Moderate drinking may reduce death risk in early stages of Alzheimer's

London: Drinking two to three units of alcohol every day is linked to a reduced risk of death among people with early stage Alzheimer's disease, a new study has claimed. 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, according to the study published in the journal BMJ Open.

Researchers 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).

This included information on how much alcohol people with early stage dementia or Alzheimer's drank every day. Around one in 10 drank no alcohol and at the other end of the scale, around one in 20 drank more than three units daily. Most of the sample (71 per cent) drank one or fewer units a day and 17 per cent drank two to three units.

During the monitoring period, 53 (16.5 per cent) of those with mild Alzheimer's disease died. Consumption of two to three units of alcohol every day was associated with a 77 per cent lowered risk of death compared with a tally of one or fewer daily units. There was no significant difference in death rates among those drinking no alcohol or more than three units every day compared with those drinking one 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 said 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," researchers said.