Is schizoaffective disorder a distinct categorical diagnosis? A critical review of the literature

Abstract

Considerable debate surrounds the inclusion of schizoaffective disorder in psychiatric nosology. Schizoaffective disorder may be a variant of schizophrenia in which mood symptoms are unusually prominent but not unusual in type. This condition may instead refl ect a severe form of either major depressive or bipolar disorder in which episode-related psychotic symptoms fail to remit completely between mood episodes. Alternatively, schizoaffective disorder may refl ect the co-occurrence of two relatively common psychiatric illnesses, schizophrenia and a mood disorder (major depressive or bipolar disorder). Each of these formulations of schizoaffective disorder presents nosological challenges because the signs and symptoms of this condition cross conventional categorical diagnostic boundaries between psychotic disorders and mood disorders. The study, evaluation, and treatment of persons presently diagnosed with schizoaffective may be more usefully informed by a dimensional approach. It is in this context that this article reviews and contrasts the categorical and dimensional approaches to its description, neurobiology, and treatment. Based on this review, an argument for the study and treatment of this condition using a dimensional approach is offered.

Schizoaffective disorder and metabolic syndrome: A meta-analytic comparison with schizophrenia and other non-affective psychoses

“…Although it may share several clinical, neurobiological and genetic features with SCZ and ONAP (Abrams et al, 2008), SD is a distinct severe mental disorder, with a categorical nosographic validity between schizophrenia and pure mood disorders (Correll, 2011;Bobes et al, 2012). People with SD may be more prone to develop MetS because of the co-occurrence of depressive and psychotic symptoms.…”

Negative Appraisal and Traumatic Stress Symptoms in Community Clients With Serious Mental Illness

“…In the current study, we tested the hypothesis that negative appraisals of the self, the world, and selfblame as measured by the PTCI would account for significant variance in posttraumatic stress symptoms when controlling for other key factors known to correlate with posttraumatic stress symptoms. We controlled for depression and psychosis because people with schizophrenia spectrum and major mood disorders can experience both types of symptoms to some degree (Abrams, Rojas, & Arciniegas, 2008;Baynes, Mulholland, Cooper, et al, 2000). We controlled for substance abuse given high rates of co-morbidity in this population (Drake & Mueser, 2002).…”

Substance Use Motives in People With Severe Mental Illness: Comparisons Among Four Diagnostic Groups

“…The greater mood disturbances in clients with bipolar disorder (e.g., mania in addition to depression) might account for the more pronounced difference between degree of coping motives in that diagnostic group and those with schizophrenia. Given that those with schizoaffective disorder showed no difference with any group with regard to motives, the range of both cognitive and mood disturbances in this group (Abrams, Rojas, & Arciniegas, 2008) could have masked any clear differences in substance use motives among diagnostic groups. Future studies should examine differences in symptoms among groups of people with severe mental illnesses while controlling for diagnoses, as people with severe mental illnesses share, to one degree or another, a common range of symptoms of psychosis and mood disturbances.…”

“…The findings regarding schizoaffective disorder showed some overlap in findings with both schizophrenia and major mood disorders given the combination of both thought processing and emotion regulation, which mark this controversial disorder (Abrams et al, 2008). ANOVA showed no significant difference between schizophrenia and schizoaffective disorder on any measure.…”