Neurobiological and behavioural studies of affective instability in clinical populations: a systematic review

A Dimensional Approach to Emotional Lability in Youth

Emotional lability (EL) is a common symptom dimension in youth. It manifests in the context of a number of psychiatric illnesses and is a promising transdiagnostic construct that is recognizable and treatable and warrants further study. Multiple terms and assessment tools exist to define and measure EL, and it has a phenomenology distinct from the related construct of irritability. This clinical perspective reviews the neurobiological and clinical evidence in support of EL as an important symptom dimension that responds to a variety of behavioral and medication interventions and highlights the significant limitations of this approach.

Pharmacologic and Non-Pharmacologic Interventions for Emotional Lability: A Meta-Analysis

Emotional Lability (EL) is a common symptom dimension in a variety of psychiatric disorders. However, as it is not typically a diagnosis in its own right, it lacks a consistently applied clinical definition and treatment approach. Therefore, in this review we performed a meta-analysis to determine the effect size for treatments of EL across diagnostic categories. We then conducted subgroup analyses to compare effect sizes for pharmacologic (MED) and behavioral (BEH) treatments, according to underlying diagnosis, and according to medication class. We found that pharmacologic and non-pharmacologic treatments are effective for EL, and that the effect sizes were similar - a finding with implications for clinical practice. Our finding also supports future research which approaches EL as an important construct independent of underlying diagnosis.

The shared genetic basis of mood instability and psychiatric disorders: A cross-trait genome-wide association analysis

Recent genome-wide association studies of mood instability (MOOD) have found significant positive genetic correlation with major depression (DEP) and weak correlations with other psychiatric disorders. We investigated the polygenic overlap between MOOD and psychiatric disorders beyond genetic correlation to better characterize putative shared genetic determinants. GWAS summary statistics for schizophrenia (SCZ, n = 105,318), bipolar disorder (BIP, n = 413,466), DEP (n = 450,619), attention-deficit hyperactivity disorder (ADHD, n = 53,293), and MOOD (n = 363,705) were analyzed using the bivariate causal mixture model and conjunctional false discovery rate methods. MOOD correlated positively with all psychiatric disorders, but with wide variation in strength (r_g  = 0.10-0.62). Of 10.4 K genomic variants influencing MOOD, 4 K-9.4 K influenced psychiatric disorders. Furthermore, MOOD was jointly associated with DEP at 163 loci, SCZ at 110, BIP at 60 and ADHD at 25. Fifty-three jointly associated loci were overlapping across two or more disorders, seven of which had discordant effect directions on psychiatric disorders. Genes mapped to loci associated with MOOD and all four disorders were enriched in a single gene-set, "synapse organization." The extensive polygenic overlap indicates shared molecular underpinnings across MOOD and psychiatric disorders. However, distinct patterns of genetic correlation and effect directions may relate to differences in the core clinical features of each disorder.

Mobile footprinting: linking individual distinctiveness in mobility patterns to mood, sleep, and brain functional connectivity

Mapping individual differences in behavior is fundamental to personalized neuroscience, but quantifying complex behavior in real world settings remains a challenge. While mobility patterns captured by smartphones have increasingly been linked to a range of psychiatric symptoms, existing research has not specifically examined whether individuals have person-specific mobility patterns. We collected over 3000 days of mobility data from a sample of 41 adolescents and young adults (age 17-30 years, 28 female) with affective instability. We extracted summary mobility metrics from GPS and accelerometer data and used their covariance structures to identify individuals and calculated the individual identification accuracy-i.e., their "footprint distinctiveness". We found that statistical patterns of smartphone-based mobility features represented unique "footprints" that allow individual identification (p < 0.001). Critically, mobility footprints exhibited varying levels of person-specific distinctiveness (4-99%), which was associated with age and sex. Furthermore, reduced individual footprint distinctiveness was associated with instability in affect (p < 0.05) and circadian patterns (p < 0.05) as measured by environmental momentary assessment. Finally, brain functional connectivity, especially those in the somatomotor network, was linked to individual differences in mobility patterns (p < 0.05). Together, these results suggest that real-world mobility patterns may provide individual-specific signatures relevant for studies of development, sleep, and psychopathology.

Affective Instability, Depression, and Anxiety Symptoms in a Community Sample of Pregnant and Postpartum Women: A Cross-Sectional Study

BACKGROUND

Although perinatal women experience an elevated level of affective instability (AI), limited research has been conducted to examine perinatal AI and its relation to depression and anxiety. The current study investigated correlations between AI and depression, between AI and anxiety during the perinatal period, and between current depression and anxiety and the latent factors of the Affective Lability Scale-18 (ALS-18).

METHODS

202 Canadian perinatal women participated in this cross-sectional study. The ALS-18 was used to assess AI, while the Depression, Anxiety, and Stress Scale-21 measured depression, anxiety, and stress. Multiple logistic regression was performed to investigate the relationship between AI and depression and anxiety, and multiple linear regression was conducted to examine the association between current depression and anxiety and the three latent factors of ALS-18.

RESULTS

The findings revealed a significant association between AI and depression and between AI and anxiety. Current depression and anxiety were correlated with ALS-18 factors of depression/anxiety shift and depression/elation shift, while current depression was linked to ALS-18 factor of anger.

CONCLUSIONS

The study findings have important implications for early detection and intervention of maternal anxiety and depression. In order to improve maternal mental health, AI should be included in routine perinatal check-ups.

Recruiting and exploring vulnerabilities among young people at risk, or in the early stages of serious mental illness (borderline personality disorder and first episode psychosis)

INTRODUCTION

Many gaps exist in our understanding of the developmental pathways to severe mental illness (SMI), including borderline personality disorder (BPD) and psychosis. However, those who have experienced adverse childhood experiences (ACEs) are at an increased risk and there is evidence to suggest that one of the earliest markers is emotional dysregulation. An area which has received relatively less research attention is the role neurodevelopmental disorders (NDDs) play. The aim of this feasibility study was therefore to explore the clinical profiles of young people early in the course of SMI, including their profiles of ACEs, emotional regulation difficulties, borderline personality traits and NDDs.

METHODS

A cross-sectional study of young people (aged 15-25) at risk of SMI, currently being seen within NHS mental health services, was conducted. This included those with early symptoms of psychosis and/or BPD as assessed by diagnostic interview. Eligible participants self-completed a battery of sociodemographic, clinical, and psychological measures in the company of a researcher. This included assessments of: symptoms of NDDs; borderline pathology traits; ACEs; and difficulties in emotional regulation. Statistical analyses included Mann-Whitney U tests and multiple regression.

