Manic-depressive psychosis (also referred to as bipolar disorder or manic depression) and schizoaffective disorder are actually two different mental disorders, although they bear similarities and their symptoms overlap.
Schizoaffective disorder (SD) is a somewhat controversial diagnosis. It displays symptoms of both bipolar disorder and schizophrenia. It has the extreme mood swings of bipolar disorder — with alternating bouts of depression and mania (euphoria) – and some of the psychotic features of schizophrenia, such as delusions, hallucinations, paranoia and distorted perceptions.
Doctors often back into a diagnosis of SD when the patient’s illness doesn’t quite match the defined characteristics of either schizophrenia or bipolar disorder. Further frustrating a clear diagnosis is the possibility that the patient may have bipolar disorder with psychotic symptoms. This condition closely resembles SD but the psychotic symptoms usually occur during the manic or depressed episodes. What makes schizoaffective disorder distinct is that the patient must experience at least two weeks of psychotic symptoms only, without mania or depression.
It’s a fine distinction that may not seem terribly important at first glance. It’s possible, though, that it may lead us to better treatments in terms of learning which medicines and combinations to use. Perhaps it will also help in the development of more targeted forms of psychotherapy to treat schizoaffective disorder.