Neural markers of remission in first-episode schizophrenia: a volumetric neuroimaging study of the hippocampus and amygdala.

OBJECTIVE: The temporolimbic region has been implicated in the pathophysiology in schizophrenia. More specifically, significantly smaller hippocampal volumes but not amygdala volumes have been identified at onset in first-episode schizophrenia (FES) patients. However, volumetric differences (namely, in the hippocampus) exhibit an ambiguous relationship with long-term outcome. So, we examined the relationship between hippocampus and amygdala volumes and early remission status. METHODS: We compared hippocampus and amygdala volumes between 40 non-remitted and 17 remitted FES patients and 57 healthy controls. Amygdala and hippocampus were manually traced with the hippocampus additionally segmented into three parts: body, head, and tail. Remission was defined as mild or less on both positive and negative symptoms over a period of 6 consecutive months as per the 2005 Remission in Schizophrenia Working Group criteria. RESULTS: A significant [group x structure x side] interaction revealed outcome groups differed in hippocampus tail volumes; significantly on the left (non-remitted=694+/-175 mm(3); remitted=855+/-133 mm(3); p=0.001) with a trend difference on the right (non-remitted=723+/-162 mm(3); remitted=833+/-126 mm(3); p=0.023). Groups did not differ in body, head, or amygdala volumes bi-laterally. CONCLUSIONS: A smaller hippocampal tail volume may represent a neural marker in FES patients who do not achieve early remission after the first 6 months of treatment. The early identification of patients with poor outcome with respect to the hippocampus tail may encourage the search for new, more target-specific, medications in hope of improving outcome and moving us towards a better understanding of the pathophysiology of schizophrenia.

Validation of the English and French versions of the Community Assessment of Psychic Experiences (CAPE) with a Montreal community sample.

OBJECTIVE: The aim of this study was to examine the reliability, validity and factor structure of the Community Assessment of Psychic Experiences (CAPE), a 42-item self-report questionnaire. We analyzed the internal consistency of the CAPE to determine whether the 3-factor structure (positive, negative and depressive symptoms) found by the CAPE authors would also be found in our sample. METHOD: A sample of 2275 individuals from the general community in the Montreal area completed the questionnaire in either French or English. RESULTS: The internal consistencies of the original three subscales were good and the confirmatory factor models had a good fit. The exploratory factor analysis suggested a 3-5-factor solution, without improving the alternative factor structures. The 4-factor solution separated positive symptoms into factors we called 'bizarre positive symptoms' and 'social delusions', and the 5-factor solution separated positive symptoms further and included a 'popular psychic beliefs' factor. Results suggest that the scalability might be improved by shortening the original questionnaire to 23 items with the same 3 original scales. CONCLUSION: We support the internal consistency of the CAPE. Although alternative scaling (4 and 5 factors) did not improve the model fit, researchers interested in distinguishing 3 factors of positive symptoms could find utility in these two new scales. Finally, reducing the number of CAPE items could be useful for shorter surveys. Future studies should test the implications of these suggestions.