RESULTS

Of the 118 potentially eligible participants who were referred, 48 were ultimately included in the study. Young people early in the course of SMI reported a high prevalence of ACEs and deficits in emotional regulation. In total, 79% met criteria for attention deficit hyperactivity disorder (ADHD) and/or autism spectrum disorder (ASD). Emotional dysregulation was found to significantly mediate the association between both ACEs and the frequency of NDDs and borderline personality traits, however given the small sample size these results are preliminary in nature.

CONCLUSION

Young people early in the course of SMI are at an increased risk of experiencing multiple childhood adversities and our results indicate a high prevalence of NDDs amongst them. Emotional dysregulation emerged as a potentially significant early marker of future clinical severity. We suggest that the clinical implications of our findings include routine screening for NDDs and ACEs and an increased recognition of the significance of emotional dysregulation. However, larger scale longitudinal studies are needed to investigate these preliminary findings further.

Characterization of affective lability across subgroups of psychosis spectrum disorders

BACKGROUND

Affective lability is elevated and associated with increased clinical burden in psychosis spectrum disorders. The extent to which the level, structure and dispersion of affective lability varies between the specific disorders included in the psychosis spectrum is however unclear. To have potential value as a treatment target, further characterization of affective lability in these populations is necessary. The main aim of our study was to investigate differences in the architecture of affective lability in different psychosis spectrum disorders, and if putative differences remained when we controlled for current symptom status.

METHODS

Affective lability was measured with The Affective Lability Scale Short Form (ALS-SF) in participants with schizophrenia (SZ, n = 76), bipolar I disorder (BD-I, n = 105), bipolar II disorder (BD-II, n = 68) and a mixed psychosis-affective group (MP, n = 48). Multiple analyses of covariance were conducted to compare the ALS-SF total and subdimension scores of the diagnostic groups, correcting for current psychotic, affective and anxiety symptoms, substance use and sex. Double generalized linear models were performed to compare the dispersion of affective lability in the different groups.

RESULTS

Overall group differences in affective lability remained significant after adjusting for covariates (p = .001). BD-II had higher affective lability compared to SZ and BD-I (p = .004), with no significant differences between SZ and BD-I. There were no significant differences in the contributions of ALS-SF dimensions to the total affective lability or in dispersion of affective lability between the groups.

CONCLUSIONS

This study provides the construct of affective lability in psychosis spectrum disorders with more granular details that may have implications for research and clinical care. It demonstrates that despite overlap in core symptom profiles, BD-I is more similar to SZ than it is to BD-II concerning affective lability and the BD groups should consequently be studied apart. Further, affective lability appears to be characterized by fluctuations between depressive- and other affective states across different psychosis spectrum disorders, indicating that affective lability may be related to internalizing problems in these disorders. Finally, although the level varies between groups, affective lability is evenly spread and not driven by extremes across psychosis spectrum disorders and should be assessed irrespective of diagnosis.

Neural reward circuit dysfunction as a risk factor for bipolar spectrum disorders and substance use disorders: A review and integration

Bipolar spectrum disorders (BSDs) and substance use disorders (SUDs) are associated with neural reward dysfunction. However, it is unclear what pattern of neural reward function underlies pre-existing vulnerability to BSDs and SUDs, or whether neural reward function explains their high co-occurrence. The current paper provides an overview of the separate literatures on neural reward sensitivity in BSDs and SUDs. We provide a systematic review of 35 studies relevant to identifying neural reward function vulnerability to BSDs and SUDs. These studies include those examining neural reward processing on a monetary reward task with prospective designs predicting initial onset of SUDs, familial risk studies that examine unaffected offspring or first-degree relatives of family members with BSDs or SUDs, and studies that examine individuals with BSDs or SUDs who are not currently in an episode of the disorder. Findings from the review highlight that aberrant responding and connectivity across neural regions associated with reward and cognitive control confers risk for the development of BSDs and SUDs. Discussion focuses on limitations of the extant literature. We conclude with an integration and theoretical model for understanding how aberrant neural reward responding may constitute a vulnerability to the development of both BSDs and SUDs.

Emotional dysregulation in adults: The influence of rumination and negative secondary appraisals of emotion

BACKGROUND

Emotional dysregulation is commonly discussed as a transdiagnostic factor in clinical populations. The present study aims to investigate cognitive factors (rumination and negative appraisals of emotion) in the maintenance of emotional dysregulation in a normative sample in order to partially validate a cognitive model of emotional dysregulation and to examine the potential clinical relevance of addressing cognitive factors in the treatment of emotional dysregulation.

METHODS

People who were 18 or older were asked to participate via a university research system and social media. Participants (N = 216) were asked to fill out online surveys regarding emotional dysregulation, rumination and negative secondary appraisals of emotion.

RESULTS

People who had higher emotional dysregulation levels displayed a greater tendency to ruminate and were more prone to negative secondary appraisals of emotion. There was a positive association between rumination and negative secondary appraisals of emotion, and this association was mediated by emotional dysregulation.

LIMITATIONS

The present study was solely based on self-report measurements and the collected data were cross-sectional.

CONCLUSIONS

The present study showed that a wide spectrum of experiences of emotional dysregulation occurred in a normative sample. The significant mediation highlighted the maintaining role of rumination and negative appraisals in emotional dysregulation. These data highlight the importance of addressing cognitive factors in emotional dysregulation.

Single-Dose Effects of Citalopram on Neural Responses to Affective Stimuli in Borderline Personality Disorder: A Randomized Clinical Trial

BACKGROUND

Psychiatric medication that has a soothing effect on limbic responses to affective stimuli could improve affective instability symptoms as observed in borderline personality disorder (BPD). The objective of this study was to investigate whether citalopram versus placebo reduces the response of the affective neural circuitry during an emotional challenge.

METHODS

A total of 30 female individuals with a BPD diagnosis participated in a placebo-controlled, double-blind crossover trial design. Three hours after oral drug intake, individuals with BPD viewed affective pictures while undergoing functional magnetic resonance imaging. Blood oxygen level-dependent responses to images of negative affective scenes and faces showing negative emotional expressions were assessed in regions of interest (amygdala, anterior cingulate cortex, anterior insula, dorsolateral prefrontal cortex). Blood perfusion at rest was assessed with arterial spin labeling.

