Risk Factors For Bipolar Disorder Research Articles

The implication of ADRA2A and AVPRIB gene variants in the aetiology of stress-related bipolar disorder

ObjectiveBipolar disorder is a complex and severe mental illness characterised by manic and depressive episodes that can be triggered and exacerbated by psychosocial, environmental, and biological stressors. Genetic variations are a risk factor for bipolar disorder. However, the identification of the exact gene variants and genotypes remains complex. This study, therefore, aims to identify the potential association between genotypes of analysed single nucleotide polymorphisms and the presence of a stressor in bipolar disorder patients. MethodWe analysed 114 single nucleotide polymorphisms (SNPs) from bipolar and stress-related candidate genes in 550 patients with bipolar disorders (60.36 % females and 39.64 % male). We compared SNPs of patients reporting the presence (40.73 %) or absence of stressors (59.27 %) before the first episode using the Persons Chi-square test and Bayes Factor t-test. The genotyping of 114 SNPs was done using TaqMan assays. Statistical analysis was done using Statistica 13.3 software (StatSoft Poland, Krakow, Poland), R programming, and G*Power statistics. ResultWe found significant differences in genotype distribution (p < 0.05) in 6 polymorphisms (AVPRIB/rs28536160, FKBP4/rs2968909, ADRA2A/rs3750625, 5HTR2A/rs6311, 5HTR2A/rs6313, and GLCCI1/rs37972) when comparing BD patient with and without stressor with a small effect of d = 0.2. Of these, two gene variants (ADRA2A/rs3750625/AC and AVPRIB/rs28536160/CT) with minor alleles formed an association with the presence of a stressor prior to the disease onset and favoured the alternative hypothesis using Bayes Factor Analysis t-test for hypothesis testing. ConclusionThis study presents a novel association of ADRA2A/rs3750625/AC and AVPR1B/rs28536160/CT gene variants in stress-related bipolar disorder with the AC genotype of ADRA2A/rs3750625 constituting a risk genotype and CT of AVPR1B/rs28536160 constituting a protective genotype. However, further functional analysis is required to fully understand their clinical and biological significance and interaction.

Uncovering novel drug targets for bipolar disorder: a Mendelian randomization analysis of brain, cerebrospinal fluid, and plasma proteomes.

There is a clear demand for innovative therapeutics for bipolar disorder (BD). We integrated the largest BD genome-wide association study (GWAS) dataset (NCase = 41 917, NControl = 371 549) with protein quantitative trait loci from brain, cerebrospinal fluid, and plasma. Using a range of integrative analyses, including Mendelian randomization (MR), Steiger filter analysis, Bayesian colocalization, and phenome-wide MR analysis, we prioritized novel drug targets for BD. Additionally, we incorporated data from the UK Biobank (NCase = 1064, NControl = 365 476) and the FinnGen study (NCase = 7006, NControl = 329 192) for robust biological validation. Through MR analysis, we found that in the brain, downregulation of DNM3, MCTP1, ABCB8 and elevation of DFNA5 and PDF were risk factors for BD. In cerebrospinal fluid, increased BD risk was associated with increased levels of FRZB, AGRP, and IL36A and decreased CTSF and LRP8. Plasma analysis revealed that decreased LMAN2L, CX3CL1, PI3, NCAM1, and TIMP4 correlated with increased BD risk, but ITIH1 did not. All these proteins passed Steiger filtering, and Bayesian colocalization confirmed that 12 proteins were colocalized with BD. Phenome-wide MR analysis revealed no significant side effects for potential drug targets, except for LRP8. External validation further underscored the concordance between the primary and validation cohorts, confirming MCTP1, DNM3, PDF, CTSF, AGRP, FRZB, LMAN2L, NCAM1, and TIMP4 are intriguing targets for BD. Our study identified druggable proteins for BD, including MCTP1, DNM3, and PDF in the brain; CTSF, AGRP, and FRZB in cerebrospinal fluid; and LMAN2L, NCAM1, and TIMP4 in plasma, delineating promising avenues to development of novel therapies.

