Risk factors in relation to an emergence of bipolar disorder: a systematic review

Factors that influence participation in physical activity for people with bipolar disorder: a synthesis of qualitative evidence

BACKGROUND

Mental health problems contribute significantly to the overall disease burden worldwide and are major causes of disability, suicide, and ischaemic heart disease. People with bipolar disorder report lower levels of physical activity than the general population, and are at greater risk of chronic health conditions including cardiovascular disease and obesity. These contribute to poor health outcomes. Physical activity has the potential to improve quality of life and physical and mental well-being.

OBJECTIVES

To identify the factors that influence participation in physical activity for people diagnosed with bipolar disorder from the perspectives of service users, carers, service providers, and practitioners to help inform the design and implementation of interventions that promote physical activity.

SEARCH METHODS

We searched MEDLINE, PsycINFO, and eight other databases to March 2021. We also contacted experts in the field, searched the grey literature, and carried out reference checking and citation searching to identify additional studies. There were no language restrictions.

SELECTION CRITERIA

We included qualitative studies and mixed-methods studies with an identifiable qualitative component. We included studies that focused on the experiences and attitudes of service users, carers, service providers, and healthcare professionals towards physical activity for bipolar disorder.

DATA COLLECTION AND ANALYSIS

We extracted data using a data extraction form designed for this review. We assessed methodological limitations using a list of predefined questions. We used the "best fit" framework synthesis based on a revised version of the Health Belief Model to analyse and present the evidence. We assessed methodological limitations using the CASP Qualitative Checklist. We used the GRADE-CERQual (Confidence in the Evidence from Reviews of Qualitative research) guidance to assess our confidence in each finding. We examined each finding to identify factors to inform the practice of health and care professionals and the design and development of physical activity interventions for people with bipolar disorder.

MAIN RESULTS

We included 12 studies involving a total of 592 participants (422 participants who contributed qualitative data to an online survey, 170 participants in qualitative research studies). Most studies explored the views and experiences of physical activity of people with experience of bipolar disorder. A number of studies also reported on personal experiences of physical activity components of lifestyle interventions. One study included views from family carers and clinicians. The majority of studies were from high-income countries, with only one study conducted in a middle-income country. Most participants were described as stable and had been living with a diagnosis of bipolar disorder for a number of years. We downgraded our confidence in several of the findings from high confidence to moderate or low confidence, as some findings were based on only small amounts of data, and the findings were based on studies from only a few countries, questioning the relevance of these findings to other settings. We also had very few perspectives of family members, other carers, or health professionals supporting people with bipolar disorder. The studies did not include any findings from service providers about their perspectives on supporting this aspect of care. There were a number of factors that limited people's ability to undertake physical activity. Shame and stigma about one's physical appearance and mental health diagnosis were discussed. Some people felt their sporting skills/competencies had been lost when they left school. Those who had been able to maintain exercise through the transition into adulthood appeared to be more likely to include physical activity in their regular routine. Physical health limits and comorbid health conditions limited activity. This included bipolar medication, being overweight, smoking, alcohol use, poor diet and sleep, and these barriers were linked to negative coping skills. Practical problems included affordability, accessibility, transport links, and the weather. Workplace or health schemes that offered discounts were viewed positively. The lack of opportunity for exercise within inpatient mental health settings was a problem. Facilitating factors included being psychologically stable and ready to adopt new lifestyle behaviours. There were positive benefits of being active outdoors and connecting with nature. Achieving balance, rhythm, and routine helped to support mood management. Fitting physical activity into a regular routine despite fluctuating mood or motivation appeared to be beneficial if practised at the right intensity and pace. Over- or under-exercising could be counterproductive and accelerate depressive or manic moods. Physical activity also helped to provide a structure to people's daily routines and could lead to other positive lifestyle benefits. Monitoring physical or other activities could be an effective way to identify potential triggers or early warning signs. Technology was helpful for some. People who had researched bipolar disorder and had developed a better understanding of the condition showed greater confidence in managing their care or providing care to others. Social support from friends/family or health professionals was an enabling factor, as was finding the right type of exercise, which for many people was walking. Other benefits included making social connections, weight loss, improved quality of life, and better mood regulation. Few people had been told of the benefits of physical activity. Better education and training of health professionals could support a more holistic approach to physical and mental well-being. Involving mental health professionals in the multidisciplinary delivery of physical activity interventions could be beneficial and improve care. Clear guidelines could help people to initiate and incorporate lifestyle changes.

AUTHORS' CONCLUSIONS

There is very little research focusing on factors that influence participation in physical activity in bipolar disorder. The studies we identified suggest that men and women with bipolar disorder face a range of obstacles and challenges to being active. The evidence also suggests that there are effective ways to promote managed physical activity. The research highlighted the important role that health and care settings, and professionals, can play in assessing individuals' physical health needs and how healthy lifestyles may be promoted. Based on these findings, we have provided a summary of key elements to consider for developing physical activity interventions for bipolar disorder.

Risk and protective factors for severe mental disorders in Asia

Among 369 diseases and injuries, the years lived with disability (YLDs) and disability-adjusted life-years (DALYs) rates for severe mental illnesses (SMIs) are within the top 20 %. Research on risk and protective factors for SMIs is critically important, as acting on modifiable factors may reduce their incidence or postpone their onset, while early detection of new cases enables prompt treatment and improves prognosis. However, as most of the studies on these factors are from Western countries, the findings are not generalizable across ethnic groups. This led us to conduct a systematic review of the risk and protective factors for SMIs identified in Asian studies. There were common factors in Asian and Western studies and unique factors in Asian studies. In-depth knowledge of these factors could help reduce disability, and the economic and emotional burden of SMIs. We hope that this review will inform future research and policy-making on mental health in Asian countries.

Prenatal infection and adolescent social adversity affect microglia, synaptic density, and behavior in male rats

Maternal infection during pregnancy and childhood social trauma have been associated with neurodevelopmental and affective disorders, such as schizophrenia, autism spectrum disorders, bipolar disorder and depression. These disorders are characterized by changes in microglial cells, which play a notable role in synaptic pruning, and synaptic deficits. Here, we investigated the effect of prenatal infection and social adversity during adolescence - either alone or in combination - on behavior, microglia, and synaptic density. Male offspring of pregnant rats injected with poly I:C, mimicking prenatal infection, were exposed to repeated social defeat during adolescence. We found that maternal infection during pregnancy prevented the reduction in social behavior and increase in anxiety induced by social adversity during adolescence. Furthermore, maternal infection and social adversity, alone or in combination, induced hyperlocomotion in adulthood. Longitudinal in vivo imaging with [11C]PBR28 positron emission tomography revealed that prenatal infection alone and social adversity during adolescence alone induced a transient increase in translocator protein TSPO density, an indicator of glial reactivity, whereas their combination induced a long-lasting increase that remained until adulthood. Furthermore, only the combination of prenatal infection and social adversity during adolescence induced an increase in microglial cell density in the frontal cortex. Prenatal infection increased proinflammatory cytokine IL-1β protein levels in hippocampus and social adversity reduced anti-inflammatory cytokine IL-10 protein levels in hippocampus during adulthood. This reduction in IL-10 was prevented if rats were previously exposed to prenatal infection. Adult offspring exposed to prenatal infection or adolescent social adversity had a higher synaptic density in the frontal cortex, but not hippocampus, as evaluated by synaptophysin density. Interestingly, such an increase in synaptic density was not observed in rats exposed to the combination of prenatal infection and social adversity, perhaps due to the long-lasting increase in microglial density, which may lead to an increase in microglial synaptic pruning. These findings suggest that changes in microglia activity and cytokine release induced by prenatal infection and social adversity during adolescence may be related to a reduced synaptic pruning, resulting in a higher synaptic density and behavioral changes in adulthood.

Help-seeking patterns and level of care for individuals with bipolar disorder in Rwanda

Most descriptive data on individuals with bipolar disorder originate from high-resource settings. Very little is known about the accessibility and service provision of intensive mental health care to persons living with bipolar disorder in low-resource settings. This information is needed to inform health systems and guide practitioners to improve standard treatment options and access to treatment. This cross-sectional study explored the level of care for outpatients with bipolar disorder and their help-seeking patterns at the two national referral hospitals in Rwanda. The study found that the majority, 93%, of outpatients with bipolar disorder in Rwanda were on prophylactic psychopharmacological treatment, but mainly first-generation antipsychotics and just 3% received lithium treatment. Furthermore, there was a lack of psychosocial intervention; consequently, 44% were not aware that they had bipolar disorder. Moreover, 1 in 5 participants utilized or had previously used traditional medicine. Awareness of own diagnostic status was not associated with educational level or use of traditional medicine. The study's sample size of 154 patients is relatively small, and the cross-sectional design does not provide causal inferences. The results demonstrate a considerable unmet need for improved mental health care services for individuals with bipolar disorder in Rwanda, including access to optimal medication and psychosocial interventions. Psychoeducation could be a possible starting point for improving the standard of care, informing the individual on their diagnosis and medication while empowering them to engage in their treatment plan. Trial registration: ClinicalTrials.gov NCT04671225. Registered on November 2020.

