title: Brain volume in first-episode schizophrenia: systematic review and meta-analysis of magnetic resonance imaging studies.
abstract: BACKGROUND
  Studies of people with schizophrenia assessed using magnetic resonance imaging (MRI) usually include patients with first-episode and chronic disease, yet brain abnormalities may be limited to those with chronic schizophrenia.
  
  
  OBJECTIVE
  To determine whether patients with a first episode of schizophrenia have characteristic brain abnormalities.
  
  
  METHODS
  Systematic review and meta-analysis of 66 papers comparing brain volume in patients with a first psychotic episode with volume in healthy controls.
  
  
  RESULTS
  A total of 52 cross-sectional studies included 1424 patients with a first psychotic episode; 16 longitudinal studies included 465 such patients. Meta-analysis suggests that whole brain and hippocampal volume are reduced (both P<0.0001) and that ventricular volume is increased (P<0.0001) in these patients relative to healthy controls.
  
  
  CONCLUSIONS
  Average volumetric changes are close to the limit of detection by MRI methods. It remains to be determined whether schizophrenia is a neurodegenerative process that begins at about the time of symptom onset, or whether it is better characterised as a neurodevelopmental process that produces abnormal brain volumes at an early age.
authors.affiliation: Department of Psychiatry, University of North Carolina at Chapel Hill, Campus Box 7160, Chapel Hill, North Carolina 27599-7160, USA. Grant_Steen@med.unc.edu
authors.forename: R Grant
authors.initials: RG
authors.lastname: Steen
authors.forename: Courtney
authors.initials: C
authors.lastname: Mull
authors.forename: Robert
authors.initials: R
authors.lastname: McClure
authors.forename: Robert M
authors.initials: RM
authors.lastname: Hamer
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Lieberman
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000473:pathology*; D002552:Cerebral Ventricles / Q000473:pathology; D005260:Female; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D012107:Research Design; D012559:Schizophrenia / Q000473:pathology*