title: Psychosis effect on hippocampal reduction in schizophrenia.
abstract: BACKGROUND
  In schizophrenia, disruption of the neurodevelopmental processes may lead to brain changes and subsequent clinical manifestations of the illness. Reports of the progressive nature of these morphological brain changes raise questions about their causes. The possible toxic effects of repeated stressful psychotic episodes may contribute to the disease progression.
  
  
  OBJECTIVE
  To analyze the influence of illness duration and previous psychotic episodes on hippocampal gray matter volume (GMV) in schizophrenia.
  
  
  METHODS
  We performed an analysis of hippocampal GMV correlations with illness duration, number of previous psychotic episodes, and age in 24 schizophrenia patients and 24 matched healthy controls.
  
  
  RESULTS
  We found a cluster of GMV voxels in the left hippocampal tail that negatively correlated with the number of previous psychotic episodes, independent from the effect of age. On the other hand we found no effect of illness duration independent of age on the hippocampal GMV. Finally, we found a cluster of significant group-by-age interaction in the left hippocampal head.
  
  
  CONCLUSIONS
  We found an additive adverse effect of psychotic episodes on hippocampal morphology in schizophrenia. Our findings support toxicity of psychosis concept, together with etiological heterogeneity of brain changes in schizophrenia.
authors.affiliation: Department of Psychiatry, University Hospital Brno and Faculty of Medicine, Masaryk University, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Hýža
authors.forename: Jitka
authors.initials: J
authors.lastname: Huttlová
authors.forename: Miloš
authors.initials: M
authors.lastname: Keřkovský
authors.forename: Tomáš
authors.initials: T
authors.lastname: Kašpárek
mesh_terms: D000328:Adult; D000367:Age Factors; D016022:Case-Control Studies; D005260:Female; D007839:Functional Laterality; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000209:etiology* / Q000473:pathology*; D012559:Schizophrenia / Q000150:complications*; D055815:Young Adult
keywords: AAL; AMPA; BDNF; CA; DG; FDR; FWE; GABA; GLM; GMV; HPA; Hippocampus; MARTA; MRI; Morphometry; N-methyl D-aspartate; NMDA; Psychosis; SD; SDA; SPM; Schizophrenia; Toxicity; VBM; VGLUT1; WFU; Wake-Forrest University; automatic anatomical labeling; brain-derived neurotrophic factor; cornu ammonis; dentate gyrus; false discovery rate; family-wise errors; gamma-amino butyric acid; general linear model; gray matter volume; hypothalamo-pituitary axis; magnetic resonance imaging; multi-acting receptor-targeted antipsychotics; serotonine-dopamine antagonists; standard deviation; statistical parametrical mapping; vesicular glutamate transporter 1; voxel-based morphometry; α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid