Examining the relationship between genetic risk for depression and youth episodic stress exposure

BACKGROUND

Offspring of depressed mothers have elevated risk of developing depression because they are exposed to greater stress. While generally assumed that youth's increased exposure to stress is due to the environmental effects of living with a depressed parent, youth's genes may influence stress exposure through gene-environment correlations (rGEs). To understand the relationship between risk for depression and stress, we examined the effects of polygenic risk for depression on youth stress exposure.

METHODS

We examined the relations of a polygenic risk score (PRS) for depression (DEP-PRS), as well as PRSs for 5 other disorders, with youth stress exposure. Data were from a longitudinal study of a community sample of youth and their parents (n = 377) focusing on data collected at youth's aged 12 and 15 assessments.

RESULTS

Elevated youth DEP-PRS was robustly associated with increased dependent stress, particularly interpersonal events. Exploratory analyses indicated that findings were driven by major stress and were not moderated by maternal nor paternal history of depression, and of the 5 additional PRSs tested, only elevated genetic liability for bipolar I was associated with increased dependent stress-particularly non-interpersonal events.

LIMITATIONS

Like other PRS studies, we focused on those of European ancestry thus, generalizability of findings is limited.

CONCLUSION

Polygenic risk contributes to youth experiencing stressful life events which are dependent on their behavior. This rGE appears to be specific to genetic risk for mood disorders.

Traumatic events in childhood and adulthood in a diverse-ancestry sample and their role in bipolar disorder

We examined the presence of adverse events in both childhood and adulthood and the prevalence of PTSD in individuals with Bipolar Disorder (BD). There were 191 adults diagnosed with BD Type I and 924 controls, of predominantly African Ancestry (AA). All were administered the GPC-Screening Tool and the BD group the DIPAD. In addition Childhood adversities were measured using the ACE (from 0 to 10), about traumatic events before age 18 and lifetime adversities were measured with 15 questions adapted from the Study of Addiction: Genetics and Environment (A-SAGE (from 0 to 15) for all cases and controls. Probable PTSD (pPTSD) was measured with 4 questions on the GPC screener. Sum scores were calculated for the ACE and A-SAGE by tallying positive responses. Odd Ratios (OR) were used to measure the association between BD and Controls exposure to adversity. BD was associated with a significantly higher mean ACE score and A-SAGE score compared to controls. There was a significantly higher prevalence of pPTSD in the BD (54.5%) versus Controls (6.6%) as well. Greater OR's were seen in the BD compared to Controls for each ACE question (p<0.05). Results were similar for A-SAGE. Limitations include possible recall bias, and missing data.

Reward and Immune Systems in Emotion (RISE) prospective longitudinal study: Protocol overview of an integrative reward-inflammation model of first onset of major depression in adolescence

Background

Depression is associated with a reduced sensitivity to rewards and low reward-related brain function in cortico-striatal circuitry. A separate literature documents elevated peripheral inflammation in depression. Recently, integrated reward-inflammation models of depression have been proposed. These models draw on work indicating that peripheral inflammatory proteins access the brain, where they lower reward responsiveness. This blunted reward responsiveness is proposed to initiate unhealthy behaviors (substance use, poor diet), as well as sleep disruption and stress generation, which further heighten inflammation. Over time, dysregulation in reward responsiveness and immune signaling may synergize in a positive feedback loop, whereby dysregulation in each system exacerbates dysregulation in the other. Project RISE (Reward and Immune Systems in Emotion) provides a first systematic test of reward-immune dysregulation as a synergistic and dynamic vulnerability for first onset of major depressive disorder and increases in depressive symptoms during adolescence.

Methods

This NIMH-funded R01 study is a 3-year prospective, longitudinal investigation of approximately 300 community adolescents from the broader Philadelphia area, United States of America. Eligible participants must be 13-16 years old, fluent in English, and without a prior major depressive disorder. They are being selected along the entire dimension of self-reported reward responsiveness, with oversampling at the low tail of the dimension in order to increase the likelihood of major depression onsets. At Time 1 (T1), T3, and T5, each a year apart, participants complete blood draws to quantify biomarkers of low-grade inflammation, self-report and behavioral measures of reward responsiveness, and fMRI scans of reward neural activity and functional connectivity. At T1-T5 (with T2 and T4 six months between the yearly sessions), participants also complete diagnostic interviews and measures of depressive symptoms, reward-relevant life events, and behaviors that increase inflammation. Adversity history is assessed at T1 only.

Discussion

This study is an innovative integration of research on multi-organ systems involved in reward and inflammatory signaling in understanding first onset of major depression in adolescence. It has the potential to facilitate novel neuroimmune and behavioral interventions to treat, and ideally prevent, depression.

Inflammation, anxiety, and stress in bipolar disorder and borderline personality disorder: A narrative review

Bipolar disorder (BD) and borderline personality disorder (BPD) are serious and prevalent psychiatric diseases that share common phenomenological characteristics: symptoms (such as anxiety, affective lability or emotion dysregulation), neuroimaging features, risk factors and comorbidities. While several studies have focused on the link between stress and peripheral inflammation in other affective disorders such as anxiety or depression, fewer have explored this relationship in BD and BPD. This review reports on evidence showing an interplay between immune dysregulation, anxiety and stress, and how an altered acute neuroendocrine stress response may exist in these disorders. Moreover, we highlight limitations and confounding factors of these existing studies and discuss multidirectional hypotheses that either suggest inflammation or stress and anxiety as the primum movens in BD and BPD pathophysiology, or inflammation as a consequence of the pathophysiology of these diseases. Untangling these associations and implementing a transdiagnostic approach will have diagnostic, therapeutic and prognostic implications for BD and BPD patients.

