Resumen:
Both schizophrenia and bipolar disorder have been associated with progressive changes in grey matter (GM) volume. However, the temporal trajectories of these changes are poorly understood. The aim of this study was to assess longitudinal changes in grey matter volume subsequent to the first episode of schizophrenia and of affective psychoses. Adolescent patients with a first episode psychosis (n=26) were scanned twice using magnetic resonance imaging, at first presentation and after a 3-year follow-up period. An age-matched group of healthy volunteers (n=17) was scanned at the same time points. Within-group and between-group changes in regional grey matter volume were examined using voxel-based morphometry. There were significant group by time interactions (p(FDRcorr)<0.05) in the frontal, temporal, parietal, cerebellar cortex, and in the thalamus, mainly reflecting longitudinal reductions in the controls but not in the patients. Subdivision of the patient group revealed that there were similar longitudinal reductions in patients with affective psychoses as in the controls but no volumetric changes in patients with schizophrenia. Psychosis with onset in adolescence or early adulthood may be associated with a delay or a loss of longitudinal reductions in regional grey matter volume that normally occur at this stage of development. These changes may be specific to schizophrenia.
