Bipolar II Disorder Is NOT a Myth

Phenotypic clustering of bipolar disorder supports stratification by lithium responsiveness over diagnostic subtypes

INTRODUCTION

The aim of this study was to determine whether the clinical profiles of bipolar disorder (BD) patients could be differentiated more clearly using the existing classification by diagnostic subtype or by lithium treatment responsiveness.

METHODS

We included adult patients with BD-I or II (N = 477 across four sites) who were treated with lithium as their principal mood stabilizer for at least 1 year. Treatment responsiveness was defined using the dichotomized Alda score. We performed hierarchical clustering on phenotypes defined by 40 features, covering demographics, clinical course, family history, suicide behaviour, and comorbid conditions. We then measured the amount of information that inferred clusters carried about (A) BD subtype and (B) lithium responsiveness using adjusted mutual information (AMI) scores. Detailed phenotypic profiles across clusters were then evaluated with univariate comparisons.

RESULTS

Two clusters were identified (n = 56 and n = 421), which captured significantly more information about lithium responsiveness (AMI range: 0.033 to 0.133) than BD subtype (AMI: 0.004 to 0.011). The smaller cluster had disproportionately more lithium responders (n = 47 [83.8%]) when compared to the larger cluster (103 [24.4%]; p = 0.006).

CONCLUSIONS

Phenotypes derived from detailed clinical data may carry more information about lithium responsiveness than the current classification of diagnostic subtype. These findings support lithium responsiveness as a valid approach to stratification in clinical samples.

Clinical distinctions in symptomatology and psychiatric comorbidities between misdiagnosed bipolar I and bipolar II disorder versus major depressive disorder

BACKGROUND

To explore the demographic and clinical features of current depressive episode that discriminate patients diagnosed with major depressive disorder (MDD) from those with bipolar I (BP-I) and bipolar II (BP-II) disorder who were misdiagnosed as having MDD .

METHODS

The Mini-International Neuropsychiatric Interview (MINI) assessment was performed to establish DSM-IV diagnoses of MDD, and BP-I and BP-II, previously being misdiagnosed as MDD. Demographics, depressive symptoms and psychiatric comorbidities were compared between 1463 patients with BP-I, BP-II and MDD from 8 psychiatric settings in mainland China. A multinomial logistic regression model was performed to assess clinical correlates of diagnoses.

RESULTS

A total of 14.5% of the enrolled patients initially diagnosed with MDD were eventually diagnosed with BP. Broad illness characteristics including younger age, higher prevalence of recurrence, concurrent dysthymia, suicidal attempts, agitation, psychotic features and psychiatric comorbidities, as well as lower prevalence of insomnia, weight loss and somatic symptoms were featured by patients with BP-I and/or BP-I, compared to those with MDD. Comparisons between BP-I and BP-II versus MDD indicated distinct symptom profiles and comorbidity patterns with more differences being observed between BP-II and MDD, than between BP-I and MDD .

CONCLUSION

The results provide evidence of clinically distinguishing characteristics between misdiagnosed BP-I and BP- II versus MDD. The findings have implications for guiding more accurate diagnoses of bipolar disorders.

Network dysfunction of sadness facial expression processing and morphometry in euthymic bipolar disorder

Facial emotion recognition (FER), including sadness, is altered in bipolar disorder (BD). However, the relationship between this impairment and the brain structure in BD is relatively unexplored. Furthermore, its association with clinical variables and with the subtypes of BD remains to be clarified. Twenty euthymic patients with BD type I (BD-I), 28 BD type II (BD-II), and 45 healthy controls completed a FER test and a 3D-T1-weighted magnetic resonance imaging. Gray matter volume (GMV) of the cortico-limbic regions implicated in emotional processing was estimated and their relationship with FER performance was investigated using network analysis. Patients with BD-I had worse total and sadness-related FER performance relative to the other groups. Total FER performance was significantly negatively associated with illness duration and positively associated with global functioning in patients with BD-I. Sadness-related FER performance was also significantly negatively associated with the number of previous manic episodes. Network analysis showed a reduced association of the GMV of the frontal-insular-occipital areas in patients with BD-I, with a greater edge strength between sadness-related FER performance and amygdala GMV relative to controls. Our results suggest that FER performance, particularly for facial sadness, may be distinctively impaired in patients with BD-I. The pattern of reduced interrelationship in the frontal-insular-occipital regions and a stronger positive relationship between facial sadness recognition and the amygdala GMV in BD may reflect altered cortical modulation of limbic structures that ultimately predisposes to emotional dysregulation. Future longitudinal studies investigating the effect of mood state on FER performance in BD are warranted.