The association between stressful life events and perceived quality of life among women attending infertility treatments: the moderating role of coping strategies and perceived couple's dyadic adjustment

BACKGROUND

Research highlighted that Stressful Life Events have high incidence among infertile patients and significant impact on physical and medical parameters related to reproductive functions, but their potential role among factors influencing the infertile patients' perception of fertility-related Quality of Life (QoL) has not been explored. The present study aims to investigate the associations of Stressful Life Events (Stressful events in the family of origin, In family pre-existing pregnancy difficulties, Health problems in childhood) with perceived fertility-related QoL in women attending infertility treatments, examining the potential moderating role of adopted coping strategies and perceived couple's dyadic adjustment.

METHODS

A questionnaire consisting of Socio-demographics and Infertility-related characteristics, Stress-inducing events in the couples' lives Questionnaire (FLS), Coping Orientations to Problem Experienced (COPE), Dyadic Adjustment Scale (DAS), and Core and Treatment subscales of Fertility Quality of Life (FertiQoL) was administered to 266 women attending infertility treatments. A descriptive correlational design with cross-sectional comparison was used. Results Logistic Regression Analyses after adjusting for socio-demographic and infertility-related characteristics revealed that women who reported Stressful events in the family of origin and In family pre-existing pregnancy difficulties were more likely to report lower levels of perceived Core QoL, while women who reported Health problems in childhood were more likely to report lower levels of perceived Treatment QoL. Couple's dyadic adjustment and specific coping strategies were significantly associated with perceived Core and Treatment QoL and they also significantly moderated the associations between stressful life events and perceived QoL.

CONCLUSIONS

Data provided original evidence on the strong association between stressful life events and perceived fertility-related QoL also highlighting individual and couples' resources to define counselling interventions with women attending infertility treatments.

Childhood factors associated with increased risk for mood episode recurrences in bipolar disorder-A systematic review

BACKGROUND

Bipolar Disorder (BD) is a recurrent illness associated with high morbidity and mortality. The frequency of mood episode recurrence in BD is highly heterogeneous and significantly impacts the person's psychosocial functioning and well-being. Understanding the factors associated with mood recurrences could inform the prognosis and treatment. The objective of this review is to summarize the literature on factors, present during childhood, that influence recurrence.

METHODOLOGY

A systematic review of PubMed (1946-2017) and PsycINFO (1884-2017) databases was conducted to identify candidate studies. Search terms included bipolar disorder, episodes, predictors, recurrences, and course. Study characteristics, risk for bias, and factors associated with recurrence were coded by two raters according to predetermined criteria.

RESULTS

Twenty child studies and 28 adult studies that retrospectively evaluated childhood variables associated with mood recurrences were included. Early age of onset, low socioeconomic status, comorbid disorders, inter-episode subsyndromal mood symptoms, BD-I/II subtypes, presence of stressors, and family history of BD were associated with higher number of recurrences.

LIMITATIONS

Risk factors and mood recurrences were assessed and defined in different ways, limiting generalizability.

CONCLUSION

Multiple factors are associated with increased risk of mood episode recurrence in BD. Interventions targeting modifiable factors could reduce the impact of BD. For example, treatment of comorbid disorders and subsyndromal mood symptoms, coupled with appropriate cognitive behavioral and family-focused therapies could ameliorate risk related to many clinical factors. When coupled with social services to address environmental factors, the number of episodes could be reduced and the course of BD significantly improved.

Suicidal behavior and stress generation in adolescents

Stress generation has potential to account for recurrent suicidal behavior. The current study represents a first step toward evaluating this possibility in a sample of adolescent psychiatric inpatients (n = 99; 79.80% female) followed over six months. At index admission, participants completed baseline measures of depressive symptom severity, suicidal ideation, lifetime history of suicide attempts, and negative life events using a contextual threat life stress interview. Negative life events since baseline were assessed at the follow-up assessment. Consistent with the stress generation hypothesis, lifetime number of suicide attempts prospectively predicted higher rates of dependent, but not independent, stress. Bayesian analyses also yielded substantial support for an association with overall dependent stress, but provided more modest support for specificity to this form of life stress relative to independent stress. Implications of these findings and directions for future research further clarifying the role of stress generation in suicidal behavior are discussed.