Bipolar Disorder with History of Physical Abuse and Comorbid Polycythemia Vera: a Case Report

Introductions: Based on a 2015 United Nations Children’s Fund (UNICEF) report, violence against children is widespread in Indonesia; 40% of 13–15-year-old children reported being physically assaulted at least once a year, 26% reported being physically abused by a parent or caregiver, and 50% reported being bullied at school. Case: A 23-year-old female patient, Hindu, Balinese, unmarried, and unemployed, came alone to the psychiatric polyclinic of Wangaya Hospital. From history taking, there was dizziness, anhedonia, impaired attention, reduced self-esteem and confidence, guilt and uselessness, reference ideas, somatic delusions, relationship mood, logorrhea and flight of ideas, a history of mixed-type insomnia, and excessive energy. In a general examination, there were icteric sclera and palpable enlargement of the spleen (Schuffner 4). Neurological examination within normal limits. Discussion: The patient has bipolar disorder, caused by a traumatic experience in childhood. The patient was found to have a history of repeated treatment; she was initially diagnosed with bipolar disorder and received Depakote 250 mg and Clobazam 10 mg. Then, the patient came for treatment again at Wangaya Hospital on August 30, 2021, because of a headache and was diagnosed with bipolar affective disorder, with the current episode being moderately depressive with somatic symptoms. Conclusion: Traumatic childhood events are a risk factor for bipolar disorder. In addition to poor clinical presentation, the early onset of bipolar disorder is also an aggravating factor for symptom recurrence. Polycythemia vera can be a complicating factor in the recovery and relapse of bipolar disorder.

Effects of CACNA1C and ANK3 on cognitive function in patients with bipolar disorder

Bipolar disorder (BD) is a complex, severe mental illness with cognitive impairment. Impairments in attention and memory are particularly evident. A large number of previous studies have identified CACNA1C and ANK3 gene variants as risk factors for BD and both affect cognitive function in people with BD. However, it is unclear whether there is an interaction effects between the two genes on cognitive impairment in patients. We used 153 Chinese Han Chinese patients with BD to explore the association of CACNA1C and ANK3 variants with attention and immediate memory using Plink software and and performed a epistatic interaction effects analysis. We found that CACNA1C and ANK3 gene variants respectively affected patients' scores on attention and memory tests. The significant SNP in the CACNA1C and ANK3 genes are rs73042126(P = 3.16 × 10−5,FDR = 0.0253) and rs2393640(P = 1.50 × 10−4,FDR = 0.0353) respectively. And they also interacted to affect cognitive functioning in BD patients (attention: P = 0.0289; immediate memory: P = 0.0398). Follow-up studies should increase the sample size, improve the assessment methods and experimental design, and further explore the pathogenic mechanisms of BD.

Multifactorial etiology of manic episodes. About a case

IntroductionManic episodes have a multifactorial etiology, with frequent association with genetic factors, comorbidities such as systemic diseases or secondary to infectious diseases, and environmental exposure factors. The prevalence of bipolar disorder is markedly higher in patients with autoimmune disease. The risk of developing bipolar disorder in some studies has been seen to be higher among patients with rheumatoid arthritis, therefore chronic inflammation would be a potential mechanism and could be a modifiable risk factor for bipolar disorder. Growing evidence indicates that Sars-CoV-2 may also trigger the acute onset of mood disorders or psychotic symptoms.ObjectivesWe present the case of a patient who presents symptoms compatible with an acute manic episode after an outbreak of rheumatoid arthritis and comorbid COVID infection.Methods52-year-old patient. She went to the hospital emergency room presenting affective symptoms compatible with a manic episode and psychomotor agitation. Personal medical history: rheumatoid arthritis, antiphospholipid syndrome. Psychiatric personal history: Depressive disorder under follow-up by a private psychiatrist under treatment with antidepressants. During the interview, the patient presented accelerated speech, with great emotional incontinence. Saltigrade thought and tachypsychia. She verbalizes delusional ideas of megalomaniacal and mystical and religious characteristics. She verbalizes that she is the reincarnation of the holy spirit, that God has taken her body and speaks through her. In the emergency room, a Sars-CoV-2 infection that the patient was unaware of was diagnosed. She is admitted to the hospital in the mental health unit, in the first interviews the patient maintains speech with delusional ideas “I notice the stigmata of Christ on my body”.ResultsThe patient recovers after treatment for the COVID infection, remaining asymptomatic. It was decided to start lithium to stabilize mood and the patient presented good tolerance and treatment with antipsychotics. The patient presented a favorable response, remitting the psychotic symptoms of which she was critical and stabilizing the affective symptoms. The patient is diagnosed with Severe Manic Episode with Psychotic Symptoms, as the main diagnosis and we could conclude the diagnosis of Bipolar Disorder since she has presented 2 depressive episodes in the past that have required treatment and follow-up by psychiatry.ConclusionsManic episodes have a multifactorial etiology and require an individualized approach, and comorbid medical conditions must always be assessed in order to establish a therapeutic plan with patients.Disclosure of InterestNone Declared

Associations of altered leukocyte DDR1 promoter methylation and childhood trauma with bipolar disorder and suicidal behavior in euthymic patients.

