The neurobiology of suicide

Increased levels of neurofilament light chain in suicide attempters' serum

Background

A specific biological vulnerability underlies suicidal behavior. Recent findings have suggested a possible role of inflammation and neuroaxonal injury. However, the relationship between inflammation and clinical symptoms in this disorder is still unclear. The objective of this study is applying novel blood markers of neuroaxonal integrity such as neurofilament light chain (NfL) and comparing the results with the healthy control subjects.

Methods

In this cross-sectional study patients with suicide attempts were evaluated. The serum concentration of NfL on admission was measured by enzyme-linked immunosorbent assays.

Results

A total of 50 patients with a suicide attempts and 35 healthy controls were included in the study. The levels of NfL in attempted suicide patients were significantly higher in comparison with healthy controls (40.52 ± 33.54 vs 13.73 ± 5.11, P < 0.001). A significant association between serum levels of NfL and risk factors for suicide was not found.

Conclusion

These findings indicate that axonal damage may be an underlying neuropathological component of suicide attempt patients, although no correlation was observed with clinical features. This line of work could lead to new horizons in understanding the neurobiology of suicidal attempts and the development of better management strategies for these patients.

Comparisons of Serum Interleukin-8 Levels in Major Depressive Patients With Drug-Free Versus SSRIs Versus Healthy Controls

OBJECTIVE

The interleukin-8 (IL-8) has been reported to play an important role in depression, which might be modulated by the selective serotonin reuptake inhibitors (SSRIs). Thus, the aim of this study was to investigate serum IL-8 levels, depressive symptom, and their associations in drug-free MDD patients, MDD patients with SSRIs, and healthy controls (HCs).

METHODS

Fifty-seven drug-free MDD patients (male/female = 35/22, mean age: 39.24 years), 30 MDD patients with SSRIs (male/female = 11/19, mean age: 39.73 years), and 101 HCs (male/female = 52/49, mean age: 37.38 years) were recruited in this cross-sectional study. Serum IL-8 levels and depressive symptom were assessed using the Flow Cytometer and Hamilton Depression Scale (HAMD). The analysis of variance was used for the comparison between groups. The relationship between serum log₁₀ IL-8 levels and HAMD score was analyzed by Pearson correlation.

RESULTS

Serum log₁₀IL-8 levels were lower in all patients than HCs after controlling for covariates (F = 4.86, p = 0.03). There was significant difference in serum Log₁₀IL-8 levels among three groups after controlling for covariates (F = 14.63, p < 0.001). Serum Log₁₀IL-8 levels in drug-free patients were lower compared to HCs (F = 19.38, p < 0.001) or patients with SSRIs (F = 21.89, p < 0.001) after controlling for covariates. However, there was not difference in serum log₁₀IL-8 levels between patients with SSRIs and HCs after controlling for covariates. Moreover, serum Log₁₀IL-8 levels were negatively correlated with HAMD score in all patients (r = -0.37, p = 0.02). Also, serum Log₁₀IL-8 levels were negatively correlated with HAMD score in drug-free patients (r = -0.74, p = 0.01), but not in patients with SSRIs.

CONCLUSION

Our data supported that the decline in serum IL-8 levels was association with depression. Moreover, the SSRIs might modulate increased serum IL-8 levels of depression.

Effects of vitamin D-related gene polymorphisms on attempted suicide

OBJECTIVE

Emerging evidence suggests that vitamin D might protect from attempted suicide. The study aimed to investigate the associations between single-nucleotide polymorphisms (SNPs) related to vitamin D levels identified in a large genome-wide association study and attempted suicide in rural China.

METHODS

This 1:1 matched case-control study included altogether 510 suicide attempters and 510 community controls. Genotypes of four target SNPs (DHCR7-rs12785878, CYP2R1-rs10741657, GC-rs2282679, and CYP24A1-rs6013897) were determined, and a genetic risk score (GRS) was constructed to evaluate the combined effect of them. Demographic and psychological information was acquired through face-to-face interviews.

RESULTS

The A allele of CYP24A1-rs6013897 was significantly associated with attempted suicide (OR = 1.27, 95% CI, 1.03-1.58, P = 0.029), even after adjusting for demographic and psychological confounders (adjusted OR = 1.53, 95% CI, 1.01-2.30, P = 0.043). The GRS analyses revealed a significantly higher risk of attempted suicide with a greater number of low vitamin D alleles (adjusted OR = 1.33, 95% CI, 1.13-1.58, P < 0.001). Subgroup analyses stratified by sex indicated that the genetic associations were only significant among males with adjusted ORs of 3.77 (95% CI, 1.56-9.10) for the A allele of rs6013897 and 2.04 (95% CI, 1.32-3.17) for GRS.

CONCLUSIONS

Our findings identity CYP24A1-rs6013897 as a potential biomarker for attempted suicide and indicate that a genetic predisposition to lower vitamin D levels may contribute to attempted suicide. It suggests the possibility that vitamin D may have the preventive potential for attempted suicide.

Telomeres are shorter and associated with number of suicide attempts in affective disorders

BACKGROUND

Shorter telomere length is a putative biomarker of accelerated aging and has been associated with affective disorders and mortality. Psychological factors and behaviors associated with telomere shortening are yet to be clarified. Here, we investigate the association between history of suicide attempts and telomere length in patients with affective disorders.

METHODS

Leucocyte telomere length was determined by quantitative real-time Polymerase Chain Reaction (qPCR) in patients with affective disorders (n = 248) including bipolar disorders type I (n = 159), type II (n = 67), major depressive disorder (n = 22), and healthy controls (n = 401). Diagnosis, duration of illness, and age at onset were assessed using the Structural Clinical Interview for DSM-IV (SCID-I). Number of lifetime suicide attempts were based on self-reports. Effect size was calculated using Cohen's d.

RESULTS

Telomere length was reduced in patients with affective disorders relative to healthy controls (d = 0.18, F = 5.26, p = 0.02). Among patients, a higher number of suicide attempts was associated with shorter telomere length (β = -0.24, t = -3.83, CI = -0.44 to -0.14, p < 0.001), also when controlling for duration of illness and age at onset (β = -.23, CI = -.42 to -.12, p = 0.001). Multiple suicide attempts were associated with telomere length reduction comparable to eight years lifespan, adjusted for demographic and clinical characteristics.

CONCLUSIONS

While longitudinal data are needed to clarify the temporal course, previous suicide attempts and related distress may accelerate telomere shortening and aging in patients with affective disorders.

Functional gastrointestinal disorders as predictors of suicidal ideation. An observational study

BACKGROUND/OBJECTIVES

Suicidal ideation (SI), a symptom of depression, is known to be associated with irritable bowel syndrome (IBS) but is not known to be associated with other functional gastrointestinal disorders (FGIDs). However, the source of this association is discussed. It could be related to a possible abnormal biochemical pathway implicating neurotransmitters common to both disorders like serotonin or pain and an ill-being associated with a chronic disorder of unknown etiology. The present study aims to search for the FGIDs associated with suicidal ideation.

DESIGN

Observational study.

METHODS

A total of 1469 patients with FGIDs (71% of women) were included in the present study. They filled the Rome III questionnaire, Beck depression inventory, and state and trait anxiety questionnaires. Data were analyzed using analysis of variance with Bonferroni correction and logistic regression analysis.

RESULTS

Suicidal ideation was reported by 15% of patients, associated with increased scales of depression (P < 0.001), state (P = 0.006), and trait anxiety (P = 0.021). Clinically, these patients reported a higher prevalence of IBS-diarrhea subtype (P = 0.045), fecal incontinence (P = 0.020), soiling (P = 0.016), and difficult defecation (P = 0.005), and higher perceived severity for constipation, diarrhea, bloating, and abdominal pain (P < 0.001 for all scales).

CONCLUSIONS

This study shows that only functional bowel and functional anorectal disorders are associated with suicidal ideation. This result must be taken into account in the management of these patients.

Web-Based Eye Movement Desensitization and Reprocessing for Adults With Suicidal Ideation: Protocol for a Randomized Controlled Trial

BACKGROUND

Adversity and traumatic experiences increase the likelihood of suicidal thoughts and behaviors. Eye Movement Desensitization and Reprocessing (EMDR) is an evidence-based, trauma-focused psychotherapy that desensitizes painful memories, so that reminders in the present no longer provoke overwhelming emotional responses. Preliminary evidence suggests that EMDR can be used as an acute intervention in suicidal patients, including those with major depressive disorder. In addition, because of social distancing restrictions during the COVID-19 pandemic, clinicians have been using EMDR on the web and, in the absence of formal evaluations of web-based EMDR, informal reports indicate good results.

OBJECTIVE

The primary aim of this randomized controlled trial is to investigate whether remotely delivered EMDR (targeting experiences associated with suicidal thinking) reduces suicidal thoughts. Secondary aims include examining the impact of remotely delivered EMDR on symptoms of depression, anxiety, posttraumatic stress, emotional dysregulation, and dissociation. We will also report on adverse events in the EMDR group to explore whether targeting suicidal ideation with EMDR is safe. Finally, we will compare dropout rates between the treatment groups.

