Longitudinal follow-up in acute and transient psychotic disorders and schizophrenia.

We prospectively studied the long-term course of individuals with acute and transient psychotic disorders and a control group with positive schizophrenia matched for age and gender. Follow-up investigations using standardised instruments were performed at three time-points covering 7 years after the index episode or 12 years after the first episode. During follow-up, those with positive schizophrenia experienced a deterioration in their general functioning whereas those with acute and transient psychotic disorders retained their high level of functioning. At the end of the observation period, 12 out of 39 (31%) of those with acute and transient psychotic disorders were functioning well without medication compared with 0 out of 38 with positive schizophrenia.