title: Is there an association between cortical thickness, age of onset, and duration of illness in schizophrenia?
abstract: OBJECTIVE
  Several studies have shown cortical volume loss in frontotemporal regions in schizophrenia patients, and it is known that these reductions may be associated with disease symptoms and cognitive deficits. The aim of this study was to investigate possible cortical thickness correlations in frontotemporal regions in relation to age at onset and duration of illness.
  
  
  METHODS
  One hundred forty-eight schizophrenia patients (97 males; age and SD 36.30 ± 10.06) and 87 (57 males; age and SD 36.48 ± 10.10) age-matched healthy subjects underwent a brain MRI scan. Cortical segmentation and surface statistical analysis were performed using the FreeSurfer software package. Results were corrected for multiple comparisons using the Monte Carlo method considering a cluster-corrected Type I Error of 5%.
  
  
  RESULTS
  Compared to controls, schizophrenia patients presented significant cortical thinning in the frontotemporal, parietal, and occipital cortices. No correlation between prefrontal cortex thickness and duration of illness in patients with schizophrenia or between frontotemporal cortical thickness and age at onset was found. However, a significant interaction between age and diagnosis was observed on frontal cortical thickness with patients presenting a thinner cortex than expected for age.
  
  
  CONCLUSIONS
  Although there was no correlation between age of onset and duration of illness with brain volume, our findings suggest that there is an accelerated cortical loss in schizophrenia, thus reinforcing the progressive processes of the disease.
authors.affiliation: 1 Laboratório Interdisciplinar de Neurociências Clínicas (LiNC), Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil.
authors.forename: Idaiane Batista
authors.initials: IB
authors.lastname: Assunção Leme
authors.forename: Ary
authors.initials: A
authors.lastname: Gadelha
authors.forename: João Ricardo
authors.initials: JR
authors.lastname: Sato
authors.forename: Vanessa Kiyomi
authors.initials: VK
authors.lastname: Ota
authors.forename: Jair de Jesus
authors.initials: JJ
authors.lastname: Mari
authors.forename: Maria Isabel
authors.initials: MI
authors.lastname: Melaragno
authors.forename: Marilia de Arruda Cardoso
authors.initials: MA
authors.lastname: Smith
authors.forename: Sintia Iole Nogueira
authors.initials: SI
authors.lastname: Belangero
authors.forename: Rodrigo Affonseca
authors.initials: RA
authors.lastname: Bressan
authors.forename: Andrea Parolin
authors.initials: AP
authors.lastname: Jackowski
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000473:pathology*; D003072:Cognition Disorders / Q000209:etiology; D018450:Disease Progression; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000150:complications / Q000473:pathology*; D055815:Young Adult