METHODS

In this randomized controlled trial, 80 adults who express suicidal ideation and meet the study criteria will receive either 12 sessions of twice weekly EMDR plus treatment as usual or treatment as usual alone. EMDR sessions will focus on the most distressing and intrusive memories associated with suicidal ideation. Data for primary and secondary objectives will be collected at baseline, 2 months, and 4 months after enrollment. A subsequent longer-term analysis, beyond the scope of this protocol, will examine differences between the groups with respect to the number of posttreatment emergency room visits, hospitalizations, and overall health care use in the year before and after therapy.

RESULTS

The protocol was approved by the University of Alberta Research Health Ethics Board (protocol ID Pro00090989). Funding for this study was provided by the Mental Health Foundation (grant RES0048906). Recruitment started in May 2021, with a projected completion date of March 2023.

CONCLUSIONS

The results of this trial will contribute to knowledge on whether web-based delivery of EMDR is a safe and effective treatment for reducing suicidal ideation and potentially reducing the incidence of suicide attempts in this patient population.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04181047; https://clinicaltrials.gov/ct2/show/NCT04181047.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/30711.

Obsessive Thought, Compulsive Behavior, and Their Associations With Suicide Ideation and Attempts and Major Depressive Disorder: A Nationwide Community Sample of Korean Adults

ABSTRACT

In this study, we defined obsessive thoughts (OT) as bothersome, unpleasant thoughts about oneself that keep entering the mind against one's will, and compulsive behavior (CB) as behavior that a person repeats against his or her wishes. The study included 12,532 adults selected randomly through a one-person-per-household method. Each subject selected underwent a face-to-face interview using the Korean version of the Composite International Diagnostic Interview with a questionnaire that examines lifetime suicide attempts (LSAs). Among the participants, 341 (2.74%) had OT and 639 (5.14%) had CB. The highest LSA rate was in subjects with both OT and CB, followed by those with either OT or CB; subjects with neither OT nor CB had the lowest LSA rate. In a multivariate logistic regression analysis of OT and CB, OT, ordering, and rituals of repeating words were significantly associated with LSAs. In subjects with OT and CB, those with MDD had a significantly higher risk of LSAs compared with those without, and MDD with both OT and CB showed odds of approximately 27-fold (adjusted odds ratio, 27.24; 13.29-55.82; p < 0.0001) compared with those without MDD, OT, or CB. OT and CB were associated with increased risk of LSAs, and comorbid MDD further increased LSAs.

Genetic testing for suicide risk assessment: Theoretical premises, research challenges and ethical concerns

We explore ethical premises and practical implications of using genetic testing to predict suicide risk. Twin studies indicate heritable components of suicide risk, intertwined with the heritability of mental disorders, and possibly other traits. Current genetics research has abandoned searching for single gene Mendelian determinants, in favour of complex probabilistic epigenetic models. Genome-Wide Association Studies (GWAS) might identify thousands of single nucleotide polymorphisms (SNPs), each contributing very little to the variance associated with behavioral phenotypes. However, suicide is a behavioral outcome rather than a phenotype, with so many different causal aetiologies, that it is impossible to predict the behaviors of individuals. We analyse practical and ethical issues that would arise if future research were to identify genetic information that will accurately predict suicide. Applying ACCE guidelines that specify when genetic tests should and should not be used, we examine the Analytic Validity, Clinical Validity, Clinical Utility and Ethical, Legal, and Social Implications. Low sensitivity and specificity for predicting suicide diminish potential advantages and exacerbate risks. Key considerations include the likelihood that testing will result in effective preventive interventions, which are not currently available, and unreliable positive results increasing hopelessness, stigma, and psychosocial risks. If the unregulated direct-to-consumer genetic testing services include suicide risk assessments, their use risks negative impacts. In the future, if genetic testing could accurately identify suicide risk in individuals, its use would be contraindicated if we cannot provide effective preventive interventions and mitigate the negative impacts of informing people about their risk level.

Exposure to ambient air pollution during childhood and subsequent risk of self-harm: A national cohort study

A growing body of evidence indicates that exposure to air pollution not only impacts on physical health but is also linked with a deterioration in mental health. We conducted the first study to investigate exposure to ambient particulate matter with an aerodynamic diameter of less than 2.5 μm (PM_2.5) and nitrogen dioxide (NO₂) during childhood and subsequent self-harm risk. The study cohort included persons born in Denmark between January 1, 1979 and December 31, 2006 (N = 1,424,670), with information on daily exposures to PM_2.5 and NO₂ at residence from birth to 10th birthday. Follow-up began from 10th birthday until first hospital-presenting self-harm episode, death, or December 31, 2016, whichever came first. Incidence rate ratios estimated by Poisson regression models revealed a dose relationship between increasing PM_2.5 exposure and rising self-harm risk. Exposure to 17-19 μg/m³ of PM_2.5 on average per day from birth to 10th birthday was associated with a 1.45 fold (95% CI 1.37-1.53) subsequently elevated self-harm risk compared with a mean daily exposure of <13 μg/m³, whilst those exposed to 19 μg/m³ or above on average per day had a 1.59 times (1.45-1.75) elevated risk. Higher mean daily exposure to NO₂ during childhood was also linked with increased self-harm risk, but the dose-response relationship observed was less evident than for PM_2.5. Covariate adjustment attenuated the associations, but risk remained independently elevated. Although causality cannot be assumed, these novel findings indicate a potential etiological involvement of ambient air pollution in the development of mental ill health.

Influence Factors for Decision-Making Performance of Suicide Attempters and Suicide Ideators: The Roles of Somatic Markers and Explicit Knowledge

Impaired decision-making has been observed in suicide attempters during the Iowa Gambling Task (IGT). Decision-making performance is influenced by somatic markers and explicit knowledge, but it is still unclear of the influencing role on decision-making performance in suicidal individuals. We aimed to investigate whether there is a decision-making deficit in suicide attempters, suicide ideators, as well as the distinct roles of somatic markers and explicit knowledge wherein. Thirteen suicide attempters, 23 suicide ideators, and 19 healthy controls performed the IGT. Both somatic markers (by the skin conductance responses, SCRs) and explicit knowledge (by the subjective experience rating and a list of questions) were recorded. No significant differences were found among the three groups on IGT performance, explicit knowledge, and anticipatory SCRs. IGT Performance of suicide attempters was positively correlated with explicit knowledge index while behavior performance was positively associated with the SCRs in healthy controls. These results indicate that the suicide attempters seem to apply a compensatory strategy by mostly utilizing explicit knowledge to perform normally as healthy controls in the IGT.

A network meta-analysis of stress mediators in suicide behaviour

Stress homeostatic mediators are the most consistently anomalous biomarkers observed in suicide and may therefore point to a common 'core biology' of stress susceptibility, and suicidal behaviour. Previously reported meta-analyses have demonstrated aberrant levels of stress cortisol and inflammatory cytokines in suicide patients compared to controls, and significant associations between the stress regulator FK506-binding protein 51 (FKBP5) gene and suicidal behaviour. Although these independent studies were investigated as separate entities in suicide, stress mediators interact in a dynamic system, collectively giving rise to system changes physiologically, and ultimately psychologically and behaviourally. It is therefore important to study the dynamic network these stress mediators. Network meta-analysis allows for the simultaneous comparison of more than two biological mediators, and for comparisons to be made between mediators that have not been directly compared before, using previously reported, pooled meta data. Such network approaches may help study the complex biological phenomena of suicide and may provide better prediction of biological risk of suicidal states.

METHODS

This study aimed to establish the comparative relationships between key stress mediators in suicidal patients compared to non-suicidal controls using a random-effects network meta-analysis approach.. The key stress mediators included cortisol, six inflammatory markers (interleukin-6 (IL-6), interleukin-4 (IL-4), interleukin-2 (IL-2), tumour necrosis factor-a (TNF-α), interferon (IFN-y) and transforming growth factor β (TGF-β), and the FKBP5 single nucleotide polymorphism (SNP) allele. Data was derived from three previously published meta-analysis. The study population comprised of 1348 suicidal patients, defined as suicide attempters, completers, or patients with severe suicidal ideation, and 1750 non-suicidal controls, defined as healthy controls and psychiatric patients without suicidal ideation or previous attempts.

RESULTS

Pair-wise indirect effects of stress mediators in suicide compared to controls demonstrated that relative to the effect of the FKBP5 risk SNP allele on suicide risk, the magnitude of differences (suicide vs control) for the levels of IL-2 (SMD -0.72; 95% CI, -0.135 to -0.09 and IL-4 (SMD -0.71; 95% CI, -1.34 to -0.08) were significantly smaller (with 95% confidence intervals not crossing the null). The comparative relationships between stress mediators in suicidal behaviour demonstrates that the dynamic stress network relationship is dysregulated in suicide patients when compared to controls.

CONCLUSIONS

This model suggests that a genetic stress susceptibility with downstream abnormal cortisol stress axis functioning, together with anomalous interactions between the inflammatory system, may be one of the neurobiological correlates of suicide behaviour. This biological state may leave the individual physiologically susceptible and unable to cope with environmental stressors, which is consistent with the stress-diathesis hypothesis of suicide behaviour.

Resilience and vulnerability factors influence the cortisol awakening response in individuals vulnerable to suicide

Suicide is a global health issue. Dysregulated hypothalamic-pituitary-adrenal (HPA) axis activity, as measured by cortisol levels, has been identified as one potential risk factor. Evidence is emerging to suggest that different psychological factors may be associated with increased resilience and vulnerability in this context. The current study investigated whether trait resilience, social support, socially prescribed perfectionism, trait worry and trait impulsivity influenced the cortisol awakening response (CAR) over a 7-day study in individuals vulnerable to suicide. 142 participants with a history of suicidal attempt or ideation (suicide vulnerability group; n = 95) and with no suicide risk history (control group; n = 47) were recruited. Participants completed baseline questionnaires before commencing a 7-day study where they provided cortisol samples immediately upon waking, at 15 min, 30 min and 45 min on 7 consecutive days. Higher worry, socially prescribed perfectionism and impulsivity, lower resilience and social support were found in the suicide vulnerability group compared to the control group. Lower levels of resilience, higher levels of socially prescribed perfectionism, worry and impulsivity were associated with significantly lower total CAR. Suicide group membership was also found to have an indirect effect on total CAR via trait worry. The current findings show for the first time, that these well-known psychological risk factors for suicide are associated with smaller total cortisol awakening responses. Researchers ought to elucidate the precise causal mechanisms linking these traits, CAR and suicide risk in order to develop interventions to help build resilience in vulnerable populations.

The Modulatory Role of Serotonin on Human Impulsive Aggression

The hypothesis of chronically low brain serotonin levels as pathophysiologically linked to impulsive aggression has been around for several decades. Whereas the theory was initially based on indirect methods to probe serotonin function, our understanding of the neural mechanisms involved in impulsive aggression has progressed with recent advances in neuroimaging. The review integrates evidence based on data from several neuroimaging domains in humans. In vivo molecular neuroimaging findings demonstrate associations between impulsive aggression and high serotonin 1B and serotonin 4 receptor binding, high serotonin transporter levels, and low monoamine oxidase A levels, suggesting that low interstitial serotonin levels are a neurobiological risk factor for impulsive aggressive behavior. Imaging genetics suggests that serotonergic-related genetic polymorphisms associate with antisocial behavior, and some evidence indicates that the low-expressing monoamine oxidase A genotype specifically predisposes to impulsive aggression, which may be mediated by effects on corticolimbic function. Interventions that (presumably) alter serotonin levels have effects on brain activity within brain regions involved in impulsive aggression, notably the amygdala, dorsal striatum, anterior cingulate, insula, and prefrontal cortex. Based on these findings, we propose a model for the modulatory role of serotonin in impulsive aggression. Future studies should ensure that clinical features unique for impulsive aggression are appropriately assessed, and we propose investigations of knowledge gaps that can help confirm, refute, or modify our proposed model of impulsive aggression.

Thwarted belongingness predicts greater neural reactivity to a novel social exclusion image set: Evidence from the late positive potential

INTRODUCTION

Thwarted belongingness (TB) is among the most well-researched risk factors for suicidal ideation (SI). Yet, there is little research examining neural mechanisms underlying this construct. The present study used a novel social exclusion image set in concert with the late positive potential (LPP) to test the role of neural reactivity social exclusion in TB and SI.

METHODS

Participants (n = 243) were recruited based on elevated suicide risk and completed an emotional picture viewing task. The LPP was used to index neural reactivity to a novel set of social exclusion images and international affective picture system (IAPS) neutral, positive, and negative images.

RESULTS

Greater TB predicted a larger social exclusion ΔLPP (social exclusion LPP relative to neutral LPP) and social exclusion LPP even when accounting for SI, biological sex, age, negative affect, and perceived burdensomeness. Moreover, the social exclusion LPP was uniquely related to TB beyond the LPP to other images. Last, a larger social exclusion LPP predicted greater SI via elevations in TB.

CONCLUSION

Reactivity to social exclusion stimuli may play an important role in SI via elevated TB, but not perceived burdensomeness. Future research should further explore the neural mechanisms underlying other IPT constructs.

Antidepressant and anxiolytic compounds isolated from Salvia elegans interact with serotonergic drugs

Salvia elegans belongs to a genus plants with biological activities in central nervous system. In this work, the purpose was to evaluate the anxiolytic and antidepressant effects of fractions and compounds isolated from S. elegans and its interaction with serotoninergic drugs by using behavioral tests in mice. Fractions from aerial parts of S. elegans were obtained by column chromatography, SeF1, SeF2, SeF3, and SeF4. Each of them was administered to 25 mg/k in ICR mice subject to forced swimming test (FST), or elevated plus maze test (EPM), or open field test (OFT). The most active fractions were chemically separated until compounds, which were analyzed as anxiolytic or antidepressant and the coadministration of these treatments with 5-HT_1A and 5-HT₂ drugs was measured in the different biological tests. All fractions were anxiolytic and antidepressant, oleanolic acid (OA) was found in SeF2, and from SeF3, a mixture of terpenes was found; a GC-MS analysis confirmed the presence of two main compounds: rosifoliol and agaraspirol (TM, mixture of terpenes). TM (doses-response curve, 0.01, 0.1, 0.5, 1.0, and 2.0 mg/kg) and OA (5 mg/kg) were also evaluated demonstrating an antidepressant and anxiolytic effect, respectively. The combination of TM (0.5 mg/kg) with 8-OH (selective 5-HT_1A receptor agonist) induced an increment of antidepressant activity, while with the antagonist WAY-100635, the effect diminished. But with DOI (5-HT₁c/5-HT₂ receptor agonist), there was no change, and with KET (5-HT₂ receptor antagonist), the activity was increased. When OA is co-administered with 8-OH or with DOI, the anxiolytic activity of this terpene, diminished; but with the combination with antagonists, the effect of OA shows no change. TM and OA were antidepressant and anxiolytic, respectively, on mice exposed to different tests, and these are able to interact with serotoninergic drugs.

Suicidal thoughts, behaviors, and event-related potentials: A systematic review and meta-analysis

Suicidal thoughts and behaviors (STBs) are thought to result from, at least in part, abnormalities in various neural systems. Event-related potentials (ERPs) are a useful method for studying neural activity and can be leveraged to study neural deficits related to STBs; however, it is unknown how effective ERPs are at differentiating various STB groups. The present meta-analysis examined how well ERPs can differentiate (a) those with and without suicidal ideation, (b) those with and without suicide attempts, (c) those with different levels of suicide risk, and (d) differences between those with suicide attempts versus those with suicidal ideation only. This meta-analysis included 208 effect sizes from 2,517 participants from 27 studies. We used a random-effects meta-analysis using a restricted maximum likelihood estimator with robust variance estimation. We meta-analyzed ERP-STB combinations that had at least three effect sizes across two or more studies. A qualitative review found that for each ERP and STB combination, the literature is highly mixed. Our meta-analyses largely did not find significant relationships between STBs and ERPs. We also found that the literature is likely severely underpowered, with most studies only being sufficiently powered to detect unrealistically large effect sizes. Our results provided little-to-no support for a reliable relationship between the ERPs assessed and STBs. However, the current literature is severely underpowered, and there are many methodological weaknesses that must be resolved before making this determination. We recommend large-scale collaboration and improvements in measurement practices to combat the issues in this literature.

When Sick Brain and Hopelessness Meet: Some Aspects of Suicidality in the Neurological Patient

Neurological diseases expose individuals to a higher risk of suicidal ideation and suicidal behavior, including completed suicides and suicide attempts. They also represent a paradigmatic arena to study the etiopathogenic mechanisms underlying suicidality because they are emblematic of the heterogeneity and complexity of mutual interrelationships characterizing this issue. On the one hand, neurological diseases imply strictly biological impairments that are postulated to be the basis of vulnerability to suicide or result in the need for treatments for which a suicidal risk has been hypothesized. On the other hand, they question some subjective experiences of neurological patients, up to near existential positions. Often, in fact, they are accompanied by severe hopelessness. The latter may originate in, particularly for the most severe neurological diseases, the absence of curative treatments, unpredictable disease progression that leads to acute relapses or chronicity, a decrease in autonomy or selfidentity, progressive social isolation, a sense of becoming useless, and perception of feeling stigmatized. This may ultimately cause a slip into experiencing an absurd condition. At the confluence of neurobiology and hopelessness, frequent psychiatric comorbidities may play a primary role. To conclude, neurological patients require special attention from clinicians in form of openly verbalizing and exploring the suicidal thematic, inquiring about protective and risk factors, and promptly initiating both a psychopharmacological treatment and, where possible, psychological support.

