title: Neuroanatomical abnormalities that predate the onset of psychosis: a multicenter study.
abstract: BACKGROUND
  People experiencing possible prodromal symptoms of psychosis have a very high risk of developing the disorder, but it is not possible to predict, on the basis of their presenting clinical features, which individuals will subsequently become psychotic. Recent neuroimaging studies suggest that there are volumetric differences between individuals at ultra-high risk (UHR) for psychosis who later develop psychotic disorder and those who do not. However, the samples examined to date have been small, and the findings have been inconsistent.
  
  
  OBJECTIVE
  To assess brain structure in individuals at UHR for psychosis in a larger and more representative sample than in previous studies by combining magnetic resonance imaging data from 5 different scanning sites.
  
  
  METHODS
  Case-control study.
  
  
  METHODS
  Multisite.
  
  
  METHODS
  A total of 182 individuals at UHR and 167 healthy controls. Participants were observed clinically for a mean of 2 years. Forty-eight individuals (26.4%) in the UHR group developed psychosis and 134 did not.
  
  
  METHODS
  Magnetic resonance images were acquired from each participant. Group differences in gray matter volume were examined using optimized voxel-based morphometry.
  
  
  RESULTS
  The UHR group as a whole had less gray matter volume than did controls in the frontal regions bilaterally. The UHR subgroup who later developed psychosis had less gray matter volume in the left parahippocampal cortex than did the UHR subgroup who did not.
  
  
  CONCLUSIONS
  Individuals at high risk for psychosis show alterations in regional gray matter volume regardless of whether they subsequently develop the disorder. In the UHR population, reduced left parahippocampal volume was specifically associated with the later onset of psychosis. Alterations in this region may, thus, be crucial to the expression of illness. Identifying abnormalities that specifically predate the onset of psychosis informs the development of clinical investigations designed to predict which individuals at high risk will subsequently develop the disorder.
authors.affiliation: Department of Psychosis Studies, Institute of Psychiatry, King’s College London, London, United Kingdom.
authors.forename: Andrea
authors.initials: A
authors.lastname: Mechelli
authors.forename: Anita
authors.initials: A
authors.lastname: Riecher-Rössler
authors.forename: Eva M
authors.initials: EM
authors.lastname: Meisenzahl
authors.forename: Stefania
authors.initials: S
authors.lastname: Tognin
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Wood
authors.forename: Stefan J
authors.initials: SJ
authors.lastname: Borgwardt
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Koutsouleris
authors.forename: Alison R
authors.initials: AR
authors.lastname: Yung
authors.forename: James M
authors.initials: JM
authors.lastname: Stone
authors.forename: Lisa J
authors.initials: LJ
authors.lastname: Phillips
authors.forename: Patrick D
authors.initials: PD
authors.lastname: McGorry
authors.forename: Isabel
authors.initials: I
authors.lastname: Valli
authors.forename: Dennis
authors.initials: D
authors.lastname: Velakoulis
authors.forename: James
authors.initials: J
authors.lastname: Woolley
authors.forename: Christos
authors.initials: C
authors.lastname: Pantelis
authors.forename: Philip
authors.initials: P
authors.lastname: McGuire
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000473:pathology*; D016022:Case-Control Studies; D018450:Disease Progression; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D005500:Follow-Up Studies; D005625:Frontal Lobe / Q000473:pathology; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009929:Organ Size / Q000502:physiology; D020534:Parahippocampal Gyrus / Q000473:pathology; D011618:Psychotic Disorders / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology*; D012016:Reference Values; D018570:Risk Assessment; D012984:Software; D013702:Temporal Lobe / Q000473:pathology; D055815:Young Adult