Altered DNA methylation (DNAm) patterns of discoidin domain receptor 1 (DDR1) have been found in the blood and brain of patients with schizophrenia (SCZ) and the brain of patients with bipolar disorder (BD). Childhood trauma (CT) is associated with changes in DNAm that in turn are related to suicidal behavior (SB) in patients with several psychiatric disorders. Here, using MassARRAY® technology, we studied 128 patients diagnosed with BD in remission and 141 healthy controls (HCs) to compare leukocyte DDR1 promoter DNAm patterns between patients and HCs and between patients with and without SB. Additionally, we investigated whether CT was associated with DDR1 DNAm and mediated SB. We found hypermethylation at DDR1 cg19215110 and cg23953820 sites and hypomethylation at cg14279856 and cg03270204 sites in patients with BD compared to HCs. Logistic regression models showed that hypermethylation of DDR1 cg23953820 but not cg19215110 and CT were risk factors for BD, while cg14279856 and cg03270204 hypomethylation were protective factors. In patients, CT was a risk factor for SB, but DDR1 DNAm, although associated with CT, did not mediate the association of CT with SB. This is the first study demonstrating altered leukocyte DDR1 promoter DNAm in euthymic patients with BD. We conclude that altered DDR1 DNAm may be related to immune and inflammatory mechanisms and could be a potential blood biomarker for the diagnosis and stratification of psychiatric patients.

A Metabolome-Wide Mendelian Randomization Study Identifies Dysregulated Arachidonic Acid Synthesis as a Potential Causal Risk Factor for Bipolar Disorder

BackgroundBipolar disorder (BPD) is a debilitating mood disorder with an unclear etiology. A better understanding of the underlying pathophysiological mechanisms will help to identify novel targets for improved treatment options and prevention strategies. In this metabolome-wide Mendelian randomization study, we screened for metabolites that may have a causal role in BPD. MethodsWe tested a total of 913 circulating metabolite exposures assessed in 14,296 Europeans using a mass spectrometry-based platform. For the BPD outcome, we used summary data from the largest and most recent genome-wide association study reported to date, including 41,917 BPD cases. ResultsWe identified 33 metabolites associated with BPD (padjusted < 5.48 × 10−5). Most of them were lipids, including arachidonic acid (β = −0.154, SE = 0.023, p = 3.30 × 10−11), a polyunsaturated omega-6 fatty acid, along with several complex lipids containing either an arachidonic or a linoleic fatty acid side chain. These associations did not extend to other closely related psychiatric disorders like schizophrenia or depression, although they may be involved in the regulation of lithium response. These lipid associations were driven by genetic variants within the FADS1/2/3 gene cluster, which is a robust BPD risk locus encoding a family of fatty acid desaturase enzymes that are responsible for catalyzing the conversion of linoleic acid into arachidonic acid. Statistical colocalization analyses indicated that 27 of the 33 metabolites shared the same genetic etiology with BPD at the FADS1/2/3 cluster, demonstrating that our findings are not confounded by linkage disequilibrium. ConclusionsOverall, our findings support the notion that arachidonic acid and other polyunsaturated fatty acids may represent potential targets for BPD.

Bipolar Patient–Specific In Vitro Diagnostic Test Reveals Underlying Cardiac Arrhythmia Phenotype Caused by Calcium Channel Genetic Risk Factor

A common genetic risk factor for bipolar disorder is CACNA1C, a gene that is also critical for cardiac rhythm. The impact of CACNA1C mutations on bipolar patient cardiac rhythm is unknown. Here, we report the cardiac electrophysiological implications of a bipolar disorder–associated genetic risk factor in CACNA1C using patient induced pluripotent stem cell-derived cardiomyocytes. Results indicate that the CACNA1C bipolar disorder–related mutation causes cardiac electrical impulse conduction slowing mediated by impaired intercellular coupling via connexin 43 gap junctions. In vitro gene therapy to restore connexin 43 expression increased cardiac electrical impulse conduction velocity and protected against thioridazine-induced QT prolongation. Patients positive for bipolar disorder CACNA1C genetic risk factors may have elevated proarrhythmic risk for adverse events in response to psychiatric medications that slow conduction or prolong the QT interval. This in vitro diagnostic tool enables cardiac testing specific to patients with psychiatric disorders to determine their sensitivity to off-target effects of psychiatric medications.

