title: Tobacco smoking behaviors in bipolar disorder: a comparison of the general population, schizophrenia, and major depression.
abstract: OBJECTIVE
  This study compared the prevalence of tobacco smoking behaviors in patients with bipolar disorder with normal and psychiatric (schizophrenia and major depression) controls. The main goal was to establish that bipolar patients smoke more than normal controls. Differences with psychiatric controls were explored.
  
  
  METHODS
  Samples of 424 patients (99 bipolar, 258 schizophrenia and 67 major depression) and 402 volunteer controls were collected in Central Kentucky. Smoking data for Kentucky's general population were available. Odds ratios (ORs) and their 95% confidence intervals (CIs) were used to establish the strength of associations. Logistic regression was used to adjust ORs for confounding variables.
  
  
  RESULTS
  Using epidemiological definitions of smoking behaviors and the general population as controls provided bipolar disorder unadjusted ORs of 5.0 (95% CI: 3.3-7.8) for current cigarette smoking, 2.6 (95% CI: 1.7-4.4) for ever cigarette smoking, and 0.13 (95% CI: 0.03-0.24) for smoking cessation. Using a clinical definition and volunteers as controls provided respective bipolar disorder adjusted ORs of 7.3 (95% CI: 4.3-12.4), 4.0 (95% CI: 2.4-6.7), and 0.15 (95% CI: 0.06-0.36). Prevalences of current daily smoking for patients with major depression, bipolar disorder, and schizophrenia were 57%, 66%, and 74%, respectively.
  
  
  CONCLUSIONS
  Bipolar disorder was associated with significantly higher prevalences of tobacco smoking behaviors compared with the general population or volunteer controls, independently of the definition used. It is possible that smoking behaviors in bipolar disorder may have intermediate prevalences between major depression and schizophrenia, but larger samples or a combination of multiple studies (meta-analysis) will be needed to establish whether this hypothesis is correct.
authors.affiliation: Department of Statistics, Universidad Nacional, Medellin, Colombia.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Diaz
authors.forename: Danielle
authors.initials: D
authors.lastname: James
authors.forename: Sheila
authors.initials: S
authors.lastname: Botts
authors.forename: Lorraine
authors.initials: L
authors.lastname: Maw
authors.forename: Margaret T
authors.initials: MT
authors.lastname: Susce
authors.forename: Jose
authors.initials: J
authors.lastname: de Leon
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000150:complications / Q000453:epidemiology* / Q000523:psychology; D016001:Confidence Intervals; D003865:Major Depressive Disorder / Q000150:complications / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D044382:Population Groups; D015995:Prevalence; D012559:Schizophrenia / Q000150:complications / Q000453:epidemiology*; D012565:Schizophrenic Psychology; D012907:Smoking / Q000453:epidemiology*