Understanding Dementia Risk and Alcohol Use – Neuroscience News

Summary: Researchers report that abstaining from drinking alcohol may actually increase the risk of dementia. Low to moderate alcohol consumption can help reduce the risk of dementia.

Source: BE CAREFUL

A recent study led by Dr. Louise Mewton at the UNSW Center for Healthy Brain Aging (CHeBA) has reignited the debate about whether low levels of alcohol consumption could be beneficial for health.

The review, published in Addictionshowed that abstaining completely from alcohol can actually increase the risk of dementia.

In recent decades, the estimated global prevalence of dementia has nearly tripled, from 20.2 million in 1990 to 57.4 million in 2019. By 2050, there will be 152 million people with of dementia in the world.

According to the researchers, reducing risk factors is a fundamental strategy for preventing dementia, especially given the lack of disease-modifying treatments for dementia. A 2020 report by the Lancet Commission for Dementia Prevention, Intervention and Care estimated that 40% of dementia cases worldwide could be prevented or delayed if 12 key modifiable risk factors for dementia were eliminated. , with excessive or harmful drinking in midlife newly listed as one such factor.

Dr Mewton, who leads the risk factors group at CHeBA, said the inclusion of alcohol as a key risk factor for dementia was based on consistent and strong evidence that chronic excessive drinking of alcohol is associated with dementia and cognitive decline.

“There is controversy over the impact of more moderate levels of alcohol consumption on the incidence of dementia. Even low levels of alcohol consumption have been associated with poorer health outcomes, including a increased risk of cancer.

“They have also been associated with atrophy in key brain regions linked to dementia, such as the hippocampus.”

However, in this international study of nearly 25,000 adults over the age of 65 living in the community, including in the United States, Australia, Europe, Brazil and the Republic of Congo, it was consistently shown that the Alcohol abstention was associated with a higher risk of dementia. .

“Our data comes from 15 studies of healthy aging on six continents and a robust assessment of alcohol use and dementia,” Dr Mewton said.

“During the study period, 2,124 adults developed dementia. What we can conclude from our study is that it does not seem necessary to intervene in older adults who currently drink lightly to moderately if preventing dementia is the ultimate goal.

Researchers found that people who drank up to four Australian standard drinks a day had a lower risk of dementia compared to people who didn’t drink at all. The lower risk of dementia associated with alcohol use was evident beyond the effects of demographic characteristics (such as age, gender, and education), as well as clinical characteristics (such as history of stroke, diabetes and hypertension).

“It has been suggested that the increased risk of dementia associated with abstinence may be the result of the inclusion of former drinkers who quit drinking due to other health conditions or the onset of cognitive problems. “

“However, our study found an increased risk of dementia even after excluding former drinkers from the analysis and after adjusting for relevant demographic and clinical characteristics,” Dr. Mewton said.

Despite this, there may be other characteristics such as social activity that could drive the apparent protective effect of alcohol against dementia, rather than alcohol consumption per se.

Lead author and co-director of CHeBA, Professor Perminder Sachdev, said that while light to moderate alcohol consumption may be associated with a reduced risk of dementia, even low levels of alcohol consumption have been associated with reduced risk of dementia. reduced brain volume, gray matter atrophy and increased white matter hyperintensities. indicating that even low alcohol consumption is harmful to the brain.

About this dementia research news

Author: Press office
Source: BE CAREFUL
Contact: Press office – CHeBA
Image: Image is in public domain

Original research: Free access.
“The relationship between alcohol consumption and dementia in adults over the age of 60: a pooled analysis of prospective individual participant data from 15 international studies” by Louise Mewton et al. Addiction

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Summary

The relationship between alcohol consumption and dementia in adults over the age of 60: a combined analysis of prospective individual participant data from 15 international studies

Objective

Synthesize international findings on the alcohol-dementia relationship, including representation from low- and middle-income countries.

Methods

Meta-analysis of individual participant data from 15 prospective epidemiological cohort studies from countries on six continents. Cox regression studied the risk of dementia associated with alcohol consumption in people over the age of 60. Additional analyzes assessed the alcohol-dementia relationship in the sample stratified by gender and continent. Participants included 24,478 people living in the community with no history of dementia at baseline and at least one follow-up dementia assessment. The primary outcome was dementia from any cause, as determined by clinical interview.

Results

At baseline, the mean age across all studies was 71.8 years (SD=7.5, range=60–102 years), 14,260 (58.3%) were female, and 13,269 (54. 2%) were current drinkers. During the 151,636 person-years of follow-up, there were 2,124 incident cases of dementia (14.0 per 1,000 person-years). Compared to abstainers, the risk of dementia was lower in occasional patients. [hazard ratio (HR) = 0.78; 95% confidence interval (CI) = 0.68–0.89], light to moderate drinkers (HR = 0.78; 95% CI = 0.70 to 0.87) and moderate to heavy drinkers (HR = 0.62; 95% CI = 0.51 to 0.77) . There was no evidence of differences between lifelong abstainers and former drinkers in dementia risk ( RR = 0.98; 95% CI = 0.81–1.18). In dose-response analyses, moderate drinking up to 40 g/day was associated with a lower risk of dementia compared to lifelong abstinence. Among current drinkers, there was no consistent evidence of differences in dementia risk. The results were similar when the sample was stratified by gender. When analyzed at the continental level, there was considerable heterogeneity in the alcohol-dementia relationship.

conclusion

Abstinence from alcohol appears to be associated with an increased risk of dementia from all causes. Among current drinkers, there does not appear to be consistent evidence to suggest that the amount of alcohol consumed later in life is associated with dementia risk.