Smoking identified as key factor in accelerated cognitive decline

Smoking may be among the most important lifestyle factors affecting how quickly cognitive skills decline with age, suggests a new study led by UCL researchers, Report informs referring to News-Medical.net.

The study, published in Nature Communications, analyzed data from 32,000 adults aged 50 or over from 14 European countries who responded to surveys over 10 years.

The researchers investigated how rates of cognitive decline might differ among cognitively-healthy older adults with different combinations of health-related behaviors, including smoking, physical activity, alcohol consumption and social contact.

Cognitive function was assessed according to participants' performance in memory and verbal fluency tests.

Participants were grouped into lifestyles based on whether they smoked or not, whether they did both moderate and vigorous physical activity at least once per week, whether they saw friends and family at least weekly, and whether they drank more or the same/less than two alcoholic drinks per day (men) or one drink per day (women).

They found that cognitive decline was faster for lifestyles that included smoking, while cognitive decline was generally similar for all non-smoking lifestyles. Smoking lifestyles had cognitive scores that declined up to 85% more over 10 years than non-smoking lifestyles.

The exception was smokers who had a healthy lifestyle in all other areas – that is, they did regular exercise, drank alcohol in moderation, and socialized regularly. This group had a rate of cognitive decline similar to non-smokers.

The researchers accounted for a range of factors that might have influenced the findings, including age, gender, country, education, wealth, and chronic conditions.