title: Effects of tobacco smoking on neuropsychological function in schizophrenia in comparison to other psychiatric disorders and non-psychiatric controls.
abstract: OBJECTIVE
  Compared to the general population cigarette smoking prevalence is elevated in psychiatric disorders such as schizophrenia (SZ), bipolar disorder (BD), and major depressive disorder (MDD). These disorders are also associated with neurocognitive impairments. Cigarette smoking is associated with improved cognition in SZ. The effects of smoking on cognition in BD and MDD are less well studied.
  
  
  METHODS
  We used a cross-sectional design to study neuropsychological performance in these disorders as a function of smoking status. Subjects (N = 108) were SZ smokers (n = 32), SZ non-smokers (n = 15), BD smokers (n = 10), BD non-smokers (n = 6), MDD smokers (n = 6), MDD non-smokers (n = 10), control smokers (n = 12), and control non-smokers (n = 17). Participants completed a neuropsychological battery; smokers were non-deprived.
  
  
  RESULTS
  SZ subjects performed significantly worse than controls in select domains, while BD and MDD subjects did not differ from controls. Three verbal memory outcomes were improved in SZ smokers compared with non-smokers; smoking status did not alter performance in BD or MDD.
  
  
  CONCLUSIONS
  These data suggest that smoking is associated with neurocognitive improvements in SZ, but not BD or MDD. Our data may suggest specificity of cigarette-smoking modulation of neurocognitive deficits in SZ.
authors: Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.
authors: Dominique
authors: D
authors: Morisano
authors: Victoria C
authors: VC
authors: Wing
authors: Kristi A
authors: KA
authors: Sacco
authors: Tamara
authors: T
authors: Arenovich
authors: Tony P
authors: TP
authors: George
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001714:Bipolar Disorder / Q000150:complications / Q000523:psychology*; D016022:Case-Control Studies; D003865:Major Depressive Disorder / Q000150:complications / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000150:complications / Q000523:psychology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D012559:Schizophrenia / Q000150:complications; D012565:Schizophrenic Psychology; D012907:Smoking / Q000523:psychology*