The Emergent Course of Bipolar Disorder: Observations Over Two Decades From the Canadian High-Risk Offspring Cohort

Clinical and neurostructural characteristics among youth with familial and non-familial bipolar disorder: Family history and youth bipolar disorder

BACKGROUND

Bipolar disorder (BD) is highly heritable and often severe, particularly when illness onset occurs early in life. There is limited knowledge regarding the clinical and neurostructural correlates of family history of BD among youth with BD.

METHODS

Clinical characteristics were evaluated in 197 youth with BD, ages 13-20 years, including 87 with familial BD and 110 with non-familial BD. Structural neuroimaging was examined in a subsample of familial BD (n=39), non-familial BD (n=42), and healthy control (HC, n=58) youth. Region of interest (ROI) analyses of anterior cingulate cortex (ACC), inferior frontal gyrus (IFG), and amygdala were complemented by whole-brain vertex-wise analyses.

RESULTS

Youth with familial BD had more family history of other psychiatric disorders, less severe worst manic episode, and less treatment with lithium, selective serotonin reuptake inhibitor (SSRI) antidepressants, and any lifetime psychiatric medications. None of these findings survived after correction for multiple comparisons. There were no significant between-group differences in ROI analyses. In whole-brain analyses, significant differences in cortical thickness were as follows: familial and non-familial BD < HC in left precentral gyrus and right inferior parietal lobe; familial BD < HC in left superior frontal gyrus; non-familial BD < HC in right precentral gyrus.

LIMITATIONS

Relatives did not complete full diagnostic interviews.

CONCLUSIONS

There were relatively few differences in clinical and neurostructural correlates related to family history of BD in youth with BD. Current findings suggest that family history of BD is not a strong contributor to the clinical or neuroimaging phenotypes in youth with BD.

Mitochondrial dysfunction as a critical event in the pathophysiology of bipolar disorder

The understanding of the pathophysiology of bipolar disorder (BD) remains modest, despite recent advances in neurobiological research. The mitochondrial dysfunction hypothesis of bipolar disorder has been corroborated by several studies involving postmortem brain analysis, neuroimaging, and specific biomarkers in both rodent models and humans. Evidence suggests that BD might be related to abnormal mitochondrial morphology and dynamics, neuroimmune dysfunction, and atypical mitochondrial metabolism and oxidative stress pathways. Mitochondrial dysfunction in mood disorders is also associated with abnormal Ca2+ levels, glutamate excitotoxicity, an imbalance between pro- and antiapoptotic proteins towards apoptosis, abnormal gene expression of electron transport chain complexes, and decreased ATP synthesis. This paper aims to review and discuss the implications of mitochondrial dysfunction in BD etiology and to explore mitochondria as a potential target for novel therapeutic agents.

Comorbidity of ADHD and adult bipolar disorder: A systematic review and meta-analysis

Attention-deficit / hyperactivity disorder (ADHD) and Bipolar Disorder (BD) are common mental disorders with a high degree of comorbidity. However, no systematic review with meta-analysis has aimed to quantify the degree of comorbidity between both disorders. To this end we performed a systematic search of the literature in October 2020. In a meta-analysis of 71 studies with 646,766 participants from 18 countries, it was found that about one in thirteen adults with ADHD was also diagnosed with BD (7.95 %; 95 % CI: 5.31-11.06), and nearly one in six adults with BD had ADHD (17.11 %; 95 % CI: 13.05-21.59 %). Substantial heterogeneity of comorbidity rates was present, highlighting the importance of contextual factors: Heterogeneity could partially be explained by diagnostic system, sample size and geographical location. Age of BD onset occurred earlier in patients with comorbid ADHD (3.96 years; 95 % CI: 2.65-5.26, p < 0.001). Cultural and methodological differences deserve attention for evaluating diagnostic criteria and clinicians should be aware of the high comorbidity rates to prevent misdiagnosis and provide optimal care for both disorders.

Sleep disturbances and first onset of major mental disorders in adolescence and early adulthood: A systematic review and meta-analysis

Despite several high-quality reviews of insomnia and incidence of mental disorders, prospective longitudinal relationships between a wider range of sleep disturbances and first onset of a depressive, bipolar, or psychotic disorders during the peak age range for onset of these conditions has not been addressed. Database searches were undertaken to identify publications on insomnia, but also on other sleep problems such as hypersomnia, short sleep duration, self-identified and/or generic 'sleep problems' and circadian sleep-wake cycle dysrhythmias. We discovered 36 studies that were eligible for systematic review and from these publications, we identified 25 unique datasets that were suitable for meta-analysis (Number>45,000; age ∼17). Individuals with a history of any type of sleep disturbance (however defined) had an increased odds of developing a mood or psychotic disorder in adolescence or early adulthood (Odds ratio [OR]:1.88; 95% Confidence Intervals:1.67, 2.25) with similar odds for onset of bipolar disorders (OR:1.72) or depressive disorders (OR:1.62). The magnitude of associations differed according to type of exposure and was greatest for sleep disturbances that met established diagnostic criteria for a sleep disorder (OR: 2.53). However, studies that examined observer or self-rated symptoms, also reported a significant association between hypersomnia symptoms and the onset of a major mental disorder (OR:1.39). Overall study quality was moderate with evidence of publication bias and meta-regression identified confounders such as year of publication. We conclude that evidence indicates that subjective, observer and objective studies demonstrate a modest but significant increase in the likelihood of first onset of mood and psychotic disorders in adolescence and early adulthood in individuals with broadly defined sleep disturbances. Although findings support proposals for interventions for sleep problems in youth, we suggest a need for greater consensus on screening strategies and for more longitudinal, prospective studies of circadian sleep-wake cycle dysrhythmias in youth.

The Role of Gut Microbiota in the High-Risk Construct of Severe Mental Disorders: A Mini Review

Severe mental disorders (SMD) are highly prevalent psychiatric conditions exerting an enormous toll on society. Therefore, prevention of SMD has received enormous attention in the last two decades. Preventative approaches are based on the knowledge and detailed characterization of the developmental stages of SMD and on risk prediction. One relevant biological component, so far neglected in high risk research, is microbiota. The human microbiota consists in the ensemble of microbes, including viruses, bacteria, and eukaryotes, that inhabit several ecological niches of the organism. Due to its demonstrated role in modulating illness and health, as well in influencing behavior, much interest has focused on the characterization of the microbiota inhabiting the gut. Several studies in animal models have shown the early modifications in the gut microbiota might impact on neurodevelopment and the onset of deficits in social behavior corresponding to distinct neurosignaling alterations. However, despite this evidence, only one study investigated the effect of altered microbiome and risk of developing mental disorders in humans, showing that individuals at risk for SMD had significantly different global microbiome composition than healthy controls. We then offer a developmental perspective and provided mechanistic insights on how changes in the microbiota could influence the risk of SMD. We suggest that the analysis of microbiota should be included in the comprehensive assessment generally performed in populations at high risk for SMD as it can inform predictive models and ultimately preventative strategies.

Lifetime psychopathology in child and adolescent offspring of parents diagnosed with schizophrenia or bipolar disorder: a 2-year follow-up study

Having one parent diagnosed with a severe mental disorder is considered one of the main risk factors for developing that disorder in adulthood, and it also increases the risk of a wide range of mental disorders in the offspring. The aim of this study is to compare the prevalence of several psychopathological diagnoses, the presence of prodromal symptoms, and global functioning in offspring of parents with schizophrenia or bipolar disorder and in offspring of controls at baseline and 2-year follow-up. This study included 41 offspring of parents with schizophrenia, 90 offspring of parents with bipolar disorder, and 107 offspring of controls (mean age 11.7 ± 3.2 at baseline and 13.9 ± 3.2 at follow-up). The prevalence of psychopathology and comorbidity was higher in offspring of parents with schizophrenia and offspring of parents with bipolar disorder than in offspring of controls at baseline and at 2-year follow-up. Interestingly, mood disorders were more prevalent in offspring of parents with bipolar disorder and disruptive disorders were more prevalent in offspring of parents with schizophrenia. Prodromal symptoms were more frequent in offspring of parents with schizophrenia than in offspring of controls, while the offspring of parents with bipolar disorder showed an intermediate pattern. Finally, global functioning was lower in the offspring of parents with schizophrenia than the offspring of parents with bipolar disorder and the offspring of controls. Screening patients' children is clinically relevant, since, as a group, they have an elevated risk of developing a psychiatric disorder and of experiencing their first symptoms during childhood and adolescence.

The Greater Houston Area Bipolar Registry-Clinical and Neurobiological Trajectories of Children and Adolescents With Bipolar Disorders and High-Risk Unaffected Offspring

The aims of this article are to discuss the rationale, design, and procedures of the Greater Houston Area Bipolar Registry (HBR), which aims at contributing to the effort involved in the investigation of neurobiological mechanisms underlying bipolar disorder (BD) as well as to identify clinical and neurobiological markers able to predict BD clinical course. The article will also briefly discuss examples of other initiatives that have made fundamental contributions to the field. This will be a longitudinal study with participants aged 6-17 at the time of enrollment. Participants will be required to meet diagnostic criteria for BD, or to be offspring of a parent with BD. We will also enroll healthy controls. Besides clinical information, which includes neurocognitive performance, participants will be asked to provide blood and saliva samples as well as to perform neuroimaging exams at baseline and follow-ups. Several studies point to the existence of genetic, inflammatory, and brain imaging alterations between individuals at higher genetic risk for BD compared with healthy controls. Longitudinal designs have shown high conversion rates to BD among high-risk offspring, with attempts to identify clinical predictors of disease onset, as well as clarifying the burden associated with environmental stressors. The HBR will help in the worldwide effort investigating the clinical course and neurobiological mechanisms of affected and high-risk children and adolescents with BD.

