Impulsivity across the course of bipolar disorder

Inhibitory control in Bipolar Disorder disclosed by theta band modulation

BACKGROUND

Cognitive inhibition is key to cognitive control in healthy and psychiatric conditions. Bipolar Disorder (BD) individuals display a range of inhibitory deficits and high levels of impulsivity across all stages of the disease, including euthymia.

METHODS

We tested how the inhibition of heuristics in favor of analytical strategies influences the elaboration of sentences with logical quantifiers by means of a sentence-picture matching task in which the processing of quantified sentences containing the logical universal and particular quantifiers was required. Behavioral and brain oscillatory responses were assessed employing EEG recordings.

RESULTS

In Experiment 1, in a group of healthy volunteers, we demonstrated how the presence of a universal quantifier generates an inhibition, characterized by a high cognitive load, which is resolved at the expense of a poorer behavioral performance compared to a lower cognitive load and neutral control task. In Experiment 2, comparing healthy adults and BD patients, EEG time-frequency analysis showed a different modulation of the theta frequency band localized centrally in the medial frontal areas and representative of the different degrees of cognitive control between groups.

LIMITATIONS

Electrophysiological description should be interpreted with caution in light of the high signal-to-noise ratio determined by the complexity of the task.

CONCLUSIONS

Even in euthymia, BD limited availability of resources for cognitive inhibition impacts the functionality of a fronto-parietal cortical network, responsible for cognitive control, and orchestrated by the activity of frontal areas synchronized in theta and beta frequency.

Error monitoring and response inhibition in adolescents with bipolar disorders: An ERP study

Cognitive control develops throughout adolescence, a high-risk period for bipolar disorders (BD) onset. Despite neurobehavioral abnormalities in adults with BD, there is minimal research investigating deviations in cognitive control in adolescents with BD. Cognitive control involves numerous processes. Identifying the specific neural abnormalities in adolescent BD could provide precise targets for novel interventions that improve illness outcomes. The present study administered a Go/No-Go (GNG) task to 98 adolescents (44 BD; 54 controls) to activate response inhibition and error processes and recorded EEG for event-related potentials (ERPs) analysis. Stimulus-locked N2 and P3 (response inhibition) and response-locked error-related negativity (ERN; early error detection) and error positivity (Pe; conscious error detection) were analyzed. Adolescents with BD had attenuated Pe mean amplitudes following failed inhibition trials. There were no group differences in other ERP amplitudes, including N2, P3, and ERN. The pattern of findings implicates conscious error detection impairment in adolescents with BD, without support for deficits in more automatic, earlier error detection. Impaired conscious error detection in adolescents with BD may be an early expression of BD pathophysiology and a possible intervention target for cognitive rehabilitation. Further studies are needed to examine Pe in BD across the lifetime.

The clinical significance of emotional urgency in bipolar disorder: a scoping review

BACKGROUND

Emotional urgency, defined as a trait concept of emotion-based impulsivity, is at least moderately associated with general psychopathology. However, its clinical significance and associations with clinically relevant features of bipolar disorder remain unclear. This scoping review aims address this gap by determining the extent of evidence in this niche scope of study.

METHODS

Evidence of between-group differences of positive and negative urgency, its associations with mood severity, and all peripheral associations related to illness and psychosocial outcomes were synthesized based on PRISMA checklists and guidelines for scoping reviews (PRISMA-ScR).

DESIGN

Electronic databases were searched for articles published between January 2001 and January 2024. A total of 1013 entries were gathered, and a total of 10 articles were included in the final selection after the removal of duplicates and ineligible articles.

RESULTS

Differences in urgency scores between bipolar disorder and healthy controls were large (Cohen's d ranged from 1.77 to 2.20). Negative urgency was at least moderately associated with overall trauma, emotional abuse, neglect, suicide ideation, neuroticism, and irritable/cyclothymic temperament, whereas positive urgency was at least moderately associated with various aspects of aggression and quality of life. Positive but not negative urgency was associated with quality of life in bipolar disorder.

CONCLUSION

Large between-group differences found for emotional urgency in bipolar disorder imply large clinical significance. Emotional urgency was associated with worse clinical features and outcomes. Given the high clinical heterogeneity of the disorder, emotional urgency may be an important phenotype indicative of greater disorder severity.

Anhedonia and Delay Discounting: Differing Patterns of Brain-Behavior Relationships in Healthy Control Participants Versus Individuals With Posttraumatic Stress Disorder

BACKGROUND

Anhedonia may contribute to individual differences in delay discounting (DD). In prior work, we found that higher anhedonia was associated with shallower DD in healthy control (HC) participants but steeper DD in individuals with posttraumatic stress disorder (PTSD). In this study, we aimed to directly compare the relationship between anhedonia and DD across groups and to identify functional brain correlates of this interaction.

METHODS

Participants (HC group: n = 23, DSM-5 PTSD group: n = 23) completed a questionnaire assessing anhedonia (Snaith-Hamilton Pleasure Scale [SHAPS]), task-based functional magnetic resonance imaging of decision making including DD, and resting-state functional magnetic resonance imaging. Task-based activity and resting-state functional connectivity were evaluated in reward-related regions that have also been implicated in PTSD (nucleus accumbens [NAcc], right anterior insula).

RESULTS

Higher SHAPS scores were associated with steeper DD in PTSD, but there was no relationship between DD and SHAPS in the HC group. There was a significant group-by-SHAPS interaction for NAcc activity, t31 = 2.92, p = .007: Greater NAcc activity when immediate rewards were chosen was associated with higher SHAPS in the PTSD group but lower SHAPS in the HC group. In resting-state functional connectivity, there was a group-by-SHAPS interaction between the NAcc seed and right parietal and frontal pole clusters.

CONCLUSIONS

These results extend prior findings that anhedonia is associated with steeper DD in PTSD and demonstrate that this behavioral finding occurs in the context of NAcc hyperactivity to immediate rewards and hyperconnectivity in anhedonic individuals with PTSD.

Neuroanatomical and functional substrates of the hypomanic personality trait and its prediction on aggression

Hypomanic personality manifests a close link with several psychiatric disorders and its abnormality is a risk indicator for developing bipolar disorders. We systematically investigated the potential neuroanatomical and functional substrates underlying hypomanic personality trait (HPT) and its sub-dimensions (i.e., Social Vitality, Mood Volatility, and Excitement) combined with structural and functional imaging data as well as their corresponding brain networks in a large non-clinical sample across two studies (n = 464). Behaviorally, HPT, specifically Mood Volatility and Excitement, was positively associated with aggressive behaviors in both studies. Structurally, sex-specific morphological characteristics were further observed in the motor and top-down control networks especially for Mood Volatility, although HPT was generally positively associated with grey matter volumes (GMVs) in the prefrontal, temporal, visual, and limbic systems. Functionally, brain activations related to immediate or delayed losses were found to predict individual variability in HPT, specifically Social Vitality and Excitement, on the motor and prefrontal-parietal cortices. Topologically, connectome-based prediction model analysis further revealed the predictive role of individual-level morphological and resting-state functional connectivity on HPT and its sub-dimensions, although it did not reveal any links with general brain topological properties. GMVs in the temporal, limbic (e.g., amygdala), and visual cortices mediated the effects of HPT on behavioral aggression. These findings suggest that the imbalance between motor and control circuits may be critical for HPT and provide novel insights into the neuroanatomical, functional, and topological mechanisms underlying the specific temperament and its impacts on aggression.

Clinical assessment of impulsiveness and defence mechanisms in young patients with mood disorders in a two-year prospective study

AIM

There have been limited prospective investigations of early clinical markers involved in mood regulation and diagnosis change in young patients. This study aimed to evaluate the changes in impulsivity and defence mechanisms in patients with major depressive disorder (MDD) and bipolar disorder (BD) with acute symptoms and remission compared to healthy controls (HC), and possible psychological predictors of diagnosis conversion.

METHODS

Seventy-nine young MDD or BD patients and 40 HC were enrolled in a two-year prospective study. A comprehensive clinical interview focused on clinical and psychological evaluation during follow-up visits. The severity of depressive symptoms was evaluated using the Hamilton Depression Rating Scale (HDRS-17), whilst the Young Mania Rating Scale (YMRS) was used for hypo/manic symptoms during each control visit. All patients completed the Defence Style Questionnaire (DSQ-40) and Barratt Impulsiveness Scale (BIS-11).

RESULTS

Patients used more immature defences, and had significantly higher total impulsivity scores than controls. BD patients had elevated motor and non-planning impulsivity compared with HC and MDD subjects. Total and non-planning impulsiveness remained elevated in euthymia in BD and MDD compared to HC. There were no statistically significant differences in total defence styles and impulsiveness scores at baseline vs. euthymia in MDD or BD patients groups. Significantly higher dissociation scores at baseline discriminated depressive patients who convert to BD in their diagnosis.

CONCLUSIONS

Patients with acute mood symptoms used more frequent immature defences and had significantly higher total impulsivity scores than healthy persons. A lack of differences in total defence styles and impulsiveness between patients with acute symptoms and after reaching euthymia in both MDD and BD groups indicates that they are independent of disease status. Dissociation defence mechanisms may be an early diagnostic indicator of BD.

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.

Neural correlates of impulsivity in bipolar disorder: A systematic review and clinical implications

Impulsivity is a common feature of bipolar disorder (BD) with ramifications for functional impairment and premature mortality. This PRISMA-guided systematic review aims to integrate findings on the neurocircuitry associated with impulsivity in BD. We searched for functional neuroimaging studies that examined rapid-response impulsivity and choice impulsivity using the Go/No-Go Task, Stop-Signal Task, and Delay Discounting Task. Findings from 33 studies were synthesized with an emphasis on the effect of mood state of the sample and affective salience of the task. Results suggest trait-like brain activation abnormalities in regions implicated in impulsivity that persist across mood states. During rapid-response inhibition, BD exhibit under-activation of key frontal, insular, parietal, cingulate, and thalamic regions, but over-activation of these regions when the task involves emotional stimuli. Delay discounting tasks with functional neuroimaging in BD are lacking, but hyperactivity of orbitofrontal and striatal regions associated with reward hypersensitivity may be related to difficulty delaying gratification. We propose a working model of neurocircuitry dysfunction underlying behavioral impulsivity in BD. Clinical implications and future directions are discussed.

Dimensions of the Hamilton Depression Rating Scale Correlate with Impulsivity and Personality Traits among Youth Patients with Depression

The heterogeneity of symptoms in young patients with major depression disorder makes it difficult to properly identify and diagnose. Therefore, the appropriate evaluation of mood symptoms is important in early intervention. The aim of this study was to (a) establish dimensions of the Hamilton Depression Rating Scale (HDRS-17) in adolescents and young adults and (b) perform correlations between the identified dimensions and psychological variables (impulsivity, personality traits). This study enrolled 52 young patients with major depression disorder (MDD). The severity of the depressive symptoms was established using the HDRS-17. The factor structure of the scale was studied using the principal component analysis (PCA) with varimax rotation. The patients completed the self-reported Barratt Impulsiveness Scale (BIS-11) and Temperament and Character Inventory (TCI). The three dimensions of the HDRS-17 identified as core in adolescent and young patients with MDD were (1) psychic depression/motor retardation, (2) disturbed thinking, and (3) sleep disturbances/anxiety. In our study, dimension 1 correlated with reward dependence and cooperativeness; dimension 2 correlated with non-planning impulsivity, harm avoidance, and self-directedness; and dimension 3 correlated with reward dependence. Conclusions: Our study supports the previous findings, which indicate that a certain set of clinical features (including the HDRS-17 dimensions, not only total score) may represent a vulnerability pattern that characterizes patients with depression.

Clinical correlates of comorbid attention deficit hyperactivity disorder in adults suffering from bipolar disorder: A meta-analysis

OBJECTIVE

Attention deficit hyperactivity disorder is a frequent comorbid condition in adults with bipolar disorder. We performed a meta-analysis aimed at assessing sociodemographic and clinical correlates of attention deficit hyperactivity disorder in bipolar disorder.

METHOD

We searched main electronic databases up to June 2021. Random-effects meta-analyses, with relevant meta-regression and quality-based sensitivity analyses, were carried out to estimate the association between attention deficit hyperactivity disorder and putative correlates, grading the quality of evidence.

RESULTS

We included 43 studies, based on 38 independent samples. Attention deficit hyperactivity disorder participants were more likely to be males (odds ratio = 1.46; p < 0.001) and unemployed (odds ratio = 1.45; p = 0.045), and less likely to be married (odds ratio = 0.62; p = 0.014). They had an earlier onset of bipolar disorder (standardized mean difference = -0.36; p < 0.001); more mood episodes (standardized mean difference = 0.35; p = 0.007), particularly depressive (standardized mean difference = 0.30; p = 0.011) and mixed (standardized mean difference = 0.30; p = 0.031) ones; higher odds of using antidepressants (odds ratio = 1.80; p = 0.024) and attempted suicides (odds ratio = 1.83; p < 0.001) and lower odds of psychotic features (odds ratio = 0.63; p = 0.010). Moreover, they were more likely to have generalized anxiety disorder (odds ratio = 1.50; p = 0.019), panic disorder (odds ratio = 1.89; p < 0.001), social phobia (odds ratio = 1.61; p = 0.017), eating disorders (odds ratio = 1.91; p = 0.007), antisocial personality disorder (odds ratio = 3.59; p = 0.004) and substance (odds ratio = 2.29; p < 0.001) or alcohol (odds ratio = 2.28; p < 0.001) use disorders. Quality of the evidence was generally low or very low for the majority of correlates, except for bipolar disorder onset and alcohol/substance use disorders (high), and suicide attempts (moderate).

CONCLUSION

Comorbid bipolar disorder/attention deficit hyperactivity disorder may have some distinctive clinical features including an earlier onset of bipolar disorder and higher comorbid alcohol/substance use disorder rates. Further research is needed to identify additional clinical characteristics of this comorbidity.

The effect of social exclusion on intertemporal choice in suicide attempters: A preliminary experimental study

BACKGROUND

Suicide-related theories and a growing body of evidence suggest that suicidal patients may have a tendency toward "short-sightedness"-the preference for immediate gratification when making intertemporal choice-and that social exclusion may exacerbate this tendency in suicidal patients. The present study examined the intertemporal choice performance of suicide attempters under conditions of social exclusion in a sample of affective disorder patients.

METHODS

A total of 64 affective disorder patients (22 non-suicidal patients, 24 single-suicide attempters and 18 multiple-suicide attempters) completed an intertemporal choice task in an exclusion or a non-exclusion condition. Social exclusion was manipulated using the Cyberball paradigm.

RESULTS

Non-suicidal patients and single-suicide attempters both exhibited an exaggerated preference for immediate rewards in the exclusion condition compared with the non-exclusion condition; in contrast, the multiple-suicide attempters appeared relatively indifferent to the social exclusion, exhibiting virtually identical preferences for immediate rewards in both the exclusion and non-exclusion conditions. In addition, the multiple-suicide attempters exhibited an exaggerated preference for immediate rewards compared with non-suicidal patients and single-suicide attempters in the non-exclusion condition, while the three groups did not differ in the exclusion condition.

CONCLUSIONS

Affective disorder patients with a single or no suicide attempts are more short-sighted after being excluded, while those with multiple suicide attempts appeared consistent short-sightedness in both exclusion and non-exclusion conditions. The study provides preliminary evidence of the role of disadvantageous intertemporal choice in the suicidal process. Future research replicate and extend these findings could have implications for suicide prevention and intervention.

The interplay of daily affect and impulsivity measured by mobile surveys in bipolar disorder

Background

Impulsivity is a prominent feature of bipolar disorder associated with various negative sequelae; moreover, it may be a precursor to shifts in affect or mood, but little is known about its association with affect on a day-to-day timescale. Ecological momentary assessments (a method that captures moment-to-moment ratings of psychological states by repeatedly sampling the same individual) of impulsivity and affect using mobile surveys allow for more nuanced examination of mechanisms of mood and behavior dysregulation. However, few existing studies have validated an ecological momentary assessment of impulsivity in bipolar disorder and examined its time-lagged associations with positive and negative affect. 70 participants with bipolar disorder and 102 healthy comparisons participated in an intensive longitudinal study: they underwent 14 days of ecological momentary assessment data collection annually for 1–4 years. Multiple measures of impulsivity and affect were collected using self-report, behavioral, and ecological momentary assessment modalities; these measures were compared, and levels of impulsivity were compared between bipolar disorder and healthy comparison groups. Time-lagged analyses using daily means explored the next-day predictive relationship of impulsivity on positive/negative affect, and vice versa.