Suicidal ideation among women who engage in sex work and have a history of drug use in Kazakhstan

Suicide rates in Kazakhstan rank fourth worldwide. Suicidal ideation is a strong predictor of death by suicide. Yet there is limited information about factors associated with suicidal ideation among women who engage in sex work (WESW) with a history of drug use. Guided by the Diathesis-Stress Theory of Suicide, this study examined the risk and protective factors associated with suicidal ideation among WESW in Kazakhstan. Data drew from the baseline assessments from a sample of four hundred women who participated in a cluster randomized control trial comparing a treatment arm which received a combination of HIV Risk Reduction (HIVRR) and microfinance intervention, and a control arm which received HIVRR alone. Multiple logistic regression models controlling for sociodemographic characteristics examined the effects of risk and protective factors on suicidal ideation. More than half of the participants (52.5%) reported suicidal ideation in the past seven days. Women with vulnerabilities such as child sexual abuse and harmful alcohol use and stressors such as stigma were more likely to think about suicide compared with those who did not. Keeping income from sex work was associated with a lower risk of suicidal ideation. HIV interventions targeting WESW and use drugs must include a mental health component to decrease the risk of suicidal ideation among this group. Women's ability to keep income from sex work suggests the potential to strengthen women's financial stability as a source of empowerment, which may in turn lessen the detrimental effects of childhood adversities and life stressors experienced by WESW.

Functional alterations of the suicidal brain: a coordinate-based meta-analysis of functional imaging studies

Altered brain activities in suicidal subjects have been reported in a number of neuroimaging studies. However, the activity aberrances were inconsistent in previous investigations. Thus, we aimed to address activity abnormalities in suicidal individuals. Databases were searched to perform a meta-analysis of whole-brain functional MRI studies of suicidal individuals through January 14, 2020. Meta-analyses were conducted using Seed-based d Mapping software. Based on a meta-analysis of 17 studies comprising 381 suicidal individuals and 642 controls, we mainly found that increased activity in the bilateral superior temporal gyrus, left middle temporal gyrus, and bilateral middle occipital gyrus, along with decreased activity in the right putamen and left insula, were detected in suicidal individuals compared with nonsuicidal subjects. To reduce methodological heterogeneity between the included studies, subanalyses of behavioral domains were conducted, and the right superior temporal gyrus was found to increase in all subanalyses of domains. In subanalyses of suicidal attempters and ideators, suicide attempters displayed hyperactivation in the bilateral superior temporal gyrus and left middle temporal gyrus and blunted responses in the left insula relative to controls. Suicidal ideators demonstrated elevated activation in the right middle occipital gyrus and reduced activity in the right putamen relative to controls. The bilateral superior temporal gyrus was the most robust finding, replicable in all data sets in the jackknife sensitive analysis. Moreover, increased activity in the right superior temporal gyrus, left middle temporal gyrus, and right middle occipital gyrus was found to be involved with higher suicide ideation scores. This study revealed several brain regions associated with suicidality. These findings may contribute to our understanding of the pathophysiology of suicide and have important implications for suicide prevention and interventions.

Detecting suicidal risk using MMPI-2 based on machine learning algorithm

Minnesota Multiphasic Personality Inventory-2 (MMPI-2) is a widely used tool for early detection of psychological maladjustment and assessing the level of adaptation for a large group in clinical settings, schools, and corporations. This study aims to evaluate the utility of MMPI-2 in assessing suicidal risk using the results of MMPI-2 and suicidal risk evaluation. A total of 7,824 datasets collected from college students were analyzed. The MMPI-2-Resturcutred Clinical Scales (MMPI-2-RF) and the response results for each question of the Mini International Neuropsychiatric Interview (MINI) suicidality module were used. For statistical analysis, random forest and K-Nearest Neighbors (KNN) techniques were used with suicidal ideation and suicide attempt as dependent variables and 50 MMPI-2 scale scores as predictors. On applying the random forest method to suicidal ideation and suicidal attempts, the accuracy was 92.9% and 95%, respectively, and the Area Under the Curves (AUCs) were 0.844 and 0.851, respectively. When the KNN method was applied, the accuracy was 91.6% and 94.7%, respectively, and the AUCs were 0.722 and 0.639, respectively. The study confirmed that machine learning using MMPI-2 for a large group provides reliable accuracy in classifying and predicting the subject's suicidal ideation and past suicidal attempts.

The Effect of Meteorological, Pollution, and Geographic Exposures on Death by Suicide: A Scoping Review

Suicide is a significant public health concern worldwide and in the United States. Despite the far-reaching impact of suicide, risk factors are still not well understood and efforts to accurately assess risk have fallen short. Current research has highlighted how potentially modifiable environmental exposures (i.e., meteorological, pollution, and geographic exposures) can affect suicide risk. A scoping review was conducted to evaluate the strength of the historical and current literature on the environment’s effect on suicide and suicide risk. Three databases (i.e., Medline, Embase, and PsychInfo) were reviewed to identify relevant studies and two authors independently reviewed studies considering pre-determined inclusion criteria. A total of 46 meteorological studies were included as well as 23 pollution studies and 12 geographic studies. Descriptive statistics, including counts, percentages, review of studies’ sample size (minimum, maximum, median, and interquartile range), were calculated using Excel and SAS 9.4. Overall, strong evidence supports that exposure to sunlight, temperature, air pollution, pesticides, and high altitude increases suicide risk, although effect sizes range from very small to small.

Suicide and Associations with Air Pollution and Ambient Temperature: A Systematic Review and Meta-Analysis

Given health threats of climate change, a comprehensive review of the impacts of ambient temperature and ar pollution on suicide is needed. We performed systematic literature review and meta-analysis of suicide risks associated with short-term exposure to ambient temperature and air pollution. Pubmed, Scopus, and Web of Science were searched for English-language publications using relevant keywords. Observational studies assessing risks of daily suicide and suicide attempts associated with temperature, particulate matter with aerodynamic diameter ≤10 μm (PM₁₀) and ≤2.5 mm (PM_2.5), ozone (O₃), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and carbon monoxide (CO) were included. Data extraction was independently performed in duplicate. Random-effect meta-analysis was applied to pool risk ratios (RRs) for increases in daily suicide per interquartile range (IQR) increase in exposure. Meta-regression analysis was applied to examine effect modification by income level based on gross national income (GNI) per capita, national suicide rates, and average level of exposure factors. In total 2274 articles were screened, with 18 studies meeting inclusion criteria for air pollution and 32 studies for temperature. RRs of suicide per 7.1 °C temperature was 1.09 (95% CI: 1.06, 1.13). RRs of suicide per IQR increase in PM_2.5, PM₁₀, and NO₂ were 1.02 (95% CI: 1.00, 1.05), 1.01 (95% CI: 1.00, 1.03), and 1.03 (95% CI: 1.00, 1.07). O₃, SO₂, and CO were not associated with suicide. RR of suicide was significantly higher in higher-income than lower-income countries (1.09, 95% CI: 1.07, 1.11 and 1.20, 95% CI: 1.14, 1.26 per 7.1 °C increased temperature, respectively). Suicide risks associated with air pollution did not significantly differ by income level, national suicide rates, or average exposure levels. Research gaps were found for interactions between air pollution and temperature on suicide risks.

Evaluating the association of adverse childhood experiences, mood and anxiety disorders, and suicidal ideation among behavioral health patients at a large federally qualified health center

Although numerous studies have examined the relationship between adverse childhood experiences (ACEs) and suicide, research is needed that studies the effects of specific ACEs, including subclasses of ACEs, independent of the effect of other ACEs. We explored the relationship between ACEs and suicidal ideation (SI) with special attention to patterns according to generation cohort (millennials: 22-37 years old, generation X: 38-53 years old, and baby boomers: 54-72 years old), and assessed the extent to which mood and anxiety disorders account for the relationship between ACEs and suicidal ideation. Patients in behavioral healthcare services of a large federally qualified health center (n = 4,392) were assessed at baseline on ACEs, SI, and mood and anxiety disorders. Logistic regression modeling was used to examine the data. Emotional neglect was the strongest predictor of SI among Millennials (OR = 1.59), Generation X (OR = 1.81), and Baby Boomers (OR = 1.88) after controlling for mood and anxiety disorders, race/ethnicity, and gender. Findings suggest ACEs predict an increased likelihood of having SI over and above the influence of mood and anxiety disorders, in models adjusted for gender and race/ethnicity. Across generations, the association with suicidal ideation was strongest for any child abuse and neglect, but not for household dysfunction. The observed association of ACEs with suicidal ideation suggests that ACEs should be considered as a risk factor and incorporated into screening assessments for suicidal ideation. Lastly, additional research on the association of ACEs and suicidality in individuals not actively being managed in behavioral healthcare settings is also warranted.

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.