Bipolar disorder in the International Classification of Diseases-Eleventh version: A review of the changes, their basis, and usefulness

The World Health Organization’s 11^th revision of the International Classification of Diseases (ICD-11) including the chapter on mental disorders has come into effect this year. This review focuses on the “Bipolar or Related Disorders” section of the ICD-11 draft. It describes the benchmarks for the new version, particularly the foremost principle of clinical utility. The alterations made to the diagnosis of bipolar disorder (BD) are evaluated on their scientific basis and clinical utility. The change in the diagnostic requirements for manic and hypomanic episodes has been much debated. Whether the current criteria have achieved an optimum balance between sensitivity and specificity is still not clear. The ICD-11 definition of depressive episodes is substantially different, but the lack of empirical support for the changes has meant that the reliability and utility of bipolar depression are relatively low. Unlike the Diagnostic and Statistical Manual of Mental Disorders, 5^th edition (DSM-5), the ICD-11 has retained the category of mixed episodes. Although the concept of mixed episodes in the ICD-11 is not perfect, it appears to be more inclusive than the DSM-5 approach. Additionally, there are some uncertainties about the guidelines for the subtypes of BD and cyclothymic disorder. The initial results on the reliability and clinical utility of BD are promising, but the newly created diagnostic categories also appear to have some limitations. Although further improvement and research are needed, the focus should now be on facing the challenges of implementation, dissemination, and education and training in the use of these guidelines.

Thing one and thing two1: What 'Doctors use' to doctor you?

This perspective piece is a detailed analysis of the critique by Gordon Parker of the mood disorders clinical practice guidelines (MDcpg²⁰²⁰), in which he claims that bipolar II disorder has been 'banished' despite its formal status in current taxonomies. In this article, I defend the reasoning used by the Committee to adopt a dimensional model for describing and managing mood disorders, in particular bipolar disorder. I also robustly contend the many erroneous inferences made by him in his Viewpoint regarding management recommendations within the MDcpg²⁰²⁰ and demonstrate that there is no valid justification for subtyping bipolar disorder - especially in the manner proposed by the Diagnostic and Statistical Manual of Mental Disorders, 5th edition. Thus, I argue that it was appropriate for the MDcpg²⁰²⁰ Committee to pursue an alternative model to the usual subtyping of bipolar disorder into 'thing one' and 'thing two' and conclude that the now clearly redundant model of Bipolar II should be altogether removed from our lexicon and clinical practice. Indeed, it is time to develop new and alternative models for defining bipolar disorder and among these a dimensional model should be given consideration.

The 2020 Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for mood disorders

OBJECTIVES

To provide advice and guidance regarding the management of mood disorders, derived from scientific evidence and supplemented by expert clinical consensus to formulate s that maximise clinical utility.

METHODS

Articles and information sourced from search engines including PubMed, EMBASE, MEDLINE, PsycINFO and Google Scholar were supplemented by literature known to the mood disorders committee (e.g. books, book chapters and government reports) and from published depression and bipolar disorder guidelines. Relevant information was appraised and discussed in detail by members of the mood disorders committee, with a view to formulating and developing consensus-based recommendations and clinical guidance. The guidelines were subjected to rigorous consultation and external review involving: expert and clinical advisors, key stakeholders, professional bodies and specialist groups with interest in mood disorders.

RESULTS

The Royal Australian and New Zealand College of Psychiatrists mood disorders clinical practice guidelines 2020 (MDcpg²⁰²⁰) provide up-to-date guidance regarding the management of mood disorders that is informed by evidence and clinical experience. The guideline is intended for clinical use by psychiatrists, psychologists, primary care physicians and others with an interest in mental health care.