RESULTS

The neural response to pictures showing negative affective scenes was not significantly affected by citalopram (n = 23). Citalopram significantly reduced the amygdala response to pictures of faces with negative affective expressions (n = 25, treatment difference left hemisphere: -0.06 ± 0.16, p < .05; right hemisphere: -0.06 ± 0.17, p < .05). We observed no significant effects of citalopram on the other regions. The drug did not significantly alter blood perfusion at rest.

CONCLUSIONS

Citalopram can alter the amygdala response to affective stimuli in BPD, which is characterized by overly responsive affective neural circuitry.

Heterogeneity and Classification of Recent Onset Psychosis and Depression: A Multimodal Machine Learning Approach

Diagnostic heterogeneity within and across psychotic and affective disorders challenges accurate treatment selection, particularly in the early stages. Delineation of shared and distinct illness features at the phenotypic and brain levels may inform the development of more precise differential diagnostic tools. We aimed to identify prototypes of depression and psychosis to investigate their heterogeneity, with common, comorbid transdiagnostic symptoms. Analyzing clinical/neurocognitive and grey matter volume (GMV) data from the PRONIA database, we generated prototypic models of recent-onset depression (ROD) vs. recent-onset psychosis (ROP) by training support-vector machines to separate patients with ROD from patients with ROP, who were selected for absent comorbid features (pure groups). Then, models were applied to patients with comorbidity, ie, ROP with depressive symptoms (ROP+D) and ROD participants with sub-threshold psychosis-like features (ROD+P), to measure their positions within the affective-psychotic continuum. All models were independently validated in a replication sample. Comorbid patients were positioned between pure groups, with ROP+D patients being more frequently classified as ROD compared to pure ROP patients (clinical/neurocognitive model: χ2 = 14.874; P < .001; GMV model: χ2 = 4.933; P = .026). ROD+P patient classification did not differ from ROD (clinical/neurocognitive model: χ2 = 1.956; P = 0.162; GMV model: χ2 = 0.005; P = .943). Clinical/neurocognitive and neuroanatomical models demonstrated separability of prototypic depression from psychosis. The shift of comorbid patients toward the depression prototype, observed at the clinical and biological levels, suggests that psychosis with affective comorbidity aligns more strongly to depressive rather than psychotic disease processes. Future studies should assess how these quantitative measures of comorbidity predict outcomes and individual responses to stratified therapeutic interventions.

Brain imaging features in schizophrenia with co-occurring auditory verbal hallucinations and depressive symptoms-Implication for novel therapeutic strategies to alleviate the reciprocal deterioration

BACKGROUND

Auditory verbal hallucinations (AVHs) and depressive symptoms are highly prevalent in schizophrenia, and recent progress has been made in understanding the reciprocal deterioration of both symptoms through structural and functional brain imaging studies. To date, there is limited literature on this topic. In this review, we synthesized the recent literature on the neuroimaging features of schizophrenia patients with concurrent AVHs and depressive symptoms.

METHODS

A literature search was conducted with the major databases using the keywords, mainly including schizophrenia, AVHs, depression, neuropsychiatric disorders, brain imaging, and magnetic resonance imaging.

RESULTS

The existing studies have shown that AVHs and depressive symptoms reciprocally deteriorate in patients with schizophrenia, which has challenged the conventional treatment of the disease. Interestingly, repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) therapies have emerged as two efficacious brain stimulation treatments that can normalize the brain regions associated with the symptoms, as shown through functional and structural brain imaging studies. In light of these important findings, there is an urgent need to conduct in-depth neuronal mechanistic studies to identify targets for stimulation therapy.

CONCLUSIONS

These new findings may elucidate the pathological mechanisms underlying schizophrenia with concurrent AVHs and depressive symptoms. Furthermore, this review has important clinical implications for developing novel therapeutic strategies to alleviate the reciprocal deterioration AVHs and depressive symptoms of schizophrenia patients.

Clinical Features, Neuropsychology and Neuroimaging in Bipolar and Borderline Personality Disorder: A Systematic Review of Cross-Diagnostic Studies

Background: Bipolar Disorder (BD) and Borderline Personality Disorder (BPD) have clinically been evolving as separate disorders, though there is still debate on the nosological valence of both conditions, their interaction in terms of co-morbidity or disorder spectrum and their distinct pathophysiology. Objective: The objective of this review is to summarize evidence regarding clinical features, neuropsychological performance and neuroimaging findings from cross-diagnostic studies comparing BD and BPD, to further caracterize their complex interplay. Methods: Using PubMed, PsycINFO and TripDataBase, we conducted a systematic literature search based on PRISMA guidelines of studies published from January 1980 to September 2019 which directly compared BD and BPD. Results: A total of 28 studies comparing BD and BPD were included: 19 compared clinical features, 6 neuropsychological performance and three neuroimaging abnormalities. Depressive symptoms have an earlier onset in BPD than BD. BD patients present more mixed or manic symptoms, with BD-I differing from BPD in manic phases. BPD patients show more negative attitudes toward others and self, more conflictive interpersonal relationships, and more maladaptive regulation strategies in affective instability with separate pathways. Impulsivity seems more a trait in BPD rather than a state as in BD. Otherwise, BD and BPD overlap in depressive and anxious symptoms, dysphoria, various abnormal temperamental traits, suicidal ideation, and childhood trauma. Both disorders differ and share deficits in neuropsychological and neuroimaging findings. Conclusion: Clinical data provide evidence of overlapping features in both disorders, with most of those shared symptoms being more persistent and intense in BPD. Thus, categorical classifications should be compared to dimensional approaches in transdiagnostic studies investigating BPD features in BD regarding their respective explanatory power for individual trajectories. Systematic Review Registration: The search strategy was pre-registered in PROSPERO: CRD42018100268.

Explaining why childhood abuse is a risk factor for poorer clinical course in bipolar disorder: a path analysis of 923 people with bipolar I disorder

BACKGROUND

Childhood abuse is a risk factor for poorer illness course in bipolar disorder, but the reasons why are unclear. Trait-like features such as affective instability and impulsivity could be part of the explanation. We aimed to examine whether childhood abuse was associated with clinical features of bipolar disorder, and whether associations were mediated by affective instability or impulsivity.

METHODS

We analysed data from 923 people with bipolar I disorder recruited by the Bipolar Disorder Research Network. Adjusted associations between childhood abuse, affective instability and impulsivity and eight clinical variables were analysed. A path analysis examined the direct and indirect links between childhood abuse and clinical features with affective instability and impulsivity as mediators.