Results

The ecological momentary measure of impulsivity was moderately correlated with the self-report but not behavioral impulsivity measure. Bipolar disorder participants evinced higher self-report, behavioral, and daily impulsivity than healthy comparison participants. Time-lagged analyses revealed a bi-directional association between high impulsivity and high next-day negative (but not positive) affect. Post hoc analyses showed that impulsivity specifically predicted next-day anger and anxiety.

Conclusions

Our multimodal assessment of impulsivity allowed for an examination of the day-to-day course of impulsivity and affect, crucial steps toward understanding the mechanisms of mood symptom and episode onset in bipolar disorder.

Risk for bipolar spectrum disorders associated with positive urgency and orbitofrontal cortical grey matter volume

Bipolar spectrum disorders (BSDs) are associated with reward hypersensitivity, impulsivity, and structural abnormalities within the brain's reward system. Using a behavioral high-risk study design based on reward sensitivity, this paper had two primary objectives: 1) investigate whether elevated positive urgency, the tendency to act rashly when experiencing extreme positive affect, is a risk for or correlate of BSDs, and 2) examine the nature of the relationship between positive urgency and grey matter volume in fronto-striatal reward regions, among individuals at differential risk for BSD. Young adults (ages 18-28) screened to be moderately reward sensitive (MReward; N = 42), highly reward sensitive (HReward; N = 48), or highly reward sensitive with a lifetime BSD (HReward + BSD; N = 32) completed a structural MRI scan and the positive urgency subscale of the UPPS-P scale. Positive urgency scores varied with BSD risk (MReward < HReward < HReward + BSD; ps≤0.05), and positive urgency interacted with BSD risk group in predicting lateral OFC volume (p <.001). Specifically, the MReward group showed a negative relationship between positive urgency and lateral OFC volume. By contrast, there was no relationship between positive urgency and lateral OFC grey matter volume among the HReward and HReward + BSD groups. The results suggest that heightened trait positive urgency is a pre-existing vulnerability for BSD that worsens with illness onset, and there is a distinct relationship between positive urgency and lateral OFC volume among individuals at high versus low risk for BSD. These findings have implications for understanding the expression and development of impulsivity in BSDs.

Rethinking "aggression" and impulsivity in bipolar disorder: Risk, clinical and brain circuitry features

BACKGROUND

Elevated aggression and impulsivity are implicated in Bipolar Disorder (BD); however, relationships between these behavioral constructs have not been clarified, which can lead to misconceptions with negative consequences including stigma and adverse outcomes including suicide. The study aimed to clarify brain-based distinctions between the two constructs and their associations to risk factors, symptoms and suicide thoughts and behaviors.

METHODS

Self-rated Brown-Goodwin Aggression (BGA) and Barratt Impulsiveness Scale (BIS) scores were compared between adults with BD (n = 38, 74% female) and healthy controls (HC, n = 29, 64% female). Relationships were examined between BGA and BIS with childhood trauma questionnaire (CTQ), mood, comorbidities, and magnetic resonance imaging gray matter volume (GMV) assessments.

RESULTS

In BD, BGA and BIS total scores were both elevated and associated with childhood maltreatment (CM), particularly emotional CM, depression, substance use disorders (SUDs) and suicide attempts (SAs). BGA scores were increased by items corresponding to dysregulation of emotional and social behavior and associated with elevated mood states and suicide ideation and GMV decreases in bilateral orbitofrontal cortex and left posterior insula brain regions, previously associated with these behaviors and clinical features. BIS motor impulsiveness scores were associated with GMV decreases in anterior cingulate cortex implicated in mood and behavioral dyscontrol.

LIMITATIONS

modest sample size, self-reports CONCLUSIONS: The findings suggest separable brain-based domains of dysfunction in BD of motor impulsiveness versus emotionally dysregulated feelings that are primarily self-directed. Both domains are associated with suicide behavior and modifiable risk factors of CM, depression and SUDs that could be targeted for prevention.

Early life stress and substance use disorders: The critical role of adolescent substance use

Early life stress (ELS) is a well-established risk factor for many psychiatric and medical disorders, including substance use disorders (SUDs). The relationship between ELS and SUDs is complex and there are likely multiple pathways from ELS to adverse substance use outcomes. The association between ELS and substance use emerges in adolescence. Adolescence is a critical period in development during which substance exposure markedly increases risk for SUDs. Therefore, this review focuses on the literature supporting the hypothesis that ELS increases risk for the development of SUDs through its influence on adolescent substance use. We discuss studies substantiating the role of ELS in adolescent substance use and explore how internalizing and externalizing psychopathology may be antecedents of substance use in adolescence. We examine clinical work suggesting ELS sculpts the Hypothalamic-Pituitary-Adrenal (HPA) Axis and developing brain-particularly subcortical brain regions that underlie stress response, mesocorticolimbic brain systems associated with reward sensitivity, and prefrontal regions that underlie executive control-in a way that increases risk for adolescent substance use and SUDs. We further explore how substance use during adolescence alters structure and function of these same systems, and how brain changes following ELS and adolescent substance use may independently, additively, or interactively contribute to risk for addiction. We conclude by discussing how the current literature can inform interventions aimed at reducing risk for SUDs in individuals with a history of ELS.

Behavioral mediators of stress-related mood symptoms in adolescence & young adulthood

BACKGROUND

Stress is a risk factor for unipolar and bipolar mood disorders, but the mechanisms linking stress to specific symptoms remain elusive. Behavioral responses to stress, such as impulsivity and social withdrawal, may mediate the associations between stress and particular mood symptoms.

METHODS

This study evaluated behavioral mediators of the relationship between self-reported intensity of daily stress and mood symptoms over up to eight weeks of daily diary surveys. The sample included individuals with unipolar or bipolar disorders, or with no psychiatric history (n = 113, ages 15-25).

RESULTS

Results showed that higher daily stress was related to higher severity of mania, and this pathway was mediated by impulsive behaviors. Higher stress also predicted higher severity of anhedonic depression, and social withdrawal mediated this relationship. A k-means clustering analysis revealed six subgroups with divergent profiles of stress-behavior-symptom pathways.

LIMITATIONS

Given the observational study design, analyses cannot determine causal relationships amongst these variables. Further work is needed to determine how relationships between these variables may vary based on stressor type, at different timescales, and within different populations.

CONCLUSIONS

Findings support a theoretical model in which impulsivity and social withdrawal act as behavioral mediators of the relationship between stress and mood symptoms. Additionally, distinct patterns of reactivity distinguished subgroups of people vulnerable to particular types of mood symptoms. These results provide novel information about how stress-reactive behaviors relate to specific mood symptoms, which may have clinical relevance as targets of intervention.

Aberrant Temporal Variability in Brain Regions during Risk Decision Making in Patients with Bipolar I Disorder: A Dynamic Effective Connectivity Study

Bipolar I disorder (BD-I) is associated with high-risk behaviors, such as suicide attempts and addictive substance abuse. Understanding brain activity exposure to risk decision making provides evidence for the treatment of BD-I patients. This study aimed to investigate the temporal dynamics of brain connectivity underlying risk decision making in patients with BD-I. A total of 101 subjects (48 BD-I patients and 53 age- and gender-matched healthy controls (HCs)) were included in this research. We analyzed the fMRI data acquired during Balloon Analog Risk Task (BART) performance. Voxel-wise dynamic effective connectivity (dEC) was employed to measure the activities in 264 brain regions. The coefficient of variation (CV) was calculated as temporal dynamics of brain connectivity. Finally, we used structural equation modeling (SEM) to determine the relationships of dEC in brain regions with clinical symptoms, behavior performances in patients. Results showed that BD-I patients exhibited increased dynamics in four lobes and exhibited decreased in three frontal regions. Besides, SEM results showed that the impulsive symptoms of patients were affected by the dEC during both resting and task states. Moreover, the dEC of left supramarginal gyrus (SMG) influenced those of left orbital frontal and right cuneus (CUN), as well as the affective symptoms and BART behaviors in patients with BD-I. Our results suggested that the altered temporal dynamics of brain connectivity might contribute to the impulsivity of BD-I during resting and task states. More importantly, the left SMG might be a therapeutic target to reduce the risk behavior in BD-I patients.

