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 by Kim JW et al 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.