Assessment of suicide attempt and death in bipolar affective disorder: a combined clinical and genetic approach

Bipolar disorder (BP) suicide death rates are 10-30 times greater than the general population, likely arising from environmental and genetic risk factors. Though suicidal behavior in BP has been investigated, studies have not addressed combined clinical and genetic factors specific to suicide death. To address this gap, a large, harmonized BP cohort was assessed to identify clinical risk factors for suicide death and attempt which then directed testing of underlying polygenic risks. 5901 individuals of European ancestry were assessed: 353 individuals with BP and 2498 without BP who died from suicide (BPS and NBPS, respectively) from a population-derived sample along with a volunteer-derived sample of 799 individuals with BP and a history of suicide attempt (BPSA), 824 individuals with BP and no prior attempts (BPNSA), and 1427 individuals without several common psychiatric illnesses per self-report (C). Clinical and subsequent directed genetic analyses utilized multivariable logistic models accounting for critical covariates and multiple testing. There was overrepresentation of diagnosis of PTSD (OR = 4.9, 95%CI: 3.1-7.6) in BPS versus BPSA, driven by female subjects. PRS assessments showed elevations in BPS including PTSD (OR = 1.3, 95%CI:1.1-1.5, versus C), female-derived ADHD (OR = 1.2, 95%CI:1.1-1.4, versus C), and male insomnia (OR = 1.4, 95%CI: 1.1-1.7, versus BPSA). The results provide support from genetic and clinical standpoints for dysregulated traumatic response particularly increasing risk of suicide death among individuals with BP of Northern European ancestry. Such findings may direct more aggressive treatment and prevention of trauma sequelae within at-risk bipolar individuals.

Neurocognitive Functioning in Adolescents at Risk for Suicidal Behaviors

Today, little is still known about the neurocognitive functioning of the individual at risk for suicide in a relevant developmental stage like adolescence. Thus, the main goal of the present work was to analyze the neurocognitive performance of adolescents at high risk for suicide. A total of 1509 adolescents from a stratified random cluster sampling were selected. Adolescents at risk for suicidal behaviors included 83 participants. A comparison group of 83 participants matched by age and gender was also randomly selected from the sample. The Paykel Suicide Scale (PSS) and the University of Pennsylvania Computerized Neurocognitive Battery for children (included 14 tasks assessing five neurobehavioral domains: executive functions, episodic memory, complex cognition, social cognition, and sensorimotor speed) were used. Adolescents at risk for suicide revealed statistically significant impairments across different neurocognitive domains including complex cognition, episodic memory and social cognition. No significant differences were found for Sensorimotor and Executive Function domains. Results found in the present study contribute relevant information about the nature of the neurocognitive impairments associated with suicide and add information in order to deeper comprehend the tentative etiology of suicide thoughts and attempts in adolescents with the aim to establish preventive treatments.

Improving Suicide Prevention Through Evidence-Based Strategies: A Systematic Review

OBJECTIVE

The authors sought to identify scalable evidence-based suicide prevention strategies.

METHODS

A search of PubMed and Google Scholar identified 20,234 articles published between September 2005 and December 2019, of which 97 were randomized controlled trials with suicidal behavior or ideation as primary outcomes or epidemiological studies of limiting access to lethal means, using educational approaches, and the impact of antidepressant treatment.

RESULTS

Training primary care physicians in depression recognition and treatment prevents suicide. Educating youths on depression and suicidal behavior, as well as active outreach to psychiatric patients after discharge or a suicidal crisis, prevents suicidal behavior. Meta-analyses find that antidepressants prevent suicide attempts, but individual randomized controlled trials appear to be underpowered. Ketamine reduces suicidal ideation in hours but is untested for suicidal behavior prevention. Cognitive-behavioral therapy and dialectical behavior therapy prevent suicidal behavior. Active screening for suicidal ideation or behavior is not proven to be better than just screening for depression. Education of gatekeepers about youth suicidal behavior lacks effectiveness. No randomized trials have been reported for gatekeeper training for prevention of adult suicidal behavior. Algorithm-driven electronic health record screening, Internet-based screening, and smartphone passive monitoring to identify high-risk patients are understudied. Means restriction, including of firearms, prevents suicide but is sporadically employed in the United States, even though firearms are used in half of all U.S. suicides.

CONCLUSIONS

Training general practitioners warrants wider implementation and testing in other nonpsychiatrist physician settings. Active follow-up of patients after discharge or a suicide-related crisis should be routine, and restricting firearm access by at-risk individuals warrants wider use. Combination approaches in health care systems show promise in reducing suicide in several countries, but evaluating the benefit attributable to each component is essential. Further suicide rate reduction requires evaluating newer approaches, such as electronic health record-derived algorithms, Internet-based screening methods, ketamine's potential benefit for preventing attempts, and passive monitoring of acute suicide risk change.

An exploratory magnetic resonance imaging study of suicidal ideation in individuals at clinical high-risk for psychosis

Suicide is a major cause of death in psychosis and associated with significant morbidity. Suicidal ideation (SI) is very common in those at clinical high-risk for psychosis (CHR) and predicts later suicide. Despite substantial work on the pathobiology of suicide in schizophrenia, little is known of its neurobiological underpinnings in the CHR or putatively prodromal state. Therefore, in this pilot study, we examined the neurobiology of SI in CHR individuals using structural MRI. Subjects were aged 14-30 and met criteria for the Attenuated Positive Symptom Psychosis-Risk Syndrome (APSS) delineated in the Structured Interview for Psychosis-Risk Syndromes (SIPS). Suicidality was assessed using the Columbia Suicide Severity Rating Scale (C-SSRS). Volumetric MRI scans were obtained on a 3T Phillips scanner. MRI data were available for 69 individuals (19 CHR without SI, 31 CHR with SI and 19 healthy control subjects). CHR individuals with SI had thicker middle temporal and right insular cortices than CHR individuals without SI and healthy control subjects. The location of these findings is consistent with neurobiological findings regarding suicide in syndromal psychosis. These findings underscore the potential for the use of brain imaging biomarkers of suicide risk in CHR individuals.

Distinguishing veterans with suicidal ideation from suicide attempt history: The role of emotion reactivity

INTRODUCTION

Growing evidence suggests emotion reactivity-sensitivity and intensity of emotional experience-may represent a diathesis for suicide risk. However, our understanding of its ability to differentiate risk for suicidal ideation (SI) from suicide attempt (SA) is limited.

METHOD

This study compares Veterans with SI (n = 81) to Veterans with SA (n = 177) history on factors relevant to emotion reactivity to determine which variable(s) best differentiate groups. Variables examined are multimodal: (a) self-report: childhood trauma, combat exposure; (b) clinician-assessed: non-suicidal self-injury (NSSI), structured diagnostic interview of psychopathology; and (c) psychophysiological: affect-modulated startle (AMS; proxy for amygdala reactivity and emotion reactivity) to unpleasant pictures was examined in a subset (n = 90).

RESULTS

SA history was independently predicted by NSSI history, MDD, PTSD, and SUD diagnosis. Childhood trauma and combat exposure did not differentiate groups. The composite risk index demonstrated good accuracy (AUC=0.71, sensitivity=0.90, specificity=0.49). Only AMS independently predicted SA history when added to the model and accuracy was improved (AUC=0.82, sensitivity=0.85, specificity=0.56).

CONCLUSION

NSSI history, MDD, PTSD, and SUD diagnosis may be salient risk factors for this population. However, emotion reactivity is a more parsimonious predictor of SA history among Veterans suggesting it is an important treatment target among Veterans with SI.

Relationship Between the Loudness Dependence of the Auditory Evoked Potential and the Severity of Suicidal Ideation in Patients with Major Depressive Disorder

Objective

The loudness dependence of the auditory evoked potential (LDAEP) is a reliable indicator that is inversely related to central serotonergic activity, and recent studies have suggested an association between LDAEP and suicidal ideation. This study investigated differences in LDAEP between patients with major depressive disorder and high suicidality and those with major depressive disorder and low suicidality compared to healthy controls.

Methods

This study included 67 participants: 23 patients with major depressive disorder with high suicidality (9 males, mean age 29.3 ± 15.7 years, total score of SSI-BECK ≥ 15), 22 patients with major depressive disorder with low suicidality (9 males, mean age 42.2 ± 14.4 years, total score of SSI-BECK ≤ 14), and 22 healthy controls (11 males, mean age 31.6 ± 8.7 years). Participants completed the following assessments: Patient Health Questionnaire-9, Beck Depression Inventory-II, Beck Scale for Suicidal ideation, State Anxiety Scale of the State-Trait Anxiety Inventory, Beck Anxiety Inventory, and LDAEP (measured at electrode Cz).

Results

There were no sex-related differences among groups (p = 0.821). The high-suicidality group exhibited significantly higher LDAEP compared to the low-suicidality group (0.82 ± 0.79 vs. 0.26 ± 0.36, p = 0.014). No significant differences were found between the control and high-suicidality (p = 0.281) or the control and low-suicidality groups (p = 0.236).

Conclusion

LDAEP was applied to demonstrate the association between serotonergic activity and suicidal ideation and suicide risk in major depression and may be a candidate of biological marker for preventing suicide in this study.

Dissecting pain processing in adolescents with Non-Suicidal Self Injury: Could suicide risk lurk among the electrodes?

Background

Although non‐suicidal self‐injury (NSSI) disorder is highly prevalent in adolescents, its relationship with pain system function and suicidality is still controversial. The present study was designed to assess the function of the nociceptive afferent pathways and the endogenous pain modulation in adolescent patients with NSSI and to longitudinally register any suicide attempt, describe its frequency and find a possible association between suicide, neurophysiological measures and psychological measures.