Emotion regulation in pediatric bipolar disorder: A meta-analysis of published studies

BACKGROUND

Emotion regulation is a relatively recent topic in psychiatry, and has only recently begun to be tested across Pediatric Bipolar Disorder (PBD). To date, no meta-analysis has investigated the presence of emotion regulation deficits in PBD patients.

OBJECTIVES

The aim of this study is to understand where the literature stands on this topic, as well as how different researchers are measuring and grasping the concept of emotion regulation in pediatric bipolar disorders.

METHODS

A systematic search of trials using the terms ("Pediatric Bipolar Disorder") AND ("Emotion Regulation" OR "Affect Regulation" OR "Mood Lability" OR "Mood Instability" OR "Irritability") was conducted using PubMed, Google Scholar, ResearchGate, Web of Science and Psych Info databases. Of the initial 366 articles identified, 8 met eligibility criteria for the meta-analysis and were included in this study.

RESULTS

There is a statistically significant difference in Accuracy in Emotion Regulation tasks, with a tendency for lower accuracy in PBD patients; however, both groups did not differ statistically regarding Response Time.

CONCLUSION

Our data suggests that PBD patients do present emotion regulation deficits, particularly regarding facial emotion recognition and affective language interference tasks mediated by cognitive assignments. These results have important implications in developing novel psychotherapeutic interventions for this population.

Altered Risk-Taking Behavior in Early-Stage Bipolar Disorder With a History of Psychosis

Altered risk-taking propensity is an important determinant of functional impairment in bipolar disorder. However, prior studies primarily assessed patients with chronic illness, and risk-taking has not been evaluated in the early illness course. This study investigated risk-taking behavior in 39 euthymic early-stage bipolar disorder patients aged 16-40 years who were treated within 3 years from their first-episode mania with psychotic features and 36 demographically-matched healthy controls using the Balloon Analog Risk Task (BART), a well-validated risk-taking performance-based paradigm requiring participants to make responses for cumulative gain at increasing risk of loss. Relationships of risk-taking indices with symptoms, self-reported impulsivity, cognitive functions, and treatment characteristics were also assessed. Our results showed that patients exhibited significantly lower adjusted scores (i.e., average balloon pumps in unexploded trials) (p = 0.001), lower explosion rate (p = 0.007) and lower cumulative scores (p = 0.003) than controls on BART, indicating their suboptimal risk-taking performance with increased propensity for risk aversion. Risk-taking indices were not correlated with any symptom dimensions, self-reported impulsivity, cognitive functions or antipsychotic dose. No significant difference was observed between patients with and without antipsychotic medications on self-reported impulsivity or any of the BART performance indices. This is the first study to examine risk-taking behavior in early-stage bipolar disorder with history of psychosis and indicates that patients displayed altered risk-taking with increased risk aversion compared with controls. Further research is needed to clarify longitudinal trajectory of risk-taking propensity and its relationships with psychosis and functional outcome in the early stage of bipolar disorder.

Psychiatric and psychological features of children at high-risk for bipolar disorder

BACKGROUND

Psychological/psychiatric features of high risk children (HR) for bipolar disorder are majorly overlooked. We aimed to compare psychological profiles (eg. anger level/ management, attachment/stress-coping mechanisms and emotional regulation difficulties) of HR with healthy controls.

METHOD

Total of 60 children in HR and 55 children in control group were evaluated using Trait Anger Scale (TAS), Anger Expression Scale (AES), Inventory of Parent/Peer Attachment (IPPA), Coping Style Scale (CSS) and Difficulties in Emotion Regulation Scale (DERS).

RESULTS

AXE/In and AXE/Con subscales of AES, "trust" and "communication" facets of IPPA-Peer and "communication" facet of IPPA-Parent were significantly lower in HR. They scored higher in "helpless" and lower in "submissive" and "optimistic" subscales of CSS. HR scored higher only in "lack of emotional awareness" facet of DERS.

LIMITATIONS

Self-reported scales which we used, may be susceptible to subjective personal characteristics. Also cross-sectional design of our study may have captured only a fraction of rapidly changing developmental processes.

CONCLUSIONS

Lower AXE/In and AXE/Con scores of HR are similar to Type-A Behavior Pattern which is includes agressiveness and impulsiveness. Higher "helpless", and lower "submissive" and "optimistic" scores may reflect emotionally disregulated coping mechanisms which may lead to the risk of developing future depressive episodes. Lower "communication" in IPPA may show a disturbance in executive function of language. Lack of emotional awareness can be examined in line with alexithymia; but further studies are needed to explain these aspects.

Impulsivity, decision-making and risk-taking behaviour in bipolar disorder: a systematic review and meta-analysis

Despite the robust body of work on cognitive aspects of bipolar disorder (BD), a clear profile of associated impairments in impulsivity, decision-making and risk-taking from studies that use behavioural measures has yet to be established. A systematic review, across four electronic databases (PsycINFO, MEDLINE/PubMed, ScienceDirect and Scopus), of literature published between January 1999 and December 2018 was carried out in accordance with the PRISMA statement. The protocol was registered on PROSPERO (CRD42018114684). A fixed-effect and random-effects meta-analysis using the Hedges' g (ES) estimate was performed. The analysis revealed significant impairment in BD individuals with medium effect sizes in various aspects of impulsivity - response inhibition (ES = 0.49; p < 0.0001), delay of gratification (ES = 0.54; p < 0.0001) and inattention (ES = 0.49; p < 0.0001) - and in decision-making (ES = 0.61, p = 0.0002), but no significant impairment in risk-taking behaviour (ES = 0.41; p = 0.0598). Furthermore, we found significant heterogeneity between studies for decision-making and risk-taking behaviour but not for impulsivity. Impaired risk-taking behaviour was significant in a subgroup of BD-I and euthymic individuals (ES = 0.92; p < 0.0001) with no significant heterogeneity. A stratification analysis revealed comparable results in euthymic and non-euthymic individuals for impulsivity. Our findings suggest that behaviour impulsivity is elevated in all phases of BD, representing a core and clinically relevant feature that persists beyond mood symptoms. More studies about decision-making and risk-taking are necessary to establish if they are impaired in BD and to analyze the role of mood state.

Decreased motor impulsivity following chronic lithium treatment in male rats is associated with reduced levels of pro-inflammatory cytokines in the orbitofrontal cortex

Lithium's efficacy in reducing both symptom severity in bipolar disorder (BD) and suicide risk across clinical populations may reflect its ability to reduce impulsivity. Changes in immune markers are associated with BD and suicidality yet their exact role in symptom expression remains unknown. Evidence also suggests that lithium may decrease levels of pro-inflammatory cytokines in the periphery and central nervous system, and that such changes are related to its therapeutic efficacy. However, issues of cause and effect are hard to infer from clinical data alone. Here, we investigated the effects of chronic dietary lithium treatment on rats' performance of the 5-Choice Serial Reaction Time Task (5CSRTT), a well-validated operant behavioural task measuring aspects of impulsivity, attention and motivation. Male Long-Evans rats received a diet supplemented with 0.3% LiCl (n = 13), or the equivalent control diet (n = 16), during behavioural testing. Blood and brain tissue samples were assayed for a wide range of cytokines once any changes in impulsivity became significant. After 12 weeks, chronic lithium treatment reduced levels of motor impulsivity, as indexed by premature responses in the 5CSRTT; measures of sustained attention and motivation were unaffected. Plasma levels of IL-1β, IL-10 and RANTES (CCL-5) were reduced in lithium-treated rats at this time point. IL-1β, IL-6 and RANTES were also reduced selectively within the orbitofrontal cortex of lithium-treated rats, whereas cytokine levels in the medial prefrontal cortex and nucleus accumbens were comparable with control subjects. These results are consistent with the hypothesis that lithium may improve impulse control deficits in clinical populations by minimising the effects of pro-inflammatory signalling on neuronal activity, particularly within the orbitofrontal cortex.