Association of Outdoor Artificial Light at Night With Mental Disorders and Sleep Patterns Among US Adolescents

IMPORTANCE

Indoor nighttime light exposure influences sleep and circadian rhythms and is known to affect mood-associated brain circuits in animals. However, little is known about the association between levels of nighttime outdoor light and sleep and mental health in the population, especially among adolescents.

OBJECTIVE

To estimate associations of outdoor artificial light at night (ALAN) with sleep patterns and past-year mental disorder among US adolescents.

DESIGN, SETTING, AND PARTICIPANTS

This population-based, cross-sectional study of US adolescents used the National Comorbidity Survey-Adolescent Supplement, a nationally representative cross-sectional survey conducted from February 2001 through January 2004. A probability sample of adolescents aged 13 to 18 years was included. Analyses were conducted between February 2019 and April 2020.

EXPOSURES

Levels of outdoor ALAN, measured by satellite, with means calculated within census block groups. ALAN values were transformed into units of radiance (nW/cm2/sr).

MAIN OUTCOMES AND MEASURES

Self-reported habitual sleep patterns (weeknight bedtime, weeknight sleep duration, weekend bedtime delay, and weekend oversleep) and past-year mood, anxiety, behavior, and substance use disorders, measured via an in-person structured diagnostic interview. Parent-reported information was included in behavior disorder diagnoses.

RESULTS

Among 10 123 adolescents (4953 boys [51.3%]; mean [SE] age, 15.2 [0.06] years [weighted]; 6483 for behavior disorder outcomes), ALAN was positively associated with indicators of social disadvantage, such as racial/ethnic minority status (median [IQR] ALAN: white adolescents, 12.96 [30.51] nW/cm2/sr; Hispanic adolescents: 38.54 [47.84] nW/cm2/sr; non-Hispanic black adolescents: 37.39 [51.88] nW/cm2/sr; adolescents of other races/ethnicities: 30.94 [49.93] nW/cm2/sr; P < .001) and lower family income (median [IQR] ALAN by family income-to-poverty ratio ≤1.5: 26.76 [52.48] nW/cm2/sr; >6: 21.46 [34.38] nW/cm2/sr; P = .005). After adjustment for several sociodemographic characteristics, as well as area-level population density and socioeconomic status, this study found that higher ALAN levels were associated with later weeknight bedtime, and those in the lowest quartile of ALAN reported the longest weeknight sleep duration. Those in the highest quartile of ALAN went to bed 29 (95% CI, 15-43) minutes later and reported 11 (95% CI, 19-2) fewer minutes of sleep than those in the lowest quartile. ALAN was also positively associated with prevalence of past-year mood and anxiety disorder: each median absolute deviation increase in ALAN was associated with 1.07 (95% CI, 1.00-1.14) times the odds of mood disorder and 1.10 (95% CI, 1.05-1.16) times the odds of anxiety disorder. Further analyses revealed associations with bipolar disorder (odds ratio [OR], 1.19 [95% CI, 1.05-1.35]), specific phobias (OR, 1.18 [95% CI, 1.11-1.26]), and major depressive disorder or dysthymia (OR, 1.07 [95% CI, 1.00-1.15]). Among adolescent girls, differences in weeknight bedtime by ALAN (third and fourth quartiles vs first quartile) were greater with increasing years since menarche (F3, 8.15; P < .001).

CONCLUSIONS AND RELEVANCE

In this study, area-level outdoor ALAN was associated with less favorable sleep patterns and mood and anxiety disorder in adolescents. Future studies should elucidate whether interventions to reduce exposure to ALAN may positively affect mental and sleep health.

Longitudinal trajectories of mood symptoms and global functioning in youth at high risk for bipolar disorder

BACKGROUND

Little is known about the longitudinal course of mood symptoms and functioning in youth who are at high risk for bipolar disorder (BD). Identifying distinct course trajectories and predictors of those trajectories may help refine treatment approaches.

METHODS

This study examined the longitudinal course of mood symptoms and functioning ratings in 126 youth at high risk for BD based on family history and early mood symptoms. Participants were enrolled in a randomized trial of family-focused therapy and followed longitudinally (mean 2.0 years, SD = 53.6 weeks).

RESULTS

Using latent class growth analyses (LCGA), we observed three mood trajectories. All youth started the study with active mood symptoms. Following the index mood episode, participants were classified as having a "significantly improving course" (n = 41, 32.5% of sample), a "moderately symptomatic course" (n = 21, 16.7%), or a "predominantly symptomatic course" (n = 64, 50.8%) at follow-up. More severe depression, anxiety, and suicidality at the study's baseline were associated with a poorer course of illness. LCGA also revealed three trajectories of global functioning that closely corresponded to symptom trajectories; however, fewer youth exhibited functional recovery than exhibited symptomatic recovery.

LIMITATIONS

Mood trajectories were assessed within the context of a treatment trial. Ratings of mood and functioning were based on retrospective recall.

CONCLUSIONS

This study suggests considerable heterogeneity in the course trajectories of youth at high risk for BD, with a significant proportion (32.5%) showing long-term remission of symptoms. Treatments that enhance psychosocial functioning may be just as important as those that ameliorate symptoms in youth at risk for BD.

Neurobiology of bipolar disorders: a review of genetic components, signaling pathways, biochemical changes, and neuroimaging findings

Bipolar disorder (BD) is a chronic mental illness characterized by changes in mood that alternate between mania and hypomania or between depression and mixed states, often associated with functional impairment. Although effective pharmacological and non-pharmacological treatments are available, several patients with BD remain symptomatic. The advance in the understanding of the neurobiology underlying BD could help in the identification of new therapeutic targets as well as biomarkers for early detection, prognosis, and response to treatment in BD. In this review, we discuss genetic, epigenetic, molecular, physiological and neuroimaging findings associated with the neurobiology of BD. Despite the advances in the pathophysiological knowledge of BD, the diagnosis and management of the disease are still essentially clinical. Given the complexity of the brain and the close relationship between environmental exposure and brain function, initiatives that incorporate genetic, epigenetic, molecular, physiological, clinical, environmental data, and brain imaging are necessary to produce information that can be translated into prevention and better outcomes for patients with BD.

Comorbidity and patterns of familial aggregation in attention-deficit/hyperactivity disorder and bipolar disorder in a family study of affective and anxiety spectrum disorders

The aim of this study is to examine the familial aggregation of Attention-deficit/hyperactivity disorder (ADHD) and its cross-transmission with bipolar disorder (BD) in a community-based family study of mood spectrum disorders. A clinically-enriched community sample of 562 probands recruited from the greater Washington, DC metropolitan area and their 698 directly interviewed relatives were included in analyses. Inclusion criteria were English speaking and consent to contact at least two first-degree relatives. Standard family study methodology was used and DSM-IV classified mental disorders were ascertained through a best-estimate procedure based on direct semi-structured interviews and multiple family history reports. There was specificity of familial aggregation of both bipolar I disorder (BD I) and bipolar II disorder (BD II) (i.e., BD I OR = 6.08 [1.66, 22.3]; BD II OR = 2.98 [1.11, 7.96]) and ADHD (ADHD OR = 2.13 [1.16, 3.95]). However, there was no evidence for cross-transmission of BD and ADHD in first degree relatives (i.e., did not observe increased rates of BD in relatives of those with ADHD and vice versa; all ps > 0.05). The specificity of familial aggregation of ADHD and BD alongside the absence of shared familial risk are consistent with the notion that the comorbidity between ADHD and BD may be attributable to diagnostic artifact, could represent a distinct BD suptype characterized by childhood-onset symptoms, or the possibility that attention problems serve as a precursor or consequence of BD.

Advances in early identification of children and adolescents at risk for psychiatric illness

PURPOSE OF REVIEW

Childhood and adolescence are a crucial time window for the early identification of perspectival risk for adult psychopathology. This article reviews current advances in the field.

RECENT FINDINGS

Converging developmentally focused and predictive approaches are rapidly expanding in the field of early identification of children and adolescents at risk for psychiatric illness. Although the former emphasizes early phenotypic trajectories emerging in childhood and adolescence, the latter operate in terms of clinical risk staging. Decisive advances in the field include the metaanalytical evidence of the predictive value of clinical high-risk criteria in childhood-adolescence; the systematization of premorbid manifestations of psychotic vulnerability and bipolar prodromes; the corroboration of certain sets of anomalous subjective experiences as transdiagnostic index of familial genetic risk (i.e., basic symptoms) and early developmental expression of schizophrenia spectrum vulnerability (i.e., self-disorders).

SUMMARY

Childhood phenotypic manifestations of liability to mental disorders are often cooccurrent and undergo a plastic, heterotypic modification along the transition to adolescence. In general, they represent epiphenomenic flags of a broad vulnerability for the subsequent structuration of mental illness. This perspective coheres with the p-factor model of psychopathology and complements the clinical staging model which informs the early detection paradigm of severe mental disorders.

A Naturalistic Study of Youth Referred to a Tertiary Care Facility for Acute Hypomanic or Manic Episode

Background: Bipolar Disorders (BD) in youth are a heterogeneous condition with different phenomenology, patterns of comorbidity and outcomes. Our aim was to explore the effects of gender; age at onset (prepubertal- vs. adolescent-onset) of BD; and elements associated with attention deficit hyperactivity disorder (ADHD) and Substance Use Disorder (SUD) comorbidities, severe suicidal ideation or attempts, and poorer response to pharmacological treatments. Method: 117 youth (69 males and 57 females, age range 7 to 18 years, mean age 14.5 ± 2.6 years) consecutively referred for (hypo)manic episodes according to the Diagnostic and Statistical Manual of Mental Disorders, 54th ed (DSM 5) were included. Results: Gender differences were not evident for any of the selected features. Prepubertal-onset BD was associated with higher rates of ADHD and externalizing disorders. SUD was higher in adolescent-onset BD and was associated with externalizing comorbidities and lower response to treatments. None of the selected measures differentiated patients with or without suicidality. At a 6-month follow up, 51.3% of the patients were responders to treatments, without difference between those receiving and not receiving a psychotherapy. Clinical severity at baseline and comorbidity with Conduct Disorder (CD) and SUD were associated with poorer response. Logistic regression indicated that baseline severity and number of externalizing disorders were associated with a poorer outcome. Conclusions: Disentangling broader clinical conditions in more specific phenotypes can help timely and focused preventative and therapeutic interventions.

