Proposed changes in the diagnostic criteria of schizophrenia in DSM-5

Rajiv TABDOB

Professor of Psychiatry,University of Florida,Gainesville,FL,United States

E-mail:tandon@ufl.edu

Proposed changes in the diagnostic criteria of schizophrenia in DSM-5

Rajiv TABDOB

Professor of Psychiatry,University of Florida,Gainesville,FL,United States

E-mail:tandon@ufl.edu

Our current constructof schizophrenia derives from Em il Kraepelin’s formulation of dementia praecox in the late 19th century and the contributions of Eugen Bleuler and Kurt Schneider in the early and middle of the 20th century,respectively. Kraepelin identified dementia praecox principally based on course（deteriorating）,and outcome（demence or"mental dullness"）.Eugen Bleuler renamed this condition"schizophrenia"and delineated a set of fundamental symptoms which he considered unique to schizophrenia and always present,but considered the course and outcome to be variable.Kurt Schneider believed that impairment of empathic communication was the fundamental defect in schizophrenia and defined 11 first-rank symptoms which he considered to be diagnostic of schizophrenia.Current definitions of schizophrenia（including DSM-IV）［1］all incorporate Kraepelinian chronicity,Bleulerian negative symptoms,and Schneiderian positive symptoms.

W hat are the major limitations in our current construct of schizophrenia and what are the current DSM-5 efforts to address them［2-4］？

Lim itations in the construct of schizophrenia，circa 2011

First,many etiological factors and pathophysiological processes appear relevant to what w e consider schizophrenia and it is almost certain that our construct of schizophrenia encompasses not one but several diseases［5-7］.Second,the boundary between schizophrenia and schizoaffective disorder is im precisely defined and,thus,a significant proportion of individuals with schizophrenia with some mood symptoms inappropriately receive a diagnosis of schizoaffective disorder；this problem is compounded by the poor reliability and low diagnostic stability of a diagnosis of schizoaffective disorder［2,3,8］.Third,the current classic subtypes of schizophrenia provide a very poor description of the enormous heterogeneity of this condition；subtype stability is low and only the paranoid and undifferentiated subtypes are utilized with some frequency.Fourth,the prom inence that continues to be given to Schneiderian first-rank symptoms in diagnostic criteria（"bizarre"delusions or"special" hallucinations）appears m isp laced.Fifth,the current construct of schizophrenia is inadequate in describing the major psychopathological dimensions of the condition or stages in its evolution［8,9］.Finally,the clinical construct of schizophrenia as currently defined does not match neurobiological markers and genetic findings or specific pharmacological treatment provided［6,7,10］.

Current DSM-5 proposal for the definition of schizophrenia［4］

The currently proposed DSM-5 revisions［4］to the DSM-IV［1］definition of schizophrenia attem pt to address these lim itations in the construct of schizophrenia.Five proposed changes are briefly summarized below.

1. Schizophreniasyndrome

Changes proposed in the diagnostic criteria of schizophrenia are modest.Continuity with the DSM-IV criteria is broadly maintained.Two changes are proposed in‘criterion A’（active phase symptom s）:

①Elim ination of special treatment of bizarre delusions and other Schneiderian first-rank symptoms.In DSM-IV,only one criterion A symptom is required if it is a bizarre delusion or hallucination.Because Schneiderian first-rank symptoms do not have diagnostic specificity,these‘positive symptoms’w ill be treated like any other symptoms with regard to their diagnostic relevance.

②Requirement that at least one of the two symptoms needed to meet criterion A be delusions, hallucinations or disorganized thinking.These are core"positive sym ptoms"diagnosed with high reliability and m ight reasonably be considered necessary for a reliable diagnosis of schizophrenia.

2. Subtypes

The current DSM-5 proposal for describing schizophrenia advocates that the DSM-IV subtypes of schizophrenia be eliminated.These subtypes have limited diagnostic stability,low reliability, poor validity,and little clinical utility.Furthermore,except for the paranoid and undifferentiated subtypes,the other subtypes are rarely utilized in most mental healthcare systems.As show n in Professor xu’s discussion（below）this is also true in China:91 percent of almost 19,000 patients discharged from the Shanghai Mental Health Center with a diagnosis of schizophrenia from 2001-2010 w ere classified as undifferentiated subtype［11］.

3. Schizoaffectivedisorder

Characterization of patients with both psychotic and mood symptoms either concurrently or at different points during their illness has always been a source of controversy.Whereas,in DSM-I and DSM-II,a diagnosis of schizophrenia,schizo affective subtype,was generally recommended for such patients,in DSM-III,this recommendation was reversed with a strong mood disorder bias-schizophrenia was to be diagnosed only in the absence of prom inent mood symptoms.Furthermore,in DSMIII,a diagnosis of schizoaffective disorder w as very strongly discouraged；it was the only condition in DSM-III w ithout operational criteria.Schizoaffective disorder saw a revival in DSM-III-R and DSMIV.At present,in many mental healthcare system s almost a third of patients with psychotic symptom s receive a diagnosis of schizoaffective disorder. One of the crucial changes in the definition of schizoaffective disorder from DSM-III to DSM-IV w as that itmoved from being a lifetime diagnosis to a cross-sectional diagnosis；thas is,in DSM-IV only mood and psychotic symptom s in the current episode are considered while the longitudinal course of these symptoms in the individual’s life history is ignored.In the current DSM-5 proposal,an effort is made to im prove reliability of this condition by providing more specific criteria and it is re-conceptualized as a longitudinal diagnosis.Tow ards this end,the most significant change is proposed in criterion C of schizoaffective disorder［4］.

