"Transition" to Schizophrenia or Fluctuations within the Same Disorder?

BACKGROUND

To prevent or delay the onset of psychotic disorders or ameliorate their course, prodromal research has strived to identify and treat individuals at risk of developing psychosis. While this approach is laudable, it is, however, not entirely unproblematic from clinical and conceptual perspectives. For example, it remains unclear how we are to understand the development from a nonpsychotic, distressing condition such as schizotypal disorder to a psychotic disorder such as schizophrenia? The current terminology on the subject implies either a nonlinear jump ("conversion") or a more linear progression ("transition") from one disorder to another. To enrich our understanding of such diagnostic shifts, we examined the psychopathological pictures of patients who "transitioned" from schizotypal disorder to schizophrenia.

METHODS

From a larger study on psychopathology, we examined 40 patients who were diagnosed with schizotypal disorder at baseline. At 5-year follow-up, 30 patients maintained the diagnosis of schizotypal disorder, while 10 were re-diagnosed with schizophrenia. We examined detailed descriptions of the 10 patients who progressed to schizophrenia, comparing psychopathology and level of functioning.

RESULTS

The level of functioning decreased slightly from baseline to follow-up in 9 out of 10 patients. Eight patients had previously had micro-psychotic or psychotic experiences. All patients had self-disorders at baseline, and several patients had perceptual disorders. Nine patients had formal thought disorders at baseline. The progression is illustrated by 2 cases.

CONCLUSION

In this small study, we did not find any striking changes in any of the patients, neither in terms of psychopathological manifestations nor in terms of their level of functioning. Thus, rather than witnessing a genuine "conversion" or "transition" from schizotypal disorder to schizophrenia, we observed dimensional fluctuations within the same condition.