Preserving the clinician-researcher interface in the age of RDoC: the continuing need for DSM-5/ICD-11 characterization of study populations

The relevance of 'mixed anxiety and depression' as a diagnostic category in clinical practice

According to ICD-10 criteria, mixed anxiety and depressive disorder (MADD) is characterized by co-occurring, subsyndromal symptoms of anxiety and depression, severe enough to justify a psychiatric diagnosis, but neither of which are clearly predominant. MADD appears to be very common, particularly in primary care, although prevalence estimates vary, often depending on the diagnostic criteria applied. It has been associated with similarly pronounced distress, impairment of daily living skills, and reduced health-related quality of life as fully syndromal depression and anxiety. Although about half of the patients affected remit within a year, non-remitting patients are at a high risk of transition to a fully syndromal psychiatric disorder. The validity and clinical usefulness of MADD as a diagnostic category are under debate. It has not been included in the recently released DSM-5 since the proposed diagnostic criteria turned out to be not sufficiently reliable. Moreover, reviewers have disputed the justification of MADD based on divergent results regarding its prevalence and course, diagnostic stability over time, and nosological inconsistencies between subthreshold and threshold presentations of anxiety and depressive disorders. We review the evidence in favor and against MADD and argue that it should be included into classification systems as a diagnostic category because it may enable patients to gain access to appropriate treatment early. This may help to reduce patients' distress, prevent exacerbation to a more serious psychiatric disorder, and ultimately reduce the societal costs of this very common condition.

Bias in emerging biomarkers for bipolar disorder

BACKGROUND

To date no comprehensive evaluation has appraised the likelihood of bias or the strength of the evidence of peripheral biomarkers for bipolar disorder (BD). Here we performed an umbrella review of meta-analyses of peripheral non-genetic biomarkers for BD.

METHOD

The Pubmed/Medline, EMBASE and PsycInfo electronic databases were searched up to May 2015. Two independent authors conducted searches, examined references for eligibility, and extracted data. Meta-analyses in any language examining peripheral non-genetic biomarkers in participants with BD (across different mood states) compared to unaffected controls were included.

RESULTS

Six references, which examined 13 biomarkers across 20 meta-analyses (5474 BD cases and 4823 healthy controls) met inclusion criteria. Evidence for excess of significance bias (i.e. bias favoring publication of 'positive' nominally significant results) was observed in 11 meta-analyses. Heterogeneity was high for (I 2 ⩾ 50%) 16 meta-analyses. Only two biomarkers met criteria for suggestive evidence namely the soluble IL-2 receptor and morning cortisol. The median power of included studies, using the effect size of the largest dataset as the plausible true effect size of each meta-analysis, was 15.3%.

CONCLUSIONS

Our findings suggest that there is an excess of statistically significant results in the literature of peripheral biomarkers for BD. Selective publication of 'positive' results and selective reporting of outcomes are possible mechanisms.

The National Institute of Mental Health Research Domain Criteria: A Bridge Too Far

The National Institute of Mental Health is actively promoting Research Domain Criteria as a new model for the research on mental disorders. Research Domain Criteria approaches disorders through a matrix, linking units of analysis with domains, based on the assumption that psychopathology reflects abnormal connectivity in the brain. This review suggests that the Research Domain Criteria perspective is likely to fail to provide an adequate basis for clinical psychiatric theory and practice. First, it uses models from neuroscience that are insufficiently developed. Second, it is based on the premise that mental phenomena and mental disorders can be reduced to neural activity, without consideration of cognition, experience, and social interaction. Third, it downplays psychosocial factors in psychopathology and treatment. Research Domain Criteria may therefore prove inadequate for providing a neuroscientific basis for psychiatric nosology and treatment and needs to be supplemented with a broader view that incorporates insights from social sciences, psychology, and phenomenology.

