County, Minn. Of those, 163 had MCI. Participants reported the amount of calories they ate or drank in a food questionnaire and were divided into three equal groups based on their daily caloric consumption. One-third of the participants consumed between 600 and 1,526 calories per day, one-third between 1,526 and 2,143 and one-third consumed between 2,143 and 6,000 calories per day.
The odds of having MCI more than doubled for those in the highest calorie-consuming group compared to those in the lowest calorie-consuming group. The results were the same after adjusting for history of stroke, diabetes, amount of education, and other factors that can affect risk of memory loss. There was no significant difference in risk for the middle group.
"Cutting calories and eating foods that make up a healthy diet may be a simpler way to prevent memory loss as we age," said Geda.
Morning Exercise Better
Waking later and being active later put people at greater risk of dementia
Older women with weaker circadian rhythms, who are less physically active or are more active later in the day are more likely to develop dementia or mild cognitive impairment than women who have a more robust circadian rhythm or are more physically active earlier in the day. That’s the finding of a new study in the latest issue of the Annals of Neurology.
“We’ve known for some time that circadian rhythms, what people often refer to as the “body clock”, can have an impact on our brain and our ability to function normally,” says Greg Tranah, PhD., a scientist at the California Pacific Medical Center Research Institute – part of the Sutter Health network – and the lead author of the study. “What our findings suggest is that future interventions such as increased physical activity or using light exposure interventions to influence circadian rhythms, could help influence cognitive outcomes in older women.”
The researchers collected data on activity and circadian rhythm from 1,282 healthy women, all over the age of 75, who were taking part in the Study of Osteoporotic Fractures. All the women underwent a series of neuropsychological tests to ensure they had no evidence of cognitive or brain problems. At the end of five years 15 percent of the women had developed dementia and 24 percent had some form of mild cognitive impairment (MCI). Those women who had weaker circadian rhythm activity, lower levels of activity, or whose peak level of activity was later in the day, were at highest risk of developing dementia or MCI.
“This was not a small difference, but a rather sizable, statistically significant one,” says Tranah. “Those who had the later wake times, whose activity was later in the day, were 80 percent more likely to develop MCI or dementia compared to women who had earlier wake times and earlier activity.”
Circadian rhythms play an important role in the control of sleep-wake cycles and there is considerable evidence to show they also play a role in regulating certain brain functions, such as alertness, learning and memory. As people get older the activity level of those rhythms – how strong they are - often change, bringing with it changes in sleep patterns and levels of physical activity.
“To our knowledge this is the first study to show such a strong connection between circadian activity rhythm and the subsequent development of dementia or MCI,” says Tranah. “The reasons why this is so are not yet clear. The changes in circadian rhythm may directly influence the onset of dementia or MCI, or the decrease in activity may be a consequence, a warning sign if you like, that changes are already taking place in the brain. Identifying what the reason is could help us develop therapies to delay, or slow down, the development of brain problems in the elderly.”
In an accompanying commentary in the journal, Andrew Lim and Clifford Saper of the Department of Neurology at Harvard Medical School, say the study “represents a significant advance” in understanding the connection between circadian rhythm activity and dementia. “By showing that variations in rest-activity patterns precede the development of cognitive impairment and dementia, Tranah and colleagues have identified both a novel predictor of and a potential therapeutic target for incident cognitive deterioration and dementia.”
Eating fish reduces risk of Alzheimer's disease
People who eat baked or broiled fish on a weekly basis may be improving their brain health and reducing their risk of developing mild cognitive impairment (MCI) and Alzheimer's disease, according to a study presented today at the annual meeting of the Radiological Society of North America (RSNA).
"This is the first study to establish a direct relationship between fish consumption, brain structure and Alzheimer's risk," said Cyrus Raji, M.D., Ph.D., from the University of Pittsburgh Medical Center and the University of Pittsburgh School of Medicine. "The results showed that people who consumed baked or broiled fish at least one time per week had better preservation of gray matter volume on MRI in brain areas at risk for Alzheimer's disease."
Alzheimer's disease is an incurable, progressive brain disease that slowly destroys memory and cognitive skills. According to the National Institute on Aging, as many as 5.1 million Americans may have Alzheimer's disease. In MCI, memory loss is present but to a lesser extent than in Alzheimer's disease. People with MCI often go on to develop Alzheimer's disease.
For the study, 260 cognitively normal individuals were selected from the Cardiovascular Health Study. Information on fish consumption was gathered using the National Cancer Institute Food Frequency Questionnaire. There were 163 patients who consumed fish on a weekly basis, and the majority ate fish one to four times per week. Each patient underwent 3-D volumetric MRI of the brain. Voxel-based morphometry, a brain mapping technique that measures gray matter volume, was used to model the relationship between weekly fish consumption at baseline and brain structure 10 years later. The data were then analyzed to determine if gray matter volume preservation associated with fish consumption reduced risk for Alzheimer's disease. The study controlled for age, gender, education, race, obesity, physical activity, and the presence or absence of apolipoprotein E4 (ApoE4), a gene that increases the risk of developing Alzheimer's.
Gray matter volume is crucial to brain health. When it remains higher, brain health is being maintained. Decreases in gray matter volume indicate that brain cells are shrinking.
The findings showed that consumption of baked or broiled fish on a weekly basis was positively associated with gray matter volumes in several areas of the brain. Greater hippocampal, posterior cingulate and orbital frontal cortex volumes in relation to fish consumption reduced the risk for five-year decline to MCI or Alzheimer's by almost five-fold.
"Consuming baked or broiled fish promotes stronger neurons in the brain's gray matter by making them larger and healthier," Dr. Raji said. "This simple lifestyle choice increases the brain's resistance to Alzheimer's disease and lowers risk for the disorder."
