title: Relationship between smoking and family history of smoking in schizophrenia patients.
abstract: BACKGROUND
  The rate of smoking is known to be high in patients with schizophrenia. The purpose of this study was to quantitatively examine the relationship between smoking and family history of smoking in patients with schizophrenia.
  
  
  METHODS
  The sample consisted of 172 patients (mean age: 54 years, 55% male) hospitalized in a general psychiatric hospital. They were asked by a physician whether they smoked. Family histories of smoking and schizophrenia were assessed among first- and third-degree relatives.
  
  
  RESULTS
  Ninety-eight patients (57%) were identified as having smoked at some point. Multiple logistic regression analysis showed that smoking was significantly associated with family histories of smoking among both first- and third-degree relatives, controlling for the effects of age, sex, and family history of schizophrenia. The smoking rates were significantly higher in those with a family history of smoking, but not a family history of schizophrenia, than among those without a family history of either smoking or schizophrenia. However, this difference did not reach statistical significance among those with a family history of schizophrenia.
  
  
  CONCLUSIONS
  Smoking is greatly influenced by family history of smoking in patients with schizophrenia, especially among those without a family history of schizophrenia. The association between smoking and family history of smoking was inconclusive among those patients with schizophrenia who also had a family history of schizophrenia.
authors.affiliation: Teikyo University School of Medicine, Kichijyoji Hospital, Japan. yshinozaki@partners.org
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Shinozaki
authors.forename: Mutsuhiro
authors.initials: M
authors.lastname: Nakao
authors.forename: Takeaki
authors.initials: T
authors.lastname: Takeuchi
authors.forename: Eiji
authors.initials: E
authors.lastname: Yano
mesh_terms: D015897:Comorbidity; D005190:Family / Q000523:psychology*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012559:Schizophrenia / Q000453:epidemiology*; D012565:Schizophrenic Psychology; D012907:Smoking / Q000453:epidemiology* / Q000523:psychology*