Design challenges in transdiagnostic psychotherapy research: Comparing Transdiagnostic Behavior Therapy (TBT) to existing evidence-based psychotherapy in veterans with affective disorders

BACKGROUND

To address the limitations of disorder-specific approaches, newer transdiagnostic approaches to psychotherapy have been developed to provide a single treatment that is capable of addressing several, related disorders. However, the recruitment of multiple diagnoses presents many challenges to the traditional design of psychotherapy randomized controlled trials (RCTs).

OBJECTIVE

The goal of the manuscript is to present the challenges and rationale for designing a RCT for transdiagnostic treatment to inform and aid in the development of future investigations.

METHODS

A recently funded and ongoing RCT for Transdiagnostic Behavior Therapy (TBT) is used as an example to discuss the related design challenges. The TBT study involves the recruitment of 96 veteran participants with any of the following eight principal diagnoses: posttraumatic stress disorder, panic disorder, social anxiety disorder, obsessive compulsive disorder, generalized anxiety disorder, specific phobia, major depressive disorder, or persistent depressive disorder. Within the TBT study, participants will complete a semi-structured diagnostic interview and a series of transdiagnostic self-report measures to determine eligibility and assess baseline symptomatology. Qualifying participants will be randomized to TBT or control psychotherapy. Additional assessments will be completed at post-treatment and 6-month follow-up.

CONCLUSIONS

Due to the transdiagnostic nature of the sample, adjustments to the recruitment and randomization procedures, selection of measures, selection of control psychotherapy, and analysis plan were required. These adjustments have implications to future trials on transdiagnostic psychotherapy protocols as well as future research in line with the transdiagnostic focus of the National Institute of Mental Health's Research Domain Criteria (RDoC) funding strategy.

Implications of RDoC for the research and practice of psychotherapy

The field of psychotherapy is at an important juncture. Recent changes in the field include (a) the skeptical reception of the fifth edition of the Diagnostic and Statistical Manual and (b) NIMH's prioritization of an alternative classification system to guide translational and intervention research. Moreover, (c) the field continues to be held accountable to governmental agencies and third-party payers to demonstrate its empirical basis. Thus, psychological research as it relates to the practice of psychotherapy is at a crossroads. In this article, we provide a brief overview of several generations of psychotherapy outcome research, including the consequences that followed in the 1980s as psychotherapy research moved toward randomized controlled trials for clinical disorders. We delineate the inherent strengths and limitations of this movement and address how the NIMH has recently responded with the Research Domain Criteria (RDoC). We then address philosophical and practical implications of the emphasis on a neuroscientific conceptualization of psychological problems. Finally, we discuss opportunities for a next generation of convergent science that incorporates, rather than replaces, psychosocial variables across stages of translational research and treatment development.

DSM-5 reviewed from different angles: goal attainment, rationality, use of evidence, consequences--part 1: general aspects and paradigmatic discussion of depressive disorders

DSM-5 was published in 2013 after about 10 years of preparation. Part 1 of this paper discusses several more general aspects of DSM-5 and offers a detailed, paradigmatic analysis of changes made to the chapter on depressive disorders. The background for the changes is analysed on the basis of a PubMed search and review papers on the classification of mental disorders in general and on empirical knowledge about individual disorders. Contrary to the original plans, DSM-5 has not introduced a primarily dimensional diagnostic system but has widely preserved the categorical system of disorders. Also, it has not adopted a more neurobiological approach to disorders by including biological markers to increase the objectivity of psychiatric diagnoses but has maintained the primarily symptom-based, descriptive approach. The criteria for some disorders have been changed, including affective, schizophrenic and addiction disorders, and a few new disorders have been added. A minimal version of the dimensional approach was realised through the introduction of several transnosological specifiers and the option to make symptom- or syndrome-related severity and dimensional assessments. These specifiers and assessments might allow a more individualised description of a patient's psychopathological state and more personalised treatment. However, most of the symptom- and syndrome-related assessments are not mandatory and therefore may not be used in clinical practice.