Schizoaffective disorder is a severe mental illness in which the patient has symptoms of both schizophrenia and a mood (affective) disorder, but fails to meet the diagnostic criteria for either illness alone. There are two main types of schizoaffective disorder: bipolar type (those with bipolar symptoms) and depressive type (those with depressive symptoms). The bipolar type is more common in younger patients, while the depressive type is more common in older patients. Symptoms vary greatly from person to person with some patients experiencing only mild symptoms while others have very extreme cases.

To receive a diagnosis for schizoaffective disorder rather than schizophrenia, the patient must have a depressive or manic episode lasting longer than 50% of the total illness time. To get a diagnosis of schizoaffective disorder instead of bipolar disorder, psychosis must occur while not in a depressive or manic state. People with a schizoaffective diagnosis have a better prognosis than those with schizophrenia, but a worse prognosis than those with bipolar I disorder.

Since schizoaffective disorder features symptoms of two separate mental disorders, the disease is often misdiagnosed, with some patients being diagnosed with schizophrenia and others diagnosed with bipolar disorder. This makes it difficult to estimate how many people actually have schizoaffective disorder. However, experts estimate that the disease affects about one in every 200 people — about half the risk of schizophrenia.

Risk for schizoaffective disorder is determined by both genetics and environmental factors. People with a first-degree relative with schizoaffective disorder, schizophrenia or bipolar disorder are at greater risk.

Example: Charlie suffers from strong delusions, hallucinations and long bouts of mania, followed by severe depression. He was initially diagnosed with bipolar disorder, but over time his doctor realized he had schizoaffective disorder.