Major systems of classifying psychiatric disorders are revised to incorporate new knowledge and enhance clinical utility. With specific reference to revisions from DSM-IV to DSM-5, the changes in the section on schizophrenia spectrum and other psychotic disorders were made to address:
1. Inadequate presentation of the heterogeneity of clinical syndromes
2. Treatment of schizoaffective disorder as an episode diagnosis with unclear separation from schizophrenia
3. Poor reliability and low diagnostic stability of schizoaffective disorder
4. Variable definitions and discrepant treatment of catatonia across disorders in DSM-IV
5. The limited role and validity of schizophrenia subtypes
6. Inadequate classification for early detection of potential psychoses
Relevant revisions in DSM-5 eliminate the classic subtypes of schizophrenia and add unique psychopathological dimensions, as well as a scale to measure each of these dimensions across all psychotic disorders; provide a more precise definition of the boundary between schizophrenia and schizoaffective disorder; and add a new category—attenuated psychosis syndrome. The latter is a condition for further study in Section 3.
In this article, we discuss the implications of these changes for clinical practice.
Better explanation of the heterogeneity of schizophrenia
Schizophrenia and other psychotic disorders are characterized by several psychopathological domains, each with distinctive courses, patterns of treatment-response, and prognostic implications. The 5 characteristic (Criteria A) symptoms vary among patients as does symptom severity within each syndrome at different stages of illness. Individualized treatment depends on identifying which aspects of pathology are present. To facilitate deconstructing syndromes into symptom dimensions, Section 3 provides a 5-point scale for each of the Criteria A symptoms (delusions, hallucinations, negative symptoms, disorganization, psychomotor) and for cognitive impairment, depression, and mania.1
Measurement of the severity of symptoms throughout the illness can provide useful information about the nature of the illness in a particular patient and can aid in assessing the specific impact of treatment. As a simple rating scale, it encourages clinicians to assess and track changes in the severity of these dimensions in each patient with schizophrenia and use this information to individualize measurement-based treatment.2
Dr. Tandon is Professor of Psychiatry at the University of Florida, Gainesville, FL. Dr. Carpenter is Professor of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Catonsville, MD. The authors report no conflicts of interest concerning the subject matter of this article.
1. Barch DM, Bustillo J, Gaebel W, et al. Logic and justification for dimensional assessment of symptoms and related phenomena in psychosis: relevance to DSM-5. Schizophr Res. 2013;150:15-20.
2. Tandon R, Targum SD, Nasrallah HA, Ross R. Strategies for maximizing clinical effectiveness in the treatment of schizophrenia. J Psychiatr Pract. 2006;12:348-363.
3. Tandon R, Maj M. Nosological status and definition of schizophrenia. Some considerations for DSM-V and ICD-11. Asian J Psychiatry. 2008;1:22-27.
4. Korver-Nieberg N, Quee PJ, Boos HB, Simons CJ. The validity of the DSM-IV diagnostic classification system of non-affective psychosis. Aust N Z J Psychiatry. 2011;45:1061-1068.
5. Fusar-Poli P, Bonoldi I, Yug AR, et al. Predicting psychosis: meta-analysis of transition outcomes in individuals at high clinical risk. Arch Gen Psychiatry. 2012;69:220-229.
6. Tandon N, Shah J, Keshavan MS, Tandon R. Attenuated psychosis and the schizophrenia prodrome: current status of risk identification and psychosis prevention. Neuropsychiatry. 2012;2:345-353.
7. Tsuang MT, van Os J, Tandon R, et al. Attenuated psychosis syndrome in DSM-5. Schizophr Res. 2013;15:31-35.
8. Tandon R, Bruijnzeel D, Rankupalli B. Does change in definition of psychotic symptoms in diagnosis of schizophrenia in DSM-5 affect caseness. Asian J Psychiatry. 2013;6:330-332.
9. Malaspina D, Owen M, Heckers S, et al. Schizoaffective disorder in the DSM-5. Schizophr Res. 2013; 150:21-25.
10. Fusar-Poli P, Cappucciati M, Rutigliano G, et al. Diagnostic stability of ICD/DSM first episode psychosis diagnoses: meta-analysis. Schizophr Bull. March 15, 2016; Epub ahead of print.
11. Heckers S, Tandon R, Bustillo J. Catatonia in the DSM. Shall we move or not? Schizophr Bull. 2010;36:205-207.
12. Tandon R, Heckers S, Bustillo J, et al. Catatonia in DSM-5. Schizophr Res. 2013;150:25-30.
13. Gaebel W, Zielasek J, Cleveland HR. Psychotic disorders in ICD-11. Asian J Psychiatry. 2013;6:263-265.