A preliminary investigation of impulsivity, aggression and white matter in patients with bipolar disorder and a suicide attempt history

A sense of urgency: Trait impulsivity in co-occurring bipolar and alcohol use disorder

BACKGROUND

Bipolar disorder (BD) and alcohol use disorder (AUD) often co-occur, with BD + AUD characterized by higher levels of impulsivity relative to either disorder alone. Emotional facets of impulsivity (e.g., "urgency," measured by the UPPS-P), however, remain underexplored in this population and could have distinct associations with clinical correlates.

METHODS

This cross-sectional study used a two-by-two (BDxAD) factorial design, including groups with BD + AD (n = 28), BD (n = 29), AD (n = 28), and healthy controls (HC) (n = 27), to identify between-group differences among the five subscales of the UPPS-P. Associations of UPPS-P subscales with Barratt Impulsiveness Scale (BIS) total scores and clinical variables of interest were also examined.

RESULTS

BD + AD had the highest scores for every UPPS-P subscale but Sensation Seeking, with the Positive and Negative Urgency subscales having the largest main effects for both BD and AD. BIS-11 total scores were most correlated with the urgency subscales of the UPPS-P. Negative Urgency was found to be uniquely relevant to clinical measures in the BD + AD group. Rapid cycling was associated with both urgency subscales and BIS-11 scores, and the Alcohol Dependence Scale was most correlated with the Premeditation subscale.

LIMITATIONS

Cross sectional design and predominantly white sample.

CONCLUSIONS

Unlike the BIS-11, UPPS-P is able to distinguish emotional from nonemotional facets of impulsivity, something especially relevant to people with co-occurring BD + AD, where fluid emotionality is a key part of symptom presentation. For this reason, the UPPS-P should be utilized in future studies and clinical settings measuring trait impulsivity in this population.

Reduced myelin content in bipolar disorder: A study of inhomogeneous magnetization transfer

BACKGROUND

Previous neuroimaging and pathological studies have found myelin-related abnormalities in bipolar disorder (BD), which prompted the use of magnetic resonance (MR) imaging technology sensitive to neuropathological changes to explore its neuropathological basis. We holistically investigated alterations in myelin within BD patients by inhomogeneous magnetization transfer (ihMT), which is sensitive and specific to myelin content.

METHODS

Thirty-one BD and 42 healthy controls (HC) were involved. Four MR metrics, i.e., ihMT ratio (ihMTR), pseudo-quantitative ihMT (qihMT), magnetization transfer ratio and pseudo-quantitative magnetization transfer (qMT), were compared between groups using analysis methods based on whole-brain voxel-level and white matter regions of interest (ROI), respectively.

RESULTS

The voxel-wise analysis showed significantly inter-group differences of ihMTR and qihMT in the corpus callosum. The ROI-wise analysis showed that ihMTR, qihMT, and qMT values in BD group were significantly lower than that in HC group in the genu and body of corpus callosum, left anterior limb of the internal capsule, left anterior corona radiate, and bilateral cingulum (p < 0.001). And the qihMT in genu of corpus callosum and right cingulum were negatively correlated with depressive symptoms in BD group.

LIMITATIONS

This study is based on cross-sectional data and the sample size is limited.

CONCLUSION

These findings suggest the reduced myelin content of anterior midline structure in the bipolar patients, which might be a critical pathophysiological feature of BD.

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.

Benson relaxation technique to address sleep quality and aggression among patients with bipolar type I disorder: A randomized clinical trial study

Purpose

The present research was conducted to assess the effect of the Benson relaxation technique on sleep quality and aggression among patients with bipolar type I disorder.

Methods

This study was conducted using a randomized clinical trial design with the participation of 60 patients with bipolar type I disorder (30 participants in each group) in Mashhad, Iran (IRCT20220108053659N1). The intervention group received the Benson relaxation technique for 21 days in a row, twice a day (in the morning and evening), under the supervision of an expert psychiatric nurse (On the first day, instruction was given on implementing BRT. In the subsequent days of the intervention, the nurse stayed by the patient's bedside for the entire relaxation process). Aggression and sleep quality were assessed using the Buss-Perry Aggression Questionnaire and Pittsburgh Sleep Quality Index, respectively, before and one week after the completion of the intervention. Data were analyzed using descriptive and inferential statistics (Chi-squared, Fisher's exact test, independent sample t-test, and analysis of covariance).

