Time for a Fresh Start? Rethinking Psychosis in DSM-V

It is remarkable that the phenotype of psychosis that is standard throughout the world today originated in mid-19th century psychiatric hospitals with the formulations of Kraepelin. Now, more than 100 years later, this issue of Schizophrenia Bulletin presents a selection of papers reporting the proceedings of a conference titled “Deconstructing Psychosis.” The conference was one in a series titled “The Future of Psychiatric Diagnosis: Refining the Research Agenda,” convened by the American Psychiatric Association (APA) in collaboration with the World Health Organization (WHO) and the US National Institutes of Health (NIH), with funding provided by the NIH. Summary reports from the other conferences can be found at the APA-sponsored Web site www.dsm5.org.

Research Planning for the Diagnostic and Statistical Manual of Mental Disorders/International Classification of Diseases

The APA/WHO/NIH conference series represents a key element in a multiphase research review process designed to set the stage for the fifth revision of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-V). The formal revision process began in 2006, with the appointment of David J. Kupfer, M.D., as Chair of the DSM-V Task Force, and the author (D. A. Regier) as Vice Chair. Both of us have been extensively involved in the research planning process described here and are enthusiastic about translating the results of this effort into the DSM-V.

In its entirety, the research planning process entails 10 workgroups, each focused on a specific diagnostic topic or category, and 2 additional workgroups dedicated to methodological considerations in nosology and classification.

Within the APA, the American Psychiatric Institute for Research and Education (APIRE), under the direction of the author holds lead responsibility for organizing and administering the diagnosis research planning conferences. Members of the Executive Steering Committee for the series include representatives of the WHO's Division of Mental Health and Prevention of Substance Abuse and of 3 NIH institutes that are jointly funding the project: the National Institute of Mental Health (NIMH), the National Institute on Drug Abuse (NIDA), and the National Institute on Alcohol Abuse and Alcoholism (NIAAA).

APA published the Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition (DSM-IV), in 1994¹ and a text revision in 2000.² Although DSM-V is not scheduled to appear until 2012, planning for the fifth revision began in 1999 with a collaboration between APA and NIMH designed to stimulate research that would address key issues in psychiatric nosology. A first product of this joint venture was the preparation of 6 white papers that proposed broad-brush recommendations for research in key areas; topics included developmental issues, gaps in the current classification, disability and impairment, neuroscience, nomenclature, and cross-cultural issues. These white papers were published in A Research Agenda for DSM-V.³ This volume more recently has been followed by a second compilation of white papers that outline mental disorder diagnosis-related research needs in the areas of gender, infants and children, and geriatric populations.⁴

As a second phase of planning, APA in collaboration with colleagues at WHO, developed a proposal for the cooperative research planning conference grant that NIMH awarded to APIRE in 2003, with substantial additional funding support from NIDA and NIAAA. Proceedings of the conferences funded under the grant will serve as resource documents for the DSM-V revision Task Force and disorder-specific workgroups.

The conferences have multiple objectives. One is to promote international collaboration among members of the scientific community with the aim of eliminating the remaining disparities between the DSM-V and the International Classification of Diseases⁵ Mental and Behavioural Disorders section.⁶ A second goal is to stimulate the empirical research necessary to allow informed decision-making regarding deficiencies identified in DSM-IV. A third is to facilitate the development of criteria that researchers worldwide may use in planning and conducting future research exploring the etiology and pathophysiology of mental disorders. Challenging as it is, this last objective reflects widespread agreement in the field that the well-established reliability and clinical utility of prior DSM classifications must be matched in the future by a renewed focus on the validity of diagnoses.

APA attaches high priority to ensuring that information and research recommendations generated by each of the workgroups are readily available to investigators who are concurrently updating other national and international classifications of mental and behavioral disorders. Toward this end, the Executive Steering Committee of the conference grant has made strenuous efforts to enlist the participation of investigators from all parts of the world in the project. Each conference in the series has 2 co-chairs, drawn, respectively, from the United States and a country other than the United States; approximately half of the experts invited to each working conference are from outside the United States, and half of the conferences are being convened outside the United States.

A Broad Focus on Psychosis

The deconstructing psychosis research planning conference was designed, and the participant roster built, with the aim of reviewing an array of disorders in which psychotic phenomena are expressed: schizophrenia, schizoaffective disorder, bipolar disorder, major depressive disorder with psychotic features, and substance-induced psychosis. Logistical considerations precluded our expanding the conference agenda to other important areas, such as “functional” psychotic states seen in paranoia, psychoses associated with the dementias, and neurologic illnesses such as Parkinson's and Huntington's diseases; clearly, however, it will be important in the future to more thoroughly compare the nature of psychotic phenomena, including localization of brain function, across these and other conditions.