Methods

We enrolled 30 adolescents suffering from NSSI and 20 age‐ and gender‐matched healthy controls. Patients underwent a comprehensive psychological evaluation. Each participant underwent thermal pain thresholds of the quantitative sensory testing, laser‐evoked potential recording to study the ascending nociceptive pathway and the conditioned pain modulation testing to test the endogenous pain modulation.

Results

We found that patients with NSSI had a reduced amplitude of the N2 component of laser‐evoked potentials and an abnormal conditioned pain modulation. The amplitude of the N2 was associated with suicidal risk.

Conclusions

The deficit of the endogenous pain modulation likely depends on a saturation due to continuous pain solicitation. The strong association of a reduced amplitude of the N2 component with suicide suggests that it may serve as a possible biomarker in self‐harming adolescents.

Significance

The present study identifies the N2 component of laser‐evoked potentials as a possible neurophysiological biomarker of suicidal risk in patients with non‐suicidal self‐injury, therefore, raising the possibility for a non‐invasive test to identify subjects at higher risk of suicide among self‐harming patients.

BDNF gene expression association with suicide and psychiatric disorders in children and adolescents: (Relationship between BDNF gene expression and suicide)

OBJECTIVE

In the current study, it was aimed to investigate the relationship between BDNF gene expression and childhood suicide attempt, childhood traumatic experiences, and problem-solving skills in children and adolescents.

METHODS

The suicide group consisted of 100 children and adolescents aged 11-18 years who were referred to our outpatient department due to suicide attempt. For further comparisons, 100 children and adolescents who have no any psychiatric diagnosis were referred to our same outpatient department were selected. A sociodemographic data form, the Schedule for Affective Disorders and Schizophrenia for School-Age Children- Present and Lifetime version (K-SADS-PL), the Suicide Intent Scale (SIS), Problem Solving Inventory (PSI), and the Childhood Trauma Questionnaire (CTQ) were used for both groups. Total RNA was isolated from whole blood samples and BDNF gene expression levels were measured using quantitative real time-polymerase chain reaction (QRT-PCR).

RESULTS

The total and subscale scores of the PSI and CTQ were found to be significantly higher in the suicide group than in the control group. There was no significant difference between the groups in terms of BDNF gene expression levels. However, gene expression of BDNF was found significantly increased in patients who have any psychiatric disorder compared with the others.

CONCLUSION

Our results indicate that BDNF gene expression could be more associated with psychiatric disorders rather than suicide attempt in children and adolescents.

Sex-stratified gene-by-environment genome-wide interaction study of trauma, posttraumatic-stress, and suicidality

Epidemiologic studies recognize that trauma and posttraumatic stress are associated with heightened suicidal behavior severity, yet examination of these associations from a genetic perspective is limited. We performed a multivariate gene-by-environment genome-wide interaction study (GEWIS) of suicidality in 123,633 individuals using a covariance matrix based on 26 environments related to traumatic experiences, posttraumatic stress, social support, and socioeconomic status. We discovered five suicidality risk loci, including the male-associated rs2367967 (CWC22), which replicated in an independent cohort. All GEWIS-significant loci exhibited interaction effects where at least 5% of the sample had environmental profiles conferring opposite SNP effects from the majority. We identified PTSD as a primary driving environment for GxE at suicidality risk loci. The male suicidality GEWIS was enriched for three middle-temporal-gyrus inhibitory neuron transcriptomic profiles: SCUBE- and PVALB-expressing cells (β = 0.028, p = 3.74 × 10-4), OPRM1-expressing cells (β = 0.030, p = 0.001), and SPAG17-expressing cells (β = 0.029, p = 9.80 × 10-4). Combined with gene-based analyses (CNTN5 p association  = 2.38 × 10-9, p interaction  = 1.51 × 10-3; PSMD14 p association  = 2.04 × 10-7, p interaction  = 7.76 × 10-6; HEPACAM p association  = 2.43 × 10-6, p interaction  = 3.82 × 10-7) including information about brain chromatin interaction profiles (UBE2E3 in male neuron p = 1.07 × 10-5), our GEWIS points to extracellular matrix biology and synaptic plasticity as biological interactors with the effects of potentially modifiable lifetime traumatic experiences on genetic risk for suicidality. Characterization of molecular basis for the effects of traumatic experience and posttraumatic stress on risk of suicidal behaviors may help to identify novel targets for which more effective treatments can be developed for use in high-risk populations.

Thirty-day suicidal thoughts and behaviors among hospital workers during the first wave of the Spain COVID-19 outbreak

BACKGROUND

Healthcare workers are a key occupational group at risk for suicidal thoughts and behaviors (STB). We investigated the prevalence and correlates of STB among hospital workers during the first wave of the Spain COVID-19 outbreak (March-July 2020).

METHODS

Data come from the baseline assessment of a cohort of Spanish hospital workers (n = 5450), recruited from 10 hospitals just after the height of the coronavirus disease 2019 (COVID-19) outbreak (May 5-July 23, 2020). Web-based self-report surveys assessed 30-day STB, individual characteristics, and potentially modifiable contextual factors related to hospital workers' work and financial situation.

RESULTS

Thirty-day STB prevalence was estimated at 8.4% (4.9% passive ideation only, 3.5% active ideation with or without a plan or attempt). A total of n = 6 professionals attempted suicide in the past 30 days. In adjusted models, 30-day STB remained significantly associated with pre-pandemic lifetime mood (odds ratio [OR] = 2.92) and anxiety disorder (OR = 1.90). Significant modifiable factors included a perceived lack of coordination, communication, personnel, or supervision at work (population-attributable risk proportion [PARP] = 50.5%), and financial stress (PARP = 44.1%).

CONCLUSIONS AND RELEVANCE

Thirty-day STB among hospital workers during the first wave of the Spain COVID-19 outbreak was high. Hospital preparedness for virus outbreaks should be increased, and strong governmental policy response is needed to increase financial security among hospital workers.

Characteristics of depressed suicide attempters with remitted substance use disorders

Substance use disorder (SUD) comorbidity in mood disorders increases suicide risk. Suicide attempters with active SUD appear to have distinct characteristics but little is known whether these characteristics persist during remission and if they are related to different aspects of suicidal behavior. In this study, suicide attempters with a DSM mood disorder and remitted SUD (AT+SUD) (N = 135) were compared to those without lifetime SUD (AT-SUD) (N = 219) in terms of demographic, clinical and suicidal behavioral characteristics. Factor analyses were conducted to generate subjective distress and impulsivity/aggression factors - previously identified by our group to predict suicide risk in mood disorders. Associations between these traits and SUD history and suicidal behavior characteristics were then tested. Compared with AT-SUD, AT+SUD were more likely to be male, less educated and to have a Cluster B personality disorder. AT+SUD individuals had greater impulsivity/aggression factor scores, but comparable subjective distress scores. AT+SUD made a greater number of suicide attempts, with higher lethality, despite comparable suicide intent and degree of planning with AT-SUD. Impulsivity/aggression was higher in multiple versus single attempters, but did not correlate with suicide attempt lethality. Among suicide attempters with mood disorders, a history of lifetime SUD was associated with more frequent and more lethal suicide attempts. Among other correlates of lifetime SUD in this sample, impulsive/aggressive traits may explain greater frequency of suicide attempts. The results underscore that persons with mood disorders and lifetime SUD are at particularly high risk of frequent and lethal suicide attempts where more intensive prevention efforts are warranted.

Psychosocial interventions for self-harm in adults

BACKGROUND

Self-harm (SH; intentional self-poisoning or self-injury regardless of degree of suicidal intent or other types of motivation) is a growing problem in most counties, often repeated, and associated with suicide. There has been a substantial increase in both the number of trials and therapeutic approaches of psychosocial interventions for SH in adults. This review therefore updates a previous Cochrane Review (last published in 2016) on the role of psychosocial interventions in the treatment of SH in adults.

OBJECTIVES

To assess the effects of psychosocial interventions for self-harm (SH) compared to comparison types of care (e.g. treatment-as-usual, routine psychiatric care, enhanced usual care, active comparator) for adults (aged 18 years or older) who engage in SH.

SEARCH METHODS

We searched the Cochrane Common Mental Disorders Specialised Register, the Cochrane Library (Central Register of Controlled Trials [CENTRAL] and Cochrane Database of Systematic reviews [CDSR]), together with MEDLINE, Ovid Embase, and PsycINFO (to 4 July 2020).

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing interventions of specific psychosocial treatments versus treatment-as-usual (TAU), routine psychiatric care, enhanced usual care (EUC), active comparator, or a combination of these, in the treatment of adults with a recent (within six months of trial entry) episode of SH resulting in presentation to hospital or clinical services. The primary outcome was the occurrence of a repeated episode of SH over a maximum follow-up period of two years. Secondary outcomes included treatment adherence, depression, hopelessness, general functioning, social functioning, suicidal ideation, and suicide.