Premorbid intelligence quotient and school failure as risk markers for bipolar disorder and major depressive disorder

Mood disorders significantly impact global health, with MDD ranking as the second leading cause of disability in the United States and BD ranking 18th. Despite their prevalence and impact, the relationship between premorbid intelligence and the subsequent development of BD and MDD remains inconclusive.This study investigates the potential of premorbid Intelligence Quotient (IQ) and school failure frequency as risk factors for Bipolar Disorder (BD) and Major Depressive Disorder (MDD) in a birth cohort setting. We analyze data from the Pelotas population-based birth cohort study, comprising 3580 participants aged 22, who had no prior mood disorder diagnoses. Utilizing regression models and accounting for potential confounders, we assess the impact of IQ and school failure, measured at age 18, on the emergence of BD and MDD diagnoses at age 22, using individuals without mood disorders as comparators. Results reveal that lower IQ (below 70) at 18 is associated with an increased risk of BD (Adjusted Odds Ratio [AOR] 1.75, 95%CI: 1.00–3.09, p < 0.05), while higher IQ (above 120) is linked to MDD (AOR 2.16, 95%CI: 1.24–3.75, p < 0.001). Moreover, an elevated number of school failures is associated with increased BD risk (AOR 1.23, 95%CI: 1.11–1.41, p < 0.001), particularly for BD type 1 (AOR 1.36, 95% CI: 1.17–1.58, p < 0.001). These findings offer insights into the distinct premorbid intellectual characteristics of BD and MDD and contribute to a deeper understanding of their developmental trajectories, potentially informing the development of risk assessment tools for mood disorders.

Susceptibility and severity of COVID-19 and risk of psychiatric disorders in European populations: a Mendelian randomization study.

Observational studies have suggested that COVID-19 increases the prevalence of psychiatric disorders, but the results of such studies are inconsistent. This study aims to investigate the association between COVID-19 and the risk of psychiatric disorders using Mendelian randomization (MR) analysis. We used summary statistics from COVID-19 Host Genetics Initiative genome-wide association study (GWAS) of COVID-19 involving 2,586,691 participants from European ancestry. Genetic variations of five psychiatric disorders including autism spectrum disorder (ASD) (N = 46,351), bipolar disorder (BID) (N = 51,710), major depressive disorder (MDD) (N = 480,359), anxiety disorder (N = 83,566), and schizophrenia (SCZ) (N = 77,096) were extracted from several GWAS of European ancestry. The inverse-variance weighted (IVW) method as the main MR analysis conducted. We further performed sensitivity analyzes and heterogeneity analyzes as validation of primary MR results. The IVW analysis found that COVID-19 hospitalization phenotype was the risk factor for BID (OR = 1.320, 95% CI = 1.106-1.576, p = 0.002) and SCZ (OR = 1.096, 95% CI = 1.031-1.164, p = 0.002). Moreover, we detected a significant positive genetic correlation between COVID-19 severity and two psychiatric traits, BID (OR = 1.139, 95% CI = 1.033-1.256, p = 0.008) and SCZ (OR = 1.043, 95% CI = 1.005-1.082, p = 0.024). There was no evidence supporting the causal relationship between COVID-19 susceptibility and psychiatric disorders. Our results found that the COVID-19 hospitalization phenotype and COVID-19 severity phenotype might be the potential risks of BID and SCZ in European populations. Therefore, patients infected with SARS-CoV-2 should have enhanced monitoring of their mental status.

Prevention of Suicidal Behavior in Bipolar Disorder.

