Schizophrenia, Adult

Definitions

The origin of the concept of “schizophrenia” is usually attributed to the German psychiatrist Emil Kraepelin. Kraepelin first used the term dementia praecox, or “premature dementia,” to distinguish it from other psychotic illnesses. In the early 20th century, the Swiss psychiatrist, Eugen Bleuler, argued that the term dementia is misleading because dementia suggests an irreversible progressive brain disease. Bleuler stated that the most salient characteristic of the disorder is not its onset nor its course, but the particular nature of its expression in cognitive functioning. He proposed the term schizophrenia to suggest the fragmentation of mental functioning and a split between thinking and feeling. Bleuler also argued that there is extensive variability among individuals who had obtained this label, suggesting that there is a group of similar but distinct disorders. He made the new name plural, the schizophrenias. Although the term schizophrenia is used in contemporary diagnostic systems, the diagnostic criteria and subtypes found in the Diagnostic and Statistical Manual (DSM) are largely those of Kraepelin.

DSM diagnosis of schizophrenia requires the presence of at least two types of psychotic symptoms, including hallucinations, delusions, irregular affect, and confusion or disorientation. Delusions alone are sufficient if they are “bizarre” (i.e., they could not possibly be true, as when a person believes he or she is dead). Symptoms must be present for at least 6 months, unless suppressed by treatment, and must be accompanied by impairment in personal and social functioning. The diagnosis may be elaborated by the assignment of subtypes, based on the specific quality of the symptoms and the course of the disorder.

Historically, the concept of schizophrenia, and of psychiatric diagnosis in general, has been criticized as not being grounded in theory. Furthermore, in contrast with medical diagnoses, psychiatric diagnoses do not identify the cause of the illness. Typically, two opinions in the contemporary psychiatry and psy-chopathology communities emerge when describing schizophrenia. The first is a traditional view that schizophrenia is a unitary disease much like Kraepelin originally described. The second view is that schizophrenia is a generic category for a variety of specific disorders that have little in common other than periods of psychosis. This ambiguity is reflected in the existence of a related diagnosis, schizoaffective disorder, in which characteristics of schizophrenia co-occur with characteristics of affective disorders, primarily bipolar disorder or depression. Even when diagnosed rigorously with the criteria provided by the DSM, people receiving the diagnosis of schizophrenia [Page 846]comprise a very heterogeneous group with respect to age of onset, symptoms and other behavioral expressions of illness, degree of functional disability and other characteristics. There is no clinical picture that is unique to or always present in “schizophrenia.”

For these reasons, the term schizophrenia has limited utility in clinical treatment, social policy, or mental health administration. This has stimulated widespread use of the more inclusive term serious mental illness (SMI), which captures schizophrenia's essential features, including a chronic course and severe functional disability.

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