Amygdala volume is reduced in early course schizophrenia

Psychiatry Res Neuroimaging. 2016 Apr 30:250:50-60. doi: 10.1016/j.pscychresns.2016.02.006. Epub 2016 Feb 12.

Abstract

Subcortical structural alterations have been implicated in the neuropathology of schizophrenia. Yet, the extent of anatomical alterations for subcortical structures across illness phases remains unknown. To assess this, magnetic resonance imaging (MRI) was used to examine volume differences of major subcortical structures: thalamus, nucleus accumbens, caudate, putamen, globus pallidus, amygdala and hippocampus. These differences were examined across four groups: (i) healthy comparison subjects (HCS, n=96); (ii) individuals at high risk (HR, n=21) for schizophrenia; (iii) early-course schizophrenia patients (EC-SCZ, n=28); and (iv) chronic schizophrenia patients (C-SCZ, n=20). Raw gray matter volumes and volumetric ratios (volume of specific structure/total gray matter volume) were extracted using automated segmentation tools. EC-SCZ group exhibited smaller bilateral amygdala volumetric ratios, compared to HCS and HR subjects. Findings did not change when corrected for age, level of education and medication use. Amygdala raw volumes did not differ among groups once adjusted for multiple comparisons, but the smaller amygdala volumetric ratio in EC-SCZ survived Bonferroni correction. Other structures were not different across the groups following Bonferroni correction. Smaller amygdala volumes during early illness course may reflect pathophysiologic changes specific to illness development, including disrupted salience processing and acute stress responses.

Keywords: Chronic; Illness stage; Neuroimaging; Structural.

MeSH terms

  • Adolescent
  • Adult
  • Amygdala / diagnostic imaging*
  • Amygdala / pathology
  • Early Diagnosis
  • Female
  • Globus Pallidus / diagnostic imaging
  • Globus Pallidus / pathology
  • Gray Matter / diagnostic imaging
  • Gray Matter / pathology
  • Hippocampus / diagnostic imaging
  • Hippocampus / pathology
  • Humans
  • Magnetic Resonance Imaging* / methods
  • Male
  • Nucleus Accumbens / diagnostic imaging
  • Nucleus Accumbens / pathology
  • Organ Size
  • Putamen / diagnostic imaging
  • Putamen / pathology
  • Schizophrenia / diagnostic imaging*
  • Schizophrenia / drug therapy
  • Schizophrenia / pathology
  • Thalamus / diagnostic imaging
  • Thalamus / pathology
  • Young Adult