Childhood Trauma in Schizophrenia: Current Findings and Research Perspectives

Schizophrenia is a severe neuropsychiatric disorder with persistence of symptoms throughout adult life in most of the affected patients. This unfavorable course is associated with multiple episodes and residual symptoms, mainly negative symptoms and cognitive deficits. The neural diathesis-stress model proposes that psychosocial stress acts on a pre-existing vulnerability and thus triggers the symptoms of schizophrenia. Childhood trauma is a severe form of stress that renders individuals more vulnerable to developing schizophrenia; neurobiological effects of such trauma on the endocrine system and epigenetic mechanisms are discussed. Childhood trauma is associated with impaired working memory, executive function, verbal learning, and attention in schizophrenia patients, including those at ultra-high risk to develop psychosis. In these patients, higher levels of childhood trauma were correlated with higher levels of attenuated positive symptoms, general symptoms, and depressive symptoms; lower levels of global functioning; and poorer cognitive performance in visual episodic memory end executive functions. In this review, we discuss effects of specific gene variants that interact with childhood trauma in patients with schizophrenia and describe new findings on the brain structural and functional level. Additive effects between childhood trauma and brain-derived neurotrophic factor methionine carriers on volume loss of the hippocampal subregions cornu ammonis (CA)4/dentate gyrus and CA2/3 have been reported in schizophrenia patients. A functional magnetic resonance imaging study showed that childhood trauma exposure resulted in aberrant function of parietal areas involved in working memory and of visual cortical areas involved in attention. In a theory of mind task reflecting social cognition, childhood trauma was associated with activation of the posterior cingulate gyrus, precuneus, and dorsomedial prefrontal cortex in patients with schizophrenia. In addition, decreased connectivity was shown between the posterior cingulate/precuneus region and the amygdala in patients with high levels of physical neglect and sexual abuse during childhood, suggesting that disturbances in specific brain networks underlie cognitive abilities. Finally, we discuss some of the questionnaires that are commonly used to assess childhood trauma and outline possibilities to use recent biostatistical methods, such as machine learning, to analyze the resulting datasets.

Bipolar affective disorder and borderline personality disorder: Differentiation based on the history of early life stress and psychoneuroendocrine measures

INTRODUCTION

Borderline Personality Disorder (BPD) and Bipolar Affective Disorder (BD) have clinical characteristics in common which often make their differential diagnosis difficult. The history of early life stress (ELS) may be a differentiating factor between BPD and BD, as well as its association with clinical manifestations and specific neuroendocrine responses in each of these diagnoses.

OBJECTIVE

Assessing and comparing patients with BD and BPD for factors related to symptomatology, etiopathogenesis and neuroendocrine markers.

METHODOLOGY

The study sample consisted of 51 women, divided into 3 groups: patients with a clinical diagnosis of BPD (n = 20) and BD (n = 16) and healthy controls (HC, n = 15). Standardized instruments were used for the clinical evaluation, while the history of ELS was quantified with the Childhood Trauma Questionnaire (CTQ), and classified according to the subtypes: emotional abuse, physical abuse, sexual abuse, emotional neglect and physical neglect. The functioning of the hypothalamic-pituitary-adrenal (HPA) axis was evaluated by measuring a single plasma cortisol sample.

RESULTS

Patients with BPD presented with more severe psychiatric symptoms of: anxiety, impulsivity, depression, hopelessness and suicidal ideation than those with BD. The history of ELS was identified as significantly more prevalent and more severe in patients (BPD and BP) than in HC. Emotional abuse, emotional neglect and physical neglect also showed differences and were higher in BPD than BD patients. BPD patients had greater severity of ELS overall and in the subtypes of emotional abuse, emotional neglect and physical neglect than BD patients. The presence of ELS in patients with BPD and BP showed significant difference with lower cortisol levels when compared to HC. The endocrine evaluation showed no significant differences between the diagnoses of BPD and BD. Cortisol measured in patients with BPD was significantly lower compared to HC in the presence of emotional neglect and physical neglect. A significant negative correlation between the severity of hopelessness vs cortisol; and physical neglect vs cortisol were found in BPD with ELS. The single cortisol sample showed a significant and opposite correlations in the sexual abuse diagnosis-related groups, being a negative correlation in BD and positive in BPD.

DISCUSSION

Considering the need for a multi-factorial analysis, the differential diagnosis between BPD and BD can be facilitated by the study of psychiatric symptoms, which are more severe in the BPD patients with a history of early life stress. The function of the HPA axis assessed by this cortisol measure suggests differences between BPD and BP with ELS history.

CONCLUSION

The integrated analysis of psychopathology, ELS and neuroendocrine function may provide useful indicators to differentiate BPD and BD diagnoses. These preliminary data need to be replicated in a more significant sample with improved and multiple assessments of HPA axis activity.

Amygdala and hippocampus volumes are differently affected by childhood trauma in patients with bipolar disorders and healthy controls

OBJECTIVES

Volumetric studies on deep gray matter structures in bipolar disorder (BP) have reported contrasting results. Childhood trauma, a relevant environmental stressor for BP, could account for the variability of the results, modulating differences in the amygdala and hippocampus in patients with BP compared with healthy controls (HC). Our study aimed to test this hypothesis.

METHODS

We assessed 105 outpatients, diagnosed with bipolar disorder type I (BP-I) or bipolar disorder type II (BP-II) according to DSM-IV-TR criteria, and 113 HC subjects. History of childhood trauma was obtained using the Childhood Trauma Questionnaire (CTQ). High-resolution magnetic resonance imaging was performed on all subjects and volumes of the amygdala, hippocampus, nucleus accumbens, caudate, pallidum, putamen, and thalamus were measured using FreeSurfer.

RESULTS

Patients with BP showed a global reduction of deep gray matter volumes compared to HCs. However, childhood trauma modulated the impact of the diagnosis specifically on the amygdala and hippocampus. Childhood trauma was associated with bilateral decreased volumes in HCs and increased volumes in patients with BP.

CONCLUSIONS

The results suggest that childhood trauma may have a different effect in health and disease on volumes of gray matter in the amygdala and hippocampus, which are brain areas specifically involved in response to stress and emotion processing.