The results also demonstrated increased levels of cognition in people who ate baked or broiled fish.
"Working memory, which allows people to focus on tasks and commit information to short-term memory, is one of the most important cognitive domains," Dr. Raji said. "Working memory is destroyed by Alzheimer's disease. We found higher levels of working memory in people who ate baked or broiled fish on a weekly basis, even when accounting for other factors, such as education, age, gender and physical activity."
Eating fried fish, on the other hand, was not shown to increase brain volume or protect against cognitive decline.
More on Alzheimer's:
According to statistics from the National Institute on Aging, Alzheimer’s disease is the most common form of dementia in older people. Alzheimer’s is a progressive brain disease; it is irreversible and causes a decline in memory and cognitive skills.
Alzheimer’s disease is the seventh leading cause of death in the United States. It is the only cause of death among the top 10 that cannot be prevented, cured or even significantly arrested. Two-thirds of people over the age of 65 who have the disease are women. This is a startling statistic, and one that requires increased attention and research.
“Clearly, this is an illness of women more than men,” said Victor Henderson, MD, MS, Professor of Epidemiology and Neurology and Neurological Sciences at Stanford University. “In part, it has to do with the fact that women live longer than men. There are real differences in longevity.”
Researchers have long studied the relationship between the hormone estrogen and Alzheimer's disease, but the results have been inconclusive thus far. “There are other risk factors that may come into play,” said Henderson, “which can further explain why women may be predisposed to Alzheimer’s disease.” Some of these factors include: family history, genetics, and some evidence suggests heart disease.
One of the first signs of Alzheimer’s disease may be forgetfulness and difficulty remembering newly learned information. But the disease gradually gets worse. According to the National Alzheimer’s Association in Chicago, other symptoms develop over time and may include:
• Challenges in planning or problem solving.
• Difficulty completing familiar tasks at home, at work, or at leisure.
• Confusion with time or place.
• Trouble understanding visual images and spatial relationships.
• New problems with words in speech or writing.
• Misplacing objects and losing the ability to retrace steps.
• Decreased or poor judgment.
• Withdrawal from work or social activities.
• Changes in mood and personality.
Reducing iron may lower age-related brain disease risk
The human body has a love-hate relationship with iron. Just the right amount is needed for proper cell function, yet too much is associated with brain diseases like Alzheimer's and Parkinson's.
Science knows that men have more iron in their bodies and brains than women. These higher levels may be part of the explanation for why men develop these age-related neurodegenerative diseases at a younger age.
But why do women have less iron in their systems than men? One possible explanation for the gender difference is that during menstruation, iron is eliminated through the loss of blood.
Now, a new study by UCLA researchers confirms this suspicion and suggests strategies to reduce excess iron levels in both men and women. Dr. George Bartzokis, a professor of psychiatry at the Semel Institute for Neuroscience and Human Behavior at UCLA, and colleagues compared iron levels in women who had undergone a hysterectomy before menopause -- and thus, did not menstruate and lose iron -- with levels in postmenopausal women who had not had a premenopausal hysterectomy. They found the women who had undergone a hysterectomy had higher levels of iron in their brains than the women who hadn't, and further, they had levels that were comparable to men.
The research is reported in the current online edition of the journal Neurobiology of Aging.
The researchers used an MRI technique that can measure the amount of ferritin iron in the brain (ferritin is a protein that stores iron). They examined 39 postmenopausal women, 15 of whom had undergone a premenopausal hysterectomy. They looked at several areas in the brain three white-matter regions and and five gray-matter regions. Fifty-four male subjects were also imaged for comparison.
The researchers found that among the women, the 15 who had undergone a hysterectomy had concentrations of iron in the white-matter regions of the brain's frontal lobe that did not differ from the men's levels. Further, both the women who had a hysterectomy and the men had significantly higher amounts of iron than the women who had not undergone a hysterectomy. (Gray matter areas showed slight increases that were not statistically significant.)
Hysterectomy is the most common non-obstetrical surgery among women in the United States, with one in three having had a hysterectomy by age 60, said Bartzokis, who is also a member of the UCLA Laboratory of Neuro Imaging and the UCLA Brain Research Institute.
The results of this study, he said, suggest that menstruation-associated blood loss may explain gender differences in brain iron. And of interest to both men and women, he said, is that it's possible that brain iron can be influenced by peripheral iron levels -- that is, iron levels throughout the body -- and may thus be a modifiable risk factor for age-related degenerative diseases.
"Iron accumulates in our bodies as we age," Bartzokis said, "and in the brain contributes to the development of abnormal deposits of proteins associated with several prevalent neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease and dementia with Lewy bodies. Higher brain iron levels in men may be part of the explanation for why men develop these age-related neurodegenerative diseases at a younger age, compared to women."
Bartzokis suggests it may be possible to reduce age-related brain iron accumulations by reducing the levels of iron throughout the body. This may have health benefits, especially in men, and may help counteract the negative effects of aging on the brain by reducing the iron available to catalyze, or speed up, damaging free-radical reactions.
There are a few ways body stores of iron can be reduced naturally, especially for premenopausal women. Menstruation leads to the elimination of iron through loss of blood. During pregnancy, iron is transferred from the woman to the fetus, and when women breast-feed, iron is transferred to the baby through the mother's milk.
"But there are things postmenopausal women and especially men can do to reduce their iron levels through relatively simple actions," Bartzokis said. "These include not overloading themselves with over-the-counter supplements that contain iron, unless recommended by their doctor; eating less red meat, which contains high levels of iron; donating blood; and possibly taking natural iron-chelating substances, molecules that bind to and remove iron, such as curcumin or green tea, that may have positive health consequences."
