Schizoaffective Disorder - History

History

The term schizoaffective psychosis was introduced by the American psychiatrist Jacob Kasanin in 1933 to describe an episodic psychotic illness with predominant affective symptoms, that was thought at the time to be a good-prognosis schizophrenia. Kasanin's concept of the illness was influenced by the psychoanalytic teachings of Adolf Meyer and Kasanin postulated that schizoaffective psychosis was caused by "emotional conflicts" of a "mainly sexual nature" and that psychoanalysis "would help prevent the recurrence of such attacks." He based his description on a case study of nine individuals.

Other psychiatrists, before and after Kasanin, have made scientific observations of schizoaffective disorder based on assumptions of a biological and genetic etiology of the illness. In 1863, German psychiatrist Karl Kahlbaum (1828–1899) described schizoaffective disorders as a separate group in his vesania typica circularis. Kahlbaum distinguished between cross-sectional and longitudinal observations. (Cross-sectional refers to observation of a single, specific episode of the illness, for example, one episode of psychotic depression; while longitudinal refers to long-term observation of many distinct episodes often occurring over the span of years.) In 1920, psychiatrist Emil Kraepelin (1856–1926), the founder of contemporary scientific psychiatry, observed a "great number" of cases that had characteristics of both groups of psychoses that he originally posited were two distinct and separate illnesses, dementia praecox (now called schizophrenia) and manic depressive insanity (now called bipolar disorder and recurrent depression).

Kraeplin acknowledged that "there are many overlaps in this area", that is, the area between schizophrenia and severe mood disorders. In 1959, psychiatrist Kurt Schneider (1887–1967) can be said to have been the first to begin to conceptualize the different forms that schizoaffective disorders can take since he observed "concurrent and sequential types". (The concurrent type of illness he referred to is a longitudinal course of illness with episodes of mood disorder and psychosis occurring predominantly at the same time; while his sequential type refers to a longitudinal course predominantly marked by alternating mood and psychotic episodes.) Schneider described schizoaffective disorders as "cases in-between" the traditional Kraepelinian dichotomy of schizophrenia and mood disorders.

The historical phenomenological observation that schizoaffective disorder is an overlap of schizophrenia and severe mood disorders has more recently been assumed to be explained by genes for both illnesses being present in individuals with schizoaffective disorder. In support of this assumption, recent research shows that schizophrenia and severe mood disorders appear to share common genes and polygenic variations also.

Schizoaffective disorder was included as a subtype of schizophrenia in DSM-I and DSM-II, though research showed a schizophrenic cluster of symptoms in individuals with a family history of mood disorders whose illness course, other symptoms and treatment outcome were otherwise more akin to bipolar disorder than to schizophrenia. DSM-III placed schizoaffective disorder in "Psychotic Disorders Not Otherwise Specified" before being formally recognized in DSM-III-R. DSM-III-R included its own diagnostic criteria as well as the subtypes, bipolar and depressive. In DSM-IV, published in 1994, schizoaffective disorders belonged to the category "Other Psychotic Disorders" and included almost the same criteria and the same subtypes of illness as DSM-III-R, with the addition of mixed bipolar symptomatology.