title: Seasons and depression: the influence of cigarette smoking.
abstract: The seasonality of depressive illness has been documented since antiquity. A review of 611 patients, who were consecutively admitted to the adult inpatient psychiatric unit of a mid-Michigan general hospital, examined the influence of cigarette smoking and psychiatric diagnosis upon the seasonal variation of admissions. Among the smokers, admissions for depressive disorders (n = 151) peaked in the springtime (z = 2.1, p < .05) and declined in summer. Admissions for the nonsmokers failed to demonstrate a substantial seasonal rhythm. Admissions for smokers and nonsmokers in other diagnostic groups did not show any seasonal variation. These findings parallel numerous studies regarding the influence of seasons upon rates of hospitalization for depressive disorder, and completed suicide. Therapeutic implications related to the bidirectional relationship between cigarette smoking and depression are discussed.
authors.affiliation: Department of Psychiatry, Michigan State University, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: D'Mello
authors.forename: C
authors.initials: C
authors.lastname: Flanagan
mesh_terms: D000328:Adult; D003863:Depression / Q000150:complications / Q000453:epidemiology*; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000150:complications / Q000453:epidemiology; D008824:Michigan / Q000453:epidemiology; D010507:Periodicity; D012189:Retrospective Studies; D012307:Risk Factors; D012621:Seasons; D012907:Smoking / Q000453:epidemiology*