Borderline patients have difficulties describing feelings; bipolar II patients describe difficult feelings. An alexithymia study

OBJECTIVE

Apparent similarities between borderline personality disorder (BPD) and bipolar II disorder (BIP-II) contribute to clinical difficulties in distinguishing between the disorders. Here, we aimed to explore how subjective Difficulties with the Identification and Description of Feelings (DIDF), a major constituent of the alexithymia construct and assessed as a part of the Toronto Alexithymia Scale (TAS), are related to relationship problems and health complaints in these groups.

METHODS

Twenty-two patients with BPD; 22 patients with BIP-II; and 23 healthy controls (HC) completed TAS. Health complaints, including symptoms associated with mood swings, were assessed with the Giessener Subjective Complaints List (Giessener Beschwerdebogen-GBB), and relationship problems with the Health of the Nation Outcome scale, Relationship item (HoNOSR). Bivariate correlations were run.

RESULTS

Both patient groups had high DIDF and GBB scores. In BPD only, there was a significant positive correlation between DIDF and HoNOSR. In BIP-II only, there was a significant positive correlation between DIDF and GBB total score. In BIP-II, DIDF correlated highly with those GBB subscales assessing symptoms typically occurring during bipolar mood swings (cardiovascular and gastrointestinal symptoms, exhaustion).

CONCLUSION

Our results suggest that in BPD, high DIDF scores represent genuine problems with identifying and describing emotions which are expected to correlate with relationship problems. In BIP-II, high DIDF scores could potentially represent difficulties with understanding the unpredictable symptoms of bipolar mood swings. The findings suggest that difficulties with identifying and describing feelings in patients should be carefully explored to increase the validity of the diagnostic evaluation.

Investigation of structure-function correlation among the young offspring of patients with bipolar disorder

Bipolar disorder (BD) has been associated with impaired executive functioning and integrity of fronto-limbic white matter tracts. The evaluation of these factors in young offspring of patients with BD (BDoff) as a high-risk group offers an opportunity to investigate factors that could predict vulnerability to the disorder. This study aims to examine the correlation between neurocognition and neuroimaging findings to evaluate the potential for these findings as biomarkers for the early recognition of BD. We enrolled BDoff (n = 16) who were aged between 12 and 18. Participants were assessed using clinical and neurocognitive tests. In addition, structural brain magnetic resonance and diffusion tensor imaging data were obtained. Mean fractional anisotropy (FA) and mean diffusivity (MD) values of the superior longitudinal fasciculus (SLF) and cingulum were extracted and correlations with neuropsychological data were analyzed. FA values in the SLF were negatively correlated with Stroop interference, the Wisconsin Card Sorting Test, and the Trail Making Test (B-A) scores. MD values in the cingulum were inversely correlated with the Child and Youth Resilience Measure and positively correlated with higher scores on the Barratt Impulsiveness Scale-Attentional. These findings provide a link between features of the brain and cognitive dysfunction in BDoff.

Cannabis use: A co-existing condition in first-episode bipolar mania patients

BACKGROUND

An association between first-episode presentation of bipolar mania and concurrent cannabis use disorder has been well established in the current literature (Bally et al., 2014, Baethge et al., 2008). Previous studies have shown that 30-70% of patients admitted for a first manic episode had concurrent cannabis use (Bally et al., 2014). The exact mechanism of this association has yet to be confirmed.

AIMS

We aim to evaluate the prevalence of cannabis use in patients with bipolar disorder (BD) admitted to UTHealth Harris County Psychiatric Center (HCPC) for a first manic episode.

METHODS

In this retrospective cohort study, 15,969 inpatient records of patients admitted to HCPC between 2012-2013 were examined to identify patients admitted with a first manic episode according to ICD-9 criteria (single episode mania). The prevalence of multiple sociodemographic and clinical variables including cannabis positivity in urine drug screening (UDS) were examined.

RESULTS

Twenty patients were admitted for a first manic episode. Half of the patients were females; mean age was 28.65 ± 10.56 years and mean length of stay (LOS) was 7.15 ± 3.72 days. Fifteen patients received a UDS. Of these fifteen, seven were positive for cannabinoids (47%). One patient was positive for phencyclidine (in addition to cannabis) and one patient was positive for amphetamine (but not cannabis).

CONCLUSIONS

The prevalence of cannabis use was higher in first-episode mania patients compared to the general population. The influence of cannabis on the first episode of mania requires additional study.

ADHD with Comorbid Bipolar Disorders: A Systematic Review of Neurobiological, Clinical and Pharmacological Aspects Across the Lifespan

BACKGROUND

Attention deficit hyperactivity (ADHD) disorder is a neurodevelopmental disorder characterized by inattention, hyperactivity, disruptive behaviour, and impulsivity. Despite considered typical of children for a long time, the persistence of ADHD symptoms in adulthood gained increasing interest during the last decades. Indeed, its diagnosis, albeit controversial, is rarely carried out even because ADHD is often comorbid with several other psychiatric diosrders, in particular with bipolar disorders (BDs), a condition that complicates the clinical picture, assessment and treatment.

AIMS

The aim of this paper was to systematically review the scientific literature on the neurobiological, clinical features and current pharmacological management of ADHD comorbid with BDs across the entire lifespan, with a major focus on the adulthood.

DISCUSSION

The pharmacology of ADHD-BD in adults is still empirical and influenced by the individual experience of the clinicians. Stimulants are endowed of a prompt efficacy and safety, whilst non-stimulants are useful when a substance abuse history is detected, although they require some weeks in order to be fully effective. In any case, an in-depth diagnostic and clinical evaluation of the single individual is mandatory.

CONCLUSION

The comorbidity of ADHD with BD is still a controversial matter, as it is the notion of adult ADHD as a distinct nosological category. Indeed, some findings highlighted the presence of common neurobiological mechanisms and overlapping clinical features, although disagreement does exist. In any case, while expecting to disentangle this crucial question, a correct management of this comorbidity is essential, which requires the co-administration of mood stabilizers. Further controlled clinical studies in large samples of adult ADHD-BD patients appear extremely urgent in order to better define possible therapeutic guidelines, as well as alternative approaches for this potentially invalidating condition.

Delay discounting abnormalities are seen in first-episode schizophrenia but not in bipolar disorder

Delay discounting (DD) is the phenomenon of individuals discounting future rewards as a function of time. It has been studied extensively in chronic schizophrenia (SZ) and the results of these studies have been variable. Comorbidity in chronic samples could be one reason for the mixed findings and studies in first-episode (FE) samples are surprisingly lacking. Bipolar disorder (BP) which shares some genetic and symptom features with SZ could serve as an interesting comparison group for DD but has been underexplored. Here we present the first study that combines FE SZ, FE BP with psychotic features, as well as healthy controls and study DD with two versions of the task. We found that SZ showed steeper discounting than HC and BP on the well-validated Kirby DD task. SZ showed no difference than HC on a separate DD task with smaller rewards presented with decimal places and shorter delays. As a preliminary finding, DD was found to be positively related to positive symptoms in FE SZ, while no relationship was found between negative symptoms and DD. In addition, we found comparable DD in BP compared to HC. Ultimately, our data may help elucidate the psychopathology in SZ and BP during intertemporal decision making.

Delay Discounting as a Transdiagnostic Process in Psychiatric Disorders: A Meta-analysis

IMPORTANCE

Delay discounting is a behavioral economic index of impulsive preferences for smaller-immediate or larger-delayed rewards that is argued to be a transdiagnostic process across health conditions. Studies suggest some psychiatric disorders are associated with differences in discounting compared with controls, but null findings have also been reported.

OBJECTIVE

To conduct a meta-analysis of the published literature on delay discounting in people with psychiatric disorders.

DATA SOURCES

PubMed, MEDLINE, PsycInfo, Embase, and Web of Science databases were searched through December 10, 2018. The psychiatric keywords used were based on DSM-IV or DSM-5 diagnostic categories. Collected data were analyzed from December 10, 2018, through June 1, 2019.

STUDY SELECTION

Following a preregistered Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) protocol, 2 independent raters reviewed titles, abstracts, and full-text articles. English-language articles comparing monetary delay discounting between participants with psychiatric disorders and controls were included.

DATA EXTRACTION AND SYNTHESIS

Hedges g effect sizes were computed and random-effects models were used for all analyses. Heterogeneity statistics, one-study-removed analyses, and publication bias indices were also examined.

