BACKGROUND This study in North India compared acute brief psychosis--defined by acute onset, brief duration and no early relapse--with other remitting psychoses, over a 12-year course and outcome.
METHOD In a cohort of incident psychoses, we identified 20 cases of acute brief psychosis and a comparison group of 43 other remitting psychoses based on two-year follow-up. Seventeen people (85%) in the acute brief psychosis group and 36 (84%) in the comparison group were reassessed at five, seven and 12 years after onset, and were rediagnosed using ICD-10 criteria.
RESULTS At 12-year follow-up, the proportion with remaining signs of illness was 6% (n = 1) for acute brief psychosis versus 50% (n = 18) for the comparison group (P = 0.002). Using ICD-10 criteria, the majority in both groups were diagnosed as having schizophrenia.
CONCLUSIONS Acute brief psychosis has a distinctive and benign long-term course when compared with other remitting psychoses. This finding supports the ICD-10 concept of a separable group of acute and transient psychotic disorders. To effectively separate this group, however, the ICD-10 criteria need modification.