[Schizophrenia and depression]

Comparison of symptom-related and social role development between patients with schizophrenia, major depression and healthy controls provided insights into the untreated early course of the two disorders.

Symptoms, functional impairment and social disability were assessed and compared using the IRAOS and several other cross-sectional instruments in three samples.

At the early illness stages there was considerable overlap in the symptom patterns and impairments presented by persons with schizophrenia and severe depression. The two disorders did not diverge until later in the early illness course with the onset of psychotic symptoms. Depressive symptoms showed a maximum in the first psychotic episode and relapse episodes and decreased with the remitting episode. Due to differences in cognitive appraisal depressed patients reported more functional impairment and social disability than patients with schizophrenia did.

The early course of symptoms and social impairment in schizophrenia and depression seems to offer an opportunity to distinguish these disorders from variants of normal development fairly early. However, early diagnostic distinction and prediction of psychosis versus depression risk at the pre-psychotic prodromal stage do not seem promising due to the broad overlap in symptoms and impairment.