MAIN OUTCOMES AND MEASURES

Categorical comparisons of delay discounting between a psychiatric group and a control group.

RESULTS

The sample included 57 effect sizes from 43 studies across 8 diagnostic categories. Significantly steeper discounting for individuals with a psychiatric disorder compared with controls was observed for major depressive disorder (Hedges g = 0.37; P = .002; k = 7), schizophrenia (Hedges g = 0.46; P = .004; k = 12), borderline personality disorder (Hedges g = 0.60; P < .001; k = 8), bipolar disorder (Hedges g = 0.68; P < .001; k = 4), bulimia nervosa (Hedges g = 0.41; P = .001; k = 4), and binge-eating disorder (Hedges g = 0.34; P = .001; k = 7). In contrast, anorexia nervosa exhibited statistically significantly shallower discounting (Hedges g = -0.30; P < .001; k = 10). Modest evidence of publication bias was indicated by a statistically significant Egger test for schizophrenia and at the aggregate level across studies.

CONCLUSIONS AND RELEVANCE

Results of this study appear to provide empirical support for delay discounting as a transdiagnostic process across most of the psychiatric disorders examined; the literature search also revealed limited studies in some disorders, notably posttraumatic stress disorder, which is a priority area for research.

Neural correlates of response inhibition in patients with bipolar disorder during acute versus remitted phase

Objectives: Elevated behavioural impulsivity has been shown to be a core feature of bipolar disorder. However, no study has so far investigated impulsivity-related brain activation in patients with BD during acute versus remitted phase. To address the question whether elevated behavioural impulsivity and its differential neural pathways is a state or trait marker of BD, we employed a combined stop signal-go/no-go task in 30 controls, and 37 depressed and 15 remitted patients who were retested.Methods: Frontal brain activation was recorded using near-infrared spectroscopy.Results: Behaviourally, we found increased impulsivity as indexed by higher stop signal reaction time for patients in their depressed phase while remitted patients did not differ from controls in any measure. In contrast, brain activation measurements revealed an opposite pattern: compared to controls, depressed patients did not show significant differences, while the remitted group displayed significantly decreased activation in bilateral prefrontal cortex during successful inhibition. Analysis of the remaining conditions (go, no-go, unsuccessful inhibition) did not reveal significant differences.Conclusions: Therefore, behavioural impulsivity and prefrontal hypoactivation do not seem to be a trait marker of BD. As only successful inhibition differentiated between groups, a specific dysfunction of this inhibitory process and its neural pathway may be postulated in BD.

Relationship Between Impulsivity and Clinical and Sociodemographic Variables Among Lebanese Patients With Bipolar Disorder: Results of a Cross-Sectional Study

Impulsivity is a psychiatric symptom that seems to be more prevalent in some mental disorders such as bipolar disorders (BDs). It is a trait that seems to be influenced by many clinical and sociodemographic variables across BD. To examine the relationship between impulsivity and these variables, we performed a cross-sectional study on 50 patients diagnosed with BD and 50 healthy subjects. Both groups were administered the Barratt Impulsiveness Scale; the Structural Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, 5th Edition, for borderline personality disorder; the Beirut District Scale; and the Athens Insomnia Scale to assess impulsivity, borderline personality disorder, psychological distress, and sleep disturbances, respectively. A significantly higher nonplanning impulsivity (p = 0.001), motor impulsivity (p < 0.0001), total impulsivity (p < 0.0001), body mass index (p < 0.0001), and insomnia (p = 0.002) were found in subjects with BDs compared with healthy ones. Exposure to violence (odds ratio [OR] = 7.63), the loss of a parent (OR = 3.83), being a current smoker (OR = 14.56), and a higher motor impulsivity score (OR = 1.27) were all significantly associated with the presence of BD. Impulsivity was shown to be strongly associated with the presence of a diagnosis of BD, and further studies are warranted to fully characterize it through the course of the illness.

Impulsivity and Behavior-Dependent Life Events Mediate the Relationship of Reward Sensitivity and Depression, but Not Hypomania, Among at-Risk Adolescents

Both reward sensitivity and impulsivity are related to the development and course of bipolar spectrum disorders (BSDs) and have been implicated in other disorders and negative functional outcomes such as substance abuse, obesity, suicidal behaviors, and risk-taking. Furthermore, according to the transactional component of the Behavioral Approach System (BAS)/reward hypersensitivity theory of BSDs, people with reward hypersensitivity should experience more BAS-relevant events, and thus, are more vulnerable to mood symptoms and episodes via stress generation. Impulsivity may exacerbate stress generation in individuals at risk for BSDs based on exhibiting reward hypersensitivity. The current study examined whether impulsivity explained the generation of stress and subsequent mood symptoms beyond what is explained by reward sensitivity alone. Participants were 131 Moderate BAS and 216 High BAS sensitivity adolescents (M = 18.43 years, SD = 1.40), who completed baseline measures of reward sensitivity and impulsivity, as well as follow-up measures of life events and mood symptoms. Results from linear regression analyses indicated that higher baseline impulsivity predicted behavior-dependent, but not behavior-independent, life events. Furthermore, path analyses suggested that the effect of BAS group on depression symptoms at next follow-up was partly explained via the indirect effect of impulsivity and negative behavior-dependent life events. We did not find these effects for behavior-independent or positive-dependent events or for prediction of hypomanic symptoms. The findings suggest that impulsivity may account for stress generation of negative events that precede depression.

Impulsivity differences between bipolar and unipolar depression

BACKGROUND

Even though particularly bipolar depression and unipolar depression seem to be similar, they show differences in terms of the etiology, phenomenology, course, and treatment process. Bipolar depression is associated with mood lability, motor retardation, and hypersomnia to a larger extent. Early age of onset, a high frequency of depressive episodes, and history of bipolar disease in the family are suggestive of bipolar disorder (BD) rather than major depression. Bipolar and unipolar disorders are also associated with increased impulsivity during illness episodes. However, there is little information about impulsivity during euthymia in these mood disorders. The aim of this study was to illustrate the difference in impulsivity in euthymic bipolar and unipolar patients.

MATERIALS AND METHODS

Impulsivity was evaluated by the Barratt Impulsiveness Scale (BIS-11A), in 78 interepisode BD patients, 72 interepisode unipolar disorder patients, and 70 healthy controls. The diagnosis was established by severe combined immunodeficiency. One-way between-groups ANOVA was used to compare the BIS-11A mean scores for all three groups.

RESULTS

Impulsivity scores of the bipolar and unipolar disorder patients were significantly higher than controls on total and all subscales measures. There was no difference between the bipolar and unipolar disorder groups on total, attentional, and nonplanning impulsivity measures. However, BD patients scored significantly higher than the unipolar patients on motor impulsivity measures.

CONCLUSIONS

Both interepisode bipolar and unipolar disorder patients had increased impulsivity compared to healthy individuals. There was no significant difference on attention and nonplanning impulsivity subscales; however, on the motor subscale, bipolar patients were more impulsive than unipolar disorder patients.

The Oxford study of Calcium channel Antagonism, Cognition, Mood instability and Sleep (OxCaMS): study protocol for a randomised controlled, experimental medicine study

Background

The discovery that voltage-gated calcium channel genes such as CACNA1C are part of the aetiology of psychiatric disorders has rekindled interest in the therapeutic potential of L-type calcium channel (LTCC) antagonists. These drugs, licensed to treat hypertension and angina, have previously been used in bipolar disorder, but without clear results. Neither is much known about the broader effects of these drugs on the brain and behaviour.

Methods

The Oxford study of Calcium channel Antagonism, Cognition, Mood instability and Sleep (OxCaMS) is a high-intensity randomised, double-blind, placebo-controlled experimental medicine study on the effect of the LTCC antagonist nicardipine in healthy young adults with mood instability. An array of cognitive, psychiatric, circadian, physiological, biochemical and neuroimaging (functional magnetic resonance imaging and magnetoencephalography) parameters are measured during a 4-week period, with randomisation to drug or placebo on day 14. We are interested in whether nicardipine affects the stability of these measures, as well as its overall effects. Participants are genotyped for the CACNA1C risk polymorphism rs1006737.

Discussion

The results will clarify the potential of LTCC antagonists for repurposing or modification for use in psychiatric disorders in which cognition, mood and sleep are affected.

