Basic symptoms and psychotic symptoms: their relationships in the at risk mental states, first episode and multi-episode schizophrenia

In the field of the early psychosis two main approaches attempt to develop rating tools, one investigating the basic symptoms domain, and the other the attenuated psychotic symptoms. To explore the relationship between basic symptoms (BSs) and other symptom domains in different phases of the psychotic illness 32 at ultra-high risk (UHR), 49 first episode schizophrenia (FES), 42 multiple episode schizophrenia (MES), and 28 generalized anxiety disorder (GAD) patients were enrolled. Participants were assessed using the SIPS/SOPS and the FCQ scales. Analyses of covariance taking into account socio-demographic and clinical variables significantly different between groups were applied to compare FCQ and SOPS scores. Finally FCQ and SOPS principal component analysis was carried out in the schizophrenia spectrum group. SOPS scores were higher in the UHR, FES and MES groups compared to the GAD control group. Concordantly, FES and MES groups had a higher number of basic symptoms in comparison with the GAD group, whereas UHR did not differ from the control group. The largest number of correlations between BSs and psychotic symptoms was found in the GAD group. According to the principal component analysis (PCA) five factors were extracted, with the BSs loading on a unique factor. Our findings imply that the boundary between psychotic and non-psychotic conditions cannot be outlined on the basis of the presence/absence of basic and psychotic symptoms.