Excess mortality is a critical hallmark of bipolar disorder (BD) due to co-occurring general medical disorders and especially from suicide. It is timely to review of the status of suicide in BD and to consider the possibility of limiting suicidal risk. We carried out a semi-systematic review of recent research reports pertaining to suicide in BD. Suicide risk in BD is greater than with most other psychiatric disorders. Suicide rates (per 100,000/year) are approximately 11 and 4 in the adult and juvenile general populations, but over 200 in adults, and 100 among juveniles diagnosed with BD. Suicide attempt rates with BD are at least 20 times higher than in the adult general population, and over 50 times higher among juveniles. Notable suicidal risk factors in BD include: previous suicidal acts, depression, mixed-agitated-dysphoric moods, rapid mood-shifts, impulsivity, and co-occurring substance abuse. Suicide-preventing therapeutics for BD remain severely underdeveloped. Evidence favoring lithium treatment is stronger than for other measures, although encouraging findings are emerging for other treatments. Suicide is a leading clinical challenge for those caring for BD patients. Improved understanding of risk and protective factors combined with knowledge and close follow-up of BD patients should limit suicidal risk. Ethically appropriate and scientifically sound studies of plausible medicinal, physical, and psychosocial treatments aimed at suicide prevention specifically for BD patients are urgently needed.Reprinted from Bipolar Disord 2021; 23:14-23, with permission from John Wiley and Sons. Copyright © 2021.

Childhood trauma and its influence on the clinical features of bipolar disorder

BackgroundChildhood trauma is an environmental risk factor for bipolar disorder (BD), But its influence on the clinical features of BD has not been examined sufficiently. ObjectiveWe compared the childhood trauma between patients with BD and healthy controls (HCs) and determined how childhood trauma impacts clinical features, such as severity, mood episodes, and disease duration. Participants and settingThe study population comprised patients with BD (in a state of euthymia or depression, n = 90) and HCs (n = 94). MethodsThe Structured Clinical Interview for DSM-IV Axis I Disorders was used to diagnose BD and ascertain its clinical features. The Childhood Trauma Questionnaire (CTQ) was used to assess childhood trauma. ResultsThe total CTQ score and scores for the CTQ subscales emotional abuse, sexual abuse, emotional neglect, and physical neglect, significantly differed between the BD and HC groups. Emotional abuse was correlated with higher Hamilton Anxiety Rating Scale (HARS) score and more frequent mood episodes; emotional neglect was correlated with higher HARS score, longer disease duration, and more mood episodes; and total CTQ score was positively correlated with HARS score, disease duration, and mood episodes. Regression analysis showed that emotional neglect significantly predicted HARS score, Hamilton Depression Rating Scale score, and disease duration in the BD group (P < 0.05). ConclusionsPatients with BD have more serious childhood trauma. General childhood trauma, emotional abuse, and emotional neglect negatively affect the clinical features of BD.

Maximal Sensitivity to Child Maltreatment at the Ages of 6 and 11 Years is Associated with the Risk of Bipolar Disorder.

Adverse childhood experiences, including child maltreatment (CM), are relevant environmental risk factors for bipolar disorder (BD). However, little is known about the interaction of the type, duration and frequency of abuse with the timing of abuse in BD. The aim of this study was to investigate the different patterns of childhood trauma (frequency, type and chronology) between BD patients and healthy controls (HCs) and to identify BD-sensitive periods of exposure to CM that could influence functioning outcomes. The Maltreatment and Abuse Chronology Exposure (MACE) scale was used to evaluate the importance of the type and timing of maltreatment in a sample of 60 patients diagnosed with euthymic BD. Additionally, 76 HCs were recruited for comparison. All participants were of European-Caucasian origin and were assessed in the 2016-2019 period. To identify the variables that maximally differentiated the type and timing of exposure to CM between the BD and HC groups, a linear mixed effects model and random forest (RF) analyses were applied. We showed that multiplicity and severity, nonverbal emotional abuse, witnessing interparental violence and emotional neglect were the main factors associated with BD. In addition, regarding the occurrence of maltreatment in BD patients, we identified two sensitive periods with a principal peak at the age of 6 and a secondary peak at the age of 11. Functionality at the assessment time was associated with CM in adolescence for both HC and BD participants. Although the sample size and retrospective nature of the MACE instrument were the main limitations of our study, we were unable to explore the role of variables such as sex or socioeconomic status. We concluded that the multiplicity and sensitivity of CM exposure, mainly of the emotional type, during middle childhood are important risk factors for BD, at least in the European-Caucasian cultural setting.