DATA COLLECTION AND ANALYSIS

We independently selected trials, extracted data, and appraised trial quality. For binary outcomes, we calculated odds ratio (ORs) and their 95% confidence intervals (CIs). For continuous outcomes, we calculated mean differences (MDs) or standardised mean differences (SMDs) and 95% CIs. The overall quality of evidence for the primary outcome (i.e. repetition of SH at post-intervention) was appraised for each intervention using the GRADE approach.

MAIN RESULTS

We included data from 76 trials with a total of 21,414 participants. Participants in these trials were predominately female (61.9%) with a mean age of 31.8 years (standard deviation [SD] 11.7 years). On the basis of data from four trials, individual cognitive behavioural therapy (CBT)-based psychotherapy may reduce repetition of SH as compared to TAU or another comparator by the end of the intervention (OR 0.35, 95% CI 0.12 to 1.02; N = 238; k = 4; GRADE: low certainty evidence), although there was imprecision in the effect estimate. At longer follow-up time points (e.g., 6- and 12-months) there was some evidence that individual CBT-based psychotherapy may reduce SH repetition. Whilst there may be a slightly lower rate of SH repetition for dialectical behaviour therapy (DBT) (66.0%) as compared to TAU or alternative psychotherapy (68.2%), the evidence remains uncertain as to whether DBT reduces absolute repetition of SH by the post-intervention assessment. On the basis of data from a single trial, mentalisation-based therapy (MBT) reduces repetition of SH and frequency of SH by the post-intervention assessment (OR 0.35, 95% CI 0.17 to 0.73; N = 134; k = 1; GRADE: high-certainty evidence). A group-based emotion-regulation psychotherapy may also reduce repetition of SH by the post-intervention assessment based on evidence from two trials by the same author group (OR 0.34, 95% CI 0.13 to 0.88; N = 83; k = 2; moderate-certainty evidence). There is probably little to no effect for different variants of DBT on absolute repetition of SH, including DBT group-based skills training, DBT individual skills training, or an experimental form of DBT in which participants were given significantly longer cognitive exposure to stressful events. The evidence remains uncertain as to whether provision of information and support, based on the Suicide Trends in At-Risk Territories (START) and the SUicide-PREvention Multisite Intervention Study on Suicidal behaviors (SUPRE-MISS) models, have any effect on repetition of SH by the post-intervention assessment. There was no evidence of a difference for psychodynamic psychotherapy, case management, general practitioner (GP) management, remote contact interventions, and other multimodal interventions, or a variety of brief emergency department-based interventions.

AUTHORS' CONCLUSIONS

Overall, there were significant methodological limitations across the trials included in this review. Given the moderate or very low quality of the available evidence, there is only uncertain evidence regarding a number of psychosocial interventions for adults who engage in SH. Psychosocial therapy based on CBT approaches may result in fewer individuals repeating SH at longer follow-up time points, although no such effect was found at the post-intervention assessment and the quality of evidence, according to the GRADE criteria, was low. Given findings in single trials, or trials by the same author group, both MBT and group-based emotion regulation therapy should be further developed and evaluated in adults. DBT may also lead to a reduction in frequency of SH. Other interventions were mostly evaluated in single trials of moderate to very low quality such that the evidence relating to the use of these interventions is inconclusive at present.

Suicidal behaviour in older age: A systematic review of risk factors associated to suicide attempts and completed suicides

In older age, several observational studies investigated risk factors for suicide attempts/completed suicides; however, contrasting evidence came from population-based setting. In the present systematic review, we described through a narrative synthesis the significant associations existing among risk factors and suicide attempts/completed suicides in subjects aged >65 years. From the 39 population-based studies selected in six different databases until February 15, 2021, we analyzed the most frequent 28 risk factors for suicidal behaviour. The risk factors more associated to suicide attempts than other variables frequently related to suicidal behavior in older age were: depressive disorders, methods employed to self-harm (particularly poisoning), and psychotropic drug utilization followed by psychological factors and disability. Moreover, male sex, violent methods to self-harm, any psychiatric disorder (depression, anxiety and bipolar disorders), a poor medical condition, stressors/bereavement, and living alone appeared to be more significant for predicting completed suicides in late life. In older age, efforts for suicide prevention should be based on strategies to assess and treat psychiatric disorders along with psychological interventions, particularly in males.

Developing Public Service Announcements to Help Prevent Suicide among Young People

Background: Suicide is the leading cause of death among young people in Australia. Media campaigns have the potential to reach a broad audience, change attitudes and behaviours, and, ultimately, help prevent suicide. Little is known about the type of content or format suicide prevention media message should take to help prevent suicide among young people. Objective: the objective of this study was to involve young people aged 18 to 24 years in developing three suicide prevention public service announcement (PSAs) targeting young people at risk of suicide appropriate for testing in a randomised controlled trial (RCT). Method: fifteen young people attended at least one of four workshops in Melbourne, Australia. The workshops focused on exploring the appropriateness of three key suicide prevention media PSAs: “Talk to someone”, “Find what works for you”, and “Life can get better”. Young people also provided input into message content, format, and design. Results: participants perceived that all three suicide prevention PSAs were useful and helpful. Participants were concerned that the PSAs may not be suitable for nonwestern cultural groups, could trivialise psychological suffering, and that the actions they promoted could seem distant or unattainable to young people at risk. The featuring of young people, especially young people with hopeful narratives of how they overcame a suicidal crisis, was considered to be an important characteristic of suicide prevention PSAs targeting young people. Conclusions: Developing suicide prevention PSAs with young people is rare but essential to better understand young people’s needs and improve the quality of suicide prevention media PSAs. Further research is needed to evaluate the impact of suicide prevention PSAs developed by young people, for young people.

Suicidality Associated With Deep Brain Stimulation in Extrapyramidal Diseases: A Critical Review and Hypotheses on Neuroanatomical and Neuroimmune Mechanisms

Deep brain stimulation (DBS) is a very well-established and effective treatment for patients with extrapyramidal diseases. Despite its generally favorable clinical efficacy, some undesirable outcomes associated with DBS have been reported. Among such complications are incidences of suicidal ideation (SI) and behavior (SB) in patients undergoing this neurosurgical procedure. However, causal associations between DBS and increased suicide risk are not demonstrated and they constitute a debated issue. In light of these observations, the main objective of this work is to provide a comprehensive and unbiased overview of the literature on suicide risk in patients who received subthalamic nucleus (STN) and internal part of globus pallidum (GPi) DBS treatment. Additionally, putative mechanisms that might be involved in the development of SI and SB in these patients as well as caveats associated with these hypotheses are introduced. Finally, we briefly propose some clinical implications, including therapeutic strategies addressing these potential disease mechanisms. While a mechanistic connection between DBS and suicidality remains a controversial topic that requires further investigation, it is of critical importance to consider suicide risk as an integral component of candidate selection and post-operative care in DBS.

Cerebrospinal fluid levels of monoamines among suicide attempters: A systematic review and random-effects meta-analysis

BACKGROUND

It remains unclear whether the dopaminergic and noradrenergic systems may be implied in suicide attempt risk. In addition, although the serotonergic system has been extensively studied, no formal meta-analysis has been performed to examine its association with suicide attempt.

METHODS

Using PRISMA methodology, we performed a systematic literature review and random-effects meta-analyses of the differences in cerebrospinal fluid (CSF) levels of 5-HIAA, HVA and MHPG between suicide attempters and individuals who never attempted suicide.

RESULTS

We identified 30 studies including 937 suicide attempters and 1128 non-attempters; 29 of them measured CSF levels of 5-HIAA, 22 measured CSF levels of HVA and 14 measured CSF levels of MHPG. CSF levels of 5-HIAA and HVA were significantly lower in suicide attempters than in non-attempters [SMD = -0.43 (95% CI: -0.71 to -0.15; p < 0.01) and SMD = -0.45 (95% CI: -0.72 to -0.19; p < 0.01), respectively]. We did not find a significant association between CSF MHPG levels and suicide attempt.

LIMITATIONS

Our analyses relied on a limited number of studies of good quality and most studies included small sample sizes.

CONCLUSION

Both serotonin and dopamine systems may play a role in suicide attempt risk. Our findings suggest that a silo approach to biomarkers should be phased out in favor of the study of multiple systems in parallel and in the same populations to progress in the identification of the biological components independently associated with suicide risk, with the goal of identifying new treatment targets and improving suicide risk prediction.

Visual memory improvement in adolescents at high risk for suicide who are receiving psychotherapy at a community clinic

The current study aims to: 1) investigate cognitive differences among adolescents at risk for suicide versus healthy controls (HC) and 2) identify cognitive changes associated with response to psychotherapy among adolescents at high risk for suicide. Thirty-five adolescents at high risk for suicide (HR), and 14 HC adolescents were recruited. Clinical and cognitive assessments were conducted in both groups at baseline and 16 weeks later (after the patients completed psychotherapy). HR and HC adolescents were compared at baseline and at completion of the study. We also conducted further analysis by separating into two groups the HR adolescents who responded to psychotherapy (n=17) and those who did not (n=11). At baseline, the HR group had significantly lower performance on verbal memory and processing speed than the HC group. At week 16, HR adolescents performed as well as HC adolescents in all cognitive domains. Among patients, better performance on visual memory was observed in those who responded to psychotherapy compared to those who did not. We concluded that lower performance on verbal memory and processing speed may be associated with a high risk for suicide among adolescents. Improvement in visual memory might be related to a lower risk for suicide in adolescents.

