Not only does smoking harm lung and heart health, but it increases the chances of middle-aged memory loss and confusion, a new study shows.
The likelihood of mental ("cognitive") decline is lower for those who quit — even if they did so only recently, according to researchers at Ohio State University, in Columbus.
Past research has established a connection between smoking and Alzheimer’s disease or other types of dementia.
This new study used a one-question self-assessment to ask participants if they were experiencing worsening or more frequent memory loss or confusion (also known as "subjective cognitive decline").
Using the 2019 Behavioral Risk Factor Surveillance System Survey, the researchers compared subjective cognitive decline measures for current smokers, recent former smokers and those who had quit years earlier, analyzing more than 136,000 people aged 45 and older. About 11% reported subjective cognitive decline.
“The association we saw was most significant in the 45 to 59 age group, suggesting that quitting at that stage of life may have a benefit for cognitive health,” said senior study author Jeffrey Wing, an assistant professor of epidemiology at Ohio State.
The researchers did not find a similar difference in the oldest group in the study, which could mean that quitting earlier is more beneficial, Wing suggested.
The prevalence of subjective cognitive decline in the study’s smokers was almost 1.9 times that of nonsmokers. For those who had quit less than 10 years ago, it was 1.5 times that of nonsmokers.
Quitting longer ago had more benefit. Those who quit more than a decade before the survey had a subjective cognitive decline prevalence just slightly above the nonsmoking group, the researchers found.
According to lead study author Jenna Rajczyk, a PhD student in Ohio State’s College of Public Health, “These findings could imply that the time since smoking cessation does matter, and may be linked to cognitive outcomes.”
Self-reported experiences aren’t a diagnosis and don’t independently confirm a person’s decline out of the normal aging process, Wing said. However, this could be a simple, low-cost tool to assess subjective cognitive decline.
“This is a simple assessment that could be easily done routinely, and at younger ages than we typically start to see cognitive declines that rise to the level of a diagnosis of Alzheimer’s disease or dementia,” Rajczyk said in a university news release. “It’s not an intensive battery of questions. It’s more a personal reflection of your cognitive status to determine if you’re feeling like you’re not as sharp as you once were.”
The findings were published recently in the Journal of Alzheimer’s Disease.
The U.S. Centers for Disease Control and Prevention has more on subjective cognitive decline.
SOURCE: Ohio State University, news release, Dec. 1, 2022