Results

The participants in the present study were individuals of both genders aged 18 and above. Based on the results, both groups were homogeneous regarding demographic characteristics. Prior to the intervention, the two groups of control and intervention were not significantly different from each other in terms of sleep quality (p = 0.870) and aggression (p = 0.961). After the intervention, in an intergroup comparison, a significant difference was observed between the two groups in terms of the mean difference of aggression (p < 0.001) and sleep quality scores (p < 0.001).

Conclusion

Despite the favorable effect of this intervention, it is necessary to conduct more studies considering the broader aspects of interventions and related variables before including these interventions in the care plan of patients with bipolar type I disorder.

The Types of Psychosocial Factors Associated with Suicidality Outcomes for People Living with Bipolar Disorder: A Scoping Review

Bipolar Disorder is associated with high rates of suicidal thoughts, behaviors, and outcomes, yet the lived experience of suicidality and Bipolar Disorder is not particularly well understood. Understanding the role of psychosocial aetiologies in suicidality outcomes for those living with Bipolar Disorder is key for developing appropriately targeted interventions focusing on factors that are amenable to change. In line with PRISMA guidance, we conducted a scoping review to identify the types of psychosocial factors studied in relation to the experience of suicidality for people living with Bipolar Disorder diagnoses. Systematic literature searches identified a sample of 166 articles from which key study data were extracted and charted. A narrative synthesis of the reviewed literature is presented ordered by the factors investigated across studies, a frequency count of the types of psychological/social aetiologies studied, and a brief overview of the key findings for each aetiology. Most of the identified literature took the form of quantitative cross-sectional studies, with only one qualitative study and 18 quantitative prospective studies. The most studied aetiologies were trauma (specifically early adverse experiences and childhood traumas) and stressful life events, impulsivity (primarily subjective self-reported trait impulsivity), social support and functioning, and personality/temperament factors. Only six studies in the final sample reported basing their research questions and/or hypotheses on an explicit theoretical model of suicide. The literature was primarily focused on using self-report measurements of key aetiologies and on factors which lead to worsened suicidality rather than focusing on potentially protective or buffering factors. Future research needs to better justify the aetiologies investigated in relation to suicidality outcomes for people living with Bipolar Disorder, including a firmer basis in theory and hypothesis testing, more prospective designs, and the use of alternative assessments of psychosocial aetiologies in addition to self-report questionnaires.

Do bipolar disorder symptom profiles matter for suicide risk? A latent class approach to investigating differences in suicidal desire and acquired capability

INTRODUCTION

Depressive and mixed symptoms in bipolar disorder (BD) have been linked to higher suicide risk. Based on Klonsky and May's three-step theory and Joiner's Interpersonal Psychological Theory of Suicide, we hypothesized that patients diagnosed with BD who reported severe levels of depressive symptoms and mixed depressive and manic symptoms would also report higher levels of suicidal desire and acquired capability of suicide, as well as suicidal thoughts and behaviors.

METHODS

The sample included 177 outpatients diagnosed with BD. Latent class analysis was conducted to replicate the identified groups of a previously conducted study using a smaller but overlapping dataset. Between-class and pairwise analyses with measures of suicidal desire and acquired capability were conducted.

RESULTS

As expected, the classes characterized by severe depressive symptoms and mixed symptoms reported higher levels of suicidal desire. However, the results regarding acquired capability were less consistent.

CONCLUSION

Given the overall elevated suicide risk of BD and the consistent relationship between depressive symptoms and other strong correlates of suicide, clinicians who work with patients diagnosed with BD should closely monitor changes in their depressive symptoms.

Emotional urgency predicts bipolar symptoms, severity, and suicide attempt better than non-emotional impulsivity: a cross-sectional study

Introduction

Emotional urgency is an emotion-based subdimension of trait impulsivity that is more clinically relevant to psychopathology and disorders of emotion dysfunction than non-emotional subdimensions (i.e., lack of perseverance, sensation seeking, lack of premeditation). However, few studies have examined the relative effects of emotional urgency in bipolar disorder. This cross-sectional study aimed to establish the clinical relevance of emotional urgency in bipolar disorders by (1) explicating clinically relevant correlates of emotional urgency and (2) comparing its effects against non-emotional impulsivity subdimensions.

Methods and results

A total of 150 individuals with bipolar disorder were recruited between October 2021 and January 2023. Zero-order correlations found that emotional urgency had the greatest effect on bipolar symptoms (r = 0.37 to 0.44). Multiple two-step hierarchical regression models showed that (1) positive urgency predicted past manic symptomology and dysfunction severity (b = 1.94, p < 0.001 and 0.35 p < 0.05, respectively), (2) negative urgency predicted current depression severity, and (3) non-emotional facets of impulsivity had smaller effects on bipolar symptoms and dysfunction by contrast, and were non-significant factors in the final step of all regression models (b < 0.30, ns); Those who had a history of attempted suicide had significantly greater levels of emotional urgency (Cohen's d = -0.63).

Discussion

Notwithstanding the study's limitations, our findings expand status quo knowledge beyond the perennial relationship between non-emotion-based impulsivity and bipolar disorder and its implications.

Effects of sleep and impulsivity on suicidality in shift and non-shift workers

INTRODUCTION

Shift workers are known to have a higher suicide risk than non-shift workers. Sleep disturbance and impulsivity are also risk factors for suicidality. This study investigated the effects of poor sleep and impulsivity on suicidality in shift and non-shift workers.

METHODS

In total, 4572 shift workers (37.0 ± 9.84 years, 2150 males) and 2093 non-shift workers (37.8 ± 9.73 years, 999 males) participated in an online self-report survey. Suicidality was assessed using the Suicidal Behaviors Questionnaire. The Pittsburgh Sleep Quality Index was employed to explore subjective sleep quality, the Insomnia Severity Index to detect insomnia, the Epworth Sleepiness Scale (ESS) to evaluate excessive daytime sleepiness (EDS), the Center for Epidemiological Studies-Depression (CES-D) Scale to assess depressive symptoms, and the Impulsive Behavior Scale (UPPS-P) to explore impulsivity.

RESULTS

Shift workers showed poorer sleep quality, and greater impulsivity and suicidality, than non-shift workers. Impulsivity, sleep duration, sleep quality, and insomnia were significantly associated with suicidality, independent of depression. For both shift and non-shift workers, sleep quality moderated the association between impulsivity and suicidality. However, the moderating effects of sleep duration and EDS on the association between impulsivity and suicidality were apparent only in non-shift workers, while a moderating effect of insomnia was observed only in shift workers.

CONCLUSION

Shift work, sleep disturbances and impulsivity may exacerbate suicide risk. In addition, the interrelationships among insomnia, EDS, impulsivity, and suicidality may differ between shift and non-shift workers.

Alterations of insular dynamic functional connectivity and psychological characteristics in unmedicated bipolar depression patients with a recent suicide attempt

BACKGROUND

Mounting evidence showed that insula contributed to the neurobiological mechanism of suicidal behaviors in bipolar disorder (BD). However, no studies have analyzed the dynamic functional connectivity (dFC) of insular Mubregions and its association with personality traits in BD with suicidal behaviors. Therefore, we investigated the alterations of dFC variability in insular subregions and personality characteristics in BD patients with a recent suicide attempt (SA).

METHODS

Thirty unmedicated BD patients with SA, 38 patients without SA (NSA) and 35 demographically matched healthy controls (HCs) were included. The sliding-window analysis was used to evaluate whole-brain dFC for each insular subregion seed. We assessed between-group differences of psychological characteristics on the Minnesota Multiphasic Personality Inventory-2. Finally, a multivariate regression model was adopted to predict the severity of suicidality.

RESULTS

Compared to NSA and HCs, the SA group exhibited decreased dFC variability values between the left dorsal anterior insula and the left anterior cerebellum. These dFC variability values could also be utilized to predict the severity of suicidality (r = 0.456, p = 0.031), while static functional connectivity values were not appropriate for this prediction. Besides, the SA group scored significantly higher on the schizophrenia clinical scales (p < 0.001) compared with the NSA group.

CONCLUSIONS

Our findings indicated that the dysfunction of insula-cerebellum connectivity may underlie the neural basis of SA in BD patients, and highlighted the dFC variability values could be considered a neuromarker for predictive models of the severity of suicidality. Moreover, the psychiatric features may increase the vulnerability of suicidal behavior.

Beyond BMI: cardiometabolic measures as predictors of impulsivity and white matter changes in adolescents

Obesity is characterized by cardiometabolic and neurocognitive changes. However, how these two factors relate to each other in this population is unknown. We tested the association that cardiometabolic measures may have with impulse behaviors and white matter microstructure in adolescents with and without an excess weight. One hundred and eight adolescents (43 normal-weight and 65 overweight/obesity; 11-19 years old) were medically and psychologically (Temperament Character Inventory Revised, Three-Factor Eating Questionnaire-R18, Conners' Continuous Performance Test-II, Stroop Color and Word Test, Wisconsin Card Sorting Test, Kirby Delay Discounting Task) evaluated. A subsample of participants (n = 56) underwent a brain magnetic resonance imaging acquisition. In adolescents, higher triglycerides and having a body mass index indicative of overweight/obesity predicted a more impulsive performance in Conners' Continuous Performance Test-II (higher commission errors). In addition, higher glucose and diastolic blood pressure values predicted increments in the Three-Factor Eating Questionnaire-R18 emotional eating scale. Neuroanatomically, cingulum fractional anisotropy showed a negative relationship with glycated hemoglobin. The evaluation of the neurocognitive differences associated with obesity, usually based on body mass index, should be complemented with cardiometabolic measures.

