Features of acute and transient psychotic disorders

Little is known about acute and transient psychotic disorders (ATPD), a diagnostic category introduced with ICD-10.

To determine the clinical and sociodemographic features, course and outcome of ICD-10 ATPD in a prospective and longitudinal study.

We recruited all consecutive inpatients fulfilling the ICD-10 criteria of ATPD during a 5-year period. Demographic and clinical features were systematically evaluated and follow-up investigations were carried out at an average of 10 years after onset of the disorder using standardized instruments.

ATPD patients represented 8.5% of all inpatients with non-organic psychotic disorders. ATPD were characterized by female preponderance. In two-thirds of the cases a typical polymorphic symptomatology was found. In spite of the fact that the possibility of relapse within 5 years was high, the psychopathological and social outcome for most of the patients was very favourable. Schizophrenic episodes during follow-up were rare (7.7% of patients), but a strictly monomorphous course (ATPD episodes only) from index episode to the end of the prospective follow-up was found in only 53.9% of the patients.

ATPD are not a sharply demarcated and unchanging nosological entity. Nevertheless, the present data support a delineation of ATPD as a diagnostic category with specific clinical features and with a usually favourable prognosis. Further research on the topic is necessary.