Presque 20ans après celle du DSM-IV, la publication du DSM-5 est un événement majeur dans le champ de la psychiatrie. Chaque révision du texte du DSM vise à améliorer la fidélité et la validité des diagnostics psychiatriques et améliorer ainsi son utilité clinique. Le DSM-5 s’écarte sur de nombreux points des éditions précédentes, apportant plusieurs changements concernant la schizophrénie : un abandon des formes cliniques de la schizophrénie en faveur d’une évaluation dimensionnelle des signes et des symptômes, une relativisation de l’importance des symptômes de premier rang ainsi qu’une clarification de la définition des symptômes négatifs, une nouvelle spécification de l’évolution, une clarification du statut nosologique de la catatonie, et une définition plus précise du trouble schizo-affectif délimitant ses contours et le séparant de la schizophrénie et des troubles de l’humeur avec caractéristiques psychotiques. Tous les changements ayant concerné la schizophrénie dans le DSM-5 devraient principalement faciliter son évaluation clinique et sa prise en charge thérapeutique, et constitueraient un champ de recherche visant à mieux comprendre sa pathogenèse. Nous proposons de dresser dans ce travail un portrait des principaux changements introduits dans le DSM-5, traitant plus spécifiquement de la schizophrénie et leurs justifications.

The 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) was issued almost 20 years after the previous edition, and it was a major event in the field of psychiatry. This new edition of the DSM aimed to improve the reliability of psychiatric diagnoses, to improve its clinical utility, to address problems identified in DSM-IV, and to incorporate new knowledge and understanding accumulated since the earlier version. The aim of this paper is to describe and comment the changes made from DSM-IV to DSM-5 concerning schizophrenia.

PubMed and Medline search, Scopus, journal and textbook articles have been accessed for the review of literature on DSM-5 changes related to schizophrenia.

Several minor but important changes have been made to the schizophrenia diagnostic criteria in DSM-5. The special treatment of Schneiderian first-rank hallucinations was removed because these symptoms have not been found to be specific for schizophrenia. Likewise, the privileged status of bizarre delusions was removed. Classic subtypes of schizophrenia provide a poor description of the heterogeneity of schizophrenia and had limited diagnostic stability and little clinical utility. As a result, all these subtypes were removed. Dimensional assessment of symptoms was added. It can be used for treatment monitoring and planning and the prediction of course and outcome. This change allowed for more specific and individualized assessment of patients, and better understanding of heterogeneity of schizophrenia. Negative symptoms were clarified. Diminished emotional expression and avolition were considered as the two domains of negative symptoms because they better describe distinguishable aspects of negative symptoms. The DSM-5 has also provided a clearer separation between schizophrenia with mood symptoms and schizoaffective disorder. Schizoaffective disorder was explicitly reconceptualized as a longitudinal and not a cross-sectional diagnosis. The relationship of schizophrenia to catatonia was clarified. Catatonia is treated consistently across the DSM-5 manual as a specifier, and the same criteria to diagnose catatonia are utilized across the manual. A new category of “attenuated psychosis syndrome” was added to section 3 (Appendix) of DSM-5 to describe a condition with recent onset of psychotic symptoms in attenuated forms. Demonstrating adequate reliability of the proposed disorder diagnosis was not possible. Therefore, attenuated psychosis syndrome requires further study.

The etio-pathophysiological nosology of schizophrenia has remained elusive. Changes proposed in the DSM treatment of schizophrenia are relatively modest and the core of the DSM-IV diagnostic criteria is retained. The provision of dimensional assessments with a simple rating scale appears promising and should encourage provision of measurement-based care. These changes should improve characterization of individuals with schizophrenia and facilitate clinical assessment and treatment. In addition, they constitute a research field to better elucidate its nature and understand its pathogenic mechanism.