Kindling of Life Stress in Bipolar Disorder: Effects of Early Adversity

Most theoretical frameworks regarding the role of life stress in bipolar disorders (BD) do not incorporate the possibility of a changing relationship between psychosocial context and episode initiation across the course of the disorder. The kindling hypothesis theorizes that over the longitudinal course of recurrent affective disorders, the relationship between major life stressors and episode initiation declines (Post, 1992). The present study aimed to test an extension of the kindling hypothesis in BD by examining the effect of early life adversity on the relationship between proximal life events and prospectively assessed mood episodes. Data from 145 bipolar participants (59.3% female, 75.2% Caucasian, and mean age of 20.19 years; SD = 1.75 years) were collected as part of the Temple-Wisconsin Longitudinal Investigation of Bipolar Spectrum Project (112 Bipolar II; 33 Cyclothymic disorder). Participants completed a self-report measure of early adversity at baseline and interview-assessed mood episodes and life events at regular 4-month follow-ups. Results indicate that early childhood adversity sensitized bipolar participants to the effects of recent stressors only for depressive episodes and not hypomanic episodes within BD. This was particularly the case with minor negative events. The current study extends prior research examining the kindling model in BD using a methodologically rigorous assessment of life stressors and mood episode occurrence. Clinicians should assess experiences of early adversity in individuals with BD as it may impact reactivity to developing depressive episodes in response to future stressors.

Adverse Childhood Experiences Among Inpatient Youths with Severe and Early-Onset Psychiatric Disorders: Prevalence and Clinical Correlates

This study aimed to determine the prevalence and the clinical correlates of Adverse Childhood Experiences (ACEs) among 158 inpatient youths with two types of severe psychiatric disorders. ACEs were retrospectively collected with the ACEs scale and the List of Threatening Experiences Questionnaire in 77 patients hospitalized for a catatonic syndrome (average age 15.2 years) and 81 for a manic or mixed episode (average age 15.7 years). ACEs were frequent in youths suffering from bipolar disorder type I (BD-I) (58 %) and from catatonia (57 %), with around one quarter exposed to severe abuse (i.e., physical/sexual/emotional abuse or physical/emotional neglect). Youths with BD-I were more likely to be exposed to family violence compared to those with catatonia. Youths who had been exposed to ACEs did not exhibit a more severe presentation or a poorer response to treatment compared to others, either in the bipolar group or in the catatonic group.

Single Mother Parenting and Adolescent Psychopathology

Children raised in single-mother families are at increased risk for psychopathology, but the mechanisms that help explain this relationship are understudied. In a community sample of diverse adolescents (N = 385, 52 % female, 48 % Caucasian) and their mothers, we hypothesized that single mothers would be more likely than cohabitating mothers to engage in negative parenting behaviors, which would predict adolescent psychopathology prospectively. Single mothers were more likely to engage in psychologically controlling behaviors, which predicted to their adolescent offspring experiencing higher rates of depressive symptoms and externalizing disorders. Girls were more susceptible to depressive symptoms via psychologically controlling parenting than boys in single-mother families. Further, single mothers were more likely to engage in rejecting parenting behaviors, which predicted to a higher prevalence of adolescent externalizing disorders. Surprisingly, rejection in single-mother families predicted to less severe anxiety symptoms in adolescents relative to two-parent families. It is likely that single mothers are not inherently inferior parents relative to cohabitating mothers; rather, their parenting practices are often compromised by a myriad of demands and stressors. Consistent with this postulate, low socioeconomic status was associated with single motherhood and negative parenting behaviors. Clinical implications and study limitations are discussed.

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.

Cognitive Vulnerabilities to Depression for Adolescents in Single-Mother and Two-Parent Families

Although research consistently suggests that adolescents in single-mother families are at increased risk for depression, the mechanisms that explain this relationship are unclear. In a community sample of adolescents (N = 368; ages 12-16; 50 % female; 50 % White) and their mothers (42 % single), adolescents completed measures of depressive symptoms, rumination, and depressogenic inferential style at baseline and two yearly follow-ups. Mothers reported on stressful events that occurred in the child's life from birth until baseline. Adolescents raised by single mothers, relative to partnered mothers, experienced more childhood stressors and higher rumination levels at 1-year follow-up. Additionally, higher rumination mediated the relationship between single motherhood and greater youth depressive symptoms at the 2-year follow-up. Clinical implications and developmental considerations are discussed.

Moderate Childhood Stress Buffers Against Depressive Response to Proximal Stressors: A Multi-Wave Prospective Study of Early Adolescents

Although the majority of research in the field has focused on childhood stressors as a risk factor for psychopathology, a burgeoning body of literature has focused on the possible steeling effect of moderate types of stressful events. The current study investigated the effects of proximal life stressors on prospective changes in depressive symptoms, and whether a history of moderate childhood adversity would moderate this relationship in a multi-wave study of a diverse community sample of early adolescents (N = 163, 52 % female, 51 % Caucasian). Hierarchical linear modeling was run with four waves of data. Adolescents with greater moderately severe early life events evinced a blunted depressive symptom response to changes in proximal stressful events in the previous 9 months, compared to those with fewer early moderately severe experiences of adversity. These results held after controlling for between-subject factors such as race, gender, severe early life stress, and average stress over the four waves of data. Findings indicate that greater exposure to moderate childhood stressors may buffer against the negative effects of subsequent stressors, suggesting the importance of a nuanced developmental approach to studying the effects of early life stress.

Childhood maltreatment and unfavourable clinical outcomes in bipolar disorder: a systematic review and meta-analysis

BACKGROUND

Bipolar disorder affects up to one in 25 individuals and identification of early risk indicators of negative outcomes could facilitate early detection of patients with greatest clinical needs and risk. We aimed to investigate the association between childhood maltreatment and key negative outcomes in patients with bipolar disorder.

METHODS

For this systematic review and meta-analysis we searched MEDLINE, PsycINFO, and Embase to identify articles published before Jan 1, 2015, examining the association of maltreatment (physical, sexual, or emotional abuse, neglect, or family conflict) before age 18 years with clinical features and course of illness in bipolar disorder. Data were extracted from published reports and any missing information was requested from investigators. We did 12 independent random-effects meta-analyses to quantify the associations between childhood maltreatment and course of illness or clinical features.

FINDINGS

We initially identified 527 records and after unsuitable studies were removed, our search yielded 148 publications of which 30 were used in the meta-analysis. Patients with bipolar disorder and history of childhood maltreatment had greater mania severity (six studies, 780 participants; odds ratio [OR] 2·02, 95% CI 1·21-3·39, p=0·008), greater depression severity (eight studies, 1007 participants; 1·57, 1·25-1·99, p=0·0001), greater psychosis severity (seven studies, 1494 participants; 1·49, 1·10-2·04, p=0·011), higher risk of comorbidity with post-traumatic stress disorder (eight studies, 2494 participants; 3·60, 2·45-5·30, p<0·0001), anxiety disorders (seven studies, 5091 participants; 1·90, 1·39-2·61, p<0·0001), substance misuse disorders (11 studies, 5469 participants; 1·84, 1·41-2·39, p<0·0001), alcohol misuse disorder (eight studies, 5040 participants; 1·44, 1·13-1·83, p=0·003), earlier age of bipolar disorder onset (14 studies, 5733 participants; 1·85, 1·43-2·40, p<0·0001), higher risk of rapid cycling (eight studies, 3010 participants; 1·89, 1·45-2·48, p<0·0001), greater number of manic episodes (seven studies, 3909 participants; 1·26, 1·09-1·47, p=0·003), greater number of depressive episodes (eight studies, 4025 participants; 1·38, 1·07-1·79, p=0·013), and higher risk of suicide attempt (13 studies, 3422 participants; 2·25, 1·88-2·70, p<0·0001) compared with those with bipolar disorder without childhood maltreatment. Overall, these associations were not explained by publication bias, undue effects of individual studies, or variation in study quality.

INTERPRETATION

Childhood maltreatment predicts unfavourable clinical features and course of illness in patients with bipolar disorder.

FUNDING

None.

The role of life events and psychological factors in the onset of first and recurrent mood episodes in bipolar offspring: results from the Dutch Bipolar Offspring Study

BACKGROUND

Life events are an established risk factor for the onset and recurrence of unipolar and bipolar mood episodes, especially in the presence of genetic vulnerability. The dynamic interplay between life events and psychological context, however, is less studied. In this study, we investigated the impact of life events on the onset and recurrence of mood episodes in bipolar offspring, as well as the effects of temperament, coping and parenting style on this association.

METHOD

Bipolar offspring (n = 108) were followed longitudinally from adolescence to adulthood. Mood disorders were assessed with: the Kiddie Schedule of Affective Disorders and Schizophrenia - Present and Lifetime Version or the Structured Clinical Interview for DSM-IV Axis I disorders; life events with the Life Events and Difficulties Schedule; and psychological measures using the Utrecht Coping List, Temperament and Character Inventory and short-EMBU (memories of upbringing instrument). Anderson-Gill models (an extension of the Cox proportional hazard model) were utilized.

RESULTS

Life events were associated with an increased risk for first and, although less pronounced, subsequent mood episodes. There was a large confounding effect for the number of previous mood episodes; findings suggest a possible kindling effect. Passive coping style increased the risk of mood episode onset and recurrent episodes, but also altered the effect of life events on mood disorders. Harm avoidance temperament was associated with mood episode recurrence.

CONCLUSIONS

Life events are especially a risk factor in the onset of mood disorders, though less so in recurrent episodes. Psychological features (passive coping and harm-avoidant temperament) contribute to the risk of an episode occurring, and also have a moderating effect on the association between life events and mood episodes. These findings create potential early intervention strategies for bipolar offspring.

The impact of past direct-personal traumatic events on 12-month outcome in first episode psychotic mania: trauma and early psychotic mania

OBJECTIVE

Past traumatic events have been associated with poorer clinical outcomes in people with bipolar disorder. However, the impact of these events in the early stages of the illness remains unclear. The aim of this study was to investigate whether prior traumatic events were related to poorer outcomes 12 months following a first episode of psychotic mania.

METHODS

Traumatic events were retrospectively evaluated from patient files in a sample of 65 participants who had experienced first episode psychotic mania. Participants were aged between 15 and 28 years and were treated at a specialised early psychosis service. Clinical outcomes were measured by a variety of symptomatic and functioning scales at the 12-month time-point.

RESULTS

Direct-personal traumatic experiences prior to the onset of psychotic mania were reported by 48% of the sample. Participants with past direct-personal trauma had significantly higher symptoms of mania (p=0.02), depression (p=0.03) and psychopathology (p=0.01) 12 months following their first episode compared to participants without past direct-personal trauma, with medium to large effects observed. After adjusting for baseline scores, differences in global functioning (as measured by the Global Assessment of Functioning scale) were non-significant (p=0.05); however, participants with past direct-personal trauma had significantly poorer social and occupational functioning (p=0.04) at the 12-month assessment with medium effect.

