A new study found that cognitive decline is less in individuals who quit smoking than in their smoking counterparts.
Because slower cognitive decline is associated with a lower risk of dementia, the study results add to the body of evidence suggesting that quitting smoking may protect against the disease.
The study was conducted by researchers from University College London, and the results of the study were published in The Lancet Healthy Longevity on October 13, and the Eurek Alert website wrote about it.
The study compared more than 4,700 participants who quit smoking with a similar number of people who continued smoking. The two groups were matched in terms of their initial cognitive scores and other factors, such as age, educational level, and country of birth.
The ages of the participants were 40 years and over (with an average age of 58 years), and data from individuals from 12 countries was used, including England, the United States, and a number of European countries.
The results of cognitive tests among people who quit smoking were compared to the results of a similar control group who continued smoking.
Convincing motive
“Our study suggests that quitting smoking may help people maintain better cognitive health over the long term, even into their 50s or beyond,” said study co-author Dr Michaela Blomberg from the Institute of Epidemiology and Healthcare at University College London.
She added: “We already know that quitting smoking, even in advanced stages of life, is often followed by an improvement in physical health, and it appears that, for our cognitive health as well, it is never too late to quit smoking.”
This finding is particularly important, because middle-aged and older smokers are less likely to try to quit smoking than younger groups.
Evidence that quitting smoking may support cognitive health may provide a compelling new motivation for this group to try to quit smoking.
Smoking harms brain health in part because it affects cardiovascular health, causing damage to the blood vessels that supply the brain with oxygen.
It affects cognitive health by causing chronic inflammation and directly damaging brain cells through oxidative stress, as a result of the formation of unstable molecules called free radicals.
The research team noted that their results are consistent with previous studies showing that adults over the age of 65 who quit smoking in early or middle age have cognitive scores similar to those who have never smoked, and that former smokers and non-smokers have a similar risk of developing dementia a decade or more after quitting smoking.