CogniFit's Science blog: Second-Hand Smoke Causes More Damage Than You Thought

Second-Hand Smoke Causes More Damage Than You Thought

People who are exposed to second-hand smoke may have a greater risk of developing cognitive impairment.

Although they were unable to show a casual effect, researchers at Cambridge University found that cognitive impairment was more common among nonsmokers and former smokers, who had high levels of cotinine, a nicotine-related chemical, in their saliva samples.

The study included 4,809 adults, age 50 and older, in England. Between 1998 and 2002, they provided saliva samples and took various tests of mental skills, including memory and attention. Participants were considered cognitively impaired if their overall test score was in the bottom 10% of the group.

Non-smokers with the highest salivary levels of cotinine were 70% more likely to be cognitively impaired than non-smokers who had the lowest salivary levels of cotinine. Former smokers with the highest salivary cotinine levels were 32% more likely to have cognitive impairment than former smokers who had the lowest salivary cotinine levels.

More research is needed in order to determine if exposure to smoking definitely causes cognitive impairment, but this study certainly raises the strong possibility that it does.