CONCLUSION

The MDcpg²⁰²⁰ builds on the previous 2015 guidelines and maintains its joint focus on both depressive and bipolar disorders. It provides up-to-date recommendations and guidance within an evidence-based framework, supplemented by expert clinical consensus.

MOOD DISORDERS COMMITTEE

Gin S Malhi (Chair), Erica Bell, Darryl Bassett, Philip Boyce, Richard Bryant, Philip Hazell, Malcolm Hopwood, Bill Lyndon, Roger Mulder, Richard Porter, Ajeet B Singh and Greg Murray.

The 2020 Royal Australian and New Zealand College of psychiatrists clinical practice guidelines for mood disorders: Bipolar disorder summary

OBJECTIVES

To provide a succinct, clinically useful summary of the management of bipolar disorder, based on the 2020 Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for mood disorders (MDcpg²⁰²⁰ ).

METHODS

To develop the MDcpg²⁰²⁰ , the mood disorders committee conducted an extensive review of the available literature to develop evidence-based recommendations (EBR) based on National Health and Medical Research Council (NHMRC) guidelines. In the MDcpg²⁰²⁰ , these recommendations sit alongside consensus-based recommendations (CBR) that were derived from extensive deliberations of the mood disorders committee, drawing on their expertise and clinical experience. This guideline summary is an abridged version that focuses on bipolar disorder. In collaboration with international experts in the field, it synthesises the key recommendations made in relation to the diagnosis and management of bipolar disorder.

RESULTS

The bipolar disorder summary provides a systematic approach to diagnosis, and a logical clinical framework for management. It addresses the acute phases of bipolar disorder (mania, depression and mixed states) and its longer-term management (maintenance and prophylaxis). For each phase it begins with Actions, which include important strategies that should be implemented from the outset wherever possible. These include for example, lifestyle changes, psychoeducation and psychological interventions. In each phase, the summary advocates the use of Choice medications for pharmacotherapy, which are then used in combinations along with additional Alternatives to manage acute symptoms or maintain mood stability and provide prophylaxis. The summary also recommends the use of electroconvulsive therapy (ECT) for each of the acute phases but not for maintenance therapy. Finally, it briefly considers bipolar disorder in children and its overlap in adults with borderline personality disorder.

CONCLUSIONS

The bipolar disorder summary provides up to date guidance regarding the management of bipolar disorder, as set out in the MDcpg²⁰²⁰ . The recommendations are informed by evidence and clinical expertise and experience. The summary is intended for use by psychiatrists, psychologists and primary care physicians but will be of interest to anyone involved in the management of patients with bipolar disorder.

The existential crisis of bipolar II disorder

The issue of categorical vs. dimensional classification of bipolar disorder continues to generate controversy as it has for generations. Despite the evidence that no psychiatric disorder has discrete boundaries separating pathological and nonpathological states, and within a disorder, no clear differences separate subtypes-which would suggest a more dimensional approach-there are valid reasons to continue with our current categorical system, which distinguishes bipolar I from bipolar II disorder. Complicating the issue, a number of interested constituencies, including patients and their families, clinicians, scientists/researchers, and governmental agencies and insurance companies have different interests and needs in this controversy. This paper reviews both the advantages and disadvantages of continuing the bipolar I/bipolar II split vs. redefining bipolar disorder as one unified diagnosis. Even with one unified diagnosis, other aspects of psychopathology can be used to further describe and classify the disorder. These include both predominant polarity and categorizing symptoms by ACE-activity, cognition and energy. As a field, we must decide whether changing our current classification before we have a defining biology and genetic profile of bipolar disorder is worth the disruption in our current diagnostic system.

Threading a pathway through the forest of mood and personality disorders

The classification of mood and personality disorders has become unnecessarily complicated. It has become bogged down by well-meaning but unhelpful subcategories that puzzle the will of clinicians to make useful judgements. The answer is to think of bipolar, depressive and personality disorders as each constituting a spectrum of severity and not to be too preoccupied with individual labels. It would also be useful to avoid the diagnostic chimera of borderline personality disorder, a condition that defies proper classification.