Cross-Disorder Analysis of Genic and Regulatory Copy Number Variations in Bipolar Disorder, Schizophrenia, and Autism Spectrum Disorder

BackgroundWe aimed to determine the similarities and differences in the roles of genic and regulatory copy number variations (CNVs) in bipolar disorder (BD), schizophrenia (SCZ), and autism spectrum disorder (ASD). MethodsBased on high-resolution CNV data from 8708 Japanese samples, we performed to our knowledge the largest cross-disorder analysis of genic and regulatory CNVs in BD, SCZ, and ASD. ResultsIn genic CNVs, we found an increased burden of smaller (<100 kb) exonic deletions in BD, which contrasted with the highest burden of larger (>500 kb) exonic CNVs in SCZ/ASD. Pathogenic CNVs linked to neurodevelopmental disorders were significantly associated with the risk for each disorder, but BD and SCZ/ASD differed in terms of the effect size (smaller in BD) and subtype distribution of CNVs linked to neurodevelopmental disorders. We identified 3 synaptic genes (DLG2, PCDH15, and ASTN2) as risk factors for BD. Whereas gene set analysis showed that BD-associated pathways were restricted to chromatin biology, SCZ and ASD involved more extensive and similar pathways. Nevertheless, a correlation analysis of gene set results indicated weak but significant pathway similarities between BD and SCZ or ASD (r = 0.25–0.31). In SCZ and ASD, but not BD, CNVs were significantly enriched in enhancers and promoters in brain tissue. ConclusionsBD and SCZ/ASD differ in terms of CNV burden, characteristics of CNVs linked to neurodevelopmental disorders, and regulatory CNVs. On the other hand, they have shared molecular mechanisms, including chromatin biology. The BD risk genes identified here could provide insight into the pathogenesis of BD.

Pregnant women with bipolar disorder who have a history of childhood maltreatment: Intergenerational effects of trauma on fetal neurodevelopment and birth outcomes.

Intergenerational transmission of trauma occurs when the effects of childhood maltreatment (CM) influence the next generation's development and health; prenatal programming via maternal mood symptoms is a potential pathway. CM is a risk factor for bipolar disorder which is present in 1.8% of pregnant women. Mood symptoms are likely to increase during pregnancy, particularly for those with a history of CM. We examined whether there was evidence for intergenerational transmission of trauma in utero in this population, and whether maternal mood was a transmission pathway. CM and maternal mood were self-reported by N=82 pregnant women in treatment for bipolar disorder. Fetal heart rate variability (FHRV) was measured at 24, 30, and 36 weeks' gestation. Gestational age at birth and birth weight were obtained from medical charts. A cluster analysis yielded two groups, Symptom+ (18.29%) and Euthymic (81.71%), who differed on severe mood symptoms (p < 0.001) but not on medication use. The Symptom+ group had more CM exposures (p < 0.001), a trend of lower FHRV (p=0.077), and greater birth complications (33.3% vs. 6.07% born preterm p < 0.01). Maternal prenatal mood mediated the association between maternal CM and birth weight in both sexes and at trend level for gestational age at birth in females. This is the first study to identify intergenerational effects of maternal CM prior to postnatal influences in a sample of pregnant women with bipolar disorder. These findings underscore the potential enduring impact of CM for women with severe psychiatric illness and their children.

Resting-state functional connectivity graph-properties correlate with bipolar disorder-risk in young medication-free depressed subjects: Bipolar-risk Resting State Functional Connectivity in Major Depression

BackgroundMajor Depressive Disorder (MDD) is frequently associated with risk factors for the development of Bipolar Disorder (BD). Using graph theory, we investigated brain network properties associated with BD risk factors in young MDD subjects. MethodsResting-state fMRI was acquired from a large cohort (N= 104) of medication-free currently depressed participants (25 BD depression (BDD), 79 MDD). Lifetime mania symptom count (LMSC), current Young Mania Rating Scale (YMRS) score, and family history of mood disorders (FHMD) were examined as BD risk factors. Functional connectivity matrices from 280 regions of interests (ROIs) were first entered into the Network Based Statistic (NBS) toolbox to identify connections that varied with each risk factor. Next, within the correlated network for each risk factor, global and nodal graph properties for the top five linked nodes were calculated. Last, using identified graph properties, machine learning classification (MLC) between BDD, MDD with BD risk factors (MDD+), and without BD risk factors (MDD-) was conducted. ResultsLMSC positively correlated with left lateral orbitofrontal cortex (LOFC) Communication Efficiency and with left middle temporal Eigenvector Centrality. Current YMRS score positively correlated with right amygdala Communication Efficiency and Closeness Centrality. FHMD positively correlated with right insula Eigenvector Centrality. Acceptable MLC accuracy was seen between BDD and MDD- using middle temporal Eigenvector Centrality, whereas moderate accuracy was seen between MDD+ and MDD- using OFC Communication Efficiency. LimitationAlthough participants were medication-free, they were not medication-naïve. ConclusionFunctional connectome graph properties may serve as BD vulnerability biomarkers in young individuals with MDD.

