Characteristics and heterogeneity of schizoaffective disorder compared with unipolar depression and schizophrenia – a systematic literature review and meta-analysis

Functional outcome and service engagement in major depressive disorder with psychotic features: comparisons with schizophrenia, schizoaffective disorder and bipolar disorder in a 6‐year follow‐up of the Cavan‐Monaghan First Episode Psychosis Study (CAMFEPS)

“…In summary, on the background of an extensive literature on long‐term outcome in SZ, SA, and BD in terms of positive, negative, and general symptoms, functionality, QoL, and service engagement across various diagnostic combinations at varying stages of illness, the present prospective findings inform on comparative long‐term outcome in MDDP. Importantly, apparent differences in PANSS psychopathology, functioning, QoL, and service engagement between diagnoses were quantitative rather than qualitative, with considerable overlap between them.…”

“…However, this literature derives primarily from studies on the diagnostic category of schizophrenia (SZ), while contemporary research is increasingly involving broader, dimensional concepts of psychosis . To the forefront of such research is the nosological, clinical, and biological relationship between SZ and bipolar I disorder (BD), with the long‐standing conundrum of schizoaffective disorder (SA) continuing to receive consideration in this context . However, the most common psychotic diagnosis other than SZ and BD is a major depressive disorder with psychotic features (MDDP).…”

“…It is well recognized that SZ can be characterized by pervasive disability over multiple dimensions of functioning, with BD also characterized by considerable functional impairment, albeit perhaps to a somewhat lesser extent than for SZ . SA has commonly been included with SZ, such that fewer studies have addressed SA as a distinct category . In contrast, MDDP has received less attention, there being few long‐term follow‐up studies to date …”

“…[1][2][3][4] To the forefront of such research is the nosological, clinical, and biological relationship between SZ and bipolar I disorder (BD), 1,[4][5][6] with the long-standing conundrum of schizoaffective disorder (SA) continuing to receive consideration in this context. 7,8 However, the most common psychotic diagnosis other than SZ and BD is a major depressive disorder with psychotic features (MDDP). Although it constitutes the archetype for confluence between psychotic and affective dimensions of psychopathology, 9 MDDP (also known as psychotic depression 10 ) has received less attention in this context.…”

“…5,18 SA has commonly been included with SZ, such that fewer studies have addressed SA as a distinct category. 7,8,19 In contrast, MDDP has received less attention, there being few long-term follow-up studies to date. [20][21][22] On the presumption that mental health and associated services can provide beneficial interventions, engagement with such services is an essential element in optimizing outcome.…”