RESULTS

Affective instability significantly mediated the association between childhood abuse and earlier age of onset [effect estimate (θ)/standard error (SE): 2.49], number of depressive (θ/SE: 2.08) and manic episodes/illness year (θ/SE: 1.32), anxiety disorders (θ/SE: 1.98) and rapid cycling (θ/SE: 2.25). Impulsivity significantly mediated the association between childhood abuse and manic episodes/illness year (θ/SE: 1.79), anxiety disorders (θ/SE: 1.59), rapid cycling (θ/SE: 1.809), suicidal behaviour (θ/SE: 2.12) and substance misuse (θ/SE: 3.09). Measures of path analysis fit indicated an excellent fit to the data.

CONCLUSIONS

Affective instability and impulsivity are likely part of the mechanism of why childhood abuse increases risk of poorer clinical course in bipolar disorder, with each showing some selectivity in pathways. They are potential novel targets for intervention to improve outcome in bipolar disorder.

Toi Même, a Mobile Health Platform for Measuring Bipolar Illness Activity: Protocol for a Feasibility Study

BACKGROUND

The diagnosis and management of bipolar disorder are limited by the absence of available biomarkers. Patients with bipolar disorder frequently present with mood instability even during remission, which is likely associated with the risk of relapse, impaired functioning, and suicidal behavior, indicating that the illness is active.

OBJECTIVE

This research protocol aimed to investigate the correlations between clinically rated mood symptoms and mood/behavioral data automatically collected using the Toi Même app in patients with bipolar disorder presenting with different mood episodes. This study also aimed to assess the feasibility of this app for self-monitoring subjective and objective mood/behavior parameters in those patients.

METHODS

This open-label, nonrandomized trial will enroll 93 (31 depressive, 31 euthymic, and 31 hypomanic) adults diagnosed with bipolar disorder type I/II (Diagnostic and Statistical Manual of Mental Disorders, 5th edition criteria) and owning an iPhone. Clinical evaluations will be performed by psychiatrists at the baseline and after 2 weeks, 1 month, 2 months, and 3 months during the follow-up. Rather than only accessing the daily mood symptoms, the Toi Même app also integrates ecological momentary assessments through 2 gamified tests to assess cognition speed (QUiCKBRAIN) and affective responses (PLAYiMOTIONS) in real-life contexts, continuously measures daily motor activities (eg, number of steps, distance) using the smartphone's motion sensors, and performs a comprehensive weekly assessment.

RESULTS

Recruitment began in April 2018 and the completion of the study is estimated to be in December 2021. As of April 2019, 25 participants were enrolled in the study. The first results are expected to be submitted for publication in 2020. This project has been funded by the Perception and Memory Unit of the Pasteur Institute (Paris) and it has received the final ethical/research approvals in April 2018 (ID-RCB: 2017-A02450-53).

CONCLUSIONS

Our results will add to the evidence of exploring other alternatives toward a more integrated approach in the management of bipolar disorder, including digital phenotyping, to develop an ethical and clinically meaningful framework for investigating, diagnosing, and treating individuals at risk of developing bipolar disorder or currently experiencing bipolar disorder. Further prospective studies on the validity of automatically generated smartphone data are needed for better understanding the longitudinal pattern of mood instability in bipolar disorder as well as to establish the reliability, efficacy, and cost-effectiveness of such an app intervention for patients with bipolar disorder.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03508427; https://clinicaltrials.gov/ct2/show/NCT03508427.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/18818.

Diffusion tensor imaging in borderline personality disorder showing prefrontal white matter alterations

Borderline personality disorder (BPD) has repeatedly been linked to alterations in fronto-limbic dysfunction. In this study, we tested the hypothesis of disturbed structural connectivity in underlying fibre tracts and their relation to symptom profiles. We analysed diffusion tensor imaging (DTI) data from 18 female BPD patients and 38 female healthy controls. Group comparisons showed significant (p < .05, FDR adjusted) increase of radial diffusivity (RD) in the right frontal lobe, including the uncinate fasciculus, anterior thalamic radiation, and inferior fronto-occipital fasciculus, as well as overall apparent diffusion coefficient (ADC) increases in the anterior and posterior internal capsule. Symptom correlations, based on the BSL-95 questionnaires, within the BPD sample showed significant negative correlations of dysphoria with ADC the left and right anterior thalamic radiation, and positive correlations of fractional anisotropy with self-perception scores in the right superior corona radiata. While our findings add to the fronto-limbic dysfunction model of BPD, they provide additional evidence of links to its affective core pathology, particularly frontotemporal and fronto-thalamic systems.

The Emerging Neurobiology of Bipolar Disorder

(Reprinted with permission from Trends in Neurosciences, January 2018, Vol. 41, No. 1 ).

Mood instability during pregnancy and postpartum: a systematic review

Perinatal mood instability (MI) is a common clinical observation in perinatal women, and existing research indicates that MI is strongly associated with a variety of mental disorders. The purpose of this study is to review the evidence of perinatal MI systematically, with a focus on perinatal MI, its relation to perinatal depression, and its effects on children. A systematic search of the literature using PRISMA guidelines was conducted on seven academic health databases to identify any peer-reviewed articles published in English from 1985 to July 2017. Studies were screened, data were extracted, and quality of the selected studies was assessed. A total of 1927 abstracts were returned from the search, with 1063 remaining for abstract screening after duplicate removal, and 4 quantitative studies were selected for final analysis. The selected studies addressed perinatal MI (n = 2), the relation of perinatal MI to perinatal depression (n = 1), and the effects of perinatal MI on children (n = 1). The selected studies identified that perinatal women experienced a significantly higher level of MI than non-perinatal women, MI is a prominent feature in perinatal women with and without depression, mood lability during the early postpartum predicts psychopathology up to 14 months postpartum, and maternal emotion dysregulation, rather than maternal psychopathology, increases the risk of heightened facial affect synchrony in mother-infant interaction. The study reveals a significant gap in the literature of perinatal MI.

Brief Emotion Focused Family Therapy: An Intervention for Parents of Children and Adolescents with Mental Health Issues

This study evaluated the 2-day intensive modality of Emotion Focused Family Therapy (EFFT). The intervention attempts to prepare parents to take a primary role in their child's recovery from a range of mental health issues. One hundred and twenty-four parents completed the intervention and provided data a week prior to intervention, post-intervention and at 4-month follow-up. Results include significantly reduced parent blocks and increased parental self-efficacy in relation to involvement in their child's recovery, as well as significant improvement in child symptomatology. The findings confirm positive results from an earlier pilot study involving eating disorders and demonstrate the potential for EFFT as an intervention for a range of clinical problems in children and youth.