Efficacy of cognitive-behavioral group therapy in patients at risk for serious mental illness presenting with subthreshold bipolar symptoms: Results from a prespecified interim analysis of a multicenter, randomized, controlled study

OBJECTIVE

Most patients with bipolar disorders (BD) exhibit prodromal symptoms before a first (hypo)manic episode. Patients with clinically significant symptoms fulfilling at-risk criteria for serious mental illness (SMI) require effective and safe treatment. Cognitive-behavioral psychotherapy (CBT) has shown promising results in early stages of BD and in patients at high risk for psychosis. We aimed to investigate whether group CBT can improve symptoms and functional deficits in young patients at risk for SMI presenting with subthreshold bipolar symptoms.

METHOD

In a multicenter, randomized, controlled trial, patients at clinical risk for SMI presenting with subthreshold bipolar symptoms aged 15-30 years were randomized to 14 weeks of at-risk for BD-specific group CBT or unstructured group meetings. Primary efficacy endpoints were differences in affective symptomatology and psychosocial functioning at 14 weeks. At-risk status was defined as a combination of subthreshold bipolar symptomatology, reduction of psychosocial functioning and a family history for (schizo)affective disorders. A prespecified interim analysis was conducted at 75% of the targeted sample.

RESULTS

Of 128 screened participants, 75 were randomized to group CBT (n = 38, completers = 65.8%) vs unstructured group meetings (n = 37, completers = 78.4%). Affective symptomatology and psychosocial functioning improved significantly at week 14 (P < .001) and during 6 months (P < .001) in both groups, without significant between-group differences. Findings are limited by the interim character of the analysis, the use of not fully validated early detection interviews, a newly adapted intervention manual, and the substantial drop-outs.

CONCLUSIONS

Results suggest that young patients at-risk for SMI presenting with subthreshold bipolar symptoms benefit from early group sessions. The degree of specificity and psychotherapeutic interaction needed requires clarification.

Trends in the incidence and DALYs of bipolar disorder at global, regional, and national levels: Results from the global burden of Disease Study 2017

The objective of this study is to assess the global, regional, and national burden of bipolar disorder (BPD) from 1990 to 2017, by gender, age, and social-demographic index (SDI) from the 2017 Global Burden of Disease (GBD) study. We collected detailed information from GBD on the numbers of incidence cases and disability-adjusted life years (DALYs), age-standardized incidence rate (ASIR), and age-standardized DALYs rate (ASDR) during 1990-2017. Estimated annual percentage changes (EAPCs) were calculated to assess ASIR and ASDR trends. GBD data estimated that BPD incidences increased by 47.74%, from 3.06 million in 1990 to 4.53 million in 2017, and the DALYs increased by 54.4%, from 6.02 million in 1990 to 9.29 million in 2017. Over the 28-year period between 1990 and 2017, the ASIR and ASDR increased only slightly (EAPC = 0.14 and 0.05 for ASIR and ASDR, respectively). Subjects aged 10-19 years contributed the most to the total number of incidence cases, while those aged 20-44 years contributed the most to the number of DALYs. The ASIR and ASDR were highest in tropical Latin America and lowest in East Asia. Areas in the lowest sociodemographic index (SDI) quintile showed the highest ASIR (about 64/100,000), and those in the highest SDI quintile showed the highest ASDR (about 140/100,000). In conclusion, while the ASIR and ASDR due to BPD have been stable, the absolute incidence and DALYs remain high, which represents an increasing burden on health-care systems.

Aerobic exercise impacts the anterior cingulate cortex in adolescents with subthreshold mood syndromes: a randomized controlled trial study

Aerobic exercise is effective in alleviating mood symptoms while the mechanism is poorly understood. There are limited clinical trials that investigated the effect of exercise on the anterior cingulate cortex (ACC), a key brain region involved in mood regulations, in adolescents with subthreshold mood syndromes. This randomized controlled trial (RCT) of aerobic exercise was undertaken in a middle school in Guangzhou, China. Participants were adolescents aged 12-14 with subthreshold mood syndromes including depressive and manic symptoms and were randomly assigned to an aerobic exercise intervention or a psychoeducation control group. Participants in the exercise group received moderate-intensity exercise intervention, consisting of 30 mins running, 4 days per week for 3 months. The primary outcome in this study was structural changes in the ACC from baseline to post intervention. The trial was registered with ClinicalTrial.gov (NCT03300778). Of 56 participants who met the criteria for subthreshold mood syndromes, 39 (41.03% males) had complete MRI data, with 20 and 19 subjects in the exercise and control group, respectively. At baseline, demographic information (e.g., age and sex), clinical symptoms, and the gray matter volume and cortical thickness of ACC were matched between the two groups. After 12 weeks of treatment, participants in the exercise group displayed increased gray matter volume of the left rostral ACC (F_1,30 = 5.73, p = 0.02) and increased cortical thickness of the right rostral ACC (F_1,30 = 7.83, p = 0.01) when compared with the control group. No significant differences were found for caudal ACC cortical thickness and gray matter volume. Our data demonstrate that 12-week, moderate-intensity aerobic exercise can induce structural changes in the rostral ACC in adolescents with subthreshold mood syndromes.

