Older adults may be more affected by a couple of glasses of wine than their younger counterparts are -- yet they are less likely to be aware of it, a new study suggests.
The findings, published in the March issue of the Journal of Studies on Alcohol and Drugs
, suggest that older adults should be particularly careful about driving after social drinking.
"How many times have you asked someone, 'Are you OK to drive?'" said senior researcher Sara Jo Nixon, Ph.D., of the University of Florida Gainesville. The problem, according to Nixon, is that there is a "disassociation" between people's perceptions of their abilities after a few drinks and their actual capabilities.
And this may be particularly true of older adults, Nixon and her colleagues found.
For their study, the researchers recruited 42 adults between the ages of 50 and 74, and 26 adults ages 25 to 35. Participants were randomly assigned to drink either a moderate amount of alcohol or a nonalcoholic "placebo" beverage. Each person in the alcohol group was given enough to achieve the same blood alcohol level.
Next, all participants completed the so-called Trail Making Test, which requires takers to connect numbered and lettered dots, in order, as quickly as possibly. It gauges visual-motor coordination, planning and the ability to move from one thought to the next.
They took the test twice, 25 minutes and 75 minutes after drinking.
In general, the researchers found, older adults in the alcohol group performed more poorly on the first test than their younger counterparts did -- an age gap not seen in the placebo group. Yet, when asked how they subjectively felt, the older drinkers thought they were less impaired.
The extra effects of alcohol on seniors are subtle, Nixon pointed out, but could become important behind the wheel of a car.
Her advice to older social drinkers: "Sit around for a while and let the alcohol metabolize. Don't drink and run -- stay and have dessert."
It's not clear why the same blood level of alcohol would affect older and younger adults differently. But it does not seem to be a difference in alcohol metabolism, Nixon said. Instead, she explained, alcohol may affect the brain of older adults differently.
Nixon also pointed out that the study looked only at the immediate effects of alcohol and does not speak to the potential long-term effects of social drinking on brain function. Many studies have suggested that moderate drinking -- such as a glass of wine each day -- may have long-term health benefits, including a lower risk of heart disease.