Structural brain changes in psychotic adolescents
MedWire News: Adolescents who develop psychosis show significant structural brain changes around the time of illness onset, researchers report.
"These changes cannot be attributed to (antipsychotic) medication use and are therefore likely to reflect a pathophysiological process related to clinical manifestation of psychosis," say Tim Ziermans (Karolinska Institute, Stockholm, Sweden) and team.
The findings come from a study of 43 adolescents, aged 12-18 years at baseline, at ultra-high risk (UHR) for psychosis and 30 mentally healthy adolescents.
Magnetic resonance imaging was used to assess total brain, gray matter, white matter, cerebellum, and ventricle volume, as well as cortical thickness, at baseline and 2 years later.
There were no significant volumetric differences between groups at baseline, and no significant between-group differences over time regarding total brain, gray matter, lateral ventricle, and cerebellum volumes, the researchers note.
However, UHR patients showed a smaller increase in white matter volume than controls over the study period, at 0.35% versus 1.68%, and more cortical thinning in the left middle temporal gyrus.
UHR patients who developed psychosis (n=8) during follow-up showed a significantly greater decrease in total brain volume compared with UHR patients who did not develop psychosis (n=35) and controls (-1.28 vs -0.26 and -0.52%, respectively).
UHR patients who developed psychosis also showed a reduction in white matter volume over time compared with an increase in UHR patients who did not develop psychosis (-0.33 vs 0.64%).
In addition, UHR patients who developed psychosis had significantly more thinning than controls in widespread areas in the left anterior cingulate cortex, precuneus, and parts of the temporo-parieto-occipital area. No such differences were found between controls and UHR patients who did not develop psychosis.
Ziermans et al conclude in Schizophrenia Bulletin: "Our findings suggest that progressive brain changes are present at the time of, and related to, the development of psychosis.
"Future longitudinal studies are needed to compare the efficacy of early intervention strategies and address how these can prevent psychosis and associated brain changes from occurring."
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By Mark Cowen