CONCLUSIONS

Past direct-personal trauma may predict poorer symptomatic and functional outcomes after first episode psychotic mania. Limitations include that the findings represent individuals treated at a specialist early intervention centre for youth and the retrospective assessment of traumatic events may have been underestimated.

Predicting bipolar disorder on the basis of phenomenology: implications for prevention and early intervention

OBJECTIVE

Bipolar disorder is a multifaceted illness and there is often a substantial delay between the first onset of symptoms and diagnosis. Early detection has the potential to curtail illness progression and disorder-associated burden but it requires a clear understanding of the initial bipolar prodrome. This article summarizes the phenomenology of bipolar disorder with an emphasis on the initial prodrome, the evolution of the illness, and the implications for prevention and early intervention.

METHODS

A literature review was undertaken using Medline, Web of Science, and a hand search of relevant literature using keywords (e.g., phenomenology, initial or early symptoms, risk factors, and predictors/prediction). Findings from the literature were reviewed and synthesized and have been put into a clinical context.

RESULTS

Bipolar disorder is a recurrent, persistent, and disabling illness that typically develops in adolescence or early adulthood. The literature search yielded 28 articles, in which mood lability, nonspecific, non-mood symptoms, and cyclothymic temperament were the most cited prodromal features.

CONCLUSIONS

A small number of key prospective studies have provided evidence in support of an initial bipolar prodrome; however, methodological differences across studies have prohibited its clear delineation. It is, therefore, not currently possible to anticipate those who will develop bipolar disorder solely on the basis of early phenomenology. Accurate characterization of the bipolar disorder prodrome through high-quality, prospective research studies with adequate control groups will ultimately facilitate prompt and accurate diagnosis.

Modeling bipolar disorder suicidality

OBJECTIVES

To review the psychosocial, neuropsychological, and neurobiological evidence regarding suicide and bipolar disorder (BD), to enable the development of an integrated model that facilitates understanding, and to provide a useful framework for future research.

METHODS

A two-stage literature review was conducted. First, an electronic literature search was performed using key words (e.g., bipolar disorder, suicide risk, and neuroimaging) and standard databases (e.g., MEDLINE). Second, theoretical suicide models were reviewed, and their evidence base and relevance to BD were evaluated in order to determine a guiding theoretical framework for contextualizing suicide in BD.

RESULTS

Although accumulating clinical, cognitive, and neurobiological correlates of suicide have been identified in BD, extant research has been largely atheoretical. The Cry of Pain (CoP) and an adapted version of the model, the Schematic Appraisals Model of Suicide (SAMS), provide a useful schema for examining vulnerability to suicide in BD, by taking into account biopsychosocial determinants of suicidality. In combination, these also provide a model within which the neural correlates of suicide can be integrated.

CONCLUSIONS

The proposed Bipolar Suicidality Model (BSM) highlights the psychosocial precursors to suicidality in BD, while recognizing the key role of cognitive deficits and underlying functional neurobiological abnormalities. It usefully integrates our knowledge, and provides a novel perspective that is intended to meaningfully inform future research initiatives, and can lead to a better understanding of suicidality in bipolar disorder. Ultimately, it is hoped that it will facilitate the development of targeted interventions that diminish the risk of suicide in bipolar disorder.

The impact of childhood trauma on cognitive functioning in patients recently recovered from a first manic episode: data from the Systematic Treatment Optimization Program for Early Mania (STOP-EM)

BACKGROUND

Both bipolar disorder (BD) and childhood trauma are associated with cognitive impairment. People with BD have high rates of childhood trauma, which confer greater overall disease severity, but, it is unknown if childhood trauma is associated with greater neurocognitive impairment in BD patients early in the course of their illnesses. In this study, we investigated the impact of childhood trauma on specific cognitive dysfunction in patients who recently recovered from their first episode of mania.

METHODS

Data were available for 64 patients and 28 healthy subjects matched by age, gender and pre-morbid IQ, recruited from a large university medical center. History of childhood trauma was measured using the Childhood Trauma Questionnaire. Cognitive function was assessed through a comprehensive neuropsychological test battery.

RESULTS

Trauma was associated with poorer cognitive performance in patients on cognitive measures of IQ, auditory attention and verbal and working memory, and a different pattern was observed in healthy subjects.

LIMITATIONS

We had a modest sample size, particularly in the group of healthy subjects with trauma.

CONCLUSIONS

Childhood trauma was associated with poorer cognition in BD patients who recently recovered from a first episode of mania compared to healthy subjects. The results require replication, but suggest that the co-occurrence of trauma and bipolar disorder can affect those cognitive areas that are already more susceptible in patients with BD.

Schema therapy for bipolar disorder: a conceptual model and future directions

Schema therapy (ST) is an integrative form of psychotherapy developed for complex, chronic psychological disorders with a characterlogical underpinning. Bipolar disorder is just such a disorder--complex and often comorbid, with demonstrated stable cognitive and personality features that complicate the course of illness. This article presents the reasons justifying the application of ST to bipolar disorder and proposes a treatment rationale and future directions for treatment and research. If well adapted to the characteristics of bipolar disorder, ST might prove to be an effective adjunctive psychotherapy option that attenuates emotional reactivity, reduces symptoms and improves quality of life.

