Schizoaffective disorder (SZA, SZD or SAD) is a mental or psychological disorder characterized by abnormal thought processes and deregulated emotions. The diagnosis is made when the patient has features of both schizophrenia and a mood disorder—either bipolar disorder or depression—but does not strictly meet diagnostic criteria for either alone.
The bipolar type is distinguished by symptoms of mania, hypomania, or mixed episode; the depressive type by symptoms of depression only.
Common symptoms of the disorder include hallucinations, paranoid delusions, and disorganized speech and thinking.
The onset of symptoms usually begins in young adulthood, currently with an uncertain lifetime prevalence because the disorder was redefined, but DSM-IV prevalence estimates were less than 1 percent of the population, in the range of 0.5 to 0.8 percent.
Diagnosis is based on observed behavior and the patient’s reported experiences.