Pre-pubertal bipolar disorder: origins and current status of the controversy

BACKGROUND

Evidence from epidemiological, clinical and high-risk studies has established that the peak period of risk for onset of bipolar disorder spans late adolescence and early adulthood. However, the proposal of the existence of a pre-pubertal form of bipolar disorder manifesting in early childhood created substantial debate. In this narrative review, the literature and contributing factors pertaining to the controversy surrounding the proposed pre-pubertal bipolar disorder subtype are discussed. The resolution of the debate and lessons learned are highlighted.

MAIN BODY

In the mid 1990s US researchers proposed that chronic irritability and explosive temper in pre-pubertal children with pre-existing ADHD and/or other learning and developmental disorders might represent a variant of mania. A number of factors contributed to this proposal including severely ill children with no diagnostic home given changes in the ADHD DSM diagnostic criteria and over-reliance on symptoms and structured interviews rather than on a clinical assessment incorporating developmental history, social context and clinical course. Prospective studies of children at high familial risk did not support the proposed pre-pubertal bipolar phenotype; but rather provided convergent evidence that bipolar disorder onset in adolescence and early adulthood not uncommonly preceded by sleep and internalizing symptoms and most often debuting as depression in adolescence (after puberty). Epidemiological studies of population and hospital discharge data provided evidence that the pre-pubertal bipolar phenotype was largely a US driven phenomenon.

CONCLUSIONS

Psychiatric diagnosis is particularly challenging given the current lack of objective biomarkers. However, validity and utility of clinical diagnoses can be strengthened if all available predictive information is used to formulate a diagnosis. As in other areas of medicine, critical information required to make a valid diagnosis includes developmental history, clinical course, family history and treatment response-weighed against the known trajectories of classical disorders. Moreover, given that psychiatric disorders are in evolution over childhood and adolescence and symptoms, in of themselves, are often non-specific, a thorough clinical assessment incorporating collateral history and psychosocial context is paramount. Such an approach might have avoided or at least brought a more timely resolution to the debate on pre-pubertal mania.

What is bipolar disorder? A disease model of dysregulated energy expenditure

Advances in the understanding and management of bipolar disorder (BD) have been slow to emerge. Despite notable recent developments in neurosciences, our conceptualization of the nature of this mental disorder has not meaningfully progressed. One of the key reasons for this scenario is the continuing lack of a comprehensive disease model. Within the increasing complexity of modern research methods, there is a clear need for an overarching theoretical framework, in which findings are assimilated and predictions are generated. In this review and hypothesis article, we propose such a framework, one in which dysregulated energy expenditure is a primary, sufficient cause for BD. Our proposed model is centered on the disruption of the molecular and cellular network regulating energy production and expenditure, as well its potential secondary adaptations and compensatory mechanisms. We also focus on the putative longitudinal progression of this pathological process, considering its most likely periods for onset, such as critical periods that challenges energy homeostasis (e.g. neurodevelopment, social isolation), and the resulting short and long-term phenotypical manifestations.

Characteristics of youth at high risk for bipolar disorder compared to youth with bipolar I or II disorder

Significant efforts have been undertaken to characterize the phenomenology of the high-risk period for bipolar disorder (BD) through the examination of youth at familial risk (i.e., having a first- or second-degree relative with BD) or clinical high risk for the disorder (i.e., youth with BD Not Otherwise Specified [NOS] or major depressive disorder [MDD]). However, little is known about the phenomenology of youth at both familial and clinical high risk for BD. In this study, we examined the clinical and psychosocial characteristics of youth at familial and clinical high risk (HR) for BD, and compared these characteristics to those of youth with BD I and II. Both groups were recruited based on current, active mood symptoms from separate randomized trials of family therapy. A total of 127 HR youth were evaluated: 52 (40.9%) were diagnosed with BD-NOS and 75 (59.1%) were diagnosed with MDD. Compared to adolescents with BD I and II (n = 145), HR youth had higher rates of anxiety disorders, and comparable rates of attention-deficit/hyperactivity disorder and oppositional defiant disorder/conduct disorder. Manic symptom severity and psychosocial functioning were progressively more impaired consistent with diagnostic severity: BD I > BD II > BD-NOS > MDD. Nonetheless, HR youth exhibited depressive symptom severity that was comparable to adolescents with BD I. These results provide further support for the high rates of anxiety disorders and premorbid dysfunction in addition to active mood symptoms for youth at risk for BD, and suggest anxiety is an important phenomenological characteristic and treatment target in the high-risk period.

