The heterogeneous course of schizophrenia.

Findings on the course and outcome of schizophrenia, the limitations of Kraepelin's opinion, and data supporting a continuum hypothesis of endogenous psychoses are presented. The European long-term investigations, the Zürich, Lausanne and Bonn studies are consistent with the view that diagnoses must be made independently of outcome; nearly a quarter show full psychopathological and 56% a social remission. Several factors are relevant to the long-term course and outcome. In the Bonn Study, 43% of subjects showed long-term remission, with only a mild deficit state ('pure defect') consisting of dynamic and cognitive basic symptoms, and 35% revealed characteristic schizophrenic residues. Eighty-seven per cent were living at home permanently at the most recent follow-up; 56% were socially recovered, i.e., fully employed, yet only 38.6% were at their previous occupational level. Twelve course types could be differentiated and were ranked according to social remission rate. The results led to a revision of classical descriptions of an incessant progression of schizophrenia. The outcome is largely independent of the duration of illness; there is no increasing deterioration in the later decades of the disease, often showing a trend toward improvement (the 'second, positive bend'), even 20-40 years after onset. According to Zubin, the results of the European long-term studies and the Vermont Study have revolutionized our knowledge about schizophrenia and emancipated it from the yoke of inevitable chronicity. The findings of the Bonn Study, the first systematic study of prodromes, and of the prospective basic symptom-oriented study on the early diagnosis of schizophrenia led, in parallel with the gradual development of the basic symptom concept, to a new view of the evolution of schizophrenia.