title: Regional gray matter volume abnormalities in the at risk mental state.
abstract: BACKGROUND
  Individuals with an At Risk Mental State (ARMS) have a very high risk of developing a psychotic disorder but the basis of this risk is unclear. We addressed this issue by studying gray matter volume in this group with magnetic resonance imaging (MRI).
  
  
  METHODS
  Thirty-five individuals with an ARMS, 25 patients with first episode schizophrenia, and 22 healthy volunteers were studied using a 1.5T MRI scanner. Twelve (34%) of the ARMS group developed schizophrenia in the 2 years subsequent to scanning.
  
  
  RESULTS
  There were significant volumetric differences between the three groups in the left insula, superior temporal gyrus, cingulate gyrus and precuneus. In these regions, the volume in the ARMS group was smaller than in volunteers but not significantly different from that in the first episode (FE) group. Direct comparison of the ARMS and control groups revealed additional areas of reduced volume in the left medial temporal cortex. Within the ARMS group, those subjects who later developed psychosis had less gray matter than subjects who did not in the right insula, inferior frontal and superior temporal gyrus.
  
  
  CONCLUSIONS
  The ARMS was associated with reductions in gray matter volume in areas that are also reduced in schizophrenia, suggesting that these are a correlate of an increased vulnerability to psychosis. Volumetric differences within the ARMS group may be related to the subsequent onset of schizophrenia in a subset of those at high risk.
authors.affiliation: Psychiatric Outpatient Department, University Hospital Basel, Switzerland. sborgwardt@uhbs.ch
authors.forename: Stefan J
authors.initials: SJ
authors.lastname: Borgwardt
authors.forename: Anita
authors.initials: A
authors.lastname: Riecher-Rössler
authors.forename: Paola
authors.initials: P
authors.lastname: Dazzan
authors.forename: Xavier
authors.initials: X
authors.lastname: Chitnis
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Aston
authors.forename: Margret
authors.initials: M
authors.lastname: Drewe
authors.forename: Ute
authors.initials: U
authors.lastname: Gschwandtner
authors.forename: Sven
authors.initials: S
authors.lastname: Haller
authors.forename: Marlon
authors.initials: M
authors.lastname: Pflüger
authors.forename: Evelyne
authors.initials: E
authors.lastname: Rechsteiner
authors.forename: Marcus
authors.initials: M
authors.lastname: D'Souza
authors.forename: Rolf-Dieter
authors.initials: RD
authors.lastname: Stieglitz
authors.forename: Ernst-Wilhelm
authors.initials: EW
authors.lastname: Radü
authors.forename: Philip K
authors.initials: PK
authors.lastname: McGuire
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000473:pathology*; D002540:Cerebral Cortex / Q000473:pathology; D004292:Dominance, Cerebral / Q000502:physiology; D042241:Early Diagnosis; D005260:Female; D005500:Follow-Up Studies; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006179:Gyrus Cinguli / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D011569:Psychiatric Status Rating Scales; D012016:Reference Values; D012306:Risk; D012559:Schizophrenia / Q000175:diagnosis / Q000235:genetics*; D012565:Schizophrenic Psychology; D012569:Schizotypal Personality Disorder / Q000175:diagnosis / Q000235:genetics*