A study of physical anhedonia as a trait marker in schizophrenia

Inability to define the heritable phenotype might be a reason for failure to replicate results in psychiatric genetics. Hence, the use of a candidate symptom approach to identify more homogeneous forms of diseases among affected individuals and subclinical traits among first-degree relatives (FDRs) may increase genetic validity. The objective of the present study was to determine whether physical anhedonia can be used as a marker for individuals at risk of schizophrenia.

Physical anhedonia scores (measured using Revised Physical Anhedonia Scale [rPAS]) were compared across thirty remitted schizophrenic patients, thirty of their unaffected FDRs, and thirty healthy controls. We compared anhedonia scores among the three main groups using one-way ANOVA.

Physical anhedonia (rPAS) scores of the schizophrenic patient group were significantly higher than that of their FDRs and controls both, and physical anhedonia (rPAS) scores of FDRs were significantly higher than that of healthy controls (F = 115.33, P < 0.001). The subgroups did not differ on various other clinical characteristics.

Our data suggest that physical anhedonia is a candidate symptom for schizophrenia.