Impulsivity as a mediator between childhood maltreatment and suicidal behavior: A systematic review and meta-analysis

Childhood maltreatment is a known risk factor for the development of suicidal behavior. Possible mediators of the association between childhood maltreatment and suicide have been analyzed. Some studies have considered impulsivity as one of these mediators, but there are no previous reviews on this topic. We, therefore, present a systematic review and mediation meta-analysis of the literature summarizing the evidence on impulsivity as a mediator of the relationship between childhood maltreatment and lifetime suicidal behavior. This review followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. The review was registered in the PROSPERO database. We searched PubMed, PsycINFO, WebOfScience, and EMBASE databases up to February 2021 to identify studies exploring the association between childhood maltreatment and suicide through impulsivity. Fourteen articles met the selection criteria and were included in the review. Seven articles could be included in the mediation meta-analysis. Impulsivity was a significant mediator of the relationship between childhood maltreatment and suicidal behavior in ten of the fourteen included studies. This result was confirmed using mediation meta-analysis (β = .06, 95% CI 0.03-0.10). Studies suggest that exposure to traumatic situations in childhood affects the proper neurobiological, cognitive, and affective development of individuals. This may increase impulsivity, which in turn would be related to an increased risk of suicide. The effects of childhood maltreatment and impulsivity may be both therapeutic targets of interest to reduce suicide rates.

Suicidal Ideation in Bipolar Disorder: The Relation with Clinical and Sociodemographic Variables

INTRODUCTION

Bipolar disorder (BD) has the highest risk of suicide among all mental disorders. Thus, identifying factors related to suicidal ideation is essential for a better assessment of the risk of suicide in BD.

OBJECTIVE

To analyze the relationship between suicidal ideation and clinical and sociodemographic characteristics in BD patients.

METHOD

This is a cross-sectional study that included eighty individuals with BD. Information regarding sociodemographic data and history of attempted suicide were collected, and the Hamilton Depression Scale, Young Mania Rating Scale, Positive And Negative Syndrome Scale/positive symptom subscale, Clinical Global Impressions Scale for use in bipolar illness, Insight Scale for Affective Disorders, and Barratt Impulsiveness Scale were administered. The presence and severity of suicidal ideation were assessed using the Beck Scale for Suicidal Ideation.

RESULTS

All regression models significantly predicted suicidal ideation. In the model that had the lowest AIC score and the highest cross-validity, the severity of depressive and of manic symptoms (standardized β = 0.49, p < 0.001; standardized β = 0.42, p = 0.007), the insight level (standardized β = - 0.38, p = 0.012) and previous suicide attempt (standardized β = 0.20, p = 0.036) acted as predictors of suicidal ideation, while degree of impulsivity (β standardized = 0.13, p = 0.229) and educational level (standardized β = - 0.16, p = 0.108) did not give a significant contribution.

CONCLUSION

According to our results, more severe depression and mania symptoms, higher level of insight and a history of suicide attempt indicate the occurrence of suicidal ideation in BD.

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.

Altered Levels of Plasma Inflammatory Cytokines and White Matter Integrity in Bipolar Disorder Patients With Suicide Attempts

OBJECTIVE

Bipolar disorder (BD) has a higher lifetime rate of suicide attempts (SA) than other psychiatric disorders. Furthermore, BD patients with SA (BD + S) are prone to a worse quality of life. However, the pathophysiology of BD + S is poorly understood. To further reveal the potential mechanisms of BD + S, abnormalities in peripheral plasma inflammatory cytokines and brain white matter (WM) in BD + S, as well as the correlation between them are investigated.

METHODS

We tested the levels of TNF-α, IL-1β, and IL-6 in peripheral plasma and collected the diffusion tensor imaging (DTI) data from 14 BD + S, 24 BD patients without SA (BD-S), and 26 healthy controls (HCs). The three groups were matched by age and gender. The levels of TNF-α, IL-1β, and IL-6 were detected by Luminex multifactor detection technology, and the fractional anisotropy (FA) values were employed to depict the alterations of WM. Partial correlation analyses were conducted to detect correlations between levels of TNF-α, IL-1β, and IL-6 and changes of WM, and the relationships between severity of clinical symptoms, including scores of HAMD-17 and YMRS, and cytokine levels or FA values in all groups.

RESULTS

For plasma inflammatory cytokines, there was no significant difference in their levels except for IL-6 among the three groups. Post-hoc analyses revealed that increased IL-6 level was only detected in BD + S (p < 0.05, Bonferroni correction). For DTI, BD + S showed specifically decreased FA in the bilateral middle cerebellar peduncle and the left superior corona radiata compared to BD-S and HCs (p < 0.05, Bonferroni correction). Additionally, both BD + S and BD-S groups revealed decreased FA in the bilateral body and genu of corpus callosum (CC) compared to HCs (p < 0.05, Bonferroni correction). No significant correlation between plasma inflammatory cytokines and WM integrity was found. In the BD + S group, we found negative correlation between the scores of YMRS and FA values of the left middle cerebellar peduncle (r = -0.74, p = 0.035).

CONCLUSION

The inflammation and impaired WM integrity may provide a scientific basis to understand the potential mechanisms of BD + S.

Sex Differences in Bipolar Disorders: Impact on Psychopathological Features and Treatment Response

INTRODUCTION

Sex differences were demonstrated in bipolar disorders (BD) concerning epidemiological, clinical, and psychopathological characteristics, but consensus is lacking. Moreover, data concerning the influence of sex on treatment response in BD is contrasting. The present cross-sectional study aimed to analyze sex differences in a population of BD subjects, with specific focus on psychopathological features and treatment response.

MATERIALS AND METHODS

Subjects diagnosed with BD according to the Diagnostic and Statistical Manual of Mental Disorders, 5th version (DSM-5) were recruited. Socio-demographic and clinical characteristics were collected. The Hamilton Rating Scale for Depression, the Mania Rating Scale (MRS), the brief version of the Temperament Evaluation of Memphis, Pisa and San Diego-Münster version (briefTEMPS-M), and the Barratt Impulsiveness Scale-11 items (BIS-11) were used for psychopathological assessment. Treatment response was appraised with the Alda Scale. We performed bivariate analyses to compare socio-demographic, clinical, and psychopathological characteristics between men and women (p < 0.05). A logistic regression was run to analyze features that were significantly associated with female sex.

RESULTS

Among the recruited 219 BD subjects, 119 (54.3%) were females. Women had a lower scholarity (p = 0.015) and were less frequently employed (p = 0.001). As for psychopathological features, a higher MRS total score (p < 0.001) was detected among women, as well as higher BIS-11 total score (p = 0.040), and briefTEMPS-M score for anxious temperament (p = 0.006). Men showed higher prevalence of DSM-5 mixed features (p = 0.025), particularly during a depressive episode (p = 0.014). Women reported longer duration of untreated illness (DUI) (p < 0.001). There were no sex differences in the Alda Scale total score when considering the whole sample, but this was significantly higher among men (p = 0.030) when evaluating subjects treated with anticonvulsants. At the logistic regression, female sex was positively associated with longer DUI (p < 0.001; OR 1.106, 95% CI 1.050-1.165) and higher MRS total score (p < 0.001; OR 1.085, 95% CI 1.044-1.128) and negatively associated with employment (p = 0.003; OR 0.359, 95% CI 0.185-0.698) and DSM-5 mixed features (p = 0.006; OR 0.391, 95% CI 0.200-0.762).

CONCLUSIONS

The clinical presentation of BD may differ depending on sex. The severity of BD should not be neglected among women, who may also display worse treatment response to anticonvulsants.

Symptoms of mania and anxiety do not contribute to suicidal ideation or behavior in the presence of bipolar depression

Bipolar disorder is typified by episodes of manic/hypomanic and depressive symptoms, either distinctly or concurrently as mixed symptoms. While depressive symptoms are the major driver of risk, it is unclear whether specific combinations of manic and anxiety symptoms contribute differentially to suicidal ideation and behavior in individuals with bipolar disorder during a depressive state. This study uses a quantitative application of Rothman's theoretical framework of causation, or 'causal pies' model. Data were obtained from the National Network of Depression Centers Mood Outcomes Program for 1028 visits from 626 individuals with bipolar disorder with current moderate-to-severe depressive symptoms, operationalized as a Patient Health Questionnaire-8 (PHQ-8) score ≥10. Mania symptoms were captured using the Altman Self-Rating Mania scale (ASRM) and anxiety symptoms were captured using the Generalized Anxiety Disorder-7 scale (GAD-7). The outcome of suicidal ideation or behavior was captured using the Columbia Suicide Severity Rating Scale (C-SSRS). In this cohort of individuals with bipolar disorder and at least moderate depressive symptoms, we found no increased risk of suicidal ideation or behavior attributable to manic and anxiety symptom clusters in individuals with bipolar disorder during depressive state. A small amount (4%) of risk was attributable to having severe depressive symptoms. These findings, however, may be influenced by limitations in sample size and measurement instruments. Future studies would benefit from larger samples and more rigorous assessments, including clinician-rated measures.