Small Amount of Exercise Could Protect Against Memory Loss
A new University of Colorado Boulder study shows that a small amount of physical exercise could profoundly protect the elderly from long-term memory loss that can happen suddenly following infection, illnesses or injury in old age.
In the study, CU-Boulder Research Associate Ruth Barrientos and her colleagues showed that aging rats that ran just over half a kilometer each week were protected against infection-induced memory loss.
"Our research shows that a small amount of physical exercise by late middle-aged rats profoundly protects against exaggerated inflammation in the brain and long-lasting memory impairments that follow a serious bacterial infection," said Barrientos of the psychology and neuroscience department.
The results of the study will appear in the Aug. 10 edition of The Journal of Neuroscience.
"Strikingly, this small amount of running was sufficient to confer robust benefits for those that ran over those that did not run," Barrientos said. "This is an important finding because those of advanced age are more vulnerable to memory impairments following immune challenges such as bacterial infections or surgery. With baby boomers currently at retirement age, the risk of diminished memory function in this population is of great concern. Thus, effective noninvasive therapies are of substantial clinical value."
Past research has shown that exercise in humans protects against declines in cognitive function associated with aging and protects against dementia. Researchers also have shown that dementia is often preceded by bacterial infections, such as pneumonia, or other immune challenges.
"To the best of our knowledge, this is the first study to show that voluntary exercise in rats reduces aging-induced susceptibility to the cognitive impairments that follow a bacterial infection, and the processes thought to underlie these impairments," Barrientos said.
In the study, the researchers found that rats infected with E. coli bacteria experienced detrimental effects on the hippocampus, an area of the brain that mediates learning and memory.
Monounsaturated Fatty Acids = Less Cognitive Decline
A diet high in monounsaturated fatty acids may be associated with less cognitive decline in older healthy women, according to a study published in the Journal of the American Geriatrics Society. Previous research has linked cognitive decline with cardiovascular disease, and certain types of dietary fatty acids (saturated and trans) are a known risk factor for cardiovascular disease. However, in this study, no association was found between cognitive decline and saturated or trans fatty acids. Monounsaturated fats are found in olive and canola oils, and saturated fats are found in coconut and palm oils as well as in butter, cheese, milk, and fatty meats. Trans fats are found in some margarines, commercial baked goods, and other foods made with or fried in partially hydrogenated oil.
Researchers analyzed the dietary intake of 482 women aged 60 and older from a food frequency questionnaire, and assessed their cognitive function—memory, vision, executive function, language, and attention—upon enrollment and again after 3 years. The study is part of a larger observational study that examined associations between dietary and lifestyle factors and cognitive function in older women without dementia.
The researchers found that a higher intake of dietary monounsaturated fatty acids was associated with less cognitive decline over a 3-year period. Further, after testing for associations between monounsaturated fatty acids and individual components of cognitive function, the researchers found that greater intake of monounsaturated fatty acids was associated with less decline in visual-spatial ability and memory after adjusting for other factors (i.e., age, education, reading ability). In addition, higher intakes of saturated fatty acids, trans-fatty acids, and dietary cholesterol were not associated with cognitive decline after adjusting for other factors.
The researchers noted that monounsaturated fatty acids have anti-inflammatory effects and suggested that these effects may provide one explanation for their protection against cognitive decline (as chronic inflammation appears to be one contributor to Alzheimer’s disease). Limitations of this observational analysis include the small sample size and the use of a study population consisting primarily of healthy, educated Caucasian women, which the researchers noted may limit the generalizability of findings to other populations.
Previous research has shown that immune cells of the brain, called microglia, become more reactive with age. When the older rats in the study encountered a bacterial infection, these immune cells released inflammatory molecules called cytokines in an exaggerated and prolonged manner.
"In the current study we found that small amounts of voluntary exercise prevented the priming of microglia, the exaggerated inflammation in the brain, and the decrease of growth factors," Barrientos said.
The next step of this research is to examine the role that stress hormones may play in sensitizing microglia, and whether physical exercise slows these hormones in older rats, she said.
Link between high cholesterol and Alzheimer's disease
People with high cholesterol may have a higher risk of developing Alzheimer's disease, according to a study published in the September 13, 2011, issue of Neurology®, the medical journal of the American Academy of Neurology.
"We found that high cholesterol levels were significantly related to brain plaques associated with Alzheimer's disease," said study author Kensuke Sasaki, MD, PhD, of Kyushu University in Fukuoka, Japan.
For the study, the cholesterol levels were tested for 2,587 people age 40 to 79 who had no signs of Alzheimer's disease. Then they examined 147 autopsied people who died after a long observation period (10 to 15 years). Of those, 50 people, or 34 percent, had been diagnosed with dementia before death.
The autopsies looked for plaques and tangles in the brain, both known to be trademark signs of Alzheimer's disease. Plaques are an accumulation of a form of the protein amyloid, which occurs between nerve cells. Tangles are an accumulation of a different protein, called tau, which occurs inside nerve cells.
People with high cholesterol levels, defined by a reading of more than 5.8 mmol/L, had significantly more brain plaques when compared to those with normal or lower cholesterol levels. A total of 86 percent of people with high cholesterol had brain plaques, compared with only 62 percent of people with low cholesterol levels.
The study found no link between high cholesterol and the tangles that develop in the brain with Alzheimer's disease.
In addition to high cholesterol increasing the risk of Alzheimer's disease, Sasaki previously found that insulin resistance, a sign of diabetes, may be another risk factor for brain plaques associated with Alzheimer's disease.
