Health Market Science

Researchers from University College in London recently discovered men who smoke experience a more rapid decline in brain function as they age, compared to their nonsmoking counterparts. Some male smokers report cognitive decline equal to men 10 years older than them who avoid tobacco products.

The researchers came to this conclusion after conducting a long-term study that showed smoking is linked to swifter cognitive decline in men, but no correlation was seen in women. Early dementia-like difficulties were seen in male smokers as young as 45 years old. It is already understood that smoking causes lung cancer and other chronic respiratory diseases and cardiovascular conditions, and the World Health Organization considers it one of the biggest threats to public health. But the study is one of the first bodies of study to link the habit to cognitive decline.

In an interview with Reuters, Severine Sabia who led the study, said one explanation for the gender difference in the effects smoking has on cognition is that men tend to smoke larger amounts of tobacco compared to women. The research team looked at the smoking history and cognitive health of 5,099 men and 2,137 women. The average age of the participant was 56 when they received their first cognitive assessment. Over the next 25, years, the participants received six other assessments of smoking status, and three cognitive assessments over 10 years. The study found smokers showed a cognitive decline as fast as nonsmokers 10 years older than them.

Sabia told the source men who quit smoking in the 10 years before the first cognitive testing point still had a heightened risk of rapid cognitive decline, particularly in executive function, the processes involved in achieving a specific goal. Long-term ex-smokers did not show a faster decline in their brain functions or cognitive abilities.

According to the study, several factors could account for the cognitive decline in smokers. Smoking affects the heart, lungs and blood vessels, which could harm the body's ability to deliver blood, oxygen and nutrients to the brain to help it function.

In an interview with ABC News, Dr. Charles DeCarli, director of the Alzheimer's Disease Center at the University of California at Davis, said differences in cardiovascular disease could explain why male smokers showed decline and female smokers did not.

"Men have more heart disease and greater stroke risk than women do up until about age 70 or so. Part of that is related to lifestyle," DeCarli said. "Men of this age group often smoked more than women did."