Maternal infection during pregnancy aggravates the behavioral response to an immune challenge during adolescence in female rats

Prenatal and early postnatal infection have been associated with changes in microglial activity and the development of psychiatric disorders. Here, we investigated the effect of prenatal immune activation and postnatal immune challenge, alone and combined, on behavior and microglial cell density in female Wistar rats. Pregnant rats were injected with poly I:C to induce a maternal immune activation (MIA). Their female offspring were subsequently exposed to a lipopolysaccharide (LPS) immune challenge during adolescence. Anhedonia, social behavior, anxiety, locomotion, and working memory were measured with the sucrose preference, social interaction, open field, elevated-plus maze, and Y-maze test, respectively. Microglia cell density was quantified by counting the number of Iba-1 positive cells in the brain cortex. Female MIA offspring were more susceptible to the LPS immune challenge during adolescence than control offspring as demonstrated by a more pronounced reduction in sucrose preference and body weight on the days following the LPS immune challenge. Furthermore, only the rats exposed to both MIA and LPS showed long-lasting changes in social behavior and locomotion. Conversely, the combination MIA and LPS prevented the anxiety induced by MIA alone during adulthood. MIA, LPS, or their combination did not change microglial cell density in the parietal and frontal cortex of adult rats. The results of our study suggest that the maternal immune activation during pregnancy aggravates the response to an immune challenge during adolescence in female rats.

Epigenetic age deacceleration in youth at familial risk for schizophrenia and bipolar disorder

Epigenetic modifications occur sequentially during the lifespan, but their pace can be altered by external stimuli. The onset of schizophrenia and bipolar disorder is critically modulated by stressors that may alter the epigenetic pattern, a putative signature marker of exposure to environmental risk factors. In this study, we estimated the age-related epigenetic modifications to assess the differences between young individuals at familial high risk (FHR) and controls and their association with environmental stressors. The sample included 117 individuals (6-17 years) at FHR (45%) and a control group (55%). Blood and saliva samples were used estimate the epigenetic age with six epigenetic clocks through methylation data. Environmental risk was measured with obstetric complications, socioeconomic statuses and recent stressful life events data. Epigenetic age was correlated with chronological age. FHR individuals showed epigenetic age deacceleration of Horvath and Hannum epigenetic clocks compared to controls. No effect of the environmental risk factors on the epigenetic age acceleration could be detected. Epigenetic age acceleration adjusted by cell counts showed that the FHR group was deaccelerated also with the PedBE epigenetic clock. Epigenetic age asynchronicities were found in the young at high risk, suggesting that offspring of affected parents follow a slower pace of biological aging than the control group. It still remains unclear which environmental stressors orchestrate the changes in the methylation pattern. Further studies are needed to better characterize the molecular impact of environmental stressors before illness onset, which could be critical in the development of tools for personalized psychiatry.

Impact of Early-Life Factors on Risk for Schizophrenia and Bipolar Disorder

BACKGROUND AND HYPOTHESIS

Schizophrenia (SCZ) and bipolar disorder (BD) have shared genetic risk and clinical symptoms, yet the extent to which environmental risk factors are shared is not well known. We aimed to examine the associations of early-life environmental exposures with the risk of SCZ and BD.

STUDY DESIGN

We conducted a Swedish register-based nested case-control study using 4184 SCZ and 18 681 BD cases diagnosed 1988-2013, individually matched to 5 population-based controls by birth year, sex and birthplace. Conditional logistic regression was used to evaluate the risk of SCZ and BD by seasonality, severe prenatal infections, and perinatal factors.

STUDY RESULTS

Seasonality had similar patterns of risk for both disorders: Higher risk for births November-December; lower risk April-June. Experiencing any perinatal factor was associated with a significantly higher risk of SCZ (incidence rate ratio [IRR] 1.19, 95%CI 1.11-1.63) and to a lesser extent BD (IRR 1.08, 95%CI 1.05-1.12). Prenatal infections were only associated with a greater risk of SCZ (IRR 1.30, 95%CI 1.04-1.63). In the mutually adjusted model, only perinatal factors were associated with outcomes. Several perinatal factors were associated with both disorders, but estimates were significantly higher for SCZ for low birth weight, low APGAR, and high parity. Congenital malformations were only associated with risk of SCZ, and jaundice with BD.

CONCLUSIONS

Adverse perinatal factors and winter birth were the risk factors for both disorders, while severe prenatal infections were only risk a factor for SCZ. Early-life exposures were associated with a higher risk of both disorders, but may play a larger role in the development of SCZ than BD.

Course of subthreshold manic symptoms and related risk factors in the general population: A three-year follow-up study

OBJECTIVES

Subthreshold manic symptoms (subM) are a risk factor for the onset and recurrence of bipolar disorder (BD). Individuals with subM may benefit from preventive interventions, however, their development is hampered by a lack of knowledge on subM prevalence and subsequent course. This study examines subM characteristics, course, and risk factors for an unfavourable course.

METHODS

In a Dutch representative, population-based sample aged 18-64 (N = 4618), we assessed subM, defined as the occurrence of manic core symptoms (elation/irritability), without meeting full DSM-IV criteria for BD I or II in the past 3 years. Comparison groups had either no manic symptoms (noM) or hypomania/mania in the context of BD (mBD) in the past 3 years. Furthermore, we differentiated a mild and moderate type of subM, based on the number of manic symptoms. A subsequent three-year course was assessed prospectively.

RESULTS

SubM had a three-year prevalence of 4.9%. Its prevalence, characteristics, and course were in between noM and mBD, and there were few differences between mild and moderate subM. Over the 3-year follow-up, 25.0% of individuals with subM had persistent subM and another 6.1% transitioned to mBD. Eleven significant risk factors for this unfavourable course were found. The most important were a history of depression/dysthymia (OR 3.75, p ≤ 0.001), living alone (OR 2.61, p ≤ 0.01) and elevated neuroticism score (OR 1.21, p ≤ 0.001).

CONCLUSIONS

This study supports the validity and clinical relevance of subM as a BD prodrome. It demonstrates that subM symptoms often persist or increase during follow-up and identifies 11 risk factors that are associated with an unfavourable course.

Psychiatric disorders among employment requiring firearms

Individuals who carry guns as a requirement of employment frequently experience hazards that can be stress inducing, violent, traumatizing, or cause personal injury. This study used data from the Collaborative Psychiatric Epidemiological Surveys (CPES; n = 20,013), to examine mental health diagnoses of individuals that ever worked at a job requiring a firearm. Consistent with existing literature, the findings indicated that those who worked in professions requiring a firearm showed similar risk of mental health diagnoses as law enforcement officers which includes symptoms of trauma, mood disorders, and alcohol use. Further, race/ethnic differences emerged in patterns of mental health diagnoses, suggesting sociocultural differences influence diagnoses. These findings indicate the necessity for further investigation of the understudied area of mental health of those within employment positions that require firearms.

Prenatal and perinatal risk factors for bipolar disorder: A systematic review and meta-analysis

BACKGROUND

Perinatal and prenatal risk factors may be implicated in the development of bipolar disorder, but literature lacks a comprehensive account of possible associations.

METHODS

We performed a systematic review and meta-analyses of observational studies detailing the association between prenatal and perinatal risk factors and bipolar disorder in adulthood by searching PubMed, Embase, Web of Science and Psycinfo for articles published in any language between January 1st, 1960 and September 20th, 2021. Meta-analyses were performed when risk factors were available in at least two studies.

FINDINGS

Twenty seven studies were included with 18 prenatal or perinatal factors reported across the literature. Peripartum asphyxia (k = 5, OR = 1.46 [1.02; 2.11]), maternal stress during pregnancy (k = 2, OR = 12.00 [3.30; 43.59]), obstetric complications (k = 6, OR = 1.41 [1.18; 1.69]), and birth weight less than 2500 g (k = 5, OR = 1.28 [1.04; 1.56]) were associated with an increased risk for bipolar disorder.

INTERPRETATION

Perinatal and prenatal risk factors are implicated in the pathogenesis of bipolar disorder, supporting a role of prenatal care in preventing the condition.