Development and validation of a risk calculator for major mood disorders among the offspring of bipolar parents using information collected in routine clinical practice.

BackgroundFamily history is a significant risk factor for bipolar disorders (BD), but the magnitude of risk varies considerably between individuals within and across families. Accurate risk estimation may increase motivation to reduce modifiable risk exposures and identify individuals appropriate for monitoring over the peak risk period. Our objective was to develop and independently replicate an individual risk calculator for bipolar spectrum disorders among the offspring of BD parents using data collected in routine clinical practice.MethodsData from the longitudinal Canadian High-Risk Offspring cohort study collected from 1996 to 2020 informed the development of a 5 and 10-year risk calculator using parametric time-to-event models with a cure fraction and a generalized gamma distribution. The calculator was then externally validated using data from the Lausanne–Geneva High-Risk Offspring cohort study collected from 1996 to 2020. A time-varying C-index by age in years was used to estimate the probability that the model correctly classified risk. Bias corrected estimates and 95% confidence limits were derived using a jackknife resampling approach.FindingsThe primary outcome was age of onset of a major mood disorder. The risk calculator was most accurate at classifying risk in mid to late adolescence in the Canadian cohort (n = 285), and a similar pattern was replicated in the Swiss cohort (n = 128). Specifically, the time-varying C-index indicated that there was approximately a 70% chance that the model would correctly predict which of two 15-year-olds would be more likely to develop the outcome in the future. External validation within a smaller Swiss cohort showed mixed results.InterpretationFindings suggest that this model may be a useful clinical tool in routine practice for improved individualized risk estimation of bipolar spectrum disorders among the adolescent offspring of a BD parent; however, risk estimation in younger high-risk offspring is less accurate, perhaps reflecting the evolving nature of psychopathology in early childhood. Based on external validation with a Swiss cohort, the risk calculator may not be as predictive in more heterogenous high-risk populations.FundingThe Canadian High-Risk Study has been funded by consecutive operating grants from the Canadian Institutes for Health Research, currently CIHR PJT Grant 152796 he Lausanne-Geneva high-risk study was and is supported by five grants from the Swiss National Foundation (#3200–040,677, #32003B-105,969, #32003B-118,326, #3200–049,746 and #3200–061,974), three grants from the Swiss National Foundation for the National Centres of Competence in Research project “The Synaptic Bases of Mental Diseases” (#125,759, #158,776, and #51NF40 – 185,897), and a grant from GlaxoSmithKline Clinical Genetics.

Détection et intervention précoce auprès des jeunes avec trouble bipolaire émergent : où en sommes-nous ?

Bipolar disorder (BD) is one of the most disabling chronic illness for which the delay in diagnosis and access to adequate care is about 10 years, with many consequences such as numerous comorbidities, greater illness severity and resistance to treatments. Building on advances in early intervention in psychosis, optimizing the detection of patients with BD and intervening early is essential to improve their prognosis. Identifying risk factors for BD would allow earlier detection of the target population with the aims of: (1) preventing the development of the disease, (2) delaying its onset and (3) improving the course through more timely treatment. We conducted a narrative review of the literature of the past 30 years on risk factors of BD and synthetising the concepts of at-risk of BD mental state, the staging model and associated interventions. These concepts are illustrated by a clinical case with and without early intervention highlighting the challenges of early intervention in BD and the scientific data currently available of use to the clinician (both general practitioners and psychiatrist). In addition to genetic and environmental risk factors (early trauma, substance use, etc.), vulnerability markers (cyclothymic or hyperthymic temperament, cluster B personality disorder) can guide the clinician towards the detection of at risk of BD mental state syndrome consisting of attenuated symptoms of hypomania, mood lability, early depressive episode with psychotic, severe or atypical characteristics. The delay in access to care attributable to the absence of “help-seeking”, to self-stigmatization, or to unrecognized diagnoses (misdiagnosis with personality disorders or substance use disorders) weighs down the prognosis leading, as episodes cumulate over time, to incomplete remission of episodes with residual symptoms and significant functional decline. The use of validated tools and careful coordination of the various actors are assets for the early identification of subjects at-risk of transition to BD. Following the staging model, targeted primary prevention interventions (e.g., promotion of good sleep hygiene, stress management strategies) for at-risk individuals should be offered by general practitioner or other front-line mental health professionals (e.g., psychologist, nurse); early secondary prevention (for stage 1) should be provided by general psychiatric or general medicine services. Although no official guidelines for early intervention for BD are available yet, experts opinions are multiplying and supporting an integrated approach that maximizes young patient engagement. These integrated approaches aiming at symptomatic and functional improvement combine effective psychopharmacology and psychosocial interventions, including cognitive- behavioral therapy, approaches based on social rhythm, psychoeducation, relapse prevention, social and vocational recovery and family interventions. The scarcity of studies on the early stages of bipolar disorder limits the predictive value of risk factors and at-risk syndromes which remain to be validated. Prospective controlled studies are warranted to improve the prevention efforts and effective early treatment of bipolar disorder.

