Pseudoneurotic Symptoms in the Schizophrenia Spectrum: A Longitudinal Study of Their Relation to Psychopathology and Clinical Outcomes.

Background and hypothesis: Nonpsychotic symptoms (depression, anxiety, obsessions, etc.) are frequent in schizophrenia-spectrum disorders and are usually conceptualized as comorbidity or transdiagnostic symptoms. However, in twentieth century foundational psychopathological literature, many nonpsychotic symptoms with specific phenomenology (here termed pseudoneurotic symptoms) were considered relatively typical of schizophrenia. In this prospective study, we investigated potential associations of pseudoneurotic symptoms with diagnostic status, functional outcome as well as psychopathological dimensions of schizophrenia.

Study design: First-admitted patients (N = 121) diagnosed with non-affective psychosis, schizotypal disorder, or other mental illness were examined at initial hospitalization and 5 years later with a comprehensive assessment of psychopathology. Informed by the literature, we constructed scales targeting pseudoneurotic symptoms and other, more general, nonpsychotic symptoms.

Study results: Pseudoneurotic symptoms aggregated in schizophrenia-spectrum groups compared to other mental illnesses and occurred at similar levels at baseline and follow-up. They longitudinally predicted poorer social and occupational functioning in schizophrenia-spectrum patients over a 5-year-period but not transition to schizophrenia-spectrum disorders from other mental illnesses. Finally, the level of pseudoneurotic symptoms correlated with disorder of basic self at both assessments and with positive and negative symptoms at follow-up. The scale targeting general nonpsychotic symptoms did not show this pattern of associations.

Conclusions: The study supports that a group of nonpsychotic symptoms, ie, pseudoneurotic symptoms, are associated with schizophrenia-spectrum disorders and linked with temporally stable psychopathology, particularly disorder of the basic self. Their prospective association with social and occupational functioning needs replication.