These papers from the conference are being published concurrently with the initial work of the DSM-V revision Task Force. The extent to which DSM-V—as well as International Classification of Diseases, 11th Edition (ICD-11)—ultimately embodies ideas and proposals generated at the conference will be a function of decisions to be made over the next several years, decisions that will incorporate into our current understanding of psychosis information gleaned from recent research and investigations now underway. That said, it is timely to describe here the transition from the “planning” phase to the “action” phase of the DSM-V/ICD-11 revisions.

The conference agenda reflected continuing interest in the range of phenomenological manifestations that historically have represented our grasp of psychosis; these include, but are not limited to, disorganized thought, primary negative symptoms, avolition/restricted affect, positive symptoms, and culture-specific manifestations of psychosis. Additional features of psychosis are observed in other disorders. Psychosis associated with major depressive disorder, eg, often is characterized by neuropsychological impairments in areas such as attention, executive function, and verbal declarative memory. Beyond interest in knowledge gained to date, conference participants also looked ahead. During the research review, key issues emerged that cut across multiple diagnostic categories. These include interest in viewing and classifying mental disorders from a developmental perspective, reflecting growing awareness that many conditions evolve over the life course. The notion of “disorder spectra” also drew the attention of several planning workgroups. Accumulating information about putative etiological and pathophysiological mechanisms as well as phenomenological features of different conditions raised questions about more informative approaches “lumping and splitting” disorders in a manner optimally conducive to both clinical utility and future research. Spectra concepts might well also shed light on a necessary distinction between our current notions of comorbidity as opposed to a possible moderator effect of a given condition on another. Among spectra considered during the review were those of psychotic phenomena associated with several disorders, obsessive-compulsive behaviors that may be common to multiple discrete diagnoses in the current classification, a new grouping of so-called stress and fear circuitry disorders that promise to reveal common neurobiological substrates, and the stew of generalized anxiety and major depressive disorders, to name a few. A third cross-cutting issue concerns the somatic, or somatoform, features of mental illness, signaling widespread recognition that the brain is an organ much like—albeit at a greater level of complexity—other bodily organs; our understanding of mental disorders cannot be separated from broader health and medical concerns. Finally, and in large part, due to the emphasis that the research review has placed on the demographic diversity and international representation of participants, attention to the influence of gender and culture on mental disorder has been prominent in our consideration of future mental disorder classifications.

Cutting across all these superordinate topics is a mounting sense of the timeliness of incorporating dimensional approaches into our current categorical systems of diagnosis and classification. Long a topic of interest in the Axis II category of personality disorders, the question of dimensional approaches now has permeated thinking of traditional Axis I disorders. Indeed, the relevance of dimensional approaches to all mental disorder diagnoses and to promising endophenotypes of disorders prompted the addition of a workgroup/conference to focus on how dimensional constructs might be added to the classification in its entirety. Papers from that conference will be published in July 2007 in the International Journal of Methods in Psychiatric Research and, like these papers on psychosis, will be available in an APA monograph in the near future.

As the formal DSM revision ramps up in 2007, the Task Force that will coordinate the work of an envisioned dozen-plus, diagnosis-specific workgroups is preparing working papers focused on these 4 topics with the intent of setting a conceptual framework for the revision before the workgroups become too deeply invested in a process of fine-tuning existing diagnoses.

We intend that the DSM workgroups responsible for the array of disorders that subsume psychotic illness will carry forward the open-minded thinking that characterized the research review process to more fully evaluate any need or potential benefits of proposing changes in definitions, boundaries, or linkages among psychotic disorders and with other diagnostic domains in the DSM-V.

It is clear that in the 21st century, the nosology of mental disorders will remain a moving target. With appreciation of the pace of progress in multiple areas, ranging from molecular genetics to brain imaging to social, behavioral, and clinical science, we intend for the DSM-V to be a “living document” that will explicitly be able to accommodate new research findings as they are replicated and are shown to better define and validate our diagnostic entities. That this will require a platform with greater flexibility than the one we currently use implies the urgent need to fully explore and take advantage of the similarly fast-evolving potential for electronic publishing and, in turn, continuous revisions of psychiatric classification systems in the decades ahead.