People who are exposed to second-hand smoke are more likely to have psychological problems, compared with people who are not exposed to second-hand smoke.

These findings are from a study that looked at 5,560 non-smokers and 2,595 smokers. None of the subjects had a family history of mental illness. The non-smokers underwent saliva testing for exposure to second-hand smoke. Overall, 14.5% of study participants complained of psychological distress. Compared with non-smokers, smokers had a 2.45-fold increased risk of mental problems. And, a direct correlation was evident between exposure to second-hand smoke and risk of psychological distress. Specifically, non-smokers who were exposed to the highest levels of second-hand smoke were 62% more likely to suffer from psychological problems.

Over six-years of follow-up, smokers were 3.7 times more likely to be admitted to a psychiatric hospital, compared with people not exposed to smoke. Second-hand smokers were 2.8 times more likely to be admitted to a psychiatric hospital, compared with people who were not exposed to second-hand smoke.

Archives of General Psychiatry – June 2010;67(8).
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