Schizophrenia, Bipolar and Major Depressive Disorders: Overview of Clinical Features, Neurotransmitter Alterations, Pharmacological Interventions, and Impact of Oxidative Stress in the Disease Process

Psychiatric disorders are one of the leading causes of disability worldwide and affect the quality of life of both individuals and the society. The current understanding of these disorders points toward receptor dysfunction and neurotransmitter imbalances in the brain. Treatment protocols are hence oriented toward normalizing these imbalances and ameliorating the symptoms. However, recent literature has indicated the possible role of depleted levels of antioxidants like glutathione (GSH) as well as an alteration in the levels of the pro-oxidant, iron in the pathogenesis of major psychiatric diseases, viz., schizophrenia (Sz), bipolar disorder (BD), and major depressive disorder (MDD). This review aims to highlight the involvement of oxidative stress (OS) in these psychiatric disorders. An overview of the clinical features, neurotransmitter abnormalities, and pharmacological treatments concerning these psychiatric disorders has also been presented. Furthermore, it attempts to synthesize literature from existing magnetic resonance spectroscopy (MRS) and quantitative susceptibility mapping (QSM) studies for these disorders, assessing GSH and iron, respectively. This manuscript is a sincere attempt to stimulate research discussion to advance the knowledge base for further understanding of the pathoetiology of Sz, BD, and MDD.

Stress exposure and well-being: correlates of meeting criteria for bipolar disorder, borderline personality disorder, or both

PURPOSE

Bipolar and borderline personality disorders share similar features, are challenging to differentiate and sometimes co-occur in the same individual. This paper compares people with bipolar, borderline, both or neither, analyzing sociodemographic characteristics, lifetime exposure to stressors, and emotional, social, and physical wellbeing to illuminate differences in life experiences associated with expressing symptoms consistent with bipolar, borderline, or both.

METHODS

Data were analyzed from the 2012-13 National Epidemiological Survey on Alcohol and Related Conditions (NESARC-III), N = 36,309. Survey participants were classified as bipolar (N = 488, 1.3%), borderline (N = 1758, 4.8%), both (N = 388, 1.1%), or neither (N = 33,675, 92.8%). Differences between these groups regarding demographics, adverse childhood experiences, recent stressors, lifetime trauma, psychiatric co-morbidities, and emotional, social, and physical wellbeing were assessed with the adjusted Wald F test.

RESULTS

People with bipolar were more likely to also have borderline (44.3%) than the reverse (18.1%). People with both disorders were least advantaged socioeconomically, most exposed to stressors and traumas across the life course, and had the worst wellbeing emotionally, socially, and physically. Differences between people with both disorders vs. borderline only were smaller than between people with borderline vs. bipolar, although bipolar disorder was associated with considerable hardship relative to having neither disorder.

CONCLUSION

Borderline personality disorder alone or in combination with bipolar is associated with worse economic, social, and health outcomes than bipolar alone. Borderline can resolve with evidence-based treatment, and it is critical to correctly differentiate between the two conditions, so people with borderline and/or bipolar have the optimum chance for recovery.

Is early exposure to cannabis associated with bipolar disorder? Results from a Finnish birth cohort study

BACKGROUND AND AIMS

There are few longitudinal studies assessing the association of cannabis use and subsequent onset of bipolar disorder. We aimed to measure the association between early cannabis exposure and subsequent bipolar disorder.

DESIGN, SETTING AND PARTICIPANTS

Observational study linking a sample from the northern Finland birth cohort 1986 (n = 6325) to nation-wide register data to examine the association of life-time cannabis exposure at age 15/16 years and subsequent bipolar disorder until age 33 (until the end of 2018); 6325 individuals (48.8% males) were included in the analysis.

MEASUREMENTS

Cannabis exposure was measured via self-report. Bipolar disorder was measured via bipolar disorder-related diagnostic codes (ICD-10: F30.xx, F31.xx) collected from the Care Register for Health Care 2001-18, the Register of Primary Health Care Visits 2011-18, the medication reimbursement register of the Social Insurance Institution of Finland 2001-05 and the disability pensions of the Finnish Center for Pensions 2001-16. Potential confounders included demographic characteristics, parental psychiatric disorders, emotional and behavioral problems and other substance use.

FINDINGS

Three hundred and fifty-two adolescents (5.6%) reported any cannabis use until the age of 15-16 years. Of the whole sample, 66 (1.0%) were diagnosed with bipolar disorder. Adolescent cannabis use was associated with bipolar disorder [hazard ratio (HR) = 3.46; 95% confidence interval (CI) = 1.81-6.61]. This association remained statistically significant after adjusting for sex, family structure and parental psychiatric disorders (HR = 3.00; 95% CI = 1.47-6.13) and after further adjusting for adolescent emotional and behavioral problems (HR = 2.34; 95% CI = 1.11-4.94). Further adjustments for frequent alcohol intoxications, daily smoking and lifetime illicit drug use attenuated the associations to statistically non-significant.

CONCLUSIONS

In Finland, the positive association between early cannabis exposure and subsequent development of bipolar disorder appears to be confounded by other substance use.

Psychosocial markers of age at onset in bipolar disorder: a machine learning approach

BACKGROUND

Bipolar disorder is a chronic and severe mental health disorder. Early stratification of individuals into subgroups based on age at onset (AAO) has the potential to inform diagnosis and early intervention. Yet, the psychosocial predictors associated with AAO are unknown.

AIMS

We aim to identify psychosocial factors associated with bipolar disorder AAO.

METHOD

Using data from the Bipolar Disorder Research Network UK, we employed least absolute shrinkage and selection operator regression to identify psychosocial factors associated with bipolar disorder AAO. Twenty-eight factors were entered into our model, with AAO as our outcome measure.

RESULTS

We included 1022 participants with bipolar disorder (μ = 23.0, s.d. ± 9.86) in our model. Six variables predicted an earlier AAO: childhood abuse (β = -0.2855), regular cannabis use in the year before onset (β = -0.2765), death of a close family friend or relative in the 6 months before onset (β = -0.2435), family history of suicide (β = -0.1385), schizotypal personality traits (β = -0.1055) and irritable temperament (β = -0.0685). Five predicted a later AAO: the average number of alcohol units consumed per week in the year before onset (β = 0.1385); birth of a child in the 6 months before onset (β = 0.2755); death of parent, partner, child or sibling in the 6 months before onset (β = 0.3125); seeking work without success for 1 month or more in the 6 months before onset (β = 0.3505) and a major financial crisis in the 6 months before onset (β = 0.4575).

CONCLUSIONS

The identified predictor variables have the potential to help stratify high-risk individuals into likely AAO groups, to inform treatment provision and early intervention.

Gender disparity in bipolar disorder diagnosis in the United States: A retrospective analysis of the 2005-2017 MarketScan Commercial Claims database

OBJECTIVE

To examine gender disparities in the diagnosis of bipolar disorder (BD) within a privately insured population in the United States and investigate potential contributing factors for these gender differences.

METHODS

This retrospective cohort study utilized 2005-2017 claims data from the MarketScan^® Commercial Claims and Encounters database. The study cohort included subjects, aged 10-64 years, who had a minimum of 1-year continuous insurance coverage and no record of a BD diagnosis before cohort entry. We examined the gender difference in BD diagnosis rate, overall and by subgroups. We then used Cox regression models to evaluate the gender effect on time to first BD diagnosis, and the potential moderators of gender effect.

RESULTS

The study cohort consisted of 97,193,443 subjects; 0.45% of subjects were diagnosed with BDs after cohort entry with males having a lower diagnosis rate than females (0.36% vs. 0.54%). The Cox regression analysis indicated that males were less likely to be diagnosed with BDs (unadjusted Hazard Ratio, HR [95% CI]: 0.69 [0.68-0.69]) and gender difference remained significant after adjusting for demographics, comorbidity and healthcare utilizations (adjusted HR [95% CI]: 0.77 [0.76-0.77]). Gender disparity was consistently strong among most age groups, but varied in other demographic subgroups.

CONCLUSIONS

Even though the prevalence of BDs is approximately equal between genders in the general population, our study found a much lower diagnosis rate in men compared to women for a privately insured U.S.

POPULATION

Future studies aimed at identifying and understanding the barriers to diagnosis of BDs in men are warranted.

Women and ethnoracial minorities with poor cardiovascular health measures associated with a higher risk of developing mood disorder

Background

Mood disorders (MDS) are a type of mental health illness that effects millions of people in the United States. Early prediction of MDS can give providers greater opportunity to treat these disorders. We hypothesized that longitudinal cardiovascular health (CVH) measurements would be informative for MDS prediction.

Methods

To test this hypothesis, the American Heart Association’s Guideline Advantage (TGA) dataset was used, which contained longitudinal EHR from 70 outpatient clinics. The statistical analysis and machine learning models were employed to identify the associations of the MDS and the longitudinal CVH metrics and other confounding factors.

