Does Alcohol Cause Cognitive Impairment?
Alcohol has numerous detrimental effects on health, but according to a study from The University of Western Australia, it may not cause cognitive problems later in life, at least for older men. The paper, published in the journal Neurology, found that alcohol is not a direct cause of memory problems or cognitive impairment later in life.
“Heavy alcohol consumption is known to be detrimental to health, so these results were counter intuitive,” Professor Osvaldo Almeida, research director at The University of Western Australia’s Centre for Health and Ageing, said.
The researchers say it was a widely held belief, supported by previous association studies, that excessive consumption of alcohol is a cause of cognitive impairment, but the link had never been actually proven.
In an attempt to prove the link, Almeida and colleagues examined a gene known to be responsible for how successfully a person is able to metabolize alcohol. Essentially, they were looking at the gene establishing a person’s tolerance level for alcohol.
Using a study design called Mendelian randomization, the team analyzed the genetic data from 3,542 men between the ages of 65 and 83 years old. According to Medical Xpress, Mendelian randomization incorporates genetic information into more traditional epidemiological techniques.
Study participants were surveyed about their alcohol consumption over the past year, then they were classified as abstainers, occasional drinkers, and regular drinkers based on the number of standard drinks consumed per week. Drinking more than 35 standard drinks per week classified as alcohol abuse.
The researchers measured ‘cognitive impairment’ with a validated scale six years later. Cognitive impairment is defined for the sake of the study as a decrease in the brain’s processing sped and efficiency, as well as a deterioration in memory.
Professor Almeida said that if heavy alcohol consumption is to be considered a direct cause of cognitive impairment, then people with the genetic variant that makes them avoid alcohol should show a lower risk for cognitive impairment. However, that turned out to not be true.
The study found that alcohol consumption, including heavy regular drinking and abuse, was not a direct cause of cognitive impairment. Instead, it indirectly contributes to other causes such as poor nutrition and head injury.
The findings actually went as far as to say, “Our results are consistent with the possibility, but do not prove, that regular moderate drinking decreases the risk of cognitive impairment in older men.”