Heavy Drinking Hastens Cognitive Decline in Men

Men who are heavy drinkers show a faster cognitive decline compared with men who consume light to moderate amounts of alcohol, according to a new study. The middle-age men who averaged 3 or more drinks per day showed faster 10-year declines in cognitive function than did lighter drinkers.

“The detrimental effect of heavy alcohol consumption on health is well documented. This study adds a new argument against heavy drinking, showing that it is also detrimental for cognitive aging, with effects evident as early as age 55 years,” lead author Séverine Sabia, PhD, from the Department of Epidemiology & Public Health at University College London, told ConsultantLive.

“For example, heavy drinking men aged 60 years old show a decline in memory comparable to men aged 66 years old,” she noted.

Dr Sabia and colleagues analyzed data from more than 7000 British civil servants, average age 56 years, who had agreed to complete lifestyle questionnaires and to undergo a physical examination beginning in the 1980s. About two-thirds of the participants were men. Alcohol consumption was assessed 3 times in the 10 years preceding the first cognitive assessment in the late 1990s. Cognitive tests were repeated twice more in the 2000s. The cognitive test battery included 4 tests that assessed memory and executive function.

The participants were stratified into 6 groups according to drinking status, including complete abstainers; those who stopped drinking entirely at some point during follow-up; “occasional” drinkers (their average daily alcohol consumption was not quantified); and light, moderate, and heavy regular drinkers.

Almost two-thirds of the men were light drinkers, just under 20% were moderate drinkers, and just under 10% were heavy drinkers. The researchers used the light drinkers as the reference group to analyze drinking and cognitive decline.

Compared with the declines observed in the light drinkers, declines in cognitive scores were statistically higher in the heavy-drinking men but did not differ for the other groups. The scores on 4 tests of short-term memory and executive function dropped the most in the heaviest male drinkers.

“Although we cannot completely exclude confusing effects from an unhealthy lifestyle, we did take into account fruit and vegetable consumption, physical activity, and smoking in the analyses,” said Dr Sabia. “The mechanisms underlying the association between alcohol consumption and cognition are complex. The main hypothesis focuses on cerebrovascular and cardiovascular pathways, involving effects that play out over an extended period of time. Heavy alcohol consumption is associated with higher risk of vascular disease which, in turn, may increase the risk of cognitive impairment.”

In addition, Dr Sabia noted that “heavy alcohol consumption has detrimental short-term and long-term effects on the brain, including direct neurotoxic effects, pro-inflammatory effects, and indirect impact via cerebrovascular disease and vitamin deficiency.”

Dr Sabia’s message to primary care physicians is “to advise patients to reduce alcohol consumption. Our findings are in agreement with previous studies showing that moderate alcohol consumption is probably not deleterious for cognitive outcomes, but they also show that heavy alcohol consumption in midlife is likely to be harmful for cognitive aging, at least in men.”

The researchers published their results online on January 15, 2014 in the journal Neurology.