Anhedonia in the deficit syndrome of schizophrenia

Previous studies have shown that anhedonia characterizes the deficit syndrome of schizophrenia. Anhedonia is also one of the main symptoms of the depressive state. The purpose of this study was to examine the relationships between anhedonia and depression in the deficit syndrome of schizophrenia. Self-evaluations of anhedonia and depression were performed by three groups of subjects (32 deficit schizophrenics, 32 major depressives, 35 healthy subjects) matched for sociodemographic variables. Deficit schizophrenics and major depressives are more anhedonic than controls, but there is no difference between the two study groups. Contrarily to what is evidenced for major depressives and for healthy subjects, the depressive symptomatology correlates with anhedonia in deficit schizophrenics. When deficit schizophrenics are dichotomized into depressed versus non-depressed patients, no difference is observed concerning anhedonia. These results suggest that anhedonia in the deficit syndrome of schizophrenia has no specificity but appears independent of coexisting depression and covaries with several characteristics of depression (retardation, cognitive distortions). Our results support the hypothesis that the deficit syndrome of schizophrenia could constitute a non-depressive mood disorder.