Stability of diagnosis: a 20-year retrospective cohort study of Israeli psychiatric adolescent inpatients.

Outcome according to diagnosis and stability of diagnosis were investigated in a follow-back study of 351 adolescents with various psychiatric disorders hospitalized in a closed psychiatric ward. The duration of follow-back was 15-19 years. All diagnoses were based on the ICD-9. Data were collected from the Health Ministry registry and, in the patients who could be located, by structured telephone interview. Special attention was directed at the diagnosis of transient adolescent psychosis (TAP) vs. schizophrenia and prognostic indicators of suicide. The results showed that the most stable diagnosis was anxiety disorder. The stability of the different diagnoses over time was greater between the second and last admission than between the first and last (for patients with three or more admissions). Number of hospitalizations correlated negatively with prognosis. TAP at second admission was an unstable diagnosis; 66% of these patients had a final diagnosis of schizophrenia. However, patients with a diagnosis of TAP at first admission had a higher predictive index score and a higher outcome score than schizophrenic patients. TAP appeared to be a valid diagnostic entity, distinguishable from schizophrenia in course, frequency of suicidal behaviour and social-occupational outcome. Suicide victims had a higher cumulative length of stay than age- and sex-matched non-suicidal patients. Fifty per cent of the suicide victims had a final diagnosis of schizophrenia, compared to 30 per cent for the whole sample. In conclusion, these findings indicate that TAP is associated with a relatively good prognosis and should probably be differentiated from schizophrenia. Further retrospective and prospective studies of adolescent psychiatric inpatients may help delineate the nature and course of psychosis and other psychopathology in this age group. Copyright 2001 The Association for Professionals in Services for Adolescents.