Objective: The nosological status of schizoaffective disorders is still unclear. The aim of the present study was to compare ICD-10 schizoaffective disorders to schizophrenia and affective disorders with respect to the clinical picture and the long-term outcome.
Method: Two hundred and forty-one first-admitted inpatients from the years 1980–1982 who fulfilled the ICD-10 criteria for schizophrenia, schizoaffective or affective disorders were included. Patients were examined at the time of first hospitalization and then followed-up after 15 years.
Results: With respect to the clinical picture at the time of first hospitalization ICD-10 schizoaffective disorders were distinguishable from both schizophrenia and affective disorders. However, with respect to the long-term outcome ICD-10 schizoaffective disorders had a prognosis similar to that of affective disorders.
Conclusion: Differing prognosis implies that schizoaffective disorders should be distinguished from schizophrenia and suggests their subcategorization under affective disorders.