Background: Both retrospective and prospective studies have identified a broad spectrum of "prodromal" symptoms, but their relationship to those of frank psychosis remains largely unexplored.
Method: In 73 successive hospitalized patients with schizophrenia in the first or second psychotic episode and with duration of illness 3 years or less from the onset of psychosis, Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision, Axis I diagnoses were made. In addition, within the first 5 days from the psychotic episode's onset, symptom severity was assessed with the Positive and Negative Syndrome Scale (PANSS).
Results: Stepwise regression analyses showed that 8 prodromal symptoms carried an increased risk for high total PANSS and the components of the PANSS scores, independently of sex; 1 symptom was associated with mild psychopathology. However, the categories of negative- and positive-disorganization prodromal symptoms were not associated with the corresponding PANSS components. Similar findings were observed in the nonparanoid patients, whereas in the paranoid, only 2 nonspecific symptoms were associated with high PANSS psychopathology. In addition, there were significant associations between number of prodromal symptoms and total PANSS and the subscales positive and general scores in the patients with the nonparanoid subtypes, but there were not such associations in those with the paranoid.
Conclusions: Several prodromal symptoms, as well as the number of symptoms, are associated with the severity of the psychopathology of frank psychosis. In the nonparanoid subtypes there is a continuance in the transition from the prepsychotic to the psychotic stage, whereas in the paranoid, the transition appears to be disrupted.