Longitudinal course and risk factors associated with psychosis in bipolar youths

OBJECTIVES

To compare the longitudinal clinical course of youths with bipolar disorder (BD) spectrum with lifetime (past, intake, and/or follow-up) psychosis (BDP+) to youths with BD without lifetime psychosis (BDP-). Also, to identify risk factors associated with increased risk of first onset of psychosis during prospective follow-up.

METHOD

Bipolar disorder youths (BDP+ = 137, BDP- = 233), aged 7-17 years old, were followed on average every 7 months for 11.7 years and were evaluated using standardized instruments. Data were analyzed using linear and generalized linear models for the full sample, as well as for youths who developed first period of psychosis (n = 55).

RESULTS

After adjusting for confounders, BDP+ youths with one, and in particular ≥2 lifetime psychotic episodes, had higher rates and more severe mood and anxiety symptoms, higher rates of suicidality, psychiatric hospitalizations, and sexual/physical abuse, and poorer psychosocial functioning than BDP- youths. Even before the first onset of psychosis during follow-up, BDP+ youths showed more psychopathology and had more family history of psychiatric illness than those who never developed psychosis. First-onset psychosis was associated with low socioeconomic status (SES), living with one parent, bipolar disorder type one and type two, comorbid anxiety, history of hospitalizations, and family history of mania and suicidality.

CONCLUSION

BDP+ is associated with poor prognosis and worse clinical picture, even before the onset of psychosis, indicating the need for prompt identification and treatment of these youths. Studies aimed to treat acute symptoms of psychosis, as well as prevent the onset of psychosis, including risk factors amenable to change, are warranted.

Affective Disorders with Psychosis in Youth: An Update

Mood disorders, including major depression and mania, can present with psychotic features. In youth psychotic-like phenomena such as "seeing faces in the dark" or "hearing noises" are fairly common. Rates of lifetime psychotic symptoms are much higher than rates of psychosis during a "current" episode of mania or depression in youth. Psychotic phenomena can be mood congruent or incongruent. A detailed mental status examination and clinical history include questioning to ensure the informants understand the questions being asked. There are interviews that structure how questions are asked, and rating scales that help anchor severity and quality of the mood episode.

Machine learning and big data analytics in bipolar disorder: A position paper from the International Society for Bipolar Disorders Big Data Task Force

OBJECTIVES

The International Society for Bipolar Disorders Big Data Task Force assembled leading researchers in the field of bipolar disorder (BD), machine learning, and big data with extensive experience to evaluate the rationale of machine learning and big data analytics strategies for BD.

METHOD

A task force was convened to examine and integrate findings from the scientific literature related to machine learning and big data based studies to clarify terminology and to describe challenges and potential applications in the field of BD. We also systematically searched PubMed, Embase, and Web of Science for articles published up to January 2019 that used machine learning in BD.

RESULTS

The results suggested that big data analytics has the potential to provide risk calculators to aid in treatment decisions and predict clinical prognosis, including suicidality, for individual patients. This approach can advance diagnosis by enabling discovery of more relevant data-driven phenotypes, as well as by predicting transition to the disorder in high-risk unaffected subjects. We also discuss the most frequent challenges that big data analytics applications can face, such as heterogeneity, lack of external validation and replication of some studies, cost and non-stationary distribution of the data, and lack of appropriate funding.

CONCLUSION

Machine learning-based studies, including atheoretical data-driven big data approaches, provide an opportunity to more accurately detect those who are at risk, parse-relevant phenotypes as well as inform treatment selection and prognosis. However, several methodological challenges need to be addressed in order to translate research findings to clinical settings.

Investigating the association between anxiety symptoms and mood disorder in high-risk offspring of bipolar parents: a comparison of Joint and Cox models

BACKGROUND

Anxiety is associated with mood disorders including bipolar disorder. Two statistical modelling frameworks were compared to investigate the longitudinal relationship between repeatedly measured anxiety symptoms and the onset of depression and bipolar disorder in youth at confirmed familial risk.

METHODS

Prospectively collected data on 156 offspring of a parent with confirmed bipolar disorder participating in the Canadian Flourish high-risk offspring longitudinal cohort study were used for this analysis. As part of the research protocol at approximately yearly visits, a research psychiatrist completed the HAM-A and a semi-structured diagnostic research interview following KSADS-PL format. Diagnoses using DSM-IV criteria were made on blind consensus review of all available clinical information. We investigated two statistical approaches, Cox model and Joint model, to evaluate the relationship between repeated HAM-A scores and the onset of major depressive or bipolar disorder. The Joint model estimates the trajectory of the longitudinal variable using a longitudinal sub-model and incorporates this estimated trajectory into a Cox sub-model.

RESULTS

There was evidence of an increased hazard of major mood disorder for high-risk individuals with higher HAM-A scores under both modelling frameworks. After adjusting for other covariates, a one-unit increase in log-transformed HAM-A score was associated with a hazard ratio of 1.74 (95% CI (1.12, 2.72)) in the Cox model compared to 2.91(95% CI (1.29, 6.52)) in the Joint model. In an exploratory analysis there was no evidence that family clustering substantially affected the conclusions.

