Moderate alcohol consumption could reduce risk of death from dementia: Study

14-Dec-2015 - Last updated on 14-Dec-2015 at 14:18 GMT

One or two units of alcohol a day was associated with a 77% lower risk of death among Alzheimer's patients

Moderate drinking could reduce the risk of death for people with early stage Alzheimer’s disease, according to a study published in the British Medical Journal.

Drinking two or three units of alcohol a day was associated with a 77% lower risk of death in the study, when compared to patients who drank one or less units a day.

The researchers warn that the study does not provide a basis to either advise for or against alcohol consumption, but they call for further research into the effect of alcohol on the progression of Alzheimer’s disease.

Alcohol and the development of dementia

Moderate drinking has been linked to a lower risk of heart disease and stroke. The researchers wanted to see if the same association could be applied to people with dementia.

Previous studies have also looked at the relationship between alcohol and the risk of developing dementia. However, the researchers believe they are the first to show an association between alcohol and mortality in people who have already been diagnosed with Alzheimer’s.

The study took data from 321 participants in the Danish Alzheimer’s Intervention Study, who had early stage Alzheimer’s disease, and whose alcohol consumption was recorded by care-givers.

Consuming two to three units of alcohol a day was associated with a 77% lower risk of death, when compared to those who drank one or less alcohol units a day.

There was no difference between those who drank no alcohol or more than three units a day, compared to those who drank one or fewer units.

People who drink in moderation may have a better social network – a factor which has been linked to improved quality and possibly length of life, say the researchers.

Alcohol: neurotoxic effects?

Health professionals have been quick to assume that alcohol could be harmful for patients with Alzheimer’s, say the researchers.

“Considering that Alzheimer’s Disease is a neurodegenerative disorder and that alcohol has known neurotoxic effects, one could easily jump to the conclusion that alcohol is damaging for patients with Alzheimer’s,” wrote the authors.

“The aim of this study was to investigate whether the positive association between moderate alcohol intake and mortality shown in population-based studies on healthy subjects can be transferred to patients with mild Alzheimer’s.”

The study did not look at what types of alcohol were consumed, and so was not able to say whether there is a distinction between various forms such as wine, beer, or spirits.

“Regarding the importance of alcohol type when considering the risk of developing dementia, earlier studies have not been in agreement," continued the authors.
“Some have argued that only consumption of wine was associated with a lower risk of dementia, while other studies observed no difference between types of alcohol.

“When using ‘two to three units per day’ as the reference group, we found that those with moderate alcohol consumption had a significantly lower risk of mortality than subjects with high alcohol intake. This points in the direction that increased alcohol intake is only protective until a certain consumption level.”

Alzheimer’s Disease International estimates there are around 46.8m people worldwide with dementia, a figure set to reach 74.7m in 2030 and 131.5m in 2050.

Source: BMJ Open, December 11, 2015. doi:10.1136/bmjopen-2015-007851

Title: ‘Alcohol consumption and mortality in patients with mild Alzheimer's disease: a prospective cohort study’

Authors: S. Berntsen; J. Kragstrup; V. Siersma; G. Waldemar; F. B. Waldorff.