4. Psychopathologicaldimensionsofschizophrenia

It is clear that schizophrenic illness is characterized by several psychopathological domains that have a distinctive course,patterns of treatment-response,and prognostic im plications.The relative severity of these sym ptom dimensions（positive, negative,depressive,manic,disorganization,motor,and cognitive）vary across patients and within patients at different stages of their illness.Measuring the severity of these symptom dimensions through the course of illness in the context of treatment can provide useful information to the clinician about the nature of schizophrenic illness in a particular patient and about the specific impact of treatment on different aspects of the patient’s illness（analogous to measuring pulse,temperature,blood pressure,respiratory rate,etc.）.In addition to their clinical utility,the dimensional measurements of schizophrenia proposed for DSM-5 should prove useful from a research perspective；this type of dimensional information will facilitate studies on etiology and pathogenesis that cutacross current diagnostic categories.

5. Attenuatedpsychosissyndrome

It is believed that the still unsatisfactory outcome of schizophrenia in a significant proportion of individuals with the disorder is because we identify the illness and initiate treatment late in the course of the illness after a substantial amount of damage has already occurred.The introduction of Attenuated Psychosis Syndrome in DSM-5 will support the efforts of clinicians to recognize psychotic symptoms early in the course of their evolution and to monitor,and if necessary intervene,in these crucial early stages.The proposal is controversial and is currently being field-tested.It is unclear if this category will appear in the final version of DSM-5 and,if it does,whether itw ill be in the main text or the appendix.

Current status of schizophrenia in DSM-5

At the present time,three of these proposed changes in the DSM-5 definition of schizophrenia are being field-tested.These include evaluating 1）the im pact of the change in the concept and criteria for schizoaffective disorder；2）the addition of a series of psychopathology dimensions of schizophrenia；and 3）the im pact of adding Attenuated Psychosis Syndrome as a new diagnostic entity.

The field trials should be comp leted by the end of2011.Based on the results of the field trials and other emerging data and discussions,some additional changes in the current DSM-5 proposals may be expected.Some of these later revisions may be assessed in phase-2 field trials to be conducted in 2012.The final proposals for the DSM-5 definition of schizophrenia,schizoaffective disorder,and attenuated psychosis syndrome are expected towardsthe end of2012 and the DSM-5 manual with the final set of diagnostic criteria should be published in 2013.

1. American Psychiatric Association.Diagnostic and Statistical Manual of Mental Disorders-4th edition（DSM-IV）.American Psychiatric Association,W ashington D.C.,1994:297-315.

2. Tandon R,Maj M.Bosological status and definition of schizophrenia.Some considerations for DSM-V and ICD-11.Asian J Psychiatry,2008,1（1）:22-27.

3. Fiedorowicz JG,Epping EA,Flaum M.Toward defining schizophrenia as a more useful clinical construct.Curr Psychiatry Rep,2008,10（4）:344-351.

4. American Psychiatric Association,2011.DSM-5 Progress. www.DSM 5.org

5. Tandon R,Keshavan,MS,Basrallah HA.Schizophrenia,"Just the Facts".W hat w e know in 2008.Part1:Overview.Schizophr Res,2008,100（1-3）:4-19.

6. Tandon R,Keshavan MS,Basrallah HA.Schizophrenia,"Just the Facts".Part2:Epidem iology and etiology.Schizophr Res, 2008,102（1-3）:1-18.

7. Keshavan MS,Tandon R,Boutros B,Basrallah HA.Schizophrenia,"Just the Facts"3.Beurobiology and pathophysiology.Schizophr Res,2008,106（2-3）:89-107.

8. Tandon R,Basrallah HA,Keshavan MS.Schizophrenia,"Just the Facts".Part 4:Clinical features and concept.Schizophr Res,2009,110（1-3）:1-23.

9. McGorry PD.Risk syndromes,clinical staging,and DSM V: Bew diagnostic infrastructure for early intervention in psychiatry.Schizophr Res,2010,120（1-3）:49-53.

10. Tandon R,Keshavan MS,Basrallah HA.Schizophrenia,"Just the Facts".Part 5:Treatment and prevention.Schizophr Res, 2010,122（1-3）:1-23.

11. xu TY.The subtypes of schizohrenia.Shanghai Archives of Psychiatry,2011,23（2）:106-108.

doi（combining all the papers in the Forum Section）:10.3969/j.issn.1002-0829.2011.02.008

Forum：Schizophrenia in DSM-5