Stability of diagnosis in schizophrenia

The authors investigated factors associated with change in diagnosis from schizophrenia to other disorders and from other disorders to schizophrenia, as well as the time elapsed before diagnostic change.

Using a longitudinal study design, they examined data collected over a 7-year period at an urban acute care psychiatric hospital. The subjects were 936 inpatients who had been hospitalized at least four times during the study period. Changes to and from a diagnosis of schizophrenia over the 7 years were investigated in relation to demographic variables, socioeconomic factors, and clinical features.

Fifty-six (21.9%) of the 256 subjects with a diagnosis of schizophrenia at the beginning of the study received a different diagnosis during a subsequent hospitalization. Females and subjects of Hispanic origin were more likely to undergo a diagnostic change from schizophrenia. Two hundred twenty-three (32.8%) of the 680 subjects who initially had a diagnosis other than schizophrenia were later diagnosed with schizophrenia. Males and African Americans had significantly higher rates of change to a diagnosis of schizophrenia than females and other ethnic groups. In addition, socio-economic factors and clinical features were associated with a change in diagnosis from another disorder to schizophrenia.

The diagnosis of schizophrenia, in current practice, is not static. Patients' characteristics interact with longitudinal clinical changes to produce shifts in diagnosis. Longitudinal follow-up is necessary to validate diagnoses.