Smoking and suicide among nurses.

Current evidence suggests a strong positive correlation between cigarette consumption and depression; this study examined the relationship between cigarettes and suicide. Over 100,000 predominantly White, middle-aged, female registered nurses were followed via biannual questionnaires from 1976 through 1988. Respondents smoking 1 through 24 cigarettes per day had twice the risk and those smoking 25 or more cigarettes four times the risk of committing suicide, compared with those who had never smoked. Although no information on causation was available, this paper links cigarettes to another major health problem.