Trial registration

ISRCTN, ISRCTN33631053. Retrospectively registered on 8 June 2018 (applied 17 May 2018).

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3175-0) contains supplementary material, which is available to authorized users.

Impulsivity and its association with childhood trauma experiences across bipolar disorder, attention deficit hyperactivity disorder and borderline personality disorder

BACKGROUND

Impulsivity is a core feature of the attention-deficit/hyperactivity disorder (ADHD) and is one of the DSM-V diagnostic criteria for borderline personality disorder (BPD). Impulsivity is also present in bipolar disorder (BD). Impulsivity has been linked to adverse behavior (suicidality,…) and to traumatic childhood experiences. Our study explored impulsivity in BPD, BD, ADHD and healthy controls (CTRL) and investigated the impact of early trauma on impulsivity.

METHODS

744 patients with BD (n = 276), BPD (n = 168), ADHD (n = 173) or a combination (BPD_BD, n = 29; BPD_ADHD, n = 94, BD_BPD_ADHD n = 13) and 47 controls were included. All subjects were completed the Baratt Impulsivity Scale (BIS-10) and the Childhood Trauma Questionnaire (CTQ).

RESULTS

BD reported the same levels of impulsiveness as CTRL. When BPD and BD are co-morbid, impulsivity increased to reach the level of BPD. Impulsiveness was significantly associated to traumatic childhood event for BD and CTRL, not for BPD and AHDH.

LIMITATIONS

Impulsivity was assessed on the basis of a self-report questionnaire and not by the mean of an objective measure such as a neuropsychological test. Moreover, we don't know what treatment our pathological subjects were receiving. But, ADHD and BPD, despite the probable treatment, were more impulsive than healthy CTRLs who did not take medications.

CONCLUSIONS

Impulsivity is probably not a feature of BD but is associated with the presence of traumatic childhood experiences, especially for euthymic patients, unlike BPD and ADHD. So, it seems essential to assess the presence of early trauma to reduce the impulsivity and improve the evolution of BD.

Subthalamic Nucleus Activation Occurs Early during Stopping and Is Associated with Trait Impulsivity

The subthalamic nucleus (STN) is thought to be a central regulator of behavioral inhibition, which is thought to be a major determinant of impulsivity. Thus, it would be reasonable to hypothesize that STN function is related to impulsivity. However, it has been difficult to test this hypothesis because of the challenges in noninvasively and accurately measuring this structure's signal in humans. We utilized a novel approach for STN signal localization that entails identifying this structure directly on fMRI images for each individual participant in native space. Using this approach, we measured STN responses during the stop signal task in a sample of healthy adult participants. We confirmed that the STN exhibited selective activation during "Stop" trials. Furthermore, the magnitude of STN activation during successful Stop trials inversely correlated with individual differences in trait impulsivity as measured by a personality inventory. Time course analysis revealed that early STN activation differentiated successful from unsuccessful Stop trials, and individual differences in the magnitude of STN activation inversely correlated with stop signal RT, an estimate of time required to stop. These results are consistent with the STN playing a central role in inhibition and related behavioral proclivities, with implications for both normal range function and clinical syndromes of inhibitory dyscontrol. Moreover, the methods utilized in this study for measuring STN fMRI signal in humans may be gainfully applied in future studies to further our understanding of the role of the STN in regulating behavior and neuropsychiatric conditions.

Validation of the Barratt Impulsiveness Scale- short form among Indian adolescents

BACKGROUND

Impulsivity is widely assessed with a 30 item self-report measure known as the Barrratt Impulsiveness Scale (BIS-11). Further development involved creation of an abbreviated version, called Barratt Impulsiveness Scale- short form (BIS-15; Spinella, 2007) from the original BIS-11. Unlike the original BIS-11, BIS-15 has not undergone sufficient cross cultural validation especially among the adolescent population.

AIM

To evaluate the factor structure and psychometric properties of BIS-15 among school and college attending Indian adolescents.

METHOD

A total of 1806 adolescents (females = 48%, mean age = 17.14 years) completed BIS-15 questionnaire, strengths and difficulties questionnaire (SDQ) and a risk taking questionnaire that assessed adolescents level of involvement in two protypical risky behaviours- substance use and unsafe sexual behaviours.

RESULTS

The results of the principal component analysis of BIS-15 items revealed a three factor structure: attentional, motor and non-planning impulsivity. The internal consistency of BIS-15 was 0.79. The total score on BIS-15 was significantly associated with the externalizing, internalizing and total difficulty score on SDQ. Significant associations were observed between BIS-15 total impulsivity score and the level of risk taking among adolescents. Further, the results also revealed gender variance in impulsivity scores where male adolescents scored higher on attentional and non-planning impulsivity as compared to female adolescents.

CONCLUSION

BIS-15 is a reliable measure of impulsivity that can be used with Indian adolescent population. It would be particularly more suitable for use in settings that require comprehensive assessment of trait impulsivity in shorter time duration and without burdening the participants.

Impulsivity predicts illness severity in long-term course of bipolar disorder: A prospective approach

BACKGROUND

Bipolar disorder is a common, severe and chronic mental illness. Despite this, predictors of illness severity remain poorly understood. Impulsivity is reported to be associated with bipolar disorder and aggravating comorbidities. This study therefore sought to examine the predictive value of impulsivity for determining illness severity in euthymic bipolar disorder patients.

METHODS

Baseline trait impulsivity of 120 bipolar euthymic patients (81 bipolar disorder I [68%], 80 female [67%]) and 51 healthy controls was assessed using Barratt Impulsiveness Scale 11. The impact of impulsivity on illness severity (measured with morbidity index) was prospectively tested in 97 patients with sufficient follow-up data (average observation time: 54.4 weeks), using linear regression analysis.

RESULTS

Barratt Impulsiveness Scale 11 total (β = 0.01; p < 0.01) and in particular Barratt Impulsiveness Scale 11 attentional subscale scores (β = 0.04; p < 0.001) predicted illness severity in bipolar disorder, while controlling for other clinical variables. Only age at onset persisted as an additional, but less influential predictor. Barratt Impulsiveness Scale 11 total scores and Barratt Impulsiveness Scale 11 attentional subscale scores were significantly higher in euthymic patients compared to controls. This was not observed for the motor or non-planning subscale scores.

LIMITATIONS

The average year-long observation time might not be long enough to account for the chronic course of bipolar disorder.

CONCLUSION

Trait impulsivity and particularly attentional impulsivity in euthymic bipolar patients can be strong predictors of illness severity in bipolar disorder. Future studies should explore impulsivity as a risk assessment for morbidity and as a therapeutic target in bipolar disorder patients.

Neurobiological Evidence for the Primacy of Mania Hypothesis

BACKGROUND

Athanasios Koukopoulos proposed the primacy of mania hypothesis (PoM) in a 2006 book chapter and later, in two peer-reviewed papers with Nassir Ghaemi and other collaborators. This hypothesis supports that in bipolar disorder, mania leads to depression, while depression does not lead to mania.

OBJECTIVE

To identify evidence in literature that supports or falsifies this hypothesis.

METHOD

We searched the medical literature (PubMed, Embase, PsycINFO, and the Cochrane Library) for peer-reviewed papers on the primacy of mania, the default mode function of the brain in normal people and in bipolar disorder patients, and on illusion superiority until 6 June, 2016. Papers resulting from searches were considered for appropriateness to our objective. We adopted the PRISMA method for our review. The search for consistency with PoM was filtered through the neurobiological results of superiority illusion studies.

RESULTS

Out of a grand total of 139 records, 59 were included in our analysis. Of these, 36 were of uncertain value as to the primacy of mania hypothesis, 22 favoured it, and 1 was contrary, but the latter pooled patients in their manic and depressive phases, so to invalidate possible conclusions about its consistency with regard to PoM. All considered studies were not focused on PoM or superiority illusion, hence most of their results were, as expected, unrelated to the circuitry involved in superiority illusion. A considerable amount of evidence is consistent with the hypothesis, although indirectly so.

LIMITATIONS

Only few studies compared manic with depressive phases, with the majority including patients in euthymia.

CONCLUSION

It is possible that humans have a natural tendency for elation/optimism and positive self-consideration, that are more akin to mania; the depressive state could be a consequence of frustrated or unsustainable mania. This would be consistent with PoM.

Developing Dimensional, Pandiagnostic Inhibitory Control Constructs With Self-Report and Neuropsychological Data

Trait markers, or intermediate phenotypes linking different units of analysis (self-report, performance) from the Research Domain Criteria (RDoC) matrix across populations is a necessary step in identifying at-risk individuals. In the current study, 150 healthy controls (HC) and 456 individuals with bipolar disorder (BD) Type I or II, NOS (not otherwise specified) or Schizoaffective BD completed self-report neuropsychological tests of inhibitory control (IC) and executive functioning. Bifactor analyses were used to examine the factor structure of these measures and to evaluate for invariance across groups. Bifactor analyses found modest convergence of items from neuropsychological tests and self-report measures of IC among HC and BD. The factor scores showed evidence of a general IC construct (i.e., subdomain) across measures. Importantly, invariance testing indicated that the same construct was measured equally well across groups. Groups differed on the general factor for three of the four scales. Convergence on a general IC factor and invariance across diagnosis supports the use of combined dimensional measures to identify clinical risk and highlights how prospective RDoC studies might integrate units of analysis.

Higher Impulsivity and HIV-Risk Taking Behaviour in Males with Alcohol Dependence Compared to Bipolar Mania: A Pilot Study

To study the association of impulsivity, high-risk behaviours and incidence of HIV infection in patients with alcohol dependence and bipolar mania. This was a cross-sectional hospital-based pilot study and the sample consisted of male patients divided into three groups: 25 patients with alcohol dependence and 25 with bipolar mania as per ICD-10 Diagnostic Criteria for Research and 25 normal controls. Severity of Alcohol Dependence Questionnaire (SADQ) and Young Mania Rating Scale (YMRS) were administered on alcohol dependent and bipolar patients, respectively. All three groups were rated on Barrett's Impulsivity Scale (BIS) and HIV Risk-taking Behaviour Scale (HRBS). None of the patients tested positive for either HIV 1 or 2. BIS motor impulsivity, BIS total score and HRBS total score were significantly higher in alcohol dependent patients as compared to bipolar mania patients. In the Alcohol dependent group, BIS score significantly correlated with education years, age of onset of alcohol use and SADQ, whereas, HRBS total score significantly correlated with SADQ scores. In the bipolar mania group, BIS significantly correlated with YMRS, and total number of episodes, whereas, there was no significant correlation of HRBS total score with any clinical variable. The findings of this pilot study underscore the link between alcohol use disorder and the impulsive behaviours that can lead to HIV infection, and highlight that those risks are higher for individuals with alcohol dependency than for individuals with bipolar disorder.

Increased reward-oriented impulsivity in older bipolar patients: A preliminary study

OBJECTIVE

Impulsivity is a well-established trait of bipolar disorder (BD) that persists across mood phases. It is, however, still unknown whether, in BD, impulsivity remains stable or varies in intensity over the lifespan. This cross-sectional study compared impulsive behavior in older euthymic BD patients and healthy individuals using a range of self-rating and behavioral measures of impulsivity.

METHODS

28 BD patients (56.07 ± 4.08 years, 16 women) and 15 healthy controls (HC; 55.1 ± 3.95 years, 6 women) were administered the Barratt Impulsivity Scale (BIS) and selected tasks of the Cambridge Neuropsychological Test Automated Batter (CANTAB) reflecting impulsivity. Multivariate analysis of variance controlled for age compared impulsivity measures across BD and HC.

RESULTS

BD patients displayed poor decision making, risk taking, and increased delay aversion. Other measures of impulsivity such as response inhibition, sustained cognitive control, and BIS scores were, overall, comparable between BD and HC.

CONCLUSIONS

These preliminary findings suggest that, in BD, aspects of impulsivity related to reward-based decision making persist into late adulthood. Large scale, longitudinal studies are needed to evaluate the relationship of age to impulsivity over time, and explore the link between impulsivity and illness progression in elderly individuals with BD.

Revisiting the wandering womb: Oxytocin in endometriosis and bipolar disorder

Hippocrates attributed women's high emotionality - hysteria - to a 'wandering womb'. Although hysteria diagnoses were abandoned along with the notion that displaced wombs cause emotional disturbance, recent research suggests that elevated levels of oxytocin occur in both bipolar disorder and endometriosis, a gynecological condition involving migration of endometrial tissue beyond the uterus. We propose and evaluate the hypothesis that elevated oxytocinergic system activity jointly contributes to bipolar disorder and endometriosis. First, we provide relevant background on endometriosis and bipolar disorder, and then we examine evidence for comorbidity between these conditions. We next: (1) review oxytocin's associations with personality traits, especially extraversion and openness, and how they overlap with bipolar spectrum traits; (2) describe evidence for higher oxytocinergic activity in both endometriosis and bipolar disorder; (3) examine altered hypothalamic-pituitary-gonadal axis functioning in both conditions; (4) describe data showing that medications that treat one condition can improve symptoms of the other; (5) discuss fitness-related impacts of endometriosis and bipolar disorder; and (6) review a pair of conditions, polycystic ovary syndrome and autism, that show evidence of involving reduced oxytocinergic activity, in direct contrast to endometriosis and bipolar disorder. Considered together, the bipolar spectrum and endometriosis appear to involve dysregulated high extremes of normally adaptive pleiotropy in the female oxytocin system, whereby elevated levels of oxytocinergic activity coordinate outgoing sociality with heightened fertility, apparently characterizing, overall, a faster life history. These findings should prompt a re-examination of how mind-body interactions, and the pleiotropic endocrine systems that underlie them, contribute to health and disease.

Reported maladaptive decision-making in unipolar and bipolar depression and its change with treatment

Mood disorder patients frequently experience difficulty making decisions and may make sub-optimal decisions with adverse life consequences. However, patients' styles for decision-making when ill and after treatment have received little study to date. We assessed healthy controls (HC, n = 69) and patients with major depressive disorder (MDD, n = 61) or bipolar disorder (BP, n = 26) in a current major depressive episode using the Melbourne Decision-making Questionnaire. A subset of participants was re-evaluated after completing six weeks of pharmacotherapy. HC demonstrated significantly greater use of the healthy vigilance style, and significantly lower use of maladaptive decision-making styles, than the MDD and depressed BP patients. After six weeks of treatment, neither the MDD nor BP patients reported meaningful improvements in the vigilance style of decision-making, but scores on most maladaptive decision-making styles declined. BP patients who remitted reported significantly lower buckpassing and procrastination scores than healthy controls. Among MDD patients, however, the maladaptive passive buckpassing style of decision-making did not significantly diminish. For MDD patients, reported decision-making styles may remain impaired even after achieving remission. Among BP patients, low levels of adaptive vigilance decision-making may be a trait component of the illness, whereas for MDD patients, reported maladaptive passive decision-making styles are persistent.

Are self-rated and behavioural measures of impulsivity in bipolar disorder mainly related to comorbid substance use problems?

INTRODUCTION

Impulsivity is a multidimensional feature observed in bipolar disorder (BD) and substance use disorder (SUD). We previously found a relationship between SUD and risk taking in BD. It is still unclear whether self-rated and behavioral impulsivity measures differ between BD with and without comorbid SUD, or are specific to BD.

METHODS

93 adults with BD with comorbid SUD, 91 BD without SUD, and 93 healthy controls (HC) were administered the Barratt Impulsivity Scale (BIS), the Behavioral Inhibition/Behavioral Activation System Scale (BIS/BAS), and the Cambridge Neuropsychological Test Automated Battery. Analyses compared impulsivity measures across groups controlling for age. Discriminant function analyses (DFA) assessed the combination of variables effectively predicting group membership.

RESULTS

BD displayed increased BIS, BIS/BAS scores, reduced performance on the Cambridge Gambling and Rapid Visual Processing, and Affective Go/No-Go tasks compared to HC. Comparisons between BD with and without SUD showed increased BIS Motor impulsiveness. The overall predictive power of DFA was weak.

CONCLUSIONS

Some facets of impulsivity are a core trait of BD and are partially independent from the presence of SUD. Motor impulsiveness may be distinctive of BD+SUD. More research is needed to understand the role of impulsive behaviors as risk factors for relapse in SUD.