Because the person has symptoms of both illnesses, it is sometimes not possible to distinguish between schizophrenia and bipolar disorder. In addition, some people’s symptoms change over time. First they appear as typical symptoms of schizophrenia or bipolar disorder, but a year later they show clear signs of the other illness.
Schizoaffective disorder is form of psychosis that falls between a diagnosis of schizophrenia and bipolar disorder.
People with a schizoaffective disorder are treated for the specific symptoms they have. The cause and outcome of the diseases is similar to those of schizophrenia and bipolar disorder.