Candidate pharmacological treatments for substance use disorder and suicide identified by gene co-expression network-based drug repositioning

Patients with substance use disorders (SUD) are at high risk to die by suicide. So far, the neurobiology of the suicide-SUD association has not been elucidated. This study aimed to identify potential pharmacological targets among hub genes from brain gene co-expression networks of individuals with SUD in a suicidal and non-suicidal context. Post-mortem samples from the prefrontal cortex of 79 individuals were analyzed. Individuals were classified into the following groups: suicides with SUD (n = 28), suicides without SUD (n = 23), nonsuicides with SUD (n = 9), nonsuicides without SUD (n = 19). Gene expression profiles were evaluated with the Illumina HumanHT-12 v4 array. Co-expression networks were constructed in WGCNA using the differentially expressed genes found in the comparisons: (a) suicides with and without SUD and (b) nonsuicides with and without SUD. Hub genes were selected for drug-gene interaction testing in the DGIdb database. Among drugs interacting with hub genes in suicides we found MAOA inhibitors and dextromethorphan. In the nonsuicide individuals, we found interactions with eglumegad and antipsychotics (olanzapine, clozapine, loxapine). Modafinil was found to interact with genes in both suicides and nonsuicides. These drugs represent possible candidate treatments for patients with SUD with and without suicidal behavior and their study in each context is encouraged.

Auditory evoked potentials and suicidal behaviors in patients with major depressive disorders

Loudness dependence of auditory evoked potentials (LDAEP) has been proposed as a biological marker of central serotonergic activity related to suicides. This study’s objective was to analyze the difference in LDAEP between depressed patients with suicide attempts (SA) and suicidal ideation (SI). It included 130 participants (45 depressed patients with SA, 49 depressed patients with SI, and 36 healthy controls) aged > 18 years who exhibited LDAEP during electroencephalography. Psychological characteristics and event-related potentials of the three groups were compared. There was no significant difference in LDAEP between major depressive disorder (MDD) patients with SA and SI (p = 0.59). MDD patients with SI, who attempted suicide had significantly lower LDAEP than healthy controls (p = 0.01 and p = 0.01, respectively). However, the significance disappeared when psychological characteristics were controlled. Our results suggest that LDAEP might not be possible biomarkers for suicidal behaviors in patients with MDD. Further studies to assess the biological basis of suicide and identify the underlying dimensions that mediate the relationship between the biological basis and suicidal behaviors will be needed.

Prevalence, course, and determinants of suicide ideation and attempts in patients with a depressive and/or anxiety disorder: A review of NESDA findings

BACKGROUND

Depressive and anxiety disorders are often associated with suicide ideation (SI) and attempt (SA). However, analyses of prevalence, course, and more specific risk mechanisms are needed to improve knowledge and detection of high risk individuals with depressive and anxiety disorders. Previous studies often lacked statistical power, assessment of detailed determinants and follow-up measurements.

METHODS

The Netherlands Study of Depression and Anxiety (NESDA), a large cohort study, overcomes some earlier limitations. Scale for Suicide Ideation and Compositive Interview Diagnostic Instrument data were analyzed to report on prevalence of SI and SA. Additionally, important sociodemographic, clinical, psychological, environmental, and neurobiological determinants and course of SI and SA identified in depressive and/or anxiety disorder respondents in 16 NESDA articles were summarized.

RESULTS

Within respondents with 12-month diagnosis (n=1,783), SI and 12-month SA prevalence ranged from 17.1-20.1% and 0.8-3.0% respectively across 5 waves during 9-year follow-up and SI was highly recurrent. Both SI and SA were especially associated with comorbid depression and anxiety, higher clinical severity, sleep dysfunctions, higher aggression and hopelessness, and childhood trauma. In the (neuro)biological domain, SI was linked with immune dysregulation and SA with abnormal brain activity during emotion processing and genetic risk.

LIMITATIONS

Most articles were cross-sectional in nature, preventing causal inferences and no conclusions could be drawn about the overall magnitude of results.

CONCLUSION

SI and SA are multifactorial phenomena and especially prevalent amongst comorbid depressive and anxiety respondents. Considering many overlapping SI and SA determinants, more neurobiological determinants and use of innovative methodological techniques are desirable.

Suicide Risk and Addiction: The Impact of Alcohol and Opioid Use Disorders

Purpose of Review

Suicide is a major public health concern and a leading cause of death in the US. Alcohol and opioid use disorders (AUD/OUD) significantly increase risk for suicidal ideation, attempts, and death, and are the two most frequently implicated substances in suicide risk. We provide a brief overview of shared risk factors and pathways in the pathogenesis of AUD/OUD and suicidal thoughts and behaviors. We also review clinical recommendations on inpatient care, pharmacotherapy, and psychotherapeutic interventions for people with AUD/OUD and co-occurring suicidal ideation and behavior.

Recent Findings

Among people with an underlying vulnerability to risk-taking and impulsive behaviors, chronic alcohol intoxication can increase maladaptive coping behaviors and hinder self-regulation, thereby increasing the risk of suicide. Additionally, chronic opioid use can result in neurobiological changes that lead to increases in negative affective states, jointly contributing to suicide risk and continued opioid use. Despite significantly elevated suicide risk in individuals with AUD/OUD, there is a dearth of research on pharmacological and psychosocial interventions for co-occurring AUD/OUD and suicidal ideation and behavior.

Summary

Further research is needed to understand the effects of alcohol and opioid use on suicide risk, as well as address notable gaps in the literature on psychosocial and pharmacological interventions to lower risk for suicide among individuals with AUD/OUD.

Interventions for self-harm in children and adolescents

BACKGROUND

Self-harm (SH; intentional self-poisoning or self-injury regardless of degree of suicidal intent or other types of motivation) is a growing problem in most countries, often repeated, and associated with suicide. Evidence assessing the effectiveness of interventions in the treatment of SH in children and adolescents is lacking, especially when compared with the evidence for psychosocial interventions in adults. This review therefore updates a previous Cochrane Review (last published in 2015) on the role of interventions for SH in children and adolescents.

OBJECTIVES

To assess the effects of psychosocial interventions or pharmacological agents or natural products for SH compared to comparison types of care (e.g. treatment-as-usual, routine psychiatric care, enhanced usual care, active comparator, placebo, alternative pharmacological treatment, or a combination of these) for children and adolescents (up to 18 years of age) who engage in SH.

SEARCH METHODS

We searched the Cochrane Common Mental Disorders Specialized Register, the Cochrane Library (Central Register of Controlled Trials [CENTRAL] and Cochrane Database of Systematic Reviews [CDSR]), together with MEDLINE, Ovid Embase, and PsycINFO (to 4 July 2020).

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing specific psychosocial interventions or pharmacological agents or natural products with treatment-as-usual (TAU), routine psychiatric care, enhanced usual care (EUC), active comparator, placebo, alternative pharmacological treatment, or a combination of these, in children and adolescents with a recent (within six months of trial entry) episode of SH resulting in presentation to hospital or clinical services. The primary outcome was the occurrence of a repeated episode of SH over a maximum follow-up period of two years. Secondary outcomes included treatment adherence, depression, hopelessness, general functioning, social functioning, suicidal ideation, and suicide.

DATA COLLECTION AND ANALYSIS

We independently selected trials, extracted data, and appraised trial quality. For binary outcomes, we calculated odds ratios (ORs) and their 95% confidence internals (CIs). For continuous outcomes, we calculated the mean difference (MD) or standardised mean difference (SMD) and 95% CIs. The overall quality of evidence for the primary outcome (i.e. repetition of SH at post-intervention) was appraised for each intervention using the GRADE approach.

MAIN RESULTS

We included data from 17 trials with a total of 2280 participants. Participants in these trials were predominately female (87.6%) with a mean age of 14.7 years (standard deviation (SD) 1.5 years). The trials included in this review investigated the effectiveness of various forms of psychosocial interventions. None of the included trials evaluated the effectiveness of pharmacological agents in this clinical population. There was a lower rate of SH repetition for DBT-A (30%) as compared to TAU, EUC, or alternative psychotherapy (43%) on repetition of SH at post-intervention in four trials (OR 0.46, 95% CI 0.26 to 0.82; N = 270; k = 4; high-certainty evidence). There may be no evidence of a difference for individual cognitive behavioural therapy (CBT)-based psychotherapy and TAU for repetition of SH at post-intervention (OR 0.93, 95% CI 0.12 to 7.24; N = 51; k = 2; low-certainty evidence). We are uncertain whether mentalisation based therapy for adolescents (MBT-A) reduces repