Prospective study of adolescents with subsyndromal psychosis: characteristics and outcome

The aim of this study was to examine the characteristics and outcome of adolescents with psychotic disorder not otherwise specified (PsyNOS) and brief psychotic disorder (BrPsy), two neglected subsyndromal diagnostic entities. As part of an ongoing, naturalistic study investigating adolescents considered to be prodromal for schizophrenia, 29 youngsters (mean age, 16.2 +/- 2.7 years) with PsyNOS or BrPsy were identified as theoretically at highest risk for schizophrenia and followed for over 6 (mean, 22.8 +/- 19.4) months. Contrary to our expectations, only 7 of the 26 individuals (27.0%) with follow-up data developed schizophrenia or schizoaffective disorder, and only 2 subjects (7.7%) retained their diagnosis of BrPsy/PsyNOS. The most frequent other diagnoses at follow-up were mood disorders (34.6%), personality disorders (11.5%), and obsessive-compulsive disorder (7.7%). Regarding severity of outcome, 38.5% of the patients progressed to a syndromal psychotic disorder, 23.1% continued to have attenuated positive symptoms, and 38.4% improved to having attenuated negative symptoms only, or no positive or negative symptoms. BrPsy was associated with lower maximum levels of negative symptoms (p = 0.02) and higher likelihood of symptom remission (p = 0.02). This study indicates that psychotic symptoms not fulfilling criteria for schizophrenia or a psychotic mood disorder are unreliable predictors of a syndromal psychotic disorder outcome at 2 years. Long-term studies of PsyNOS and BrPsy are needed to clarify where these disorders fall in the developmental course of schizophrenia.