CONCLUSIONS

Estimated effects from the conventional Cox model, which is often the model of choice, were dramatically lower in this dataset, compared to the Joint model. While the Cox model is often considered the approach of choice for analysis, research has shown that the Joint model may be more efficient and less biased. Our analysis based on a Joint model suggests that the magnitude of association between anxiety and mood disorder in individuals at familial risk of developing bipolar disorder may be stronger than previously reported.

Epigenetic markers in inflammation-related genes associated with mood disorder: a cross-sectional and longitudinal study in high-risk offspring of bipolar parents

Bipolar disorder is highly heritable and typically onsets in late adolescence or early adulthood. Evidence suggests that immune activation may be a mediating pathway between genetic predisposition and onset of mood disorders. Building on a prior study of mRNA and protein levels in high-risk offspring published in this Journal, we conducted a preliminary examination of methylation profiles in candidate immune genes from a subsample of well-characterized emergent adult (mean 20 years) offspring of bipolar parents from the Canadian Flourish high-risk cohort. Models were adjusted for variable age at DNA collection, sex and antidepressant and mood stabilizer use. On cross-sectional analysis, there was evidence of higher methylation rates for BDNF-1 in high-risk offspring affected (n = 27) and unaffected (n = 23) for mood disorder compared to controls (n = 24) and higher methylation rates in affected high-risk offspring for NR3C1 compared to controls. Longitudinal analyses (25 to 34 months) provided evidence of steeper decline in methylation rates in controls (n = 24) for NR3C1 compared to affected (n = 15) and unaffected (n = 11) high-risk offspring and for BDNF-2 compared to affected high-risk. There was insufficient evidence that changes in any of the candidate gene methylation rates were associated with illness recurrence in high-risk offspring. While preliminary, findings suggest that longitudinal investigation of epigenetic markers in well-characterized high-risk individuals over the peak period of risk may be informative to understand the emergence of bipolar disorder.

Reporting guidelines on remotely collected electronic mood data in mood disorder (eMOOD)-recommendations

Prospective monitoring of mood was started by Kraepelin who made and recorded frequent observations of his patients. During the last decade, the number of research studies using remotely collected electronic mood data has increased markedly. However, standardized measures and methods to collect, analyze and report electronic mood data are lacking. To get better understanding of the nature, correlates and implications of mood and mood instability, and to standardize this process, we propose guidelines for reporting of electronic mood data (eMOOD). This paper provides an overview of remotely collected electronic mood data in mood disorders and discusses why standardized reporting is necessary to evaluate and inform mood research in Psychiatry. Adherence to these guidelines will improve interpretation, reproducibility and future meta-analyses of mood monitoring in mood disorder research.

Psychological interventions for young people at risk for bipolar disorder: A systematic review

OBJECTIVES

Several studies have recently been conducted that have explored the benefits of psychological interventions in reducing symptomatology or improving outcomes in young people at-risk of developing bipolar disorder. The aim of this review was to explore if such interventions reduce current psychiatric symptoms and prevent the development of new symptoms.

METHODS

A systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Databases searched were MEDLINE, EMBASE, PsychInfo, CINAHL and SCOPUS from January 1990 until August 2018. The inclusion criteria were young people aged under 30 years with a family history of bipolar disorder and any empirical studies that contained a psychological or psychoeducation intervention.

RESULTS

A total of 7 articles (N = 138, 55 males) were included (mean age ranged from 12 to 15 years). Interventions conducted included Family Focussed Therapy, Interpersonal and Social Rhythm Therapy, and Mindfulness-based Cognitive Therapy for Children. Significant results were found in some studies, depending on the sample's initial symptoms, with reduced time to relapse and reduced symptoms of anxiety, depression and hypo/mania being found.

LIMITATIONS

No studies have explored if interventions may delay the time to onset of first hypo/manic episodes and only two randomised controlled trials were identified.

CONCLUSIONS

Some significant results were noted with lower symptoms of anxiety, depression and hypo/mania being found in some studies. It is currently unclear if psychological interventions may prevent the development of bipolar disorder or other psychiatric symptoms over time; further longitudinal studies are required.

What Would Digital Early Intervention for Bipolar Disorder Look Like? Theoretical and Translational Considerations for Future Therapies

There are growing calls for the development of early intervention/preventive interventions for young people identified to be at risk of bipolar disorder (BD), and digital delivery appears to be a strong candidate delivery method. To date, no such interventions exist, and the aim of this perspective paper is to advance the literature by reviewing theoretical issues related to early intervention in BD and introducing a framework for design of feasible, acceptable, and effective online psychosocial interventions for this population. It is concluded that, by adopting an appropriate transdiagnostic and humanistic framework, and recognizing emerging tenets of digital psychotherapy development, testable online interventions for young people at risk of BD are within reach.