Cognitive emotional processing across mood disorders

While impairments in cognitive emotional processing are key to the experience of mood disorders, little is understood of their shared and distinct features across major depressive disorder (MDD) and bipolar disorder (BD). In this review, we discuss the similarities and differences in abnormal emotional processing associated with mood disorders across the cognitive domains of perception, attention, memory, and reward processing, with a particular focus on how these impairments relate to the clinical profile of the disorders. We consider behavioral and neuroimaging evidence, especially that of the growing consensus surrounding mood-congruent biases in cognition, in combination with state- and trait-related characteristics in an attempt to provide a more comprehensive and translational overview of mood disorders. Special consideration is given to the shared phenomenon of mood instability and its role as a potential transdiagnostic marker across the prodrome and maintenance of mood disorders.

Affective instability in those with and without mental disorders: A case control study

BACKGROUND

Affective instability (AI) is transdiagnostic, and associated with suicidality and healthcare use. It has rarely been compared between diagnoses or to controls. We investigated: whether AI differs between clinical cases and controls and between diagnoses; how different AI components are correlated; and whether AI is associated with functioning in clinical cases.

METHODS

Cases (N = 69) from psychiatric services had a diagnosis of borderline personality disorder, bipolar disorder, major depression or psychosis and were compared to primary care controls (N = 25). Participants completed the affective lability scale (ALS), affective intensity measure (AIM), affective control scale (ACS), scored mood fluctuation rate and the WHO-DAS.

RESULTS

There was a significant difference in affective lability between cases and controls and across diagnostic groups (p < 0.001). Compared to controls, cases showed lower affective control (p < 0.05). There were no differences in affective intensity between cases and controls or between diagnostic groups, or in mood fluctuation rate between groups. ALS score (p < 0.001), and total number of medications (p < 0.046), were associated with functioning, independent of diagnosis.

LIMITATIONS

The sample size was modest. Cases were not in an acute illness episode and this could bias estimates of group difference towards the null.

CONCLUSION

Individuals with mental disorder demonstrate higher levels of affective lability and lower affect control than those without mental disorder. In contrast affective intensity may not be useful in demarcating abnormal affective experience. Independent of diagnosis, affective instability, as measured by affect lability, adversely impacts day-to-day functioning. It could be an important target for clinical intervention.

Borderline personality disorder: does its clinical features show specificity to differing developmental risk factors?

OBJECTIVES

To determine if differing developmental factors show specificity to differing manifestations of borderline personality disorder (BPD).

METHODS

A clinical sample of 73 females diagnosed with BPD undertook a psychiatrist interview and completed self-report questionnaires, including the semi-structured Diagnostic Interview for DSM-IV Personality Disorders (DIPD-IV) assessing for BPD status. A set of negative and potentially traumatic developmental factors were included in the assessment.

RESULTS

Childhood sexual abuse, affirmed by 49% of the sample, showed specificity in being linked with DIPD-defined affective instability. DIPD-defined identity disturbance also showed specificity in being associated only with reporting significant non-sexual developmental trauma. DIPD-defined anger and paranoia/dissociation showed minimal specificity and were associated with most antecedent developmental factors in adulthood.

CONCLUSIONS

Differing manifestations of BPD are likely to be shaped by specific and non-specific developmental events. Clarification of such links has the potential to shape more specific therapeutic interventions.

The Emerging Neurobiology of Bipolar Disorder

Bipolar disorder (BD) is a leading cause of global disability. Its biological basis is unknown, and its treatment unsatisfactory. Here, we review two recent areas of progress. First, the discovery of risk genes and their implications, with a focus on voltage-gated calcium channels as part of the disease process and as a drug target. Second, facilitated by new technologies, it is increasingly apparent that the bipolar phenotype is more complex and nuanced than simply one of recurring manic and depressive episodes. One such feature is persistent mood instability, and efforts are underway to understand its mechanisms and its therapeutic potential. BD illustrates how psychiatry is being transformed by contemporary neuroscience, genomics, and digital approaches.

Oral contraceptives positively affect mood in healthy PMS-free women: A longitudinal study

OBJECTIVE

Menstrual cycle phase and oral contraceptives (OC) use influence mood and cognition and these effects may be moderated by the mineralocorticoid receptor (MR) genotype. The effect of menstrual cycle phase on mood may be increased if participants know that this is the focus of study. We assessed aspects associated with reproductive depression such as mood, interpersonal sensitivity, affect lability and depressive cognitions in MR-genotyped OC-users and naturally cycling (NC) women in a carefully masked design.

METHODS

A homogenous sample of healthy, PMS-free, pre-menopausal MR-genotyped women (n=92) completed online questionnaires eight times during two consecutive cycles.

RESULTS

The masking of the research question was successful. OC-users did not differ significantly from NC women in positive and negative affect at the time of assessment, personality characteristics (e.g. neuroticism) or mental and physical health. Both groups reported more shifts in anger in the first cycle week (p<0.001; η_p²=0.08). Compared to NC women, OC-users reported fewer mood-shifts between depression and elation in the mid-luteal phase of the menstrual cycle (p=0.002; η_p²=0.10) and had fewer ruminating thoughts at all phases (p=0.003; η_p²=0.11). Effects of MR-genotype were not significant after correction for multiple comparisons.

CONCLUSION

OC users scored more favorably on measures associated with reproductive depression. OC users also showed a decreased affect variability possibly indicating an emotional blunting effect, which is in line with previous reports on affect-stabilizing effects of OC. Limitations were loss of cases due to irregularities in the menstrual cycle length and possible confounding by the 'survivor effect', since almost all OC-users took OC for more than a year.

Genome-wide analysis in UK Biobank identifies four loci associated with mood instability and genetic correlation with major depressive disorder, anxiety disorder and schizophrenia

Mood instability is a core clinical feature of affective and psychotic disorders. In keeping with the Research Domain Criteria approach, it may be a useful construct for identifying biology that cuts across psychiatric categories. We aimed to investigate the biological validity of a simple measure of mood instability and evaluate its genetic relationship with several psychiatric disorders, including major depressive disorder (MDD), bipolar disorder (BD), schizophrenia, attention deficit hyperactivity disorder (ADHD), anxiety disorder and post-traumatic stress disorder (PTSD). We conducted a genome-wide association study (GWAS) of mood instability in 53,525 cases and 60,443 controls from UK Biobank, identifying four independently associated loci (on chromosomes 8, 9, 14 and 18), and a common single-nucleotide polymorphism (SNP)-based heritability estimate of ~8%. We found a strong genetic correlation between mood instability and MDD (r g = 0.60, SE = 0.07, p = 8.95 × 10-17) and a small but significant genetic correlation with both schizophrenia (r g = 0.11, SE = 0.04, p = 0.01) and anxiety disorders (r g = 0.28, SE = 0.14, p = 0.04), although no genetic correlation with BD, ADHD or PTSD was observed. Several genes at the associated loci may have a role in mood instability, including the DCC netrin 1 receptor (DCC) gene, eukaryotic translation initiation factor 2B subunit beta (eIF2B2), placental growth factor (PGF) and protein tyrosine phosphatase, receptor type D (PTPRD). Strengths of this study include the very large sample size, but our measure of mood instability may be limited by the use of a single question. Overall, this work suggests a polygenic basis for mood instability. This simple measure can be obtained in very large samples; our findings suggest that doing so may offer the opportunity to illuminate the fundamental biology of mood regulation.