"Our study clearly makes the point that high cholesterol may contribute directly or indirectly to plaques in the brain," Sasaki said, "but failed treatment trials of cholesterol-lowering drugs in Alzheimer's disease means there is no simple link between lowering cholesterol and preventing Alzheimer's."
Aerobic Exercise May Reduce the Risk of Dementia
Any exercise that gets the heart pumping may reduce the risk of dementia and slow the condition’s progression once it starts, reported a Mayo Clinic study published this month in Mayo Clinic Proceedings. Researchers examined the role of aerobic exercise in preserving cognitive abilities and concluded that it should not be overlooked as an important therapy against dementia.
The researchers broadly defined exercise as enough aerobic physical activity to raise the heart rate and increase the body’s need for oxygen. Examples include walking, gym workouts and activities at home such as shoveling snow or raking leaves.
“We culled through all the scientific literature we could find on the subject of exercise and cognition, including animal studies and observational studies, reviewing over 1,600 papers, with 130 bearing directly on this issue. We attempted to put together a balanced view of the subject,” says J. Eric Ahlskog, M.D., Ph.D., a neurologist at Mayo Clinic. “We concluded that you can make a very compelling argument for exercise as a disease-modifying strategy to prevent dementia and mild cognitive impairment, and for favorably modifying these processes once they have developed.”
The researchers note that brain imaging studies have consistently revealed objective evidence of favorable effects of exercise on human brain integrity. Also, they note, animal research has shown that exercise generates trophic factors that improve brain functioning, plus exercise facilitates brain connections (neuroplasticity).
More research is needed on the relationship between exercise and cognitive function, the study’s authors say, but they encourage exercise, in general, especially for those with or worried about cognitive issues.
Alcohol and Dementia
Advising healthy people aged 65 years or older who are moderate, responsible drinkers to stop drinking or to markedly reduce their intake would not be in their best health interests, especially in terms of their risk of cardiovascular diseases. Forum reviewers thought that advice to lower limits of drinking for everyone in this age group is not based on reliable research, and would certainly not apply to all in this age group. Of more importance, the absolute risk for cardiovascular diseases increases markedly with age, and therefore the beneficial or protective effect of light to moderate drinking on cardiovascular diseases is greater in the elderly than in younger people.
Evidence is also accumulating that shows that the risk of Alzheimer's disease and other types of dementia is lower among moderate drinkers than among abstainers. Neurodegenerative disorders are key causes of disability and death among elderly people. Epidemiological studies have suggested that moderate alcohol consumption, may reduce the incidence of certain age-related neurological disorders including Alzheimer's disease. Regular dietary intake of flavonoid-rich foods and/or beverages has been associated with 50% reduction in the risk of dementia, a preservation of cognitive performance with ageing,a delay in the onset of Alzheimer's disease and a reduction in the risk of developing Parkinson's disease.
Mystery ingredient in coffee boosts protection against Alzheimer's disease
A yet unidentified component of coffee interacts with the beverage's caffeine, which could be a surprising reason why daily coffee intake protects against Alzheimer's disease. A new Alzheimer's mouse study by researchers at the University of South Florida found that this interaction boosts blood levels of a critical growth factor that seems to fight off the Alzheimer's disease process.
The findings appear in the early online version of an article to be published June 28 in the Journal of Alzheimer's Disease. Using mice bred to develop symptoms mimicking Alzheimer's disease, the USF team presents the first evidence that caffeinated coffee offers protection against the memory-robbing disease that is not possible with other caffeine-containing drinks or decaffeinated coffee.
Previous observational studies in humans reported that daily coffee/caffeine intake during mid-life and in older age decreases the risk of Alzheimer's disease. The USF researchers' earlier studies in Alzheimer's mice indicated that caffeine was likely the ingredient in coffee that provides this protection because it decreases brain production of the abnormal protein beta-amyloid, which is thought to cause the disease.
The new study does not diminish the importance of caffeine to protect against Alzheimer's. Rather it shows that caffeinated coffee induces an increase in blood levels of a growth factor called GCSF (granulocyte colony stimulating factor). GCSF is a substance greatly decreased in patients with Alzheimer's disease and demonstrated to improve memory in Alzheimer's mice. A just-completed clinical trial at the USF Health Byrd Alzheimer's Institute is investigating GCSF treatment to prevent full-blown Alzheimer's in patients with mild cognitive impairment, a condition preceding the disease. The results of that trial are currently being evaluated and should be known soon.
"Caffeinated coffee provides a natural increase in blood GCSF levels," said USF neuroscientist Dr. Chuanhai Cao, lead author of the study. "The exact way that this occurs is not understood. There is a synergistic interaction between caffeine and some mystery component of coffee that provides this beneficial increase in blood GCSF levels."
The researchers would like to identify this yet unknown component so that coffee and other beverages could be enriched with it to provide long-term protection against Alzheimer's.
In their study, the researchers compared the effects of caffeinated and decaffeinated coffee to those of caffeine alone. In both Alzheimer's mice and normal mice, treatment with caffeinated coffee greatly increased blood levels of GCSF; neither caffeine alone or decaffeinated coffee provided this effect. The researchers caution that, since they used only "drip" coffee in their studies, they do not know whether "instant" caffeinated coffee would provide the same GCSF response.
The boost in GCSF levels is important, because the researchers also reported that long-term treatment with coffee (but not decaffeinated coffee) enhances memory in Alzheimer's mice. Higher blood GCSF levels due to coffee intake were associated with better memory. The researchers identified three ways that GCSF seems to improve memory performance in the Alzheimer's mice. First, GCSF recruits stem cells from bone marrow to enter the brain and remove the harmful beta-amyloid protein that initiates the disease. GCSF also creates new connections between brain cells and increases the birth of new neurons in the brain.
"All three mechanisms could complement caffeine's ability to suppress beta amyloid production in the brain" Dr. Cao said, "Together these actions appear to give coffee an amazing potential to protect against Alzheimer's -- but only if you drink moderate amounts of caffeinated coffee."
Although the present study was performed in Alzheimer's mice, the researchers indicated that they've gathered clinical evidence of caffeine/coffee's ability to protect humans against Alzheimer's and will soon publish those findings.
Coffee is safe for most Americans to consume in the moderate amounts (4 to 5 cups a day) that appear necessary to protect against Alzheimer's disease. The USF researchers previously reported this level of coffee/caffeine intake was needed to counteract the brain pathology and memory impairment in Alzheimer's mice. The average American drinks 1 to 2 cups of coffee a day, considerably less than the amount the researchers believe protects against Alzheimer's.
"No synthetic drugs have yet been developed to treat the underlying Alzheimer's disease process" said Dr. Gary Arendash, the study's other lead author. "We see no reason why an inherently natural product such as coffee cannot be more beneficial and safer than medications, especially to protect against a disease that takes decades to become apparent after it starts in the brain."
The researchers believe that moderate daily coffee intake starting at least by middle age (30s – 50s) is optimal for providing protection against Alzheimer's disease, although starting even in older age appears protective from their studies. "We are not saying that daily moderate coffee consumption will completely protect people from getting Alzheimer's disease," Dr. Cao said. "However, we do believe that moderate coffee consumption can appreciably reduce your risk of this dreaded disease or delay its onset."
The researchers conclude that coffee is the best source of caffeine to counteract the cognitive decline of Alzheimer's because its yet unidentified component synergizes with caffeine to increase blood GCSF levels. Other sources of caffeine, such as carbonated drinks, energy drinks, and tea, would not provide the same level of protection against Alzheimer's as coffee, they said.
Coffee also contains many ingredients other than caffeine that potentially offer cognitive benefits against Alzheimer's disease. "The average American gets most of their daily antioxidants intake through coffee," Dr. Cao said. "Coffee is high in anti-inflammatory compounds that also may provide protective benefits against Alzheimer's disease."
An increasing body of scientific literature indicates that moderate consumption of coffee decreases the risk of several diseases of aging, including Parkinson's disease, Type II diabetes and stroke. Just within the last few months, new studies have reported that drinking coffee in moderation may also significantly reduce the risk of breast and prostate cancers.
"Now is the time to aggressively pursue the protective benefits of coffee against Alzheimer's disease," Dr. Arendash said. "Hopefully, the coffee industry will soon become an active partner with Alzheimer's researchers to find the protective ingredient in coffee and concentrate it in dietary sources."
New Alzheimer's diagnostic guidelines, now encompassing the full continuum of the disease from no overt symptoms to mild impairment to clear cognitive decline, could double the number of Americans with some form of the disease to more than 10 million. With the baby-boomer generation entering older age, these numbers will climb even more unless an effective preventive measure is identified.
"Because Alzheimer's starts in the brain several decades before it is diagnosed, any protective therapy would obviously need to be taken for decades," Dr. Cao said. "We believe moderate daily consumption of caffeinated coffee is the best current option for long-term protection against Alzheimer's memory loss. Coffee is inexpensive, readily available, easily gets into the brain, appears to directly attack the disease process, and has few side-effects for most of us."
According to the researchers, no other Alzheimer's therapy being developed comes close to meeting all these criteria.
"Aside from coffee, two other lifestyle choices -- physical and cognitive activity -- appear to reduce the risk of dementia. Combining regular physical and mental exercise with moderate coffee consumption would seem to be an excellent multi-faceted approach to reducing risk or delaying Alzheimer's," Dr. Arendash said. "With pharmaceutical companies spending millions of dollars trying to develop drugs against Alzheimer's disease, there may very well be an effective preventive right under our noses every morning – caffeinated coffee."
Dietary changes appear to lower risk of Alzheimer's disease
Following a low–saturated fat and low–glycemic index diet appears to modulate the risk of developing dementia that proceeds to Alzheimer’s disease (AD), and making a switch to this dietary pattern may provide some benefit to those who are already experiencing cognitive difficulty, according to a report in the June issue of Archives of Neurology, one of the JAMA/Archives journals.
Previous research has suggested multiple links between diet and cognitive ability, the authors note as background information. Health conditions in which insulin resistance (the body’s inability to use insulin effectively) is a factor—obesity, type 2 diabetes, cardiovascular disease and high cholesterol levels—have also been associated with “pathological brain aging.” However, studies of specific foods have not found conclusive evidence of an influence on Alzheimer’s risk. “Thus,” the authors write, “a more promising approach to the study of dietary factors in AD might entail the use of whole-diet interventions, which have greater ecologic validity and preserve the nutritional milieu in which fat and carbohydrate consumption occurs.”
Jennifer L. Bayer-Carter, M.S., from Veterans Affairs Puget Sound Health Care System, Seattle, and colleagues sought to compare a high–saturated fat/high–simple carbohydrate diet (a macronutrient pattern associated with type 2 diabetes and insulin resistance) with a low–saturated fat/low–simple carbohydrate diet; the interventions were named HIGH and LOW, respectively. The authors evaluated the effects of these diets in 20 older adults who were healthy and 29 older adults who had amnestic mild cognitive impairment (aMCI), meaning they experienced some memory problems; the latter condition is often considered a precursor to AD. In a four-week randomized, controlled trial, 24 participants followed the HIGH diet and 25 followed the LOW diet. The researchers studied participants’ performance on memory tests as well as their levels of biomarkers (biological substances indicative of AD), such as insulin, cholesterol, blood glucose levels, blood lipid levels and components of cerebrospinal fluid (CSF).