Alterations in resting-state global brain connectivity in bipolar I disorder patients with prior suicide attempt

BACKGROUND

Bipolar I disorder (BD-I) is associated with a high risk of suicide attempt; however, the neural circuit dysfunction that confers suicidal vulnerability in individuals with this disorder remains largely unknown. Resting-state functional magnetic resonance imaging (rs-fMRI) allows non-invasive mapping of brain functional connectivity. The current study used an unbiased voxel-based graph theory analysis of rs-fMRI to investigate the intrinsic brain networks of BD-I patients with and without suicide attempt.

METHODS

A total of 30 BD-I patients with suicide attempt (attempter group), 82 patients without suicide attempt (non-attempter group), and 67 healthy controls underwent rs-fMRI scan, and then global brain connectivity (GBC) was computed as the sum of connections of each voxel with all other gray matter voxels in the brain.

RESULTS

Compared with the non-attempter group, we found regional differences in GBC values in emotion-encoding circuits, including the left superior temporal gyrus, bilateral insula/rolandic operculum, and right precuneus (PCu)/cuneus in the bipolar disorder (BD) attempter group, and these disrupted hub-like regions displayed fair to good power in distinguishing attempters from non-attempters among BD-I patients. GBC values of the right PCu/cuneus were positively correlated with illness duration and education in the attempter group.

CONCLUSIONS

Our results indicate that abnormal connectivity patterns in emotion-encoding circuits are associated with the increasing risk of vulnerability to suicide attempt in BD patients, and global dysconnectivity across these emotion-encoding circuits might serve as potential biomarkers for classification of suicide attempt in BD patients.

Aggression, Impulsivity and Suicidal Behavior in Depressive Disorders: A Comparison Study between New York City (US), Madrid (Spain) and Florence (Italy)

The association of aggression and impulsivity with suicidal behavior (SB) in depression may vary across countries. This study aimed (i) to compare aggression and impulsivity levels, measured with the Brown-Goodwin Scale (BGS) and the Barratt Impulsivity Scale (BIS), respectively, between New York City (NYC) (US), Madrid (Spain) and Florence (Italy) (ANOVA); and (ii) to investigate between-site differences in the association of aggression and impulsivity with previous SB (binary logistic regression). Aggression scores were higher in NYC, followed by Florence and Madrid. Impulsivity levels were higher in Florence than in Madrid or NYC. Aggression and impulsivity scores were higher in suicide attempters than in non-attempters in NYC and in Madrid. SB was associated with aggression in NYC (OR 1.12, 95% CI 1.07–1.16; p < 0.001) and in Florence (OR 1.11, 95% CI 1.01–1.22; p = 0.032). Impulsivity was linked with SB in NYC (OR 1.01, 95% CI 1.00–1.02; p < 0.001) and in Madrid (OR 1.03, 95% CI 1.02–1.05; p < 0.001). The higher suicide rates in NYC, compared to Madrid or Florence, may be, in part, explained by these cross-cultural differences in the contribution of aggression-impulsivity to SB, which should be considered by future research on SB prevention.

Altered behaviour, dopamine and norepinephrine regulation in stressed mice heterozygous in TPH2 gene

