A disturbance that lasts for at least 6 months and includes at least 1 month of active-phase symptoms (i.e., two [or more] of the following: delusions, hallucinations, disorganized speech, grossly disorganized or catatonic behavior, negative symptoms). Definitions for the Schizophrenia subtypes (Paranoid, Disorganized, Catatonic, Undifferentiated, and Residual) are also included in this section.
The individual with Schizophrenia may display inappropriate affect (e.g., smiling, laughing, or a. silly facial expression in the absence of an appropriate stimulus), which is one of the defining. features of the Disorganized Type. Anhedonia (mild depression) is common and is manifested by a loss. of interest or pleasure. Dysphoric mood may take the form of depression, anxiety, or anger. There may. be disturbances in sleep pattern (e.g., sleeping during the day and nighttime activity or. restlessness). The individual may show a lack of interest in eating or may refuse food as a. consequence of delusional beliefs. Often there are abnormalities of psychomotor activity (e.g.,. pacing, rocking, or apathetic immobility). Difficulty concentrating is frequently evident and may. reflect problems with focusing attention or distractibility due to preoccupation with internal. stimuli.
Although basic intellectual functions are classically considered to be intact in Schizophrenia, some indications of cognitive dysfunction are often present. The individual may be confused or disoriented or may have memory impairment during a period of exacerbation of active symptoms or in the presence of very severe negative symptoms. Lack of insight is common and may be one of the best predictors of poor outcome, perhaps because it predisposes the individual to noncompliance with treatment. Depersonalization, derealization, and somatic concerns may occur and sometimes reach delusional proportions. Motor abnormalities (e.g., grimacing, posturing, odd mannerisms, ritualistic or stereotyped behavior) are sometimes present. The life expectancy of individuals with Schizophrenia is shorter than that of the general population for a variety of reasons.
Suicide is an important factor, because approximately 10% of individuals with Schizophrenia commit suicide. Risk factors for suicide include being male, age under 30 years, depressive symptoms, unemployment, and recent hospital discharge. There is conflicting evidence with regard to whether the frequency of violent acts is greater than in the general population.
- Schizophreniform Disorder
- Characterized by a symptomatic presentation that is equivalent to Schizophrenia except for its duration (i.e., the disturbance lasts from 1 to 6 months) and the absence of a requirement that there be a decline in functioning.
- Schizoaffective Disorder
- A disturbance in which a mood episode and the active-phase symptoms of Schizophrenia occur together and were preceded or are followed by at least 2 weeks of delusions or hallucinations without prominent mood symptoms.
Schizophrenia is warranted only if prominent delusions or hallucinations are present for at least a month. The characteristic symptoms of Schizophrenia involve a range of cognitive and emotional dysfunctions that include perception, inferential thinking, language and communication, behavioral monitoring, affect, fluency and productivity of thought and speech, hedonic capacity, volition and drive, and attention. The diagnosis involves the recognition of a constellation of signs and symptoms associated with impaired occupational or social functioning.