Smoking and depression among psychiatric patients

The present study examined the relationship between smoking and depression among patients with different psychiatric diagnoses according to DSM-III-R criteria. The study sample of 1217 consecutive in- and outpatients, treated at the Department of Psychiatry, Kuopio University Hospital, in eastern Finland, was interviewed with two sets of questions during May 1993. The prevalence of smoking was higher among severely depressive than among mildly or moderately depressive patients in all diagnostic categories, except in male schizophrenics. However, this difference in rate of smoking was statistically significant only among men with major depression and women with personality disorder. The best determinants of severe depression in a multiple logistic model were diagnosis of major depression, personality disorder, and dysthymia. According to the model, current smokers had a 40% higher risk of severe depression than nonsmokers. Because both smoking and depression are major public health problems, the observed association deserves more thorough research, especially by psychiatric specialists.