Results of the study were different for the group that had aMCI and the group of healthy participants. In the latter group, the LOW diet decreased some CSF biomarkers of AD as well as total cholesterol levels. However, among individuals with aMCI, the LOW diet increased levels of these biomarkers. Some changes to biomarkers, such as CSF insulin levels, were observed in both groups. Additionally, the LOW diet improved performance on delayed visual recall tests for both healthy and memory-impaired participants, but did not affect scores on other cognitive measures.
The findings indicate that “for healthy adults, the HIGH diet moved CSF biomarkers in a direction that may characterize a presymptomatic stage of AD,” explain the authors. They believe that the different results of the unhealthy diet in participants with aMCI may be due to the diet’s short duration. “The therapeutic effects of longer-term dietary intervention may be a promising avenue of exploration,” the authors conclude. “In addition, identification of the pathophysiologic changes underlying dietary effects may reveal important therapeutic targets that can be modulated through targeted dietary or pharmacologic intervention.”
Higher levels of social activity decrease the risk of cognitive decline
If you want to keep your brain healthy, it turns out that visiting friends, attending parties, and even going to church might be just as good for you as crossword puzzles.
According to research conducted at Rush University Medical Center, frequent social activity may help to prevent or delay cognitive decline in old age. The study has just been posted online in the Journal of the International Neuropsychological Society.
The researchers were especially careful in their analysis to try to rule out the possibility that cognitive decline precedes, or causes, social isolation, and not the reverse.
"It's logical to think that when someone's cognitive abilities break down, they are less likely to go out and meet friends, enjoy a camping trip, or participate in community clubs. If memory and thinking capabilities fail, socializing becomes difficult," said lead researcher Bryan James, PhD, postdoctoral fellow in the epidemiology of aging and dementia in the Rush Alzheimer's Disease Center. "But our findings suggest that social inactivity itself leads to cognitive impairments."
The study included 1,138 older adults with a mean age of 80 who are participating in the Rush Memory and Aging Project, an ongoing longitudinal study of common chronic conditions of aging. They each underwent yearly evaluations that included a medical history and neuropsychological tests.
Social activity was measured based on a questionnaire that asked participants whether, and how often, in the previous year they had engaged in activities that involve social interaction—for example, whether they went to restaurants, sporting events or the teletract (off-track betting) or played bingo; went on day trips or overnight trips; did volunteer work; visited relatives or friends; participated in groups such as the Knights of Columbus; or attended religious services.
Cognitive function was assessed using a battery of 19 tests for various types of memory (episodic, semantic and working memory), as well as perceptual speed and visuospatial ability.
At the start of the investigation, all participants were free of any signs of cognitive impairment. Over an average of five years, however, those who were more socially active showed reduced rates of cognitive decline. On average, those who had the highest levels of social activity (the 90th percentile) experienced only one quarter of the rate of cognitive decline experienced by the least socially active individuals. Other variables that might have accounted for the increase in cognitive decline—such as age, physical exercise, and health—were all ruled out in the analysis.
Alcohol consumption helps stave off dementia
Experts agree that long-term alcohol abuse is detrimental to memory function and can cause neuro-degenerative disease. However, according to a study published in Age and Ageing by Oxford University Press today, there is evidence that light-to-moderate alcohol consumption may decrease the risk of cognitive decline or dementia.
Estimates from various studies have suggested the prevalence of alcohol-related dementia to be about 10% of all cases of dementia. Now researchers have found after analyzing 23 longitudinal studies of subjects aged 65 years and older that the impact of small amounts of alcohol was associated with lower incidence rates of overall dementia and Alzheimer dementia, but not of vascular dementia and cognitive decline. It is still an open question whether different alcoholic beverages, such as beer, wine, and spirits, all have a similar effect. Some studies have shown a positive effect of wine only, which may be due either to the level of ethanol, the complex mixture that comprises wine, or to the healthier life-style ascribed to wine drinkers.
A total of 3,327 patients were interviewed in their homes by trained investigators (physicians, psychologists, gerontologists) and reassessed one and a half years and three years later. Information on the cognitive status of those who had died in the interim was collected from family members, caregivers or primary care physicians.
Among the 3,327 patients interviewed at baseline, 84.8% (n=2,820) could be personally interviewed one and a half years later and 73.9% (n=2,460) three years later. For the vast majority of subjects who could not be personally interviewed, systematic assessments (follow-up 1: 482; follow-up 2: 336) focusing particularly on dementia could be obtained from GPs, relatives or caregivers. Within three years, follow-up assessments were unavailable for only 49 subjects (1.5%). Proxy information could be obtained for 98.0% (n=295) of the 301 patients who had died in the interim. Since dementia is associated with a higher mortality rate, proxy information is particularly important in order to avoid underestimation of incident dementia cases.
At baseline there were 3,202 persons without dementia. Alcohol consumption information was available for 3,180 subjects:
50.0% were abstinent
24.8% consumed less than one drink (10 grams of alcohol) per day
12.8% consumed 10-19 grams of alcohol per day
12.4% consumed 20 or more grams per day
A small subgroup of 25 participants fulfilled the criteria of harmful drinking (>60 grams of alcohol per day for men, respectively >40 grams for women)
One man (>120 grams of alcohol per day) and one woman (>80 grams of alcohol per day) reported an extremely high consumption of alcohol
Among the consumers of alcohol almost half (48.6%) drank wine only
29.0% drank beer only
22.4% drank mixed alcohol beverages (wine, beer, or spirits)
Alcohol consumption was significantly associated with male gender, younger age, higher level of education, not living alone, and not being depressed.
