For Early-Stage Alzheimer's, a Little Alcohol May Be a Good Thing

New research suggests that people with early-stage Alzheimer's disease don't need to completely avoid alcohol. REUTERS/Michaela Rehle

It's well known that drinking alcohol impacts a person's neurological health and can impair brain function and behavior. For example, alcohol may trigger migraines and worsen symptoms of depression and anxiety. This is why new research that finds drinking modest amounts of alcohol could be beneficial to a person with early-stage Alzheimer's disease is so surprising.

The study, published Thursday in BMJ, suggests patients with dementia and Alzheimer's disease who drink lightly are less likely to die at an early stage of the illness. Overall, consuming two to three units of alcohol was linked to a 77 percent lower risk for death in early stages of dementia compared with those who drink one or less units each day. Two to three units of alcohol is equivalent to about a pint of beer, a glass of wine or a double gin and tonic. Additionally, the researchers found that drinking more than three units of alcohol had the same effect on mortality as drinking none, but sticking with two to three units made the difference.

The study involved 321 people who had a score of 20 or lower on a standard 30-question cognitive test known as the mini-mental state exam. All were part of the Danish Alzheimer Intervention Study. Around 71 percent drank one or fewer units of alcohol each day, and 17 percent drank two to three units.

The reasons are unclear, but the researchers present a number of theories. For example, studies find when healthy people consume moderate amounts of alcohol, it does provide some protective benefits, and this phenomenon may also apply to people with Alzheimer's. Another theory is that because drinking is often a social activity, people with Alzheimer's disease who drink a bit are also experiencing the benefits of human interaction, known to lower feelings of loneliness and depression—both of which have been linked to earlier death in aging individuals.

There may also be some physiological effects at play, the researchers suggest. Moderate drinking lowers the risk for cardiovascular disease, which is the leading cause of death. Other studies find that modest amounts of alcohol help modulate inflammation in the body by lowering interleukin 6, a type of protein produced by the body that helps regulate the immune system. Alcohol has also been found to increase insulin sensitivity, which allows a person to process carbohydrates efficiently.

Currently, most aging experts recommend patients diagnosed with Alzheimer's disease limit alcohol intake because some studies have found it can worsen neurocognitive symptoms. Alcohol has also been linked to memory problems. One study published in Neurology that involved 7,000 people found more than two and a half drinks each day could speed up memory loss by up to six years.

The authors of the new study say more research is needed to understand how moderate alcohol consumption might impact the health of a person with Alzheimer's disease, especially since their research does have some limitations. For example, it may be that those who didn't drink were more likely to be suffering from a terminal illness already and were abstaining because of that fatal disease. The data used in the study also were not based on research specifically designed to understand the alcohol-Alzheimer's disease connection, but rather is from a general intervention study for Alzheimer's patients. The sample size is also relatively small.

"We cannot solely on the basis of this study neither encourage nor advise against moderate alcohol consumption in patients with [Alzheimer's]," they write. "Further studies are needed on this area. Studies on the effect of alcohol on cognitive decline and disease progression in patients with mild [Alzheimer's]would be especially interesting."