Polymorphous Affective Psychosis: Grounds for Diagnosis of Bipolar I Disorder, Schizophrenia, or Separate Nosological Form

Background: According to some data in more than 50% of patients, suffering from bipolar disorder (BD) for a long time, cases of repeated changes in the diagnosis of affective disorder for schizophrenia are known in clinical practice. These observations served as the basis for the theory of the “psychopathological continuum,” referred to as “the phenomenon of overlapping disorders of the affective and schizophrenic spectra”. The objective of the investigation was to study the phenomenon of “syndromal shift” in a diagnosed bipolar I disorder with a long course and the presence of affective and schizophreniform episodes. Patients and Methods: A total of 91 patients with diagnoses of bipolar I disorder were examined, whereas during the illness in at least one episode psychotic symptoms incongruent with affect were observed, but the diagnosis did not change during the course of the disease. The duration of follow-up observation was 12–15 years. Three groups of patients were identified as follows: with a predominance of affective, schizoaffective, or schizophreniform episodes. The analysis of episodes and comparison of these groups was carried out using psychometric scales (Cornell Dysthymia Rating Scale, CDRS; Young Mania Rating Scale, YMRS; Positive and Negative Syndrome Scale, PANSS; Global Assessment of Functioning, GAF). Results: this study examined the characteristics, similarities, and differences of bipolar disorder I episodes based on the analysis of the long-term follow-up observation of patients. Diagnostic criteria were developed, taking into account the dominance of different types of episodes during the course of the disease. The course was polymorphic with not only affective phases, but also with schizoaffective and schizophreniform episodes, occurring with varying frequency. Significant differences were found in cases of the course of the disease with a predominance of mood disorders with schizoaffective and schizophreniform episodes. This was especially clear in relation to such parameters as the age of the first appointment with a psychiatrist and the quality of global functioning. Conclusions: despite the phenomenological similarity, the course of bipolar disorder I, reveals stable differences between types with a predominance of affective, schizoaffective, or schizophreniform episodes. The syndromal shift and the zone of overlapping disorders are formed as a result of the “antagonistic influence” of the “mood disorders” prototypes and schizophreniform manifestations. The choice of diagnostic strategy should take into account BD polymorphism in order to ensure adequate treatment and prevention of relapses, since the boundaries of these diagnostic categories are labile and permeable.