Pharmacotherapy of emotional dysregulation in adults with ADHD: A systematic review and meta-analysis

Emotional dysregulation (ED) is a dysfunction in modifying an emotional state in an adaptive and goal oriented way, with excitability, ease anger, and mood lability. It is present in up to 70% of adults with ADHD, regardless of other comorbidities, and substantially worsens the psychosocial outcomes of the disorder. Besides fronto-parietal circuits mediating top-down control, brain regions involved in bottom-up processes (e.g., amygdala, orbitofrontal cortex, and ventral striatum) are implicated in ED. We performed a systematic review/meta-analysis of double-blind randomized controlled trials of ADHD medications to assess their effects on ED in adults with ADHD. We searched an extensive set of databases, international trials registries, and contacted study authors/drug companies for unpublished data. We retained 21 trials. We found small-to-moderate effects (methylphenidate: SMD=0.34, 95% CI=0.23-0.45; atomoxetine: SMD=0.24, 95% CI=0.15-0.34; lisdexamfetamine: SMD=0.50, 95% CI=0.21-0.8). We suggest that, whilst ADHD medications are effective on ADHD core symptoms, they may be less effective on bottom-up mechanisms underlying ED. Further research on novel pharmacological and non-pharmacological strategies for ED in adults with ADHD is warranted.

PROSPERO

CRD42017068426.

Emotional reactivity, functioning, and C-reactive protein alterations in remitted bipolar patients: Clinical relevance of a dimensional approach

OBJECTIVES

Inter-episode mood instability has increasingly been considered in bipolar disorder. This study aimed to investigate emotional reactivity as a major dimension for better characterizing remitted bipolar patients with subthreshold mood symptoms and functional status. This study also aimed to investigate whether high-sensitivity C-reactive protein, a marker of low-grade inflammation, could be a biological marker of emotional dysregulation in bipolar disorder (BD).

METHODS

Cross-sectional study of 613 subjects who met Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition criteria for BD recruited from the FondaMental Advanced Centers of Expertise in Bipolar Disorders cohort from 2009 to 2014. All patients had been in remission for at least 3 months before assessment. Patients were classified into three groups according to levels of emotional reactivity. Emotional reactivity was assessed by using the Multidimensional Assessment of Thymic States, and functional status was assessed by the Functioning Assessment Short Test. Clinical characteristics and blood sample were collected from all patients.

RESULTS

In total, 415 (68%) patients had abnormal emotional reactivity. Independent of potential confounders, including age, gender and subthreshold mood symptoms, serum levels of high-sensitivity C-reactive protein were significantly higher in patients with emotional hyper-reactivity (median = 4.0 mg/L, interquartile range = 2.7-5.6), and with emotional hypo-reactivity (median = 3.0 mg/L, interquartile range = 1-4) compared with patients with normal emotional reactivity (median = 0.95 mg/L, interquartile range = 0.4-1.9, p < 0.001). Patients with emotional hyper-reactivity showed significant cognitive functioning impairment ( p < 0.001).

CONCLUSIONS

Emotional reactivity appears to be a relevant dimension for better characterizing remitted bipolar patients with subthreshold mood symptoms. Levels of high-sensitivity C-reactive protein may be an objective marker of emotional dysregulation in BD. Further studies are needed to confirm our findings.

Innovative approaches to bipolar disorder and its treatment

All psychiatric disorders have suffered from a dearth of truly novel pharmacological interventions. In bipolar disorder, lithium remains a mainstay of treatment, six decades since its effects were serendipitously discovered. The lack of progress reflects several factors, including ignorance of the disorder's pathophysiology and the complexities of the clinical phenotype. After reviewing the current status, we discuss some ways forward. First, we highlight the need for a richer characterization of the clinical profile, facilitated by novel devices and new forms of data capture and analysis; such data are already promoting a reevaluation of the phenotype, with an emphasis on mood instability rather than on discrete clinical episodes. Second, experimental medicine can provide early indications of target engagement and therapeutic response, reducing the time, cost, and risk involved in evaluating potential mood stabilizers. Third, genomic data can inform target identification and validation, such as the increasing evidence for involvement of calcium channel genes in bipolar disorder. Finally, new methods and models relevant to bipolar disorder, including stem cells and genetically modified mice, are being used to study key pathways and drug effects. A combination of these approaches has real potential to break the impasse and deliver genuinely new treatments.

Study of prodromal and residual symptoms of depression

BACKGROUND

The definitive diagnosis of depression calls for fulfillment of certain criteria in terms of symptoms, severity, and duration, but subthreshold cases are not uncommon. These may evolve to become clinically diagnosable depression preceded by prodrome. The current study was conducted to study prodromal and residual symptoms in depression.

MATERIALS AND METHODS

Eighty follow-up patients of depressive episode (F32, International Classification of Diseases-10) in remission defined by Hamilton Depression Rating Scale score <8 were interviewed. A symptom was identified as prodromal if it appeared at any time before the period of onset of symptoms sufficient to fulfill the criteria to make a diagnosis of depressive episode. Clinical Interview for Depression and Related Syndromes was used to identify the presence of symptoms. Statistical analysis was done with McNemar test and Pearson's Chi-square test using SPSS software version 20.0.

RESULTS

The mean age of patients was 41.25 (±8.58) years and the sample was predominately female patients (80%). All the eighty patients had at least one prodromal symptom. The mean duration of prodrome was 115 (±64.46) days. Irritability (45%), insomnia (45%), and reduced energy (43.8%) were the most frequent prodromal symptoms. Frequency of irritability was comparable in prodromal and residual phases of depression (P = 0.074) and significantly associated with a positive family history of depression (P = 0.004).

CONCLUSION

Prodrome is present in most cases of depression lasting from weeks to months. Prodrome is frequented by irritability, anxiety, sleep problems, and fatigability. Irritability is associated with genetic loading of depression and likely to present as residual symptom if it is present in prodromal phase.

Differentiating the everyday emotion dynamics of borderline personality disorder from major depressive disorder and bipolar disorder

A major barrier to the understanding of emotion dynamics in borderline personality disorder (BPD) lies in its substantial comorbidity with major depressive disorder (MDD) and bipolar disorder (BD). Whereas BPD has often been characterized in terms of dynamic emotional processes, including instability, reactivity, and inertia, its substantial comorbidity with MDD and BD makes it difficult to discern the specificity of these dynamics. To differentiate the emotion dynamics of BPD from those of MDD and BD, an experience sampling study of 38 participants with BPD, 15 participants with MDD, 14 participants with BD, and 62 healthy controls obtained reports of interpersonal challenges and emotions 5 times daily for 2 weeks. Interpersonal challenges included rejection, betrayal, abandonment, offense, disappointment, and self-image challenge; emotions included anger, excitement, guilt, happiness, irritability, and shame. Multilevel analyses revealed that heightened interpersonal reactivity of guilt and shame and heightened inertia of shame were relatively specific to BPD. These findings could not be accounted for by the presence of current MDD or BD. By contrast, heightened instability of anger and irritability and heightened inertia of irritability appeared to be largely transdiagnostic. Implications for clinical assessment, research, and theory are discussed. (PsycINFO Database Record

Depression and Schizophrenia: Cause, Consequence, or Trans-diagnostic Issue?

The presence of depression in schizophrenia has been a challenge to the Kraepelinian dichotomy, with various attempts to save the fundamental distinction including evoking and refining diagnoses such as schizoaffective disorder. But the tectonic plates are shifting. Here we put forward a summary of recent evidence regarding the prevalence, importance, possible aetiological pathways and treatment challenges that recognizing depression in schizophrenia bring. Taken together we propose that depression is more than comorbidity and that increased effective therapeutic attention to mood symptoms will be needed to improve outcomes and to support prevention.

Convergent individual differences in visual cortices, but not the amygdala across standard amygdalar fMRI probe tasks

The amygdala (AMG) has been repeatedly implicated in the processing of threatening and negatively valenced stimuli and multiple fMRI paradigms have reported personality, genetic, and psychopathological associations with individual differences in AMG activation in these paradigms. Yet the interchangeability of activations in these probes has not been established, thus it remains unclear if we can interpret AMG responses on specific tasks as general markers of its reactivity. In this study we aimed to assess if different tasks that have been widely used within the Affective Neuroscience literature consistently recruit the AMG.

METHOD

Thirty-two young healthy subjects completed four fMRI tasks that have all been previously shown to probe the AMG during processing of threatening stimuli: the Threat Face Matching (TFM), the Cued Aversive Picture (CAP), the Aversive and Erotica Pictures (AEP) and the Screaming Lady paradigm (SLp) tasks. Contrasts testing response to aversive stimuli relative to baseline or neutral stimuli were generated and correlations between activations in the AMG were calculated across tasks were performed for ROIs of the AMG.

RESULTS

The TFM, CAP and AEP, but not the SLp, successfully recruit the AMG, among other brain regions, especially when contrasts were against baseline or nonsocial stimuli. Conjunction analysis across contrasts showed that visual cortices (VisCtx) were also consistently recruited. Correlation analysis between the extracted data for right and left AMG did not yield significant associations across tasks. By contrast, the extracted signal in VisCtx showed significant associations across tasks (range r=0.511-r=0.630).

CONCLUSIONS

Three of the four paradigms revealed significant AMG reactivity, but individual differences in the magnitudes of AMG reactivity were not correlated across paradigms. By contrast, VisCtx activation appears to be a better candidate than the AMG as a measure of individual differences with convergent validity across negative emotion processing paradigms.

Affective lability and difficulties with regulation are differentially associated with amygdala and prefrontal response in women with Borderline Personality Disorder

The present neuroimaging study investigated two aspects of difficulties with emotion associated with Borderline Personality Disorder (BPD): affective lability and difficulty regulating emotion. While these two characteristics have been previously linked to BPD symptomology, it remains unknown whether individual differences in affective lability and emotion regulation difficulties are subserved by distinct neural substrates within a BPD sample. To address this issue, sixty women diagnosed with BPD were scanned while completing a task that assessed baseline emotional reactivity as well as top-down emotion regulation. More affective instability, as measured by the Affective Lability Scale (ALS), positively correlated with greater amygdala responses on trials assessing emotional reactivity. Greater difficulties with regulating emotion, as measured by the Difficulties with Emotion Regulation Scale (DERS), was negatively correlated with left Inferior Frontal Gyrus (IFG) recruitment on trials assessing regulatory ability. These findings suggest that, within a sample of individuals with BPD, greater bottom-up amygdala activity is associated with heightened affective lability. By contrast, difficulties with emotion regulation are related to reduced IFG recruitment during emotion regulation. These results point to distinct neural mechanisms for different aspects of BPD symptomology.

Similarities between emotional dysregulation in adults suffering from ADHD and bipolar patients

BACKGROUND

Emotional dysregulation in subjects with attention deficit and hyperactivity disorder (ADHD) is a topic of growing interest among clinicians and researchers. The present study aims at investigating components of emotional dysregulation in adults ADHD compared to subjects suffering from bipolar disorder (BD).

METHODS

A total of 150 adults ADHD, 335 adults BD subjects and 48 controls were assessed using the Affective Lability Scale (ALS) and the Affect Intensity Measure (AIM), measuring respectively emotion lability and emotion responsiveness.

RESULTS

ADHD and BD subjects scored significantly higher on the ALS compared to controls (p=0.0001). BD subjects scored above ADHD ones (3.07 (SD=0.66) vs. 2.30 (SD=0.68); p<0.0001). The average total scores achieved on the AIM were significantly different for the three groups (p=0.0001) with significantly higher scores for ADHD subjects compared to BD ones (3.74 (SD=0.59) vs. 3.56 (SD=0.69); p<0.0001).

LIMITATIONS

Suspected cases of ADHD in the BD and control groups were derived from the Wender Utah Rating Scale (WURS). This study is a retrospective one.

CONCLUSION

Our study thus highlights the importance of emotional dysregulation in adults suffering from ADHD, showing that they display higher emotional intensity than bipolar disorder subjects and controls. Although the current diagnostic criteria of ADHD do not contain an emotional dimension, a better recognition of the significance of emotional responsiveness in ADHD patients can improve the care afforded to these patients, beyond the inattentive and hyperactive/impulsive components.

The temporal course and clinical correlates of subjective impulsivity in bipolar disorder as revealed through ecological momentary assessment

BACKGROUND

Impulsivity is frequently linked with bipolar disorder and is associated with mania and negative outcomes. The temporal dynamics of subjective impulsivity are unclear, in particular whether impulsivity precedes or follows changes in positive or negative affect.

METHODS

A total of 41 outpatients with bipolar disorder (I or II) were provided with mobile devices for 11 weeks and completed twice-daily surveys about affective states and subjective impulsivity. We examined the association between aggregate subjective impulsivity with baseline global cognitive function, suicide risk ratings, and medication adherence, as well as concurrent and lagged associations with momentary positive and negative affect ratings.

RESULTS

A total of 2902 ratings were available across study subjects. Higher aggregate mean ratings of impulsivity were associated with worse baseline global cognitive function, prior suicide attempts, and self-reported problems with medication adherence, as well as more severe manic (but not depressive) symptoms. Time-lagged models indicated that greater negative affect, but not positive affect, predicted subsequent increases in subjective impulsivity, which, in turn, predicted diminished positive affect.

LIMITATIONS

Other measures of impulsivity with which to validate subjective ratings were unavailable and the sample was restricted to generally clinically stable outpatients.

CONCLUSIONS

Subjective impulsivity as measured by daily monitoring was associated with worse cognitive function and self-rated medication adherence, and higher suicide risk ratings. Impulsivity may be a maladaptive strategy to regulate negative affect in bipolar disorder.

Affective instability, childhood trauma and major affective disorders

BACKGROUND

Affective instability (AI), childhood trauma, and mental illness are linked, but evidence in affective disorders is limited, despite both AI and childhood trauma being associated with poorer outcomes. Aims were to compare AI levels in bipolar disorder I (BPI) and II (BPII), and major depressive disorder recurrent (MDDR), and to examine the association of AI and childhood trauma within each diagnostic group.

METHODS

AI, measured using the Affective Lability Scale (ALS), was compared between people with DSM-IV BPI (n=923), BPII (n=363) and MDDR (n=207) accounting for confounders and current mood. Regression modelling was used to examine the association between AI and childhood traumas in each diagnostic group.

RESULTS

ALS scores in descending order were BPII, BPI, MDDR, and differences between groups were significant (p<0.05). Within the BPI group any childhood abuse (p=0.021), childhood physical abuse (p=0.003) and the death of a close friend in childhood (p=0.002) were significantly associated with higher ALS score but no association was found between childhood trauma and AI in BPII and MDDR.

LIMITATIONS

The ALS is a self-report scale and is subject to retrospective recall bias.

CONCLUSIONS

AI is an important dimension in bipolar disorder independent of current mood state. There is a strong link between childhood traumatic events and AI levels in BPI and this may be one way in which exposure and disorder are linked. Clinical interventions targeting AI in people who have suffered significant childhood trauma could potentially change the clinical course of bipolar disorder.

Mood Instability and Irritability as Core Symptoms of Major Depression: An Exploration Using Rasch Analysis

BACKGROUND

Mood instability (MI) and irritability are related to depression but are not considered core symptoms. Instruments typically code clusters of symptoms that are used to define syndromic depression, but the place of MI and irritability has been under-investigated. Whether they are core symptoms can be examined using Rasch analysis.

METHOD

We used the UK Psychiatric Morbidity Survey 2000 data (n = 8,338) to determine whether the nine ICD/DSM symptoms, plus MI and irritability, constitute a valid depression scale. Rasch analysis was used, a method concerned with ensuring that items constitute a robust scale and tests whether the count of symptoms reflects an underlying interval-level measure. Two random samples of 500 were drawn, serving as calibration and validation samples. As part of the analysis, we examined whether the candidate symptoms were unidimensional, followed a Guttman pattern, were locally independent, invariant with respect to age and sex, and reliably distinguished different levels of depression severity.

RESULTS

A subset of five symptoms (sad, no interest, sleep, cognition, suicidal ideas) together with mood instability and irritability satisfactorily fits the Rasch model. However, these seven symptoms do not separate clinically depressed persons from the rest of the population with adequate reliability (Cronbach α = 0.58; Person Separation Index = 0.35), but could serve as a basis for scale development. Likewise, the original nine DSM depression symptoms failed to achieve satisfactory reliability (Cronbach α = 0.67; Person Separation Index = 0.51).

LIMITATIONS

The time frame over which symptoms were experienced varied, and some required recall over the last year. Symptoms other than those examined here might also be core depression symptoms.

CONCLUSION

Mood instability and irritability are candidate core symptoms of the depressive syndrome and should be part of its clinical assessment.

Mood instability: significance, definition and measurement

Mood instability is common, and an important feature of several psychiatric disorders. We discuss the definition and measurement of mood instability, and review its prevalence, characteristics, neurobiological correlates and clinical implications. We suggest that mood instability has underappreciated transdiagnostic potential as an investigational and therapeutic target.

Mood instability as a precursor to depressive illness: A prospective and mediational analysis

OBJECTIVE

Mood instability levels are high in depression, but temporal precedence and potential mechanisms are unknown. Hypotheses tested were as follows: (1) mood instability is associated with depression cross-sectionally, (2) mood instability predicts new onset and maintenance of depression prospectively and (3) the mood instability and depression link are mediated by sleep problems, alcohol abuse and life events.

METHOD

Data from the National Psychiatric Morbidity Survey 2000 at baseline (N = 8580) and 18-month follow-up (N = 2413) were used. Regression modeling controlling for socio-demographic factors, anxiety and hypomanic mood was conducted. Multiple mediational analyses were used to test our conceptual path model.

RESULTS

Mood instability was associated with depression cross-sectionally (odds ratio: 5.28; 95% confidence interval: [3.67, 7.59]; p < 0.001) and predicted depression inception (odds ratio: 2.43; 95% confidence interval: [1.03-5.76]; p = 0.042) after controlling for important confounders. Mood instability did not predict maintenance of depression. Sleep difficulties and severe problems with close friends and family significantly mediated the link between mood instability and new onset depression (23.05% and 6.19% of the link, respectively). Alcohol abuse and divorce were not important mediators in the model.

CONCLUSION

Mood instability is a precursor of a depressive episode, predicting its onset. Difficulties in sleep are a significant part of the pathway. Interventions targeting mood instability and sleep problems have the potential to reduce the risk of depression.