Environmental Risk Factors for Schizophrenia and Bipolar Disorder and Their Relationship to Genetic Risk: Current Knowledge and Future Directions.

Schizophrenia (SZ) and bipolar disorder (BD) are severe psychiatric disorders which result from complex interplay between genetic and environmental factors. It is well-established that they are highly heritable disorders, and considerable progress has been made identifying their shared and distinct genetic risk factors. However, the 15–40% of risk that is derived from environmental sources is less definitively known. Environmental factors that have been repeatedly investigated and often associated with SZ include: obstetric complications, infections, winter or spring birth, migration, urban living, childhood adversity, and cannabis use. There is evidence that childhood adversity and some types of infections are also associated with BD. Evidence for other risk factors in BD is weaker due to fewer studies and often smaller sample sizes. Relatively few environmental exposures have ever been examined for SZ or BD, and additional ones likely remain to be discovered. A complete picture of how genetic and environmental risk factors confer risk for these disorders requires an understanding of how they interact. Early gene-by-environment interaction studies for both SZ and BD often involved candidate genes and were underpowered. Larger samples with genome-wide data and polygenic risk scores now offer enhanced prospects to reveal genetic interactions with environmental exposures that contribute to risk for these disorders. Overall, although some environmental risk factors have been identified for SZ, few have been for BD, and the extent to which these account for the total risk from environmental sources remains unknown. For both disorders, interactions between genetic and environmental risk factors are also not well understood and merit further investigation. Questions remain regarding the mechanisms by which risk factors exert their effects, and the ways in which environmental factors differ by sex. Concurrent investigations of environmental and genetic risk factors in SZ and BD are needed as we work toward a more comprehensive understanding of the ways in which these disorders arise.

For whom the circadian clock ticks? Investigation of PERIOD and CLOCK gene variants in bipolar disorder

ABSTRACT Clock genes play significant roles in the regulation of circadian rhythms, which are thought to be involved in the pathophysiology of neurodegenerative and psychiatric diseases. We aimed to investigate the association of five gene polymorphisms (PER3 VNTR (rs57875989), PER2 rs2304672, CLOCK rs1801260, CLOCK rs10462028, CLOCK rs11932595) with PCR-based methods as potential risk factors in bipolar disorder (BD). We used a multiple testing methodology in BD patients (n = 121) and healthy control individuals (n = 121) of Turkish descent to analyze the effects of these gene variants both as risk factors for the disorder and for the evaluation of these variants in the patient group with multiple subscales. We evaluated the circadian rhythm disturbances and seasonal variations in mood and behavior in BD patients using the Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) and Seasonal Pattern Assessment Questionnaire (SPAQ) to enlighten the possible links between these scores and the studied circadian gene variants. The results of our study revealed significant associations: PER3 VNTR (rs57875989) 5/5 repeat genotype displayed a protective effect against BD when compared with 4/4 repeat genotype. Moreover, patients with PER3 VNTR 5/5 repeat genotype displayed a higher ratio of hypomania. PER2 rs2304672 G allele frequency increased the risk for BD. There was no association in terms of genotype/allele frequency comparisons between patients and controls for CLOCK gene variants. However, significant associations were found in patients in terms of clinical and behavioral patterns such as mean age at disease onset and BRIAN total scores enabling some risk stratifications for patients. Our results indicate the significance of circadian gene variants in BD, which need to be confirmed in different studies with larger samples. Thus, the possible endophenotypes of BD can be enlightened and advanced chronotherapeutics approaches can be manipulated in the future for clinical benefit.