[Anhedonia in schizophrenia]

Abstract

A study on 61 subjects who meet Spitzer's Research Diagnosis Criteria of schizophrenia and on 56 normal subjects has been conducted to explore anhedonia. Anhedonia was evaluated by two rating scales, the Physical Anhedonia Scale (PAS) and a sub-scale of physical pleasure (FCPCS-PP) extracted from the pleasure scale of Fawcett. The reliabilities of the scales were studied in the schizophrenic group by the Cronbach alpha and the Kuder Richardson (KR 20) coefficient and by the correlation between the two scales (concurrent validity). The Cronbach alpha was 0.77 for the FCPCS-PP and the KR 20 was 0.82 for the PAS. The correlation between the two scales was -0.37 (p < 0.01). The schizophrenics were significantly more anhedonic than normals with higher score on the PAS and with a lower score on the FCPCS-PP. Using the Beck Depression Inventory to rate depression in the schizophrenic group and to dichotomize these subjects into depressed schizophrenics and no depressed schizophrenics, we failed to find significantly differences concerning anhedonia scales between these two sub-groups of schizophrenics. There was no difference between in and outpatients concerning the anhedonia scales. Our results suggest that anhedonia would be a possible marker of schizophrenic disease. The distribution of the anhedonia scales in the schizophrenic group is normal or unimodal and it doesn't support the hypothesis of a qualitative sub-group of schizophrenics characterised by severe anhedonia.