Gene-environment interaction (GxE) determines the vulnerability of an individual to a spectrum of stress-related neuropsychiatric disorders. Increased impulsivity, excessive aggression, and other behavioural characteristics are associated with variants within the tryptophan hydroxylase-2 (Tph2) gene, a key enzyme in brain serotonin synthesis. This phenotype is recapitulated in naïve mice with complete, but not with partial Tph2 inactivation. Tph2 haploinsufficiency in animals reflects allelic variation of Tph2 facilitating the elucidation of respective GxE mechanisms. Recently, we showed excessive aggression and altered serotonin brain metabolism in heterozygous Tph2-deficient male mice (Tph2^+/-) after predator stress exposure. Here, we sought to extend these studies by investigating aggressive and anxiety-like behaviours, sociability, and the brain metabolism of dopamine and noradrenaline. Separately, Tph2^+/- mice were examined for exploration activity in a novel environment and for the potentiation of helplessness in the modified swim test (ModFST). Predation stress procedure increased measures of aggression, dominancy, and suppressed sociability in Tph2^+/- mice, which was the opposite of that observed in control mice. Anxiety-like behaviour was unaltered in the mutants and elevated in controls. Tph2^+/- mice exposed to environmental novelty or to the ModFST exhibited increased novelty exploration and no increase in floating behaviour compared to controls, which is suggestive of resilience to stress and despair. High-performance liquid chromatography (HPLC) revealed significant genotype-dependent differences in the metabolism of dopamine, and norepinephrine within the brain tissue. In conclusion, environmentally challenged Tph2^+/- mice exhibit behaviours that resemble the behaviour of non-stressed null mutants, which reveals how GxE interaction studies can unmask latent genetically determined predispositions.

Temporal dynamics alterations of spontaneous neuronal activity in anterior cingulate cortex predict suicidal risk in bipolar II patients

Bipolar disorder type II (BD-II) is linked to an increased suicidal risk. Since a prior suicide attempt (SA) is the single most important risk factor for sequent suicide, the elucidation of involved neural substrates is critical for its prevention. Therefore, we examined the spontaneous brain activity and its temporal variabilities in suicide attempters with bipolar II during a major depressive episode. In this cross-sectional study, 101 patients with BD-II, including 44 suicidal attempters and 57 non-attempters, and 60 non-psychiatric controls underwent a resting-state functional magnetic resonance imaging (fMRI). Participants were assessed with Hamilton Rating Scale for Depression (HAMD) and Nurses^, Global Assessment of Suicide Risk (NGASR). The dynamics of low-frequency fluctuation (dALFF) was measured using sliding-window analysis and its correlation with suicidal risk was conducted using Pearson correlation. Compared to non-attempters, suicidal attempters showed an increase in brain activity and temporal dynamics in the anterior cingulate cortex (ACC). In addition, the temporal variabilities of ACC activity positively correlated with suicidal risk (R = 0.45, p = 0.004), while static ACC activity failed to (R = 0.08, p > 0.05). Our findings showed that an aberrant static ALFF and temporal variability could affect suicidal behavior in BD-II patients. However, temporal variability of neuronal activity was more sensitive than static amplitude in reflecting diathesis for suicide in BD-II. Dynamics of brain activity could be considered in developing neuromarkers for suicide prevention.

The effects of childhood emotional maltreatment and alexithymia on depressive and manic symptoms and suicidal ideation in females with bipolar disorder: emotion dysregulation as a mediator

OBJECTIVES

The relations of childhood emotional maltreatment and alexithymia to the clinical course of bipolar disorder (BD) have been widely recognised. Difficulties in regulating emotions may explain these relationships. The current study evaluated the effects of childhood emotional maltreatment and alexithymia on depressive and manic symptoms as well as suicidal ideation in female patients with BD. Emotion dysregulation was evaluated as a mediating factor.

METHODS

Three hundred hospitalised female patients with a diagnosis of BD provided information regarding their history of childhood emotional maltreatment, alexithymia, difficulties in emotion regulation, depressive and manic symptoms, and suicidal ideation. A series of structural equation models (SEMs) were calculated to assess the associations between these variables.

RESULTS

Childhood emotional abuse and difficulty in identifying feelings were indirectly associated with depressive and manic symptoms as well as suicidal ideation. This association was mediated by emotion dysregulation. This association remained significant after depressive and manic symptoms were controlled in the model.

CONCLUSIONS

This study indicates that patients with BD who experienced emotional abuse during childhood and have difficulties identifying emotions report greater emotion dysregulation. These individuals, in turn, are more likely to experience more severe depressive and manic symptoms as well as suicidal ideation.Key pointsChildhood emotional maltreatment and emotional and clinical factors in bipolar disorder were assessed.Childhood emotional abuse indirectly affected clinical factors via emotion dysregulation.Difficulty in identifying feelings was linked to clinical factors via emotional dysregulation.Emotional dysregulation affected the links of childhood emotional maltreatment and difficulty in identifying feelings on suicidal ideation after controlling for clinical symptoms.Emotional dysregulation dimensions of impulse, strategies, and goals emerge in relation to suicidal ideation.

