Effects of drinking on late-life brain and cognition

Abstract

Alcohol consumption is common in Western countries and has been increasing in older adults. Latest figures from Great Britain suggest 75% of those over 65 years drink, an increase from 71% 10 years ago. Chronic heavy intake is a well-established cause of brain atrophy and dementia, with a recent long-term prospective study from the USA reporting a doubling of the odds of later severe memory impairment in those with a history of an alcohol use disorder. Drinking of moderate amounts has been reported to be protective for brain health in a number of epidemiological studies, including some claims of possibly reducing dementia risk. Rigorous recent research has questioned this belief, with new evidence of harmful associations in moderate drinkers compared with abstainers. This has raised suspicion that reported protective effects of moderate drinking were due to confounding by socioeconomic class and intelligence. Clinicians should look out for cognitive impairment in heavy drinkers, considering that abstinence may induce a degree of clinical improvement. Discussions with patients regarding moderate drinking should be informed by recent research. Health benefits of moderate drinking at least for cognitive function are questionable, and if they exist are probably limited to one unit of alcohol daily with respect to other body systems. IntroduCtIonAlcohol use is widespread and increasing across the developed world. Latest figures suggest that 58% of the UK population is drinking in excess of existing safe limits, 1 with 5% men and 4% of women consuming hazardous amounts (>50 units (400 g) for men and >35 units (280 g) for women weekly). Drinking in women and older adults of both sexes has been increasing, 2 with the percentage of those >65 years drinking increasing from 71% to 75% between 2005 and 2016. Those over 65 years of age are now more likely than any other age group to have drunk on at least 5 days in the preceding week.1 Alcohol-related harm is estimated to cost England around £21 billion per year, with £3.5 billion to the NHS, £11 billion tackling alcohol-related crime and £7.3 billion from lost work days and productivity costs. Health concerns associated with alcohol use have focused on liver dysfunction and more recently cancer. The public are largely ignorant of the potential risks of drinking with regards to cognition, in contrast to widespread knowledge of effects on the liver.3 Recommended drinking guidelines have remained unchanged in the UK from 1987 until 2016. Safe limits for men were set at 21 units (168 g) and for women at 14 units (112 g) per week pre-2016. Recent evidence of associations with cancer risk 4 at lower doses prompted revision of UK government alcohol guidance to 14 units (112 g) for both sexes, but current US guidelines still suggest that up to 24.5 units (196 g) weekly is safe for men.This clinical review summarises established effects of chronic heavy drinking on brain and behaviour/cognitive function, as well as the poorly understood impact of moderate consumption. Impl...

Alcohol use and burden for 195 countries and territories, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016

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Cognitive impairment in multiple sclerosis: An exploratory analysis of environmental and lifestyle risk factors

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Impact of Coffee, Wine, and Chocolate Consumption on Cognitive Outcome and MRI Parameters in Old Age

“…The relationship between drinking and cognitive performances in old age remains a highly controversial issue. The deleterious effect of heavy wine consumption on cognitive evolution over time in elderly controls has been already documented [ 8 , 9 , 10 , 64 , 65 ]. Several lines of evidence have suggested that moderate drinking could have a slight positive impact on memory and verbal abilities [ 66 , 67 ] but negative data have been also reported [ 64 , 68 ].…”

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