This may be a stretch. It may be more likely that people smoke because they have other stressors. Anyhow, I saw this a few weeks ago and thought it was interesting.
http://www.news-medical.net/?id=8236Association between cigarette smoking and suicidal thoughts and attempts
Medical Study News
Published: Monday, 7-Mar-2005
Suicidal thoughts or attempts are associated with daily smoking in current smokers, but not former smokers, according to an article in Archives of General Psychiatry.
"A link between cigarette smoking and suicide has been reported in epidemiological investigations since the 1970s," according to background information in the article. However, these interpretations have been subject to controversy. It is believed that depression may result in part from smoking and should not be controlled in analysis of this relationship. However, it's also been reported that symptoms of depression in adolescents predicts their starting smoking and that major depression leads to an increased risk for regular smoking and dependence; therefore, a history of depression must be considered when examining suicide in smokers.
Naomi Breslau, Ph.D., from Michigan State University, East Lansing, and colleagues examined the association between cigarette smoking and suicidal thoughts and attempts. Participants aged 21 to 30 years were interviewed in 1989 and completed follow-up interviews in 1992, 1994, and 1999 - 2001. At each assessment, they were asked about lifetime smoking history, whether they were current daily smokers or had been in the past, and psychiatric disorders. Nearly nine hundred people completed all three investigations.
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