The calculation of incident cases of dementia is based on 3,202 subjects who had no dementia at baseline. Within the follow-up period of three years:
217 cases of dementia (6.8%) were diagnosed, whereby 111 subjects (3.5%) suffered from Alzheimer dementia. Due to the relatively small numbers, other subgroups of dementia (vascular dementia: n=42; other specific dementia, e.g. dementia in Parkinson's disease, Lewy body dementia, alcohol dementia: n=14; dementia with unknown aetiology: n=50) were not considered in the following analyses.
Univariate and multivariate analyses revealed that alcohol consumption was significantly associated with a lower incidence of overall dementia and Alzheimer dementia. In line with a large-scale study also based on GP attenders aged 75 years and older, the study found that light-to-moderate alcohol consumption was associated with relatively good physical and mental health. This three-year follow-up study included, at baseline, only those subjects 75 years of age and older, the mean age was 80.2 years, much higher than that in most other studies.
Alcohol Abstinence = Increased Risk of Cognitive Impairment
Previous research regarding the association between alcohol consumption and dementia or cognitive impairment in later life suggests that mild to moderate alcohol consumption might be protective of dementia. However, most of the research has been conducted on subjects already rather elderly at the start of the follow-up.
A new study published in the December issue of the Journal of Alzheimer's Disease addresses this problem with a follow-up of more than two decades.
The study, conducted at the University of Turku, University of Helsinki and National Institute for Health and Welfare in Finland based on subjects from the Finnish Twin Cohort, shows that midlife alcohol consumption is related to the risk of dementia assessed some 20 years later. The study indicates that both abstainers and subjects consuming large amounts of alcohol have a greater risk for cognitive impairment than light drinkers.
"Our finding is significant as the changes typical of Alzheimer's disease -- the most common dementia syndrome -- are thought to start appearing two to three decades before clinical manifestation and therefore identification of early risk factors is imperative," states Jyri Virta, researcher at University of Turku, Finland.
Regularly drinking green tea could protect against Alzheimer's and other forms of dementia
Regularly drinking green tea could protect the brain against developing Alzheimer's and other forms of dementia, according to latest research by scientists at Newcastle University.
The study, published in the academic journal Phytomedicine, also suggests this ancient Chinese remedy could play a vital role in protecting the body against cancer.
Led by Dr Ed Okello, the Newcastle team wanted to know if the protective properties of green tea – which have previously been shown to be present in the undigested, freshly brewed form of the drink – were still active once the tea had been digested.
Digestion is a vital process which provides our bodies with the nutrients we need to survive. But, says Dr Okello, it also means that just because the food we put into our mouths is generally accepted to contain health-boosting properties, we can't assume these compounds will ever be absorbed by the body.
"What was really exciting about this study was that we found when green tea is digested by enzymes in the gut, the resulting chemicals are actually more effective against key triggers of Alzheimer's development than the undigested form of the tea," explains Dr Okello, based in the School of Agriculture, Food and Rural Development at Newcastle University.
"In addition to this, we also found the digested compounds had anti-cancer properties, significantly slowing down the growth of the tumour cells which we were using in our experiments."
As part of the research, the Newcastle team worked in collaboration with Dr Gordon McDougall of the Plant Products and Food Quality Group at the Scottish Crop Research Institute in Dundee, who developed technology which simulates the human digestive system.
It is this which made it possible for the team to analyse the protective properties of the products of digestion.
Two compounds are known to play a significant role in the development of Alzheimer's disease – hydrogen peroxide and a protein known as beta-amyloid.
Previous studies have shown that compounds known as polyphenols, present in black and green tea, possess neuroprotective properties, binding with the toxic compounds and protecting the brain cells.
When ingested, the polyphenols are broken down to produce a mix of compounds and it was these the Newcastle team tested in their latest research.
"It's one of the reasons why we have to be so careful when we make claims about the health benefits of various foods and supplements," explains Dr Okello.
"There are certain chemicals we know to be beneficial and we can identify foods which are rich in them but what happens during the digestion process is crucial to whether these foods are actually doing us any good."
Carrying out the experiments in the lab using a tumour cell model, they exposed the cells to varying concentrations of the different toxins and the digested green tea compounds.
Dr Okello explained: "The digested chemicals protected the cells, preventing the toxins from destroying the cells.
"We also saw them affecting the cancer cells, significantly slowing down their growth.
"Green tea has been used in Traditional Chinese medicine for centuries and what we have here provides the scientific evidence why it may be effective against some of the key diseases we face today."
The next step is to discover whether the beneficial compounds are produced during digestion after healthy human volunteers consume tea polyphenols. The team has already received funding from the Biotechnology and Biological Sciences Research Council (BBSRC) to take this forward.
Dr Okello adds: "There are obviously many factors which together have an influence on diseases such as cancer and dementia - a good diet, plenty of exercise and a healthy lifestyle are all important."
Walking slows progression of Alzheimer's
Walking may slow cognitive decline in adults with mild cognitive impairment (MCI) and Alzheimer's disease, as well as in healthy adults, according to a study presented today at the annual meeting of the Radiological Society of North America (RSNA).
"We found that walking five miles per week protects the brain structure over 10 years in people with Alzheimer's and MCI, especially in areas of the brain's key memory and learning centers," said Cyrus Raji, Ph.D., from the Department of Radiology at the University of Pittsburgh in Pennsylvania. "We also found that these people had a slower decline in memory loss over five years."
