Alcohol's Effects: Old vs. Young People

March 6, 2009 -- Social drinking seems to impair older people more than their younger drinking buddies. Also, older people are less likely to realize how the alcohol is affecting them, according to a new study.

The study, published in The Journal of Studies on Alcohol and Drugs, is based on a research study with 42 older participants between the ages of 50 and 74 and 26 younger participants between the ages of 25 and 35. All participants were social drinkers and nonsmokers.

For the study, some participants from each age group consumed a moderate amount of alcohol while others drank non-alcoholic placebo beverages. Participants took a test at 25 minutes and 75 minutes after drinking. The tests required them to connect letters and numbers in order with a line. It was designed to measure visual-motor coordination, planning, and the ability to move from one task to the next.

Participants also rated how intoxicated they felt and how much they thought the alcohol impaired their performance on the tests.

Although peak breath-alcohol measures were similar between the older and younger groups of drinkers, older participants who had received alcohol took longer to complete the test than the younger participants did. This performance age gap did not happen with non-drinkers. A difference wasn't seen between the older participants and younger participants who had consumed non-alcoholic beverages.

"That doesn't sound like much, but five seconds is a big difference if you're in a car and need to apply the brakes," researcher Sara Jo Nixon, a psychiatry professor at the University of Florida's McKnight Brain Institute, says in a news release. "It can mean the difference between a wreck, and not-a-wreck."

Also, older drinkers were less likely to realize they were impaired at the testing 25 minutes after alcohol consumption. That can be dangerous, as older drinkers may think they are fine to drive when they are not. At 75 minutes after alcohol consumption, the older drinkers reported more impairment although their test performance was similar to the older participants who hadn't consumed any alcohol.

Nixon offers this advice: "If you have a couple of drinks at dinner, sit around, have dessert -- don't drive for a while."

Alcohol consumption among older adults is likely to become a larger public health issue. More than half of adults over the age of 55 drink in social settings, according to background information in the study. Also, the percentage of the population that is older is projected to increase dramatically over the next couple of decades. By 2030, one in five U.S. residents will be over the age of 65.