Cortical thickness and subcortical volumes in schizophrenia and bipolar disorder.
BACKGROUND
Schizophrenia and bipolar disorder are severe psychiatric diseases with overlapping symptomatology. Widespread brain morphologic abnormalities, including cortical thinning and subcortical volume reductions, have been demonstrated in schizophrenia but it is unclear whether similar abnormalities are present in bipolar disorder. The purpose of this study was to compare cortical thickness and subcortical volumes in schizophrenia and bipolar disorder, to assess differences and similarities in cortical and subcortical brain structure.


METHODS
We analyzed magnetic resonance images from a sample of 173 patients with schizophrenia spectrum disorder, 139 patients with bipolar disorder, and 207 healthy control subjects. Cortical thickness was compared between the groups in multiple locations across the continuous cortical surface. Subcortical volumes were compared on a structure-by-structure basis.


RESULTS
There was widespread cortical thinning in schizophrenia compared with control subjects, in frontal, temporal, occipital, and smaller parietal regions. There was no cortical thinning in bipolar disorder compared with control subjects or in schizophrenia compared with bipolar disorder. However, the subgroup of patients with bipolar disorder Type 1 showed cortical thinning, primarily in the frontal lobes and superior temporal and temporoparietal regions. Both patient groups showed substantial subcortical volume reductions bilaterally in the hippocampus, the left thalamus, the right nucleus accumbens, the left cerebellar cortex, and the brainstem, along with substantial ventricular enlargements.


CONCLUSIONS
We found substantial overlap in the underlying brain morphologic abnormalities in schizophrenia and bipolar disorder in subcortical structures, and between schizophrenia and bipolar disorder Type 1 in the cerebral cortex.
Rimol
Lars M
LM
Department of Psychiatry, Section Vinderen, University of Oslo, Oslo, Norway. lmr1999@hotmail.com
Hartberg
Cecilie B
CB
Nesvåg
Ragnar
R
Fennema-Notestine
Christine
C
Hagler
Donald J
DJ
Pung
Chris J
CJ
Jennings
Robin G
RG
Haukvik
Unn K
UK
Lange
Elisabeth
E
Nakstad
Per H
PH
Melle
Ingrid
I
Andreassen
Ole A
OA
Dale
Anders M
AM
Agartz
Ingrid
I
D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000188:drug therapy / Q000473:pathology*; D001921:Brain / Q000187:drug effects / Q000473:pathology*; D001931:Brain Mapping; D005260:Female; D005500:Follow-Up Studies; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000188:drug therapy / Q000473:pathology*
D000928:Antidepressive Agents; D014150:Antipsychotic Agents