Results

Patients diagnosed with MDS consistently had a higher proportion of poor CVH compared to patients without MDS, with the largest difference between groups for Body mass index (BMI) and Smoking. Race and gender were associated with status of CVH metrics. Approximate 46% female patients with MDS had a poor hemoglobin A1C compared to 44% of those without MDS; 62% of those with MDS had poor BMI compared to 47% of those without MDS; 59% of those with MDS had poor blood pressure (BP) compared to 43% of those without MDS; and 43% of those with MDS were current smokers compared to 17% of those without MDS.

Conclusions

Women and ethnoracial minorities with poor cardiovascular health measures were associated with a higher risk of development of MDS, which indicated the high utility for using routine medical records data collected in care to improve detection and treatment for MDS among patients with poor CVH.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12911-021-01674-9.

Bipolar episodes after reproductive events in women with bipolar I disorder, A study of 919 pregnancies

BACKGROUND

Women with bipolar I disorder are at high risk for severe episodes after childbirth, but there is no study that provides an overview on bipolar episode risk both during pregnancy and after childbirth, miscarriage and induced abortion. The aim of this study was to determine the episode risk during all pregnancy outcomes subdivided by first and subsequent pregnancies.

METHODS

Participants were 436 women with bipolar I disorder from the Dutch Bipolar Cohort, having 919 pregnancies of which 762 resulted in a live childbirth, 118 ended in a miscarriage and 39 ended in induced abortion. Women reported on the occurrence of manic or depressed episodes during the perinatal period. Information about medication use was obtained by questionnaires.

RESULTS

Episode risk was 5.2% during pregnancy, and 30.1% in the postpartum period, with a peak in the early postpartum period. Risk of an episode was highest after live birth (34.4%), and lower after miscarriage (15.2%) and induced abortion (27.8%). Women with an episode during pregnancy or postpartum were less likely to have a second child compared to women with an uneventful first pregnancy (cOR=0.34; 95%CI: 0.22-0.51; p<0.001); if they had a second child their risk of an episode was significantly elevated with a subsequent pregnancy (cOR=6.17; 95%CI: 3.64-10.45; p<0.001).

LIMITATIONS

Retrospective cross-sectional design with assessment (partial) through self-report in a homogeneous population.

CONCLUSIONS

Women with bipolar I disorder have a six times higher risk of an episode after delivery compared to during pregnancy, therefore preventive strategies are particularly important immediately after delivery.

Kleine-Levin syndrome is associated with birth difficulties and genetic variants in the TRANK1 gene loci

Kleine-Levin syndrome (KLS) is a rare disorder characterized by severe episodic hypersomnia, with cognitive impairment accompanied by apathy or disinhibition. Pathophysiology is unknown, although imaging studies indicate decreased activity in hypothalamic/thalamic areas during episodes. Familial occurrence is increased, and risk is associated with reports of a difficult birth. We conducted a worldwide case-control genome-wide association study in 673 KLS cases collected over 14 y, and ethnically matched 15,341 control individuals. We found a strong genome-wide significant association (rs71947865, Odds Ratio [OR] = 1.48, P = 8.6 × 10^-9) within the 3'region of TRANK1 gene locus, previously associated with bipolar disorder and schizophrenia. Strikingly, KLS cases with rs71947865 variant had significantly increased reports of a difficult birth. As perinatal outcomes have dramatically improved over the last 40 y, we further stratified our sample by birth years and found that recent cases had a significantly reduced rs71947865 association. While the rs71947865 association did not replicate in the entire follow-up sample of 171 KLS cases, rs71947865 was significantly associated with KLS in the subset follow-up sample of 59 KLS cases who reported birth difficulties (OR = 1.54, P = 0.01). Genetic liability of KLS as explained by polygenic risk scores was increased (pseudo R ² = 0.15; P < 2.0 × 10^-22 at P = 0.5 threshold) in the follow-up sample. Pathway analysis of genetic associations identified enrichment of circadian regulation pathway genes in KLS cases. Our results suggest links between KLS, circadian regulation, and bipolar disorder, and indicate that the TRANK1 polymorphisms in conjunction with reported birth difficulties may predispose to KLS.

Residential green space structures are associated with a lower risk of bipolar disorder: A nationwide population-based study in Taiwan

Although many researchers have identified the potential psychological benefits offered by greenness, the association between green space structures and mental disorders is not well understood. The purpose of this study was to identify associations between green space structures and the incidence of bipolar disorder. To this end, we investigated 1,907,776 individuals collected from Taiwan's National Health Insurance Research Database. After a follow-up investigation from 2005 to 2016, among those with no history of bipolar disorder, 20,548 individuals were further found to be diagnosed with bipolar disorder. A geographic information system and landscape index were used to quantify three indices of green space structures: mean patch area (area and edge), mean fractal dimension index (shape), and mean proximity index (proximity). Additionally, greenness indices, the normalized difference vegetation index, and the enhanced vegetation index were used to confirm the association between greenness and incidence of bipolar disorder. These five indices were used to represent the individual's exposure according to the township of the hospital that they most frequently visited with symptoms of the common cold. Spearman's correlation analysis was performed to select variables by considering their collinearity. Subsequently, the frailty model for each index was used to examine the specific associations between those respective indices and the incidence of bipolar disorder by adjusting for related risk factors, such as socioeconomic status, metabolic syndrome, and air pollution. A negative association was identified between the mean patch area and the mean proximity index, and the incidence of bipolar disorder. In contrast, a positive association was found between the mean fractal dimension index and the incidence of bipolar disorder. We observed similar results in sensitivity testing and subgroup analysis. Exposure to green spaces with a larger area, greater proximity, lower complexity, and greener area may reduce the risk of bipolar disorder.

Month of birth and mental disorders: A population-based study and validation using global meta-analysis

OBJECTIVE

Month of birth (MOB) is associated with specified mental disorders (MDs). However, whether these relationships extend to all MDs remains unclear. We investigate the association using a population-based cohort study and a meta-analysis.

METHODS

First, we examined patients with 34 DSM-5-classified MDs in the Taiwan national database. We estimated the relative risk ratios (RR) of each illness in each MOB relative to that in the general population and assessed the periodicity, with six further sensitivity analyses. Second, we searched PubMed, Embase, and Cochrane for related articles through 31 December 2020. We used a random-effects model, pooled RRs with 95% confidence intervals of each MOB from the identified studies, and transformed them from MOB to relative age in a year or season.

RESULTS

The cohort included 1,951,777 patients. Except for posttraumatic stress disorder, dissociative disorders, feeding/eating disorders, gender dysphoria, and paraphilic disorders, the other MDs had significant MOB periodicity. The meta-analysis included 51 studies investigating 10 MDs. The youngest age at the start of school owing to MOB was associated with the highest RRs of intellectual disability (1.13), autism (1.05), attention-deficit/hyperactivity disorder (1.13). Winter births had significant risks of schizophrenia (1.04), bipolar I disorder (1.02), and major depressive disorder (1.01), and autumn births had a significant risk of alcohol use disorder (1.02). No significant associations between season of birth and Alzheimer's disease, or eating disorders were found.

CONCLUSIONS

MOB is related to the risks of certain MDs. This finding provides a reference for future research on the etiology of MDs.

The Rap1 small GTPase is a critical mediator of the effects of stress on prefrontal cortical dysfunction

The neural molecular and biochemical response to stress is a distinct physiological process, and multiple lines of evidence indicate that the prefrontal cortex (PFC) is particularly sensitive to, and afflicted by, exposure to stress. Largely through this PFC dysfunction, stress has a characterized role in facilitating cognitive impairment, which is often dissociable from its effects on non-cognitive behaviors. The Rap1 small GTPase pathway has emerged as a commonly disrupted intracellular target in neuropsychiatric conditions, whether it be via alterations in Rap1 expression or through alterations in the expression of direct and specific upstream Rap1 activators and inhibitors. Here we demonstrate that escalating, intermittent stress increases Rap1 in mouse PFC synapses, results in cognitive impairments, and reduces the preponderance of mature dendritic spines in PFC neurons. Using viral-mediated gene transfer, we reveal that the hyper-induction of Rap1 in the PFC is sufficient to drive stress-relevant cognitive and synaptic phenotypes. These findings point to Rap1 as a critical mediator of stress-driven neuronal and behavioral pathology and highlight a previously unrecognized involvement for Rap1 in novelty-driven PFC engagement.

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.

Bipolar disorder: Trimodal age-at-onset distribution

OBJECTIVE

Bipolar disorder (BD) is a chronic mental health disorder with significant morbidity and mortality. Age at onset (AAO) may be a key variable in delineating more homogeneous subgroups of BD patients. However, no known research has systematically assessed how BD age-at-onset subgroups should be defined.

METHODS

We systematically searched the following databases: Cochrane Central Register of Controlled Trials, PsycINFO, MEDLINE, Embase, CINAHL, Scopus, Proquest Dissertations and Theses, Google Scholar and BIOSIS Previews. Original quantitative English language studies investigating AAO in BD were sought.

RESULTS

A total of 9454 unique publications were identified. Twenty-one of these were included in data analysis (n = 22981 BD participants). Fourteen of these studies (67%, n = 13626 participants) found a trimodal AAO distribution: early-onset (µ = 17.3, σ = 1.19, 45% of sample), mid-onset (µ = 26.0, σ = 1.72, 35%), and late-onset (µ = 41.9, σ = 6.16, 20%). Five studies (24%, n = 1422 participants) described a bimodal AAO distribution: early-onset (µ = 24.3, σ = 6.57, 66% of sample) and late-onset (µ = 46.3, σ = 14.15, 34%). Two studies investigated cohort effects on BD AAO and found that when the sample was not split by cohort, a trimodal AAO was the winning model, but when separated by cohort a bimodal distribution fit the data better.

CONCLUSIONS

We propose that the field conceptualises bipolar disorder age-at-onset subgroups as referring broadly to life stages. Demarcating BD AAO groups can inform treatment and provide a framework for future research to continue to investigate potential mechanisms of disease onset.

Association of insomnia with mania in Lebanese patients with bipolar disorder

OBJECTIVE

To assess: (1) the association between insomnia experienced at admission, sociodemographic and other patients' characteristics and mania; and (2) the variation of insomnia and mania before and after treatment in bipolar patients with manic episodes (type I).

METHODS

Sixty-two patients were interviewed shortly after their admission to the hospital (after 3 to 5 days). The current symptoms experienced by the patients were assessed upon admission and again at discharge from the hospital.

RESULTS

A poorer quality of sleep (higher PSQI scores) (Beta=0.590) was significantly associated with higher mania, whereas the intake of SSRIs (Beta=-5.952) and TCAs (Beta=-8.181) was significantly associated with lower mania. Furthermore, highly significant reductions were reported in the PSQI scores (4.96 vs. 2.75, P<0.001), ISI scores (8.30 vs. 3.45, P<0.001) and YMRS scores (8.60 vs. 3.06, P<0.001) between admission to and discharge from the hospital.

CONCLUSION

Insomnia in patients with bipolar disorder type I is associated with mania, with a significant reduction of sleep problems seen during a period of approximately 20 days of hospitalization. Further longitudinal studies are needed to confirm the validity of our results and identify the causes. In the meantime, this research recommends a strategy to improve sleeplessness experienced during inter-episode phases may be helpful in preventing manic episodes in BD.

Environmental Risk Factors for Bipolar Disorders and High-Risk States in Adolescence: A Systematic Review

Background and objectives: A deeper comprehension of the role that environmental risk factors play in the development of adolescent Bipolar Disorder (BD), as well as in the evolution of high-risk states for BD, may entangle further prevention and treatment advances. The present systematic review is aimed at critically summarizing evidence about the role that environmental risk factors play in the development of BD in adolescence and their interaction with BD high-risk states. Materials and Methods: MEDLINE/Pubmed, Scopus and Web of Science datasets were systematically searched until 4 September 2020. Original studies that reported information about the role of environmental risk factors in the development of BD during adolescence, or assessing their influence on the development of psychopathology in high-risk states for BD, were considered for inclusion. Two blind researchers performed title/abstract, full-text screening, and hand-screening of relevant references. The risk of bias was assessed by means of the Newcastle-Ottawa Scale. Results: Fourteen studies were included in the review. Negative stressful life events, particularly sexual and physical abuse, but also emotional mistreatment, were associated with more severe psychopathology in adolescents with BD, as well as with higher risk for developing mood disorders in BD offspring. Similar findings were detected for familial environment-related features, such as parental rejection and low perceived care, while no univocal results were found when analyzing familial functioning. Conclusions: The present systematic review confirmed the relevant role that environmental risk factors, particularly negative stressful live events and family-related features, play in the development of BD psychopathology during adolescence. Future studies are expected to clarify possible further environmental factors that may be implicated in the development of BD during youth that may serve as target of prevention and early treatment strategies.

Maternal Type-I interferon signaling adversely affects the microglia and the behavior of the offspring accompanied by increased sensitivity to stress

Viral infection during pregnancy is often associated with neuropsychiatric conditions. In mice, exposure of pregnant dams to the viral mimetic poly(I:C), serves as a model that simulates such pathology in the offspring, through a process known as Maternal Immune Activation (MIA). To investigate the mechanism of such effect, we hypothesized that maternal upregulation of Type-I interferon (IFN-I), as part of the dam's antiviral response, might contribute to the damage imposed on the offspring. Using mRNA sequencing and flow cytometry analyses we found that poly(I:C) treatment during pregnancy caused reduced expression of genes related to proliferation and cell cycle in the offspring's microglia relative to controls. This was found to be associated with an IFN-I signature in the embryonic yolk sac, the origin of microglia in development. Neutralizing IFN-I signaling in dams attenuated the effect of MIA on the newborn's microglia, while systemic maternal administration of IFNβ was sufficient to mimic the effect of poly(I:C), and led to increased vulnerability of offspring's microglia to subsequent stress. Furthermore, maternal elevation of IFNβ resulted in behavioral manifestations reminiscent of neuropsychiatric disorders. In addition, by adopting a "two-hit" experimental paradigm, we show a higher sensitivity of the offspring to postnatal stress subsequent to the maternal IFNβ elevation, demonstrated by behavioral irregularities. Our results suggest that maternal upregulation of IFN-I, in response to MIA, interferes with the offspring's programmed microglial developmental cascade, increases their susceptibility to postnatal stress, and leads to behavioral abnormalities.

Bipolar disorder among married women in Bangladesh: Survey in Rajshahi city

BACKGROUND

Bipolar disorder (BPD) is a major mental disorder which not only affects the personal and social functioning of an individual, but also inflicts a huge economic burden on the family. Yet, the study of BPD in Bangladesh is rare and poorly documented. Responding to the dire need, we conducted a new study to determine the prevalence of, and detect the associated factors of, BPD among married women in Rajshahi City, Bangladesh.

METHODS

We conducted a cross-sectional study, selecting households in Rajshahi City using a multi-stage random sampling design. The data consisted of 279 married women, who were screened for BPD using the bipolar spectrum diagnostic scale (BSDS). Frequency distribution, chi-square test and binary logistic regression model were used respectively to determine the prevalence, identify the associated factors and quantify their effects on BPD.

RESULTS

The prevalence of BPD among married women in Rajshahi City was 2.5%, with an additional 7.2% classified as probable BPD. A binary logistic regression analysis established the following six main factors of BPD: (1) comorbid mental disorder [AOR = 8.232, 95% CI = (1.397, 50.000), p<0.05]; (2) poor relationship with husband [AOR = 11.775, 95% CI = (2.070, 66.667), p<0.01]; (3) poverty [AOR = 1.600, 95% CI = (2.086, 122.709), p<0.01]; (4) high educational level [AOR = 0.177, 95% CI = (0.037, 0.843), p<0.05]; (5) lack of immediate treatment if sick [AOR = 2.941, 95% CI = (1.259, 6.871), p<0.05]; and (6) death of beloved one/s [AOR = 2.768, 95% CI = (1.130, 6.777), p<0.05].

LIMITATIONS

Our survey involved self-reporting, which is typically affected by differing levels of understanding and bias. Also, a cross-sectional, observational study cannot establish an actual cause-and-effect relationship. Some other potentially important factors such as environment, lifestyle, familial customs, effects of drugs, treatment options and outcomes, etc. were not studied. Also, save mental disorder, all other comorbidities remained undocumented.

CONCLUSION

This study laid down the foundation for conducting further research on identifying different factors affecting BPD, and for studying other issues related to BPD among married women in Bangladesh. Among such factors are familial environment and culture, comorbidities, treatment options, treatment outcomes, biochemical feature, environmental factors, etc. This study also recommends that, while treating BPD patients, health professionals should focus on comorbidities and family matters.

Mania-like elevated mood in rats: Enhanced 50-kHz ultrasonic vocalizations after sleep deprivation

Mania is characterized by elevated drive and mood but animal models of mania have often neglected elevated mood. Ultrasonic vocalizations (USV) of 50-kHz emitted by rats are thought to index the subject's positive affective state. Fifty-kHz USV emission is increased by amphetamine, an effect blocked by lithium administration. Sleep deprivation (SD) is an environmental model of mania and the present study evaluated SD effects on behavioral activity and USV emission, together with the impact of lithium treatment. Adult rats were submitted to 24h or 72h SD, and locomotor activity and USV emission were assessed. To test their sensitivity to a standard antimanic drug, these behavioral parameters were also evaluated after acute administration of lithium carbonate (25, 50 or 100 mg/kg, i.p.). Striatal monoamine content was measured post-mortem. SD (24h and 72h) led to increased locomotor activity, rearing behavior and 50-kHz USV emission, together with a change in the call profile characterized by an increase in the percentage of frequency-modulated 50-kHz USV, which may indicate the mania-like consequences of SD. Importantly, all SD effects were reverted by lithium administration. SD also led to a decrease in dopamine content in the ventral striatum, while increasing dopamine turnover. In conclusion, SD increased 50-kHz USV emission, an effect prevented by acute lithium administration. This suggests 50-kHz USV as a new marker for mania-like elevated mood, which shows construct validity (associated with increased dopaminergic tone), face validity (reflecting increased positive affect) and predictive validity (high sensitivity to lithium treatment).

An explorative study on coping flexibility with behavioral approach system-activating stimuli: A comparison of people with and without bipolar disorder

Life events play a significant role in affecting mood symptoms of people with bipolar disorder (BD). However, we lack empirical data about the associations among disorder, mood state, behavioral activation system (BAS) sensitivity, and psychosocial functioning level. Thus, the present study aimed to identify the role of coping flexibility with BAS activating stimuli in relation to mood states among a sample of individuals with BD (n = 90) and a healthy control group (n = 90). Through multiple regressions, the moderating role of coping flexibility was determined. Findings showed that coping flexibility had an additional value in predicting mood states beyond BAS sensitivity and psychosocial functioning level. Specifically, perceived controllability was considerably important for the BD group, whereas fit index was crucial in the controls. In addition, a moderation analysis showed that perceived controllability alleviated the effects of BD diagnosis, BAS sensitivity, and psychosocial functioning level on mood states. Theoretically, this study helps integrate the concept of coping flexibility into the BAS dysregulation theory as it applies to BD. The practical implication for enhancing mindfulness practice is also discussed.

Epidemiology and risk factors for bipolar disorder

Bipolar disorder is a multifactorial illness with uncertain aetiology. Knowledge of potential risk factors enables clinicians to identify patients who are more likely to develop bipolar disorder, which directs further investigation, follow up and caution when prescribing. Ideally, identifying directly causative factors for bipolar disorder would enable intervention on an individual or population level to prevent the development of the illness, and improve outcomes through earlier treatment. This article reviews the epidemiology of bipolar disorder, along with putative demographic, genetic and environmental risk factors, while assessing the strength of these associations and to what extent they might be said to be 'causative'. While numerous genetic and environmental risk factors have been identified, the attributable risk of individual factors is often small, and most are not specific to bipolar disorder but are associated with several mental illnesses. Therefore, while some genetic and environmental factors have strong evidence supporting their association with bipolar disorder, fewer have sufficient evidence to establish causality. There is increasing interest in the role of specific gene-environment interactions, as well as the mechanisms by which risk factors interact to lead to bipolar disorder.

Vitamin D, Folate and the Intracranial Volume in Schizophrenia and Bipolar Disorder and Healthy Controls

Vitamin D and folate deficiency are considered risk factors for schizophrenia and bipolar disorders, but it is unknown how vitamin D and folate influence the growing brain, cranium or the clinical phenotype. Serum vitamin D and folate levels are in part genetically regulated. We investigated whether adult vitamin D and folate levels are associated with the intracranial volume (ICV) under the hypothesis that developmental vitamin D or folate levels influence neurodevelopment and that current levels are associated with ICV. Ninety patients with severe mental disorders and 91 healthy controls underwent 3 T magnetic resonance imaging and serum sampling. Multiple linear regression was used to assess the contribution of serum vitamin D, folate and patient-control status on ICV. We show that vitamin D levels were within lower range for patients and controls (48.8 ± 22.1 nmol/l and 53.4 ± 20.0 nmol/l, respectively). A significant positive association was found between vitamin D and ICV (p = 0.003, r = 0.22), folate was trend-significantly associated with ICV. Folate and vitamin D were significantly associated (p = 0.0001, r = 0.28). There were nonsignificant patient-control differences and no interaction effects. The results suggest that Vitamin D is associated with ICV as detected in the adult. Further studies are warranted for replication and to investigate possible mechanisms and genetic associations.

Evidence-Based Assessment from Simple Clinical Judgments to Statistical Learning: Evaluating a Range of Options Using Pediatric Bipolar Disorder as a Diagnostic Challenge

Reliability of clinical diagnoses is often low. There are many algorithms that could improve diagnostic accuracy, and statistical learning is becoming popular. Using pediatric bipolar disorder as a clinically challenging example, we evaluated a series of increasingly complex models ranging from simple screening to a supervised LASSO regression in a large (N=550) academic clinic sample. We then externally validated models in a community clinic (N=511) with the same candidate predictors and semi-structured interview diagnoses, providing high methodological consistency; the clinics also had substantially different demography and referral patterns. Models performed well according to internal validation metrics. Complex models degraded rapidly when externally validated. Naïve Bayesian and logistic models concentrating on predictors identified in prior meta-analyses tied or bettered LASSO models when externally validated. Implementing these methods would improve clinical diagnostic performance. Statistical learning research should continue to invest in high quality indicators and diagnoses to supervise model training.

A Double-Blind and Placebo-Controlled Trial of Aripiprazole in Symptomatic Youths at Genetic High Risk for Bipolar Disorder

OBJECTIVE

To determine if acute treatment with aripiprazole (APZ) would be superior to treatment with placebo in reducing dysfunctional symptoms of elevated mood and/or irritability in symptomatic children and adolescents at familial high risk for bipolar disorder (BPD) whose mood episodes occur spontaneously. These are patients we have previously referred to as suffering from "cyclotaxia."

METHODS

This was single-site, randomized, double-blind, placebo-controlled outpatient clinical trial in which youths aged 5-17 years who met diagnostic criteria for either cyclothymic disorder (CYC) or BPD not otherwise specified (BP-NOS) were randomly assigned to receive either APZ or placebo. Eligible participants had at least one parent with BPD, another first- or second-degree relative afflicted with a mood disorder, and also had not responded to psychotherapy. Treatment with APZ was initiated at a dose of approximately 0.1 mg/kg/day and could be increased by approximately 0.05 mg/kg/day at each study visit. Patients were seen weekly for 4 weeks and then every other week thereafter for 12 weeks. The primary outcome measure was mean change from baseline on Young Mania Rating Scale (YMRS) total score.

RESULTS

A total of 59 patients (30 APZ, 29 placebo) aged 11.8 (SD = 2.7) years were randomized and returned for at least one postbaseline assessment. The mean total daily doses of active APZ and placebo were 7.1 mg (SD = 3.7) and 7.4 mg (SD = 4.2), respectively. At the 12-week time point, APZ was superior to placebo on the primary outcome measure (p < 0.005). Most adverse events were mild and transient in nature. There was a significant difference in weight gain from baseline between patients who received APZ (2.3 kg [SD = 3.3]) and those who received placebo (0.7 kg [SD = 1.8]).

CONCLUSION

This double-blind trial found that APZ was significantly more efficacious than placebo in reducing symptoms of mania in children and adolescents with cyclotaxia.

Lack of Social Support Raises Stress Vulnerability in Rats with a History of Ancestral Stress

Stress is a primary risk factor for psychiatric disorders. However, it is not fully understood why some stressed individuals are more vulnerable to psychiatric disorders than others. Here, we investigated whether multigenerational ancestral stress produces phenotypes that are sensitive to depression-like symptoms in rats. We also examined whether social isolation reveals potentially latent sensitivity to depression-like behaviours. F4 female rats born to a lineage of stressed mothers (F0-F3) received stress in adulthood while housed in pairs or alone. Social isolation during stress induced cognitive and psychomotor retardation only in rats exposed to ancestral stress. Social isolation also hampered the resilience of the hypothalamic-pituitary-adrenal axis to chronic stress and reduced hippocampal volume and brain-derived neurotrophic factor (BDNF) expression. Thus, synergy between social isolation and stress may unmask a latent history of ancestral stress, and raises vulnerability to mental health conditions. The findings support the notion that social support critically promotes stress coping and resilience.

Systematic assessment of environmental risk factors for bipolar disorder: an umbrella review of systematic reviews and meta-analyses

OBJECTIVES

The pathophysiology of bipolar disorder is likely to involve both genetic and environmental risk factors. In our study, we aimed to perform a systematic search of environmental risk factors for BD. In addition, we assessed possible hints of bias in this literature, and identified risk factors supported by high epidemiological credibility.

METHODS

We searched the Pubmed/MEDLINE, EMBASE and PsycInfo databases up to 7 October 2016 to identify systematic reviews and meta-analyses of observational studies that assessed associations between putative environmental risk factors and BD. For each meta-analysis, we estimated its summary effect size by means of both random- and fixed-effects models, 95% confidence intervals (CIs), the 95% prediction interval, and heterogeneity. Evidence of small-study effects and excess of significance bias was also assessed.

RESULTS

Sixteen publications met the inclusion criteria (seven meta-analyses and nine qualitative systematic reviews). Fifty-one unique environmental risk factors for BD were evaluated. Six meta-analyses investigated associations with a risk factor for BD. Only irritable bowel syndrome (IBS) emerged as a risk factor for BD supported by convincing evidence (k=6; odds ratio [OR]=2.48; 95% CI=2.35-2.61; P<.001), and childhood adversity was supported by highly suggestive evidence. Asthma and obesity were risk factors for BD supported by suggestive evidence, and seropositivity to Toxoplasma gondii and a history of head injury were supported by weak evidence.

CONCLUSIONS

Notwithstanding that several environmental risk factors for BD were identified, few meta-analyses of observational studies were available. Therefore, further well-designed and adequately powered studies are necessary to map the environmental risk factors for BD.

The COMT Val158Met Polymorphism Is Associated With Response to Add-on Dextromethorphan Treatment in Bipolar Disorder

PURPOSE/BACKGROUND

We previously conducted a randomized, double-blind, controlled, 12-week study evaluating the effect of add-on dextromethorphan (DM), a noncompetitive N-methyl-D-aspartate receptor antagonist, on patients with bipolar disorder (BD) treated using valproate (VPA), which showed negative clinical differences. The genetic variation between each individual may be responsible for interindividual differences. The catechol-O-methyltransferase (COMT) gene has been a candidate gene for BD. In the current study, we investigated whether the COMT Val158Met polymorphism predicts treatment response to VPA + add-on DM and to VPA + placebo.

METHODS/PROCEDURES

Patients with BD (n = 309) undergoing regular VPA treatments were randomly assigned to groups given either add-on DM (30 mg/d) (n = 102), DM (60 mg/d) (n = 101), or placebo (n = 106) for 12 weeks. The Hamilton Depression Rating Scale and Young Mania Rating Scale were used to evaluate clinical response during weeks 0, 1, 2, 4, 8, and 12. The genotypes of the COMT Val158Met polymorphism were determined using polymerase chain reaction plus restriction fragment length polymorphism analysis. To adjust for within-subject dependence over repeated assessments, multiple linear regression with generalized estimating equation methods was used.

FINDINGS/RESULTS

When stratified by the COMT Val158Met genotypes, significantly greater decreases in Hamilton Depression Rating Scale scores were found in the VPA + DM (30 mg/d) group in patients with the Val/Met genotype (P = 0.008).

CONCLUSIONS

We conclude that the COMT Val158Met polymorphism may influence responses to DM (30 mg/d) by decreasing depressive symptoms in BD patients.

Relationship between childhood adversity and bipolar affective disorder: systematic review and meta-analysis

BACKGROUND

The relationship between childhood adversity and bipolar affective disorder remains unclear.

AIMS

To understand the size and significance of this effect through a statistical synthesis of reported research.

METHOD

Search terms relating to childhood adversity and bipolar disorder were entered into Medline, EMBASE, PsycINFO and Web of Science. Eligible studies included a sample diagnosed with bipolar disorder, a comparison sample and a quantitative measure of childhood adversity.

RESULTS

In 19 eligible studies childhood adversity was 2.63 times (95% CI 2.00-3.47) more likely to have occurred in bipolar disorder compared with non-clinical controls. The effect of emotional abuse was particularly robust (OR = 4.04, 95% CI 3.12-5.22), but rates of adversity were similar to those in psychiatric controls.

CONCLUSIONS

Childhood adversity is associated with bipolar disorder, which has implications for the treatment of this clinical group. Further prospective research could clarify temporal causality and explanatory mechanisms.

Modeling neurodevelopmental cognitive deficits in tasks with cross-species translational validity

Numerous psychiatric disorders whose cognitive dysfunction links to functional outcome have neurodevelopmental origins including schizophrenia, autism and bipolar disorder. Treatments are needed for these cognitive deficits, which require development using animal models. Models of neurodevelopmental disorders are as varied and diverse as the disorders themselves, recreating some but not all aspects of the disorder. This variety may in part underlie why purported procognitive treatments translated from these models have failed to restore functioning in the targeted patient populations. Further complications arise from environmental factors used in these models that can contribute to numerous disorders, perhaps only impacting specific domains, while diagnostic boundaries define individual disorders, limiting translational efficacy. The Research Domain Criteria project seeks to 'develop new ways to classify mental disorders based on behavioral dimensions and neurobiological measures' in hopes of facilitating translational research by remaining agnostic toward diagnostic borders derived from clinical presentation in humans. Models could therefore recreate biosignatures of cognitive dysfunction irrespective of disease state. This review highlights work within the field of neurodevelopmental models of psychiatric disorders tested in cross-species translational cognitive paradigms that directly inform this newly developing research strategy. By expounding on this approach, the hopes are that a fuller understanding of each model may be attainable in terms of the cognitive profile elicited by each manipulation. Hence, conclusions may begin to be drawn on the nature of cognitive neuropathology on neurodevelopmental and other disorders, increasing the chances of procognitive treatment development for individuals affected in specific cognitive domains.

Gestational influenza and risk of hypomania in young adulthood: prospective birth cohort study

BACKGROUND

Previous studies have suggested a possible link between exposure to influenza in utero and bipolar disorder in adulthood. Using data from a prospective birth cohort, we aimed to test for an association between exposure to gestational influenza and the experience of hypomania assessed in early adulthood.

METHODS

We used data on 2957 participants from the Avon Longitudinal Study of Parents and Children (ALSPAC). The two main outcomes of interest were hypomania, assessed using the Hypomania Checklist (HCL-32) at age 22-23, and 'hypomania plus previous psychotic experiences (PE)'. Maternally-reported gestational influenza was the exposure of interest. Multivariable logistic regression was used and estimates of association were adjusted for a range of possible confounding factors, including maternal smoking in pregnancy.

RESULTS

Relative to controls, rates of exposure to gestational influenza were higher for participants with hypomania (24.0%) and for participants with 'hypomania plus PE' (34.2%), but univariate and multivariable analyses of an association between gestational influenza and hypomania (with and without previous PE) were not significant.

LIMITATIONS

The response rate to those who were sent the HCL-32 questionnaire was 36.8%. As a result, some analyses may have been under-powered to detect a true effect. Influenza infection during pregnancy was self-reported by mothers.

CONCLUSIONS

In this prospective population study, gestational influenza was not identified as a clear risk factor for lifetime hypomania or for 'hypomania with PEs' in young adult offspring. It is possible that previous reports of an association between gestational influenza and bipolar disorder in adulthood have been confounded by factors such as maternal smoking during pregnancy.

Individual and combined effects of maternal anemia and prenatal infection on risk for schizophrenia in offspring

BACKGROUND

Maternal iron deficiency and infection during pregnancy have individually been associated with increased risk of schizophrenia in the offspring, but possible interactions between the two remain unidentified thus far. Therefore, we determined the individual and combined effects of maternal infection during pregnancy and prepartum anemia on schizophrenia risk in the offspring.

METHODS

We conducted a population-based study with individual record linkage of the Danish Civil Registration System, the Danish Hospital Register, and the Central Danish Psychiatric Register. In a cohort of Danish singleton births 1,403,183 born between 1977 and 2002, 6729 developed schizophrenia between 1987 and 2012. Cohort members were considered as having a maternal history of anemia if the mother had received a diagnosis of anemia at any time during the pregnancy. Maternal infection was defined based on infections requiring hospital admission during pregnancy.

RESULTS

Maternal anemia and infection were both associated with increased risk of schizophrenia in unadjusted analyses (1.45-fold increase for anemia, 95% CI: 1.14-1.82; 1.32-fold increase for infection, 95% CI: 1.17-1.48). The effect of maternal infection remained significant (1.16-fold increase, 95% CI: 1.03-1.31) after adjustment for possible confounding factors. Combined exposure to anemia and an infection increased the effect size to a 2.49-fold increased schizophrenia risk (95% CI: 1.29-4.27). The interaction analysis, however, failed to provide evidence for multiplicative interactions between the two factors.

CONCLUSION

Our findings indicate that maternal anemia and infection have additive but not interactive effects, and therefore, they may represent two independent risk factors of schizophrenia.

Epidemiology and burden of bipolar disorder in Africa: a systematic review of data from Africa

BACKGROUND

Bipolar disorder impacts negatively on the patient, the family, as well as the society. It taxes the health care services due to a combination of the illness with associated medical and psychiatric comorbidities. In Africa, unfortunately, knowledge of the epidemiology and burden of bipolar disorder is based mainly on studies from the USA and Europe. In this systematic review of literature from Africa, we highlight the epidemiology and burden of bipolar disorder.

METHODS

A systematic review of publications from Africa relating to the epidemiology and burden of bipolar disorder was conducted.

RESULT

Data from community surveys conducted in Nigeria and Ethiopia indicated a lifetime prevalence estimate of 0.1 % to 1.83 for bipolar disorder. Missed diagnosis rate of bipolar disorder was up to 36.2 %. In one study, 8.1 % of the males and 5.4 % of the females reported a previous suicide attempt. A study showed that up to 60 % of patients with bipolar disorder had at least one comorbidity. There were no reports on all-cause mortality and cost of illness.

CONCLUSION

Bipolar disorder is a major mental health problem in Africa. Scientific findings on bipolar disorder from Africa are consistent with the existing literature from other parts of the world. There still exists a dearth of high quality studies addressing the epidemiological, clinical, social, and economic burden of the disorder.

Childhood abuse, family history and stressors in older patients with bipolar disorder in relation to age at onset

OBJECTIVES

The aim of this study is to explore the family history of psychiatric disorders, childhood abuse, and stressors in older patients with Bipolar Disorder (BD) and the association of these variables with the age at onset of BD.

METHODS

The Questionnaire for Bipolar Disorder (QBP) and the Mini International Neuropsychiatric Interview (MINI-Plus) were obtained from 78 patients aged 60 and over to determine diagnosis, age at onset of the first affective episode, childhood abuse, family history of psychiatric disorders and past and recent stressful life events.

RESULTS

Increased family history of psychiatric disorders was the only factor associated with an earlier age at onset of BD. Less family history of psychiatric disorders and more negative stressors were significantly associated with a later age at onset of the first (hypo)manic episode.

LIMITATIONS

Age at onset, history of childhood abuse, and past stressful life events were assessed retrospectively. Family members of BD patients were not interviewed.

CONCLUSIONS

Our findings suggest that age at onset can define distinct BD phenotypes. More specifically there was a stronger heredity of BD and other psychiatric disorders in patients with an early age of onset of BD. Negative stressors may play a specific role in patients with a late age at onset of a first (hypo)manic episode.

Interaction of DRD2TaqI, COMT, and ALDH2 genes associated with bipolar II disorder comorbid with anxiety disorders in Han Chinese in Taiwan

It is hypothesized that dopaminergic genes-dopamine type-2 receptor (DRD2), aldehyde dehydrogenase 2 (ALDH2), and catechol-O-methyltransferase (COMT)-are associated with bipolar disorder (BP) and anxiety disorder (AD). Bipolar II (BP-II) is reported to be highly comorbid with AD. We examined whether interactions among these three genes are susceptibility factors in BP-II with AD (BP-II(+AD)) and without AD (BP-II(-AD)). In this study, we hypothesize that the interaction of the dopaminergic genes between BP-II(+AD) and BP-II(-AD) is significant different. We recruited 1260 participants: 495 with BP-II(-AD), 170 with BP-II(+AD), and 595 healthy controls without BP-II or AD. Genotyping was done using polymerase chain reactions plus restriction fragment length polymorphism analysis. Genotypic frequencies of the DRD2TaqIA, COMT, and ALDH2 polymorphisms between the two BP-II groups were nonsignificant. In logistic regression, the ALDH2 and DRD2TaqIA genes showed a main effect that was protective against BP-II(-AD) (odds ratio [OR] = 0.497, p = 0.010, and OR = 0.415, p = 0.017, respectively). The interaction of DRD2TaqIA A1/A1 and ALDH2*1/*1 had a significant risk effect on the BP-II(-AD) group (OR = 7.177, p < 0.001). However, the interaction of DRD2TaqIA A1/A1, ALDH2*1/*1, and COMTMet/Met&Val/Met become a weak protective factor against BP-II(-AD) (OR = 0.205, p = 0.047). All of the significant results described above are found only in BP-II(-AD). This study supports the hypothesis the interaction of the dopaminergic genes between BP-II(+AD) and BP-II(-AD) is significant different,, and provides additional evidence that the DRD2TaqIA A1/A1, ALDH2*1/*1 and COMT genes interact in BP-II(-AD) but not in BP-II(+AD).

Relationship between sunlight and the age of onset of bipolar disorder: an international multisite study

BACKGROUND

The onset of bipolar disorder is influenced by the interaction of genetic and environmental factors. We previously found that a large increase in sunlight in springtime was associated with a lower age of onset. This study extends this analysis with more collection sites at diverse locations, and includes family history and polarity of first episode.

METHODS

Data from 4037 patients with bipolar I disorder were collected at 36 collection sites in 23 countries at latitudes spanning 3.2 north (N) to 63.4 N and 38.2 south (S) of the equator. The age of onset of the first episode, onset location, family history of mood disorders, and polarity of first episode were obtained retrospectively, from patient records and/or direct interview. Solar insolation data were obtained for the onset locations.

RESULTS

There was a large, significant inverse relationship between maximum monthly increase in solar insolation and age of onset, controlling for the country median age and the birth cohort. The effect was reduced by half if there was no family history. The maximum monthly increase in solar insolation occurred in springtime. The effect was one-third smaller for initial episodes of mania than depression. The largest maximum monthly increase in solar insolation occurred in northern latitudes such as Oslo, Norway, and warm and dry areas such as Los Angeles, California.

LIMITATIONS

Recall bias for onset and family history data.

CONCLUSIONS

A large springtime increase in sunlight may have an important influence on the onset of bipolar disorder, especially in those with a family history of mood disorders.

A potential interaction between COMT and MTHFR genetic variants in Han Chinese patients with bipolar II disorder

Bipolar II disorder (BP-II), characterized by recurrent dysregulation of mood, is a serious and chronic psychiatric illness. However, BP-II is commonly under-recognized, even in psychiatric settings. Because dopaminergic disturbance is thought to be involved in the development of bipolar disorder (BPD), it seems essential to investigate dopamine-related genes like the catechol-O-methyltransferase (COMT) gene, which are involved in dopamine metabolism, and the methylenetetrahydrofolate reductase (MTHFR) gene, which may affect COMT methylation and COMT function. The current study examined the association and interaction of the COMT Val158Met and MTHFR C677T variants with BP-II. Nine hundred seventy-eight participants were recruited: 531 with BP-II and 447 healthy controls. The genotypes of the COMT and MTHFR polymorphisms were determined using a polymerase chain reaction-restriction fragment length polymorphism analysis. Logistic regression analysis showed a significant interaction effect of the COMT Val158Met Val/Val genotype and the MTHFR C677T C/T + T/T genotype (P = 0.039) for the protective effect on the odds of developing BP-II. Our findings support preliminary evidence that the COMT and MTHFR genes interact in BP-II, and they imply the connection of both dopaminergic pathways and methylation pathways in the pathogenesis of BP-II.

Perinatal oxytocin increases the risk of offspring bipolar disorder and childhood cognitive impairment

BACKGROUND

We tested the hypothesis that perinatal oxytocin, given to pregnant women to induce labor, is related to offspring bipolar disorder (BP) and worse childhood cognitive performance among offspring. We also tested the association between childhood cognition and later BP.

METHODS

A population-based birth cohort derived from the Child Health and Development Study (CHDS) which included nearly all pregnant women receiving obstetric care from the Kaiser Permanente Medical Care Plan, Northern California Region (KPNC) between 1959 and 1966. Prospectively obtained medical and offspring cognitive performance were used. Potential cases with BP from the cohort were identified by database linkages. This protocol identified 94 cases who were matched 1:8 to controls.

RESULTS

Perinatal oxytocin was associated with a 2.4 times increased odds of later BP. Oxytocin was also associated with decreased performance on the Raven Matrices, but not on the Peabody Picture Vocabulary Test (PPVT). Childhood cognition was not associated with later BP.

LIMITATIONS

Loss to follow-up must be considered in all birth cohort studies. In addition, the childhood cognitive battery did not include tests related to multiple domains of cognition which have been associated with later BP. A third limitation is the modest sample size of those exposed to oxytocin.

CONCLUSIONS

This study provides evidence for a potentially important perinatal risk factor for BP and cognitive impairment in childhood. While the association between perinatal oxytocin and offspring BP must be viewed cautiously until further studies can attempt to replicate the result, it lends support to the broader view that neurodevelopmental factors contribute to BP.