Moderate Alcohol Consumption - Cognitive Decline/Dementia Benefits

Beer Drinking May Be Protective against Alzheimer's

While most people will agree that excessive consumption of alcohol can have a detrimental effect on the brain, there is less agreement regarding the effects of light or moderate drinking. This includes concern and controversy surrounding the effects of drinking on the development of neurodegenerative diseases such as Alzheimer's (AD). This study investigated the association between consumption of different alcoholic beverages -- beer, wine, and spirits -- and one of the neuropathological signs of Alzheimer's disease, β-amyloid (Aβ) aggregation in the brain.

Researchers examined data from 125 males participating in the Helsinki sudden death autopsy series, who at the time of death were 35 to 70 years old. Consumption of alcohol, Aβ aggregation in the brain, and apolipoprotein E (APOE) genotype were assessed. Surviving relatives answered a questionnaire used to gather the drinking history of the deceased, and Aβ was observed by immunohistochemical staining of brain sections.

Findings suggest that beer consumption may protect against Aβ aggregation in the brain. The amount of alcohol consumed was not linked with Aβ aggregation, and neither was spirit or wine consumption. Given that the development of dementia occurs over several years and even decades, the authors call for additional studies to identify early and mid-life factors that may stimulate or protect against Aβ aggregation.

---

Journal Reference: Eloise H. Kok, Toni T. Karppinen, Teemu Luoto, Irina Alafuzoff, Pekka J. Karhunen. Beer Drinking Associates with Lower Burden of Amyloid Beta Aggregation in the Brain: Helsinki Sudden Death Series. Alcoholism: Clinical and Experimental Research,

Drinking 2 to 3 units of alcohol every day is linked to a reduced risk of death among people with early stage Alzheimer's disease

Drinking 2 to 3 units of alcohol every day is linked to a reduced risk of death among people with early stage Alzheimer's disease, finds research published in the online journal BMJ Open.

Moderate drinking has been associated with a lower risk of developing and dying from heart disease and stroke. But alcohol is known to damage brain cells, and given that dementia is a neurodegenerative disorder, drinking might be harmful in those with the condition.

The researchers therefore wanted to find out if the same potentially positive association between alcohol and a reduced risk of cardiovascular death could be applied to 321 people with early stage Alzheimer's disease, defined as a score of 20 or less on the Mini Mental State Exam (MMSE).
The research team analysed data originally collected on 330 people with early stage dementia or Alzheimer's disease and their primary carers from across Denmark as part of the Danish Alzheimer's Intervention Study (DAISY).

DAISY set out to assess the impact of a 12 month programme of psychosocial counselling and support, and tracked progress for three years afterwards, accumulating a considerable amount of data.
This included information on how much alcohol people with early stage dementia or Alzheimer's drank every day. Around one in 10 (8%) drank no alcohol and at the other end of the scale, around one in 20 (4%) drank more than 3 units daily.

Most of the sample (71%) drank 1 or fewer units a day; 17% drank 2-3 units.

During the monitoring period, 53 (16.5%) of those with mild Alzheimer's disease died. Consumption of 2-3 units of alcohol every day was associated with a 77% lowered risk of death compared with a tally of 1 or fewer daily units.

There was no significant difference in death rates among those drinking no alcohol or more than 3 units every day compared with those drinking 1 or fewer daily units.

These results held true after taking account of influential factors: gender, age, other underlying conditions, whether the individual lived alone or with their primary carer, educational attainment, smoking, quality of life, and MMSE result.

The researchers say there could be several explanations for the findings, including that people who drink moderately have a richer social network, which has been linked to improved quality, and possibly length, of life.

Another explanation may lie in the fact that the seemingly protective effect of alcohol may have been caused by reverse causality, whereby those drinking very little alcohol were in the terminal phase of their life, which would have artificially inflated the positive association.

In a bid to correct for this, the researchers re-analysed the data, omitting the first year of monitoring. But this made no difference to the findings.

"The results of our study point towards a potential, positive association of moderate alcohol consumption on mortality in patients with Alzheimer's disease. However, we cannot solely, on the basis of this study, either encourage or advise against moderate alcohol consumption in [these] patients," they caution.

They suggest that further research looking at the impact of alcohol on cognitive decline and disease progression in patients with mild Alzheimer's disease would be particularly informative.

Resveratrol (red wine) may help prevent age-related decline in memory

A compound found in common foods such as red grapes and peanuts may help prevent age-related decline in memory, according to new research published by a faculty member in the Texas A&M Health Science Center College of Medicine.

Ashok K. Shetty, Ph.D., a professor in the Department of Molecular and Cellular Medicine and Director of Neurosciences at the Institute for Regenerative Medicine, has been studying the potential benefit of resveratrol, an antioxidant that is found in the skin of red grapes, as well as in red wine, peanuts and some berries. 