Different stressors, different strategies, different outcomes: how domain-specific stress responses differentially predict depressive symptoms among adolescents

As a time of notably increased stress and a marked rise in depressive symptoms, adolescence is a key period in which to examine how stress is related to mental health outcomes. Many studies examine stress as a unitary construct; however, research suggests that how adolescents respond to stress within different domains may differentially predict depression. The current study used an 8-week weekly diary design to assess how adolescents' cognitive appraisals, rumination, and co-rumination in response to dependent, independent, social, and nonsocial stressors differentially predicted depressive symptoms. Participants were 111 high school students (72% female) ages 14-19 years (mean age 16.4). Results indicated that rumination and co-rumination about dependent and social events, rather than independent or nonsocial events, prospectively predicted depressive symptoms. Negative cognitive appraisals prospectively predicted depressive symptoms regardless of domain. This study provides support for the hypothesis that adolescents' responses to stress in different domains differentially predict depressive symptoms.

Childhood maltreatment and clinical outcomes of bipolar disorder

OBJECTIVE

Adverse life events, especially early trauma, play a major role in the course and expression of bipolar disorder (BD). The aim of this article is to present a systematic review about the impact of childhood trauma on the clinical course of BD.

METHOD

A computer-aided search was performed in Medline, ISI database, EMBASE, PsychInfo, Centre for Reviews and Dissemination, and Databases of Thomson Reuters at April 2011, supplemented by works identified from the reference lists of the first selected papers. Two investigators systematically and independently examined all articles, selecting those according inclusion and exclusion criteria.

RESULTS

Four hundred fifteen articles were identified, of which 19 remained in the review after exclusion criteria were applied. In general, childhood maltreatment predicted worsening clinical course of BD. After assessing the quality of the data and of the measurements, childhood maltreatment can be strongly associated to early onset of disorder, suicidality, and substance abuse disorder in patients with BD.

CONCLUSION

Data suggest that childhood abuse and neglect are risk factors associated with worsening clinical course of BD. The conclusions should be interpreted with caution because all the studies included are cross-sectional and the majority are showing inconsistencies regarding childhood trauma as independent variable and how it is assessed.

Disruption of the neuregulin 1 gene in the rat alters HPA axis activity and behavioral responses to environmental stimuli

Exposure to stress can result in an increased risk for psychiatric disorders, especially among genetically predisposed individuals. Neuregulin 1 (NRG1) is a susceptibility gene for schizophrenia and is also associated with psychotic bipolar disorder. In the rat, the neurons of the hypothalamic paraventricular nucleus show strong expression of Nrg1 mRNA. In patients with schizophrenia, a single nucleotide polymorphism in the 5' region of NRG1 interacts with psychosocial stress to affect reactivity to expressed emotion. However, there is virtually no information on the role of NRG1 in hypothalamic-pituitary-adrenal axis function, and whether the protein is expressed in the paraventricular nucleus is unknown. The present studies utilize a unique line of Nrg1 hypomorphic rats (Nrg1(Tn)) generated by gene trapping with the Sleeping Beauty transposon. We first established that the Nrg1(Tn) rats displayed reduced expression of both the mRNA and protein corresponding to the Type II NRG1 isoform. After confirming, using wild type animals, that Type II NRG1 is expressed in the neurocircuitry involved in regulating hypothalamic-pituitary-adrenal axis responses to environmental stimuli, the Nrg1(Tn) rats were then used to test the hypothesis that altered expression of Type II NRG1 disrupts stress regulation and reactivity. In support of this hypothesis, Nrg1(Tn) rats have disrupted basal and acute stress recovery corticosterone secretion, differential changes in expression of glucocorticoid receptors in the pituitary, paraventricular nucleus and hippocampus, and a failure to habituate to an open field. Together, these findings point to NRG1 as a potential novel regulator of neuroendocrine responses to stress as well as behavioral reactivity.

Sex-specific neuroendocrine and behavioral phenotypes in hypomorphic Type II Neuregulin 1 rats

Neuregulin 1 (NRG1) is an important growth factor involved in the development and plasticity of the central nervous system. Since its identification as a susceptibility gene for schizophrenia, several transgenic mouse models have been employed to elucidate the role NRG1 may play in the pathogenesis of psychiatric disease. Unfortunately very few studies have included females, despite the fact that some work suggests that the consequences of disrupted NRG1 expression may be sex-specific. Here, we used Nrg1 hypomorphic (Nrg1(Tn)) Fischer rats to demonstrate sex-specific changes in neuroendocrine and behavioral phenotypes as a consequence of reduced Type II NRG1 expression. We have previously shown that male Nrg1(Tn) rats have increased basal corticosterone levels, and fail to habituate to an open field despite normal overall levels of locomotor activity. The current studies show that, in contrast, female Nrg1(Tn) rats exhibit enhanced suppression of corticosterone levels following an acute stress, reduced locomotor activity, and enhanced habituation to novel environments. Furthermore, we also show that female, but not male, Nrg1(Tn) rats have impaired prepulse inhibition. Finally, we provide evidence that sex-specific changes are not likely attributable to major disruptions in the hypothalamic-pituitary-gonadal axis, as measures of pubertal onset, estrous cyclicity, and reproductive capacity were unaltered in female Nrg1(Tn) rats. Our results provide further support for both the involvement of NRG1 in the control of hypothalamic-pituitary-adrenal axis function and the sex-specific nature of this relationship.

