Study finds smoking could be most important factor affecting cognition with age

According to a study, individuals who smoke might encounter a decline of up to 85% in their cognitive abilities, such as memory and speech, in comparison to non-smokers. Researchers examined 16 different lifestyle factors, such as physical activity, alcohol consumption, and social interactions, and discovered that smoking habits could have the greatest impact on the rate at which cognition diminishes with age.

"Our findings suggest that among the healthy behaviours we examined, not smoking may be among the most important in terms of maintaining cognitive function," Mikaela Bloomberg from University College London, UK, and lead author of the study published in the journal Nature Communications, said.

The researchers conducted a survey of more than 32,000 adults, all aged 50 or older, from 14 different European countries. They followed these individuals for up to 13 years. Based on their



answers, the participants were categorized according to their smoking behaviours and whether they engaged in moderate or vigorous physical activity at least once a week. The frequency of their social interactions with friends and family per week, as well as their alcohol consumption, were also examined.

According to the study, individuals who smoked and led a less social lifestyle experienced a significantly faster decline in cognitive skills over a 10-year period, with up to an 85% higher rate of decline compared to non-smokers. Moreover, smokers who preferred less social interactions appeared to be the most impacted, with a decline in cognition ranging from one-third to 50% over the same period.

"Our study is observational so cannot definitively establish cause and effect, but it suggests smoking might be a particularly important factor influencing the rate of cognitive ageing," Bloomberg said.