Predicting and preventing bipolar disorder: the need to fundamentally advance the strategic approach

The clinical characterization of the adult patient with bipolar disorder aimed at personalization of management

Bipolar disorder is heterogeneous in phenomenology, illness trajectory, and response to treatment. Despite evidence for the efficacy of multimodal-ity interventions, the majority of persons affected by this disorder do not achieve and sustain full syndromal recovery. It is eagerly anticipated that combining datasets across various information sources (e.g., hierarchical "multi-omic" measures, electronic health records), analyzed using advanced computational methods (e.g., machine learning), will inform future diagnosis and treatment selection. In the interim, identifying clinically meaningful subgroups of persons with the disorder having differential response to specific treatments at point-of-care is an empirical priority. This paper endeavours to synthesize salient domains in the clinical characterization of the adult patient with bipolar disorder, with the overarching aim to improve health outcomes by informing patient management and treatment considerations. Extant data indicate that characterizing select domains in bipolar disorder provides actionable information and guides shared decision making. For example, it is robustly established that the presence of mixed features - especially during depressive episodes - and of physical and psychiatric comorbidities informs illness trajectory, response to treatment, and suicide risk. In addition, early environmental exposures (e.g., sexual and physical abuse, emotional neglect) are highly associated with more complicated illness presentations, inviting the need for developmentally-oriented and integrated treatment approaches. There have been significant advances in validating subtypes of bipolar disorder (e.g., bipolar I vs. II disorder), particularly in regard to pharmacological interventions. As with other severe mental disorders, social functioning, interpersonal/family relationships and internalized stigma are domains highly relevant to relapse risk, health outcomes, and quality of life. The elevated standardized mortality ratio for completed suicide and suicidal behaviour in bipolar disorder invites the need for characterization of this domain in all patients. The framework of this paper is to describe all the above salient domains, providing a synthesis of extant literature and recommendations for decision support tools and clinical metrics that can be implemented at point-of-care.

Evaluating cognitive function in unaffected relatives of individuals with bipolar disorders: A meta-analysis

BACKGROUND

Available studies have evaluated cognition in the unaffected relatives of bipolar disorder patients; however, to our knowledge, there has been no quantitative analysis evaluating the foregoing association. Herein, this meta-analysis aims to provide a quantitative synthesis of the extant literature reporting on the association between performance in cognitive domains (i.e., executive function, attention, learning and memory or global cognition) amongst unaffected individuals of probands with bipolar disorders.

METHODS

Online databases (i.e., PubMed, PsycINFO) and Google Scholar were searched from inception to 20 September 2021. Studies with unaffected, first-degree relatives of individuals with DSM-IV or DSM-5 defined bipolar disorders were included. The risk of bias was assessed using the ROBINS-1 tool, and the quality of the sources was evaluated using GRADE criteria. The results of the studies were quantitatively synthesized using Cohen's d effect sizes via a random-effects meta-analytic approach on JASP.

RESULTS

A total of 15 studies were included in the final review. Overall, results indicate that cognitive performance across all domains is moderately impaired in unaffected relatives of individuals with bipolar disorders (d = 0.488). Sub-analysis suggests there is a higher level of impairment in executive functioning (d = 0.612).

DISCUSSION

The identification of cognitive deficits in unaffected relatives of probands with bipolar disorders indicates that cognitive impairment is endophenotypic and a core disturbance in persons with bipolar disorders; future studies should endeavour to target cognition as a potential pre-emptive and prevention strategy of bipolar disorders.

Bipolar disorders

Bipolar disorders are a complex group of severe and chronic disorders that includes bipolar I disorder, defined by the presence of a syndromal, manic episode, and bipolar II disorder, defined by the presence of a syndromal, hypomanic episode and a major depressive episode. Bipolar disorders substantially reduce psychosocial functioning and are associated with a loss of approximately 10-20 potential years of life. The mortality gap between populations with bipolar disorders and the general population is principally a result of excess deaths from cardiovascular disease and suicide. Bipolar disorder has a high heritability (approximately 70%). Bipolar disorders share genetic risk alleles with other mental and medical disorders. Bipolar I has a closer genetic association with schizophrenia relative to bipolar II, which has a closer genetic association with major depressive disorder. Although the pathogenesis of bipolar disorders is unknown, implicated processes include disturbances in neuronal-glial plasticity, monoaminergic signalling, inflammatory homoeostasis, cellular metabolic pathways, and mitochondrial function. The high prevalence of childhood maltreatment in people with bipolar disorders and the association between childhood maltreatment and a more complex presentation of bipolar disorder (eg, one including suicidality) highlight the role of adverse environmental exposures on the presentation of bipolar disorders. Although mania defines bipolar I disorder, depressive episodes and symptoms dominate the longitudinal course of, and disproportionately account for morbidity and mortality in, bipolar disorders. Lithium is the gold standard mood-stabilising agent for the treatment of people with bipolar disorders, and has antimanic, antidepressant, and anti-suicide effects. Although antipsychotics are effective in treating mania, few antipsychotics have proven to be effective in bipolar depression. Divalproex and carbamazepine are effective in the treatment of acute mania and lamotrigine is effective at treating and preventing bipolar depression. Antidepressants are widely prescribed for bipolar disorders despite a paucity of compelling evidence for their short-term or long-term efficacy. Moreover, antidepressant prescription in bipolar disorder is associated, in many cases, with mood destabilisation, especially during maintenance treatment. Unfortunately, effective pharmacological treatments for bipolar disorders are not universally available, particularly in low-income and middle-income countries. Targeting medical and psychiatric comorbidity, integrating adjunctive psychosocial treatments, and involving caregivers have been shown to improve health outcomes for people with bipolar disorders. The aim of this Seminar, which is intended mainly for primary care physicians, is to provide an overview of diagnostic, pathogenetic, and treatment considerations in bipolar disorders. Towards the foregoing aim, we review and synthesise evidence on the epidemiology, mechanisms, screening, and treatment of bipolar disorders.

Demographic and Clinical Characteristics, Including Subsyndromal Symptoms Across Bipolar-Spectrum Disorders in Adolescents

Objectives: Bipolar disorder (BD) is a debilitating illness that often starts at an early age. Prevention of first and subsequent mood episodes, which are usually preceded by a period characterized by subthreshold symptoms is important. We compared demographic and clinical characteristics including severity and duration of subsyndromal symptoms across adolescents with three different bipolar-spectrum disorders. Methods: Syndromal and subsyndromal psychopathology were assessed in adolescent inpatients (age = 12-18 years) with a clinical mood disorder diagnosis. Assessments included the validated Bipolar Prodrome Symptom Interview and Scale-Prospective (BPSS-P). We compared phenomenology across patients with a research consensus conference-confirmed DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) diagnoses of BD-I, BD-not otherwise specified (NOS), or mood disorder (MD) NOS. Results: Seventy-six adolescents (age = 15.6 ± 1.4 years, females = 59.2%) were included (BD-I = 24; BD-NOS = 29; MD-NOS = 23) in this study. Median baseline global assessment of functioning scale score was 21 (interquartile range = 17-40; between-group p = 0.31). Comorbidity was frequent, and similar across groups, including disruptive behavior disorders (55.5%, p = 0.27), anxiety disorders (40.8%, p = 0.98), and personality disorder traits (25.0%, p = 0.21). Mania symptoms (most frequent: irritability = 93.4%, p = 0.82) and depressive symptoms (most frequent: depressed mood = 81.6%, p = 0.14) were common in all three BD-spectrum groups. Manic and depressive symptoms were more severe in both BD-I and BD-NOS versus MD-NOS (p < 0.0001). Median duration of subthreshold manic symptoms was shorter in MD-NOS versus BD-NOS (11.7 vs. 20.4 weeks, p = 0.002) and substantial in both groups. The most used psychotropics upon discharge were antipsychotics (65.8%; BD-I = 79.2%; BD-NOS = 62.1%; MD-NOS = 56.5%, p = 0.227), followed by mood stabilizers (43.4%; BD-I = 66.7%; BD-NOS = 31.0%; MD-NOS = 34.8%, p = 0.02) and antidepressants (19.7%; BD-I = 20.8%; BD-NOS = 10.3%; MD-NOS = 30.4%). Conclusions: Youth with BD-I, BD-NOS, and MD-NOS experience considerable symptomatology and are functionally impaired, with few differences observed in psychiatric comorbidity and clinical severity. Moreover, youth with BD-NOS and MD-NOS undergo a period with subthreshold manic symptoms, enabling identification and, possibly, preventive intervention of those at risk for developing BD or other affective episodes requiring hospitalization.

The Bipolar Illness Onset study: research protocol for the BIO cohort study

INTRODUCTION

Bipolar disorder is an often disabling mental illness with a lifetime prevalence of 1%-2%, a high risk of recurrence of manic and depressive episodes, a lifelong elevated risk of suicide and a substantial heritability. The course of illness is frequently characterised by progressive shortening of interepisode intervals with each recurrence and increasing cognitive dysfunction in a subset of individuals with this condition. Clinically, diagnostic boundaries between bipolar disorder and other psychiatric disorders such as unipolar depression are unclear although pharmacological and psychological treatment strategies differ substantially. Patients with bipolar disorder are often misdiagnosed and the mean delay between onset and diagnosis is 5-10 years. Although the risk of relapse of depression and mania is high it is for most patients impossible to predict and consequently prevent upcoming episodes in an individual tailored way. The identification of objective biomarkers can both inform bipolar disorder diagnosis and provide biological targets for the development of new and personalised treatments. Accurate diagnosis of bipolar disorder in its early stages could help prevent the long-term detrimental effects of the illness.The present Bipolar Illness Onset study aims to identify (1) a composite blood-based biomarker, (2) a composite electronic smartphone-based biomarker and (3) a neurocognitive and neuroimaging-based signature for bipolar disorder.

METHODS AND ANALYSIS

The study will include 300 patients with newly diagnosed/first-episode bipolar disorder, 200 of their healthy siblings or offspring and 100 healthy individuals without a family history of affective disorder. All participants will be followed longitudinally with repeated blood samples and other biological tissues, self-monitored and automatically generated smartphone data, neuropsychological tests and a subset of the cohort with neuroimaging during a 5 to 10-year study period.

ETHICS AND DISSEMINATION

The study has been approved by the Local Ethical Committee (H-7-2014-007) and the data agency, Capital Region of Copenhagen (RHP-2015-023), and the findings will be widely disseminated at international conferences and meetings including conferences for the International Society for Bipolar Disorders and the World Federation of Societies for Biological Psychiatry and in scientific peer-reviewed papers.

TRIAL REGISTRATION NUMBER

NCT02888262.

Refractory bipolar disorder and neuroprogression

Immune activation and failure of physiologic compensatory mechanisms over time have been implicated in the pathophysiology of illness progression in bipolar disorder. Recent evidence suggests that such changes are important contributors to neuroprogression and may mediate the cross-sensitization of episode recurrence, trauma exposure and substance use. The present review aims to discuss the potential factors related to bipolar disorder refractoriness and neuroprogression. In addition, we will discuss the possible impacts of early therapeutic interventions as well as the alternative approaches in late stages of the disorder.