Alzheimer's disease is an irreversible, progressive brain disease that slowly destroys memory and cognitive skills. According to the National Institute on Aging, between 2.4 million and 5.1 million Americans have Alzheimer's disease. Based on current population trends, that number is expected to increase significantly over the next decade.
In cases of MCI, a person has cognitive or memory problems exceeding typical age-related memory loss, but not yet as severe as those found in Alzheimer's disease. About half of the people with MCI progress to Alzheimer's disease.
"Because a cure for Alzheimer's is not yet a reality, we hope to find ways of alleviating disease progression or symptoms in people who are already cognitively impaired," Dr. Raji said.
For the ongoing 20-year study, Dr. Raji and colleagues analyzed the relationship between physical activity and brain structure in 426 people, including 299 healthy adults (mean age 78), and 127 cognitively impaired adults (mean age 81), including 83 adults with MCI and 44 adults with Alzheimer's dementia.
Patients were recruited from the Cardiovascular Health Study. The researchers monitored how far each of the patients walked in a week. After 10 years, all patients underwent 3-D MRI exams to identify changes in brain volume.
"Volume is a vital sign for the brain," Dr. Raji said. "When it decreases, that means brain cells are dying. But when it remains higher, brain health is being maintained."
In addition, patients were given the mini-mental state exam (MMSE) to track cognitive decline over five years. Physical activity levels were correlated with MRI and MMSE results. The analysis adjusted for age, gender, body fat composition, head size, education and other factors.
The findings showed across the board that greater amounts of physical activity were associated with greater brain volume. Cognitively impaired people needed to walk at least 58 city blocks, or approximately five miles, per week to maintain brain volume and slow cognitive decline. The healthy adults needed to walk at least 72 city blocks, or six miles, per week to maintain brain volume and significantly reduce their risk for cognitive decline.
Over five years, MMSE scores decreased by an average of five points in cognitively impaired patients who did not engage in a sufficient level of physical activity, compared with a decrease of only one point in patients who met the physical activity requirement.
"Alzheimer's is a devastating illness, and unfortunately, walking is not a cure," Dr. Raji said. "But walking can improve your brain's resistance to the disease and reduce memory loss over time."
Vitamin B12 May Reduce Risk of Alzheimer's Disease
A new study shows that vitamin B12 may protect against Alzheimer's disease, adding more evidence to the scientific debate about whether the vitamin is effective in reducing the risk of memory loss.
The research will be published in the October 19, 2010, issue of Neurology®, the medical journal of the American Academy of Neurology.
"Our findings show the need for further research on the role of vitamin B12 as a marker for identifying people who are at increased risk of Alzheimer's disease," said study author Babak Hooshmand, MD, MSc, with Karolinska Institutet in Stockholm, Sweden. "Low levels of vitamin B12 are surprisingly common in the elderly. However, the few studies that have investigated the usefulness of vitamin B12 supplements to reduce the risk of memory loss have had mixed results."
For the seven-year study, researchers took blood samples from 271 Finnish people age 65 to 79 who did not have dementia at the start of the study. During that time, 17 people developed Alzheimer's disease. Blood samples were tested for levels for homocysteine, an amino acid associated with vitamin B12, and for levels of the active portion of the vitamin, called holotranscobalamin. Too much homocysteine in the blood has been linked to negative effects on the brain, such as stroke. However, higher levels of vitamin B12 can lower homocysteine.
The study found that for each micromolar increase in the concentration of homocysteine, the risk of Alzheimer's disease increased by 16 percent, whereas each picomolar increase in concentration of the active form of vitamin B12 reduced risk by two percent. The results stayed the same after taking into account other factors, such as age, gender, education, smoking status, blood pressure and body mass index. The addition of folate did not appear to raise or lower the risk of Alzheimer's disease.
"More research is needed to confirm these findings before vitamin B12 should be used solely as a supplement to help protect memory," said Hooshmand.
Vitamin B12 can be found in fish, poultry and other meat products.
Moderate drinking, especially wine, associated with better cognitive function
A large prospective study of 5033 men and women in the Tromsø Study in northern Norway has reported that moderate wine consumption is independently associated with better performance on cognitive tests. The subjects (average age 58 and free of stroke) were followed over 7 years during which they were tested with a range of cognitive function tests. Among women, there was a lower risk of a poor testing score for those who consumed wine at least 4 or more times over two weeks in comparison with those who drink < 1 time during this period The expected associations between other risk factors for poor cognitive functioning were seen, i.e. lower testing scores among people who were older, less educated, smokers, and those with depression, diabetes, or hypertension.
It has long been known that "moderate people do moderate things." The authors state the same thing: "A positive effect of wine . . . could also be due to confounders such as socio-economic status and more favourable dietary and other lifestyle habits.
The authors also reported that not drinking was associated with significantly lower cognitive performance in women. As noted by the authors, in any observational study there is the possibility of other lifestyle habits affecting cognitive function, and the present study was not able to adjust for certain ones (such as diet, income, or profession) but did adjust for age, education, weight, depression, and cardiovascular disease as its major risk factors.
The results of this study support findings from previous research on the topic: In the last three decades, the association between moderate alcohol intake and cognitive function has been investigated in 68 studies comprising 145,308 men and women from various populations with various drinking patterns. Most studies show an association between light to moderate alcohol consumption and better cognitive function and reduced risk of dementia, including both vascular dementia and Alzheimer's Disease.
Such effects could relate to the presence in wine of a number of polyphenols (antioxidants) and other micro elements that may help reduce the risk of cognitive decline with ageing. Mechanisms that have been suggested for alcohol itself being protective against cognitive decline include effects on atherosclerosis ( hardening of the arteries), coagulation ( thickening of the blood and clotting), and reducing inflammation ( of artery walls, improving blood flow).