Syndrome shift in the long-term course of schizoaffective disorders.

Seventy-two patients diagnosed as having schizoaffective disorders (Cologne study) were investigated with regard to syndrome shift. During long-term follow-up (mean 25.6 years) they had 400 episodes (the duration of an episode being defined as the time between the beginning and end of inpatient or inpatient-like treatment). A total of 61% of the patients had a polymorphous course, i.e. displayed more than one type of episode. The first syndrome shift was found in the early stages of the course (in 61% of the cases as early as the second episode, in 84% at latest by the third episode). Using diagnostic criteria considering the longitudinal approach, 88% of schizoaffective disorders could be definitively diagnosed as such at the latest by the second episode. The only difference in the course between polymorphous and monomorphous (with only one type of episode) schizoaffective disorders was that the former relapsed more frequently. On the basis of the findings of the present study we suggest a longitudinally based dichotomy of schizoaffective disorders into bipolar and unipolar.