Early cerebral grey matter excess in basal ganglia after early treatment in first-onset, never-medicated schizophrenia

Abstract

Introduction: In the early weeks following neuroleptic treatment, patients never previously been exposed to antipsychotic medication and presenting with first-episode of schizophrenia may already demonstrate brain volumetric differences. Method: We used a comprehensive computational morphometry analysis of the brain. 38 individuals with first-episode psychosis were balanced for age, sex, handedness, ethnicity, height, education in years, paternal socio-economic status and PANSS score. They were a consecutive series presenting to their local hospital for treatment. BAMM (Brain activation and morphological mapping) software was used to measure grey matter, white matter and CSF volumes. 12 were treated with neuroleptics (NT) and 26 were neuroleptic-naìve (NN). The NT group had been scanned in the earlier stage of the project as a pilot group and did not differ in MRI scanning parameters. Groups did not differ in age, sex, socioeconomic class, handedness, ethnicity. In the NT group, significant clusters of volume excess in grey matter was detected bilaterally in the caudate, putamen, cingulate, cerebellum, and brainstem after around 18 days of neuroleptic treatment. Region-of-interest measurement of the caudate using T1 scans, 1.2mm, contiguous, 128 slices was done by a single operator blind to group membership. Results: It showed caudate volume significantly larger by 16% (on the left, p 0.012, 2 tailed) and 13% (on the right, p 0.028, 2 tailed) in the NT group. Conclusion: This is the first study to demonstrate that basal ganglia and extrastriatal grey matter excess is likely to occur early on within three weeks of initiating neuroleptic treatment.