Life stress and kindling in bipolar disorder: review of the evidence and integration with emerging biopsychosocial theories

Most life stress literature in bipolar disorder (BD) fails to account for the possibility of a changing relationship between psychosocial context and episode initiation across the course of the disorder. According to Post's (1992) influential kindling hypothesis, major life stress is required to trigger initial onsets and recurrences of affective episodes, but successive episodes become progressively less tied to stressors and may eventually occur autonomously. Subsequent research on kindling has largely focused on unipolar depression (UD), and the model has been tested in imprecise and inconsistent ways. The aim of the present paper is to evaluate evidence for the kindling model as it applies to BD. We first outline the origins of the hypothesis, the evidence for the model in UD, and the issues needing further clarification. Next, we review the extant literature on the changing relationship between life stress and bipolar illness over time, and find that evidence from the methodologically strongest studies is inconsistent with the kindling hypothesis. We then integrate this existing body of research with two emerging biopsychosocial models of BD: the Behavioral Approach System dysregulation model, and the circadian and social rhythm theory. Finally, we present therapeutic implications and suggestions for future research.

Generation of life events in bipolar spectrum disorders: a re-examination and extension of the stress generation theory

The extent to which stress generation occurs in bipolar spectrum disorders (BSD) is not well understood. The present study examined whether 75 BSD participants experienced elevated rates of behavior-dependent life events, as compared with 38 normal control participants. Within the BSD group, we also examined whether depressive or hypomanic symptoms prospectively predicted increases in various types of negative and positive life events. Results indicated that BSD participants experienced overall increases in behavior-dependent events over the follow-up, as compared with normal controls. At the symptom level, the event generation process occurred in more specific event domains. Results suggest that the stress generation theory of unipolar depression can be extended to BSD and that the type of generated events may be polarity-specific.

Early life stressors and genetic influences on the development of bipolar disorder: the roles of childhood abuse and brain-derived neurotrophic factor

OBJECTIVES

Although there is increasing research exploring the psychosocial influences and biological underpinnings of bipolar disorder, relatively few studies have specifically examined the interplay between these factors in the development of this illness. Social-biological models within a developmental psychopathology perspective are necessary to advance our understanding of the processes involved in the onset and course of bipolar disorder. This article presents a review of the empirical literature linking childhood abuse to bipolar disorder, the research to date on the possible role of brain-derived neurotrophic factor (BDNF) in the development of this disorder, followed by a discussion of how childhood abuse may interact with BDNF.

METHODS

A literature search was conducted using Psycinfo to identify relevant articles on childhood abuse, BDNF, and bipolar disorder.

RESULTS

The extant research implicates both childhood abuse and BDNF in the etiology of bipolar disorder. Specifically, there is growing evidence associating early abuse to the development of bipolar disorder. Similarly, the BDNF Val66 allele has been linked with increased susceptibility to bipolar disorder. Based on existing research, a genetic diathesis-transactional stress model is proposed incorporating childhood abuse and the BDNF gene in the pathogenesis of bipolar disorder.

CONCLUSIONS

Although there is some support for this model, the relatively modest amount of relevant literature highlights the need for further research. An integrative theoretical framework including both social and biological processes in bipolar disorder is important for the development of effective prevention and treatment strategies for this disorder.

Stress generation in depression: A systematic review of the empirical literature and recommendations for future study

Within the past 20 years, depression research has given increasing consideration to the possibility of complex and reciprocal relations between stress and depression. Not only does stress increase risk for depression (i.e., a stress exposure model of depression), but depression, or depressogenic vulnerabilities, in turn, also increases susceptibility to stressful events that are at least in part influenced by the individual (i.e., stress generation; Hammen, 1991). The present review provides a systematic examination of the stress generation literature to date, with specific focus given to depression and depressogenic risk factors (i.e., past stress, negative cognitive styles, and personality and interpersonal vulnerabilities) as predictors of the stress generation effect, as well as gender differences in stress generation, the sequelae of generated stress, and the relative specificity of this phenomenon to depression. The research thus far appears most consistent in supporting the role of depression in predicting generated stress, although more research is still required. In addition to highlighting these findings, methodological limitations and conceptual gaps in the literature are discussed with the view of informing future research in this area.

Chronic stress and stressful life events in the offspring of parents with bipolar disorder

BACKGROUND

The stress generation theory suggests that depressed individuals and children of depressed mothers are prone to create stressors that are interpersonal and dependent on their own behaviour. Exposure to "self-generated" stress is believed to increase the risk for onset and recurrence of depression. Much less is known about stress in the offspring of parents with bipolar disorder (OBD).

METHODS

As part of a longitudinal study, 37 OBD and 33 offspring of parents with no affective disorder (13 to 26 years old) were interviewed using the UCLA Life Stress Interview, assessing their current life circumstances (chronic stress) and recent negative life events (episodic stress).

RESULTS

The OBD reported more difficulties in interpersonal and non-interpersonal domains of chronic stress than controls. The group differences remained significant after controlling for the presence of affective disorders, indicating that the effect of risk status on chronic stress is independent of the problems associated with having a disorder. With respect to episodic stress, the OBD were 3.9 times more likely to have experienced a moderate to severe interpersonal stressor compared to the control group. There was no group difference for dependent events, but the OBD experienced more severe independent events than controls.

LIMITATIONS

Methodological limitations include a small sample size, large age range, and the absence of parent-reported stress and symptomatology.

CONCLUSIONS

Although the findings do not support the stress generation theory, they suggest that elevated levels of episodic and chronic stress may be important markers of risk for affective disorders in high-risk participants.