Resveratrol has been widely touted for its potential to prevent heart disease, but Shetty and a team that includes other researchers from the health science center believe it also has positive effects on the hippocampus, an area of the brain that is critical to functions such as memory, learning and mood.
Because both humans and animals show a decline in cognitive capacity after middle age, the findings may have implications for treating memory loss in the elderly. Resveratrol may even be able to help people afflicted with severe neurodegenerative conditions such as Alzheimer's disease.

In a study published online Jan. 28, 2015 in Scientific Reports, Shetty and his research team members reported that treatment with resveratrol had apparent benefits in terms of learning, memory and mood function in aged rats. 

"The results of the study were striking," Shetty said. "They indicated that for the control rats who did not receive resveratrol, spatial learning ability was largely maintained but ability to make new spatial memories significantly declined between 22 and 25 months. By contrast, both spatial learning and memory improved in the resveratrol-treated rats."

Shetty said neurogenesis (the growth and development of neurons) approximately doubled in the rats given resveratrol compared to the control rats. The resveratrol-treated rats also had significantly improved microvasculature, indicating improved blood flow, and had a lower level of chronic inflammation in the hippocampus.

"The study provides novel evidence that resveratrol treatment in late middle age can help improve memory and mood function in old age," Shetty said. 

Light-to-moderate alcohol consumption: 35-45% lower risk of cognitive decline or dementia

Alzheimer's disease (AD) and other types of dementia are most common in the very elderly, and are associated with huge health costs. With a rapidly ageing population throughout the world, factors that affect the risk of cognitive decline and dementia are of great importance. A review paper published in Psychiatry Investig 2012;9:8-16 on the association between alcohol consumption and cognition in the elderly provides an excellent summary of the potential ways in which alcohol may affect cognitive function and the risk of dementia, both adversely and favourably as alcohol may have both a neuro toxic and neuro protective effect, depending on the dose and drinking pattern. Longitudinal and brain imaging studies in the elderly show that excessive alcohol consumption may increase the risk of cognitive dysfunction and dementia, but regular low to moderate alcohol intake may protect against cognitive decline and dementia and provide cardiovascular benefits.

Studies published from 1971 to 2011 related to alcohol and cognition in the elderly were reviewed using a PubMed search. At present, there are no proven agents to prevent cognitive decline or dementia, although a number of prospective epidemiologic studies have shown a lower risk of such conditions among light to moderate drinkers in comparison with non-drinkers. Other studies have found that beneficial effects are seen only among certain sub-groups of subjects. A recent meta-analysis by Peters et al of subjects over the age of 65 in longitudinal studies concluded that light-to-moderate alcohol consumption, in comparison with abstinence, was associated with approximately 35-45% lower risk of cognitive decline or dementia.

This paper provides a summary of what is known about the mechanisms by which alcohol consumption, especially heavy drinking, can be neurotoxic, and how light-to-moderate drinking may help protect against cognitive decline and dementia. The authors state that their intent is to determine if there is an "optimal pattern of drinking" that may protect the elderly against such conditions.

At present, the mechanisms by which the moderate intake of wine and other alcoholic beverages reduces the risk of cardiovascular diseases are much better defined than they are for cognition. Forum members agree with the authors that further research is needed to evaluate a potential role that alcohol may play in reducing the risk of dementia.

Forum members also agree that, at present, the specific mechanisms of such putative protection are not well defined, and it would be premature to recommend light-to-moderate drinking for reducing the risk of dementia. On the other hand, current biomedical data supports the concept that regular, moderate intake of ethanol is not simply less dangerous for cognitive function, but is positively protective. This is the same conclusion reached by epidemiologic studies."

Moderate drinking protects against Alzheimer's and cognitive impairment

Moderate social drinking significantly reduces the risk of dementia and cognitive impairment, according to an analysis of 143 studies by Loyola University Chicago Stritch School of Medicine researchers.

Researchers reviewed studies dating to 1977 that included more than 365,000 participants. Moderate drinkers were 23 percent less likely to develop cognitive impairment or Alzheimer's disease and other forms of dementia.

Wine was more beneficial than beer or spirits. But this finding was based on a relatively small number of studies, because most papers did not distinguish among different types of alcohol.

Results are reported in the journal Neuropsychiatric Disease and Treatment. The authors are Edward J. Neafsey, PhD. and Michael A. Collins, PhD., professors in the Department of Molecular Pharmacology and Therapeutics.

Heavy drinking (more than 3 to 5 drinks per day) was associated with a higher risk of cognitive impairment and dementia, but this finding was not statistically significant.

"We don't recommend that nondrinkers start drinking," Neafsey said. "But moderate drinking -- if it is truly moderate -- can be beneficial." Moderate drinking is defined as a maximum of two drinks per day for men and 1 drink per day for women.

Among the studies reviewed, 74 papers calculated the ratios of risk between drinkers and non-drinkers, while 69 papers simply stated whether cognition in drinkers was better, the same or worse than cognition in nondrinkers. Neafsey and Collins did a meta-analysis of the studies that calculated risk ratios and found that moderate drinkers were 23 percent less likely to develop dementia or cognitive decline.

Other findings:

• The protective effect of moderate drinking held up after adjusting for age, education, sex and smoking.
• There was no difference in the effects of alcohol on men and women.
• The beneficial effect of moderate drinking was seen in 14 of 19 countries, including the United States. In 3 of the remaining 5 countries, researchers also found a benefit, but it was not strong enough to be statistically significant.
• The findings were similar across different types of studies (longitudinal cohort studies, case-control studies and cross-sectional studies).

It is unknown why moderate drinking can have a beneficial effect. One theory suggests that the well-known cardiovascular benefits of moderate alcohol consumption, such as raising good HDL cholesterol, also can improve blood flow in the brain and thus brain metabolism.

A second possible explanation involves "sick quitters." According to this theory, nondrinkers have a higher risk of cognitive impairment and dementia because the group includes former heavy drinkers who damaged their brain cells before quitting. But the analysis by Neafsey and Collins did not support this explanation. They found that in studies that excluded former heavy drinkers, the protective effect of moderate drinking still held up.

Neafsey and Collins suggest a third possible explanation: Small amounts of alcohol might, in effect, make brain cells more fit. Alcohol in moderate amounts stresses cells and thus toughens them up to cope with major stresses down the road that could cause dementia.

For people who drink responsibly and in moderation, there's probably no reason to quit. But because of the potential for alcohol to be abused, Neafsey and Collins do not recommend that abstainers begin drinking.

The researchers note that there are other things besides moderate drinking that can reduce the risk of dementia, including exercise, education and a Mediterranean diet high in fruits, vegetables, cereals, beans, nuts and seeds. Even gardening has been shown to reduce the risk of dementia.

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 , 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 study published in the December, 2010 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.

In addition to total alcohol consumption, the authors were able to assess the effects of different drinking patterns. The study suggests that drinking large amounts of alcohol (defined as a bottle of wine or the equivalent) at a single occasion at least monthly is an independent risk factor for cognitive impairment. Such binge drinking doubles the risk of cognitive impairment even when total alcohol consumption was statistically controlled for.

Similarly, passing out because of heavy drinking on one occasion was also found to increase the development of subsequent cognitive impairment. Thus, it is not only the amount of alcohol, but also the pattern by which alcohol is consumed that affect the risk of cognitive impairment. The published study is among the first to report these effects.

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).

Moderate alcohol intake has cognitive benefits

A glass of wine here, a nightcap there –research out of Wake Forest University School of Medicine suggests that moderate alcohol intake offers long-term cognitive protection and reduces the risk of dementia in older adults.

The study was presented at the Alzheimer's Association 2009 International Conference on Alzheimer's Disease (ICAD), in Vienna.

While previous studies have shown that moderate alcohol intake, particularly wine, is linked with lower risk of heart attacks and dementia, most of the studies have been done in middle-aged people, and it has remained unclear if the benefits of alcohol also apply to older adults in general or to older adults who might already have some mild memory problems. This is the largest, longest U.S. study to look at the effects of regular alcohol intake on dementia in seniors, both with and without memory problems.

"As of yet, we still have no cure for Alzheimer's disease and other dementias, so it is important to look for things that might help people prevent the disease," said Kaycee Sink, M.D., M.A.S (Masters of Advanced Studies in clinical research), a geriatrician and senior author of the paper. Moderate alcohol intake has been linked to lower risk of heart attacks, stroke, dementia, and death in middle-aged adults, but there is still controversy about alcohol intake in older adults."

For the study, researchers began by examining and interviewing 3,069 individuals, 75 years or older and most without any memory or thinking problems, about their drinking habits. Participants were asked about beer, wine, and liquor. The investigators then categorized the individuals as abstainers (non-drinkers), light drinkers (one to seven drinks per week), moderate drinkers (eight to 14 drinks per week), or heavy drinkers (more than 14 drinks per week). All types of alcohol were included.

The study subjects were then examined and interviewed every six months for six years to determine changes in their memory or thinking abilities and to monitor who developed dementia.

Researchers found that individuals who had no cognitive impairment at the start of the study and drank eight to 14 alcoholic beverages per week, or one to two per day, experienced an average 37 percent reduction in risk of developing dementia compared to individuals who did not drink at all and were classified as abstainers. The type of alcohol consumed did not matter.

For older adults who started the study with mild cognitive impairment, however, consumption of alcohol, at any amount, was associated with faster rates of cognitive decline. In addition, those who were classified in the heavy drinker category, consuming more than 14 drinks per week, were almost twice as likely to develop dementia during the study compared to non-drinkers with mild cognitive impairment.

"We were excited to see that even in older adults, moderate alcohol intake decreases the risk of dementia," Sink said. "It is important to note, however, that our study found a significantly higher risk of dementia for heavy drinkers who started the study with mild cognitive impairment."

The results are consistent with previous studies of middle-aged adults that suggest mild to moderate alcohol intake may reduce the risk of dementia, except in the case of individuals who already have mild to moderate cognitive impairment. The researchers' findings support current recommendations not to exceed one drink per day for women and two for men.

It is unclear from this study whether an abstainer who begins drinking moderately in his/her 70s will experience the same benefit or if the benefit is associated with a long pattern of moderate alcohol intake that continues on into old age.

"Our results suggest that older adults who are normal cognitively and drink moderately do not need to change their drinking behavior," Sink said. "If you have mild cognitive impairment however, it might benefit you to restrict your drinking and certainly not exceed one drink a day for women and two drinks a day for men.

"The participants in this study self-reported their alcohol intake at the start, but it is unusual for people to start drinking in their 70s, so we assume that the habits they reported at the start of the study reflect stable drinking habits," Sink added. "Without scientific data showing that it is beneficial, I wouldn't recommend that non-drinkers start drinking in their 70s.

"We are starting to make progress in understanding how to prevent and treat Alzheimer's and other dementias," she said. "It is a very exciting time to be involved in geriatrics research."

Moderate drinkers often have lower risks of Alzheimer's disease and other cognitive loss

Moderate drinkers often have lower risks of Alzheimer's disease and other cognitive loss, according to researchers who reviewed 44 studies.

In more than half of the studies, published since the 1990s, moderate drinkers of wine, beer and liquor had lower dementia risks than nondrinkers. In only a few studies were there increased risks.

"Alcohol is a two-edged sword," said Michael Collins, Ph.D., a professor and neuroscientist at Loyola University Chicago Stritch School of Medicine and lead author of the refereed report in the journal Alcoholism: Clinical and Experimental Research. "Too much is bad. But a little might actually be helpful."

Moderate alcohol consumption generally is defined as 1 drink or less per day for women and 1-2 drinks or less per day for men.

The article was published in the February 2009 issue of the journal.

"The pathological damage and vast social havoc from addiction to and abuse of alcohol are well known, and of necessity should continue to receive primary attention by doctors, scientific researchers and health professionals," Collins and colleagues write. "However, light-to-moderate responsible alcohol consumption "appears to carry certain health benefits."

Long-term alcohol abuse can cause memory loss and impair cognitive function. It's unknown why moderate alcohol use appears to have the opposite effect. One theory is that the well-known cardiovascular benefits of moderate alcohol consumption also can reduce the risk of mini strokes that cause dementia.

Collins and another Loyola professor, neuroscientist Edward Neafsey, Ph.D., suggest a second possible explanation. Small amounts of alcohol might, in effect, make brain cells more fit. Alcohol in moderate levels stresses cells and thus toughens them up to cope with major stresses down the road that could cause dementia.

For most people who drink responsibly and in moderation, there's probably no reason to quit. But because of the potential for alcohol to be abused, Collins and Neafsey do not recommend that abstainers begin drinking. The researchers note there are other things besides moderate drinking that can reduce the risk of dementia, including exercise, green tea, education and a Mediterranean diet high in fruits, vegetables, cereals, beans, nuts and seeds.

Red wine again linked to slowing Alzheimer's

A Mount Sinai School of Medicine study found giving mice with amyloid plaques red wine slows their memory loss and brain cell death - adding to a body of science linking compounds in the beverage to slowing the Alzheimer's disease-related symptom.

In the study - published in Federation of American Societies for Experimental Biology Journal - wine-drinking mice learned to escape from a maze significantly faster than mice drinking alcohol-spiked water or water.

The results could have implications for formulators in the production of supplements for age-related conditions.

According to the Alzheimers Society, there are nearly 18 million people in the world with dementia. Around 55 percent of those who suffer from dementia have Alzheimer's.

In the Mount Sinai study, the mice's wine intake was aligned to what is the equivalent of moderate consumption in humans - a five-ounce glass per day for women and two for men.

In the past, both alcohol and a red wine compound, resveratrol, have been linked to a reduction in the onset of dementia.

For several months, the Mount Sinai mice were given cabernet sauvignon or ethanol in their drinking water, while another group of mice drank plain water. All the mice had amyloid plaques in their brains that occur in humans with Alzheimer's disease.

The research team, led by Dr. Giulio Maria Pasinetti, assessed the mice's memory by testing their ability to get out of a maze. The wine-drinking mice were able to exit the maze significantly faster than those drinking alcohol-spiked water or water only, the scientists found.

The study only advocates moderate red wine consumption as part of an overall healthy lifestyle.