Clustering suicidal phenotypes and genetic associations with brain-derived neurotrophic factor in patients with substance use disorders

Suicide attempts (SA), especially recurrent SA or serious SA, are common in substance use disorders (SUD). However, the genetic component of SA in SUD samples remains unclear. Brain-derived neurotrophic factor (BDNF) alleles and levels have been repeatedly involved in stress-related psychopathology. This investigation uses a within-cases study of BDNF and associated factors in three suicidal phenotypes ('any', 'recurrent', and 'serious') of outpatients seeking treatment for opiate and/or cocaine use disorder. Phenotypic characterization was ascertained using a semi-structured interview. After thorough quality control, 98 SNPs of BDNF and associated factors (the BDNF pathway) were extracted from whole-genome data, leaving 411 patients of Caucasian ancestry, who had reliable data regarding their SA history. Binary and multinomial regression with the three suicidal phenotypes were further performed to adjust for possible confounders, along with hierarchical clustering and compared to controls (N = 2504). Bayesian analyses were conducted to detect pleiotropy across the suicidal phenotypes. Among 154 (37%) ever suicide attempters, 104 (68%) reported at least one serious SA and 96 (57%) two SA or more. The median number of non-tobacco SUDs was three. The BDNF gene remained associated with lifetime SA in SNP-based (rs7934165, rs10835210) and gene-based tests within the clinical sample. rs10835210 clustered with serious SA. Bayesian analysis identified genetic correlation between 'any' and 'serious' SA regarding rs7934165. Despite limitations, 'serious' SA was shown to share both clinical and genetic risk factors of SA-not otherwise specified, suggesting a shared BDNF-related pathophysiology of SA in this population with multiple SUDs.

Suicide in Psychiatric Inpatients- A Case-Control Study

Objective: Psychiatric inpatients constitute a population at considerably increased risk for suicide. Identifying those at imminent risk is still a challenging task for hospital staff. This retrospective case-control study focused on clinical risk factors related to the course of the hospital stay. Method: Inpatient suicide cases were identified by linking the Tyrol Suicide Register with the registers of three psychiatric hospitals in the state. Control subjects were patients who had also been hospitalized in the respective psychiatric unit but had not died by suicide. Matching variables included sex, age, hospital, diagnosis, and admission date. The study period comprised 7 years. Data were analyzed by the appropriate two-sample tests and by logistic regression. Results: A total of 30 inpatient suicide cases and 54 control patients were included. A number of factors differentiated cases from controls; after correction for multiple testing, the following retained significance: history of aborted suicide, history of attempted suicide, history of any suicidal behavior/threats, suicidal ideation continuing during hospitalization, no development of prospective plans, no improvement of mood during the hospital stay, and leaving ward without giving notice. Logistic regression identified the latter three variables and history of attempted suicide as highly significant predictors of inpatient suicide. Conclusions: Preventive measures during hospitalization include thorough assessment of suicidal features, an emphasis on the development of future perspectives, and a review of hospital regulations for patients who want to leave the ward.

Discriminating Suicide Attempters and Predicting Suicide Risk Using Altered Frontolimbic Resting-State Functional Connectivity in Patients With Bipolar II Disorder

Bipolar II disorder (BD-II) major depression episode is highly associated with suicidality, and objective neural biomarkers could be key elements to assist in early prevention and intervention. This study aimed to integrate altered brain functionality in the frontolimbic system and machine learning techniques to classify suicidal BD-II patients and predict suicidality risk at the individual level. A cohort of 169 participants were enrolled, including 43 BD-II depression patients with at least one suicide attempt during a current depressive episode (SA), 62 BD-II depression patients without a history of attempted suicide (NSA), and 64 demographically matched healthy controls (HCs). We compared resting-state functional connectivity (rsFC) in the frontolimbic system among the three groups and explored the correlation between abnormal rsFCs and the level of suicide risk (assessed using the Nurses' Global Assessment of Suicide Risk, NGASR) in SA patients. Then, we applied support vector machines (SVMs) to classify SA vs. NSA in BD-II patients and predicted the risk of suicidality. SA patients showed significantly decreased frontolimbic rsFCs compared to NSA patients. The left amygdala-right middle frontal gyrus (orbital part) rsFC was negatively correlated with NGASR in the SA group, but not the severity of depressive or anxiety symptoms. Using frontolimbic rsFCs as features, the SVMs obtained an overall 84% classification accuracy in distinguishing SA and NSA. A significant correlation was observed between the SVMs-predicted NGASR and clinical assessed NGASR (r = 0.51, p = 0.001). Our results demonstrated that decreased rsFCs in the frontolimbic system might be critical objective features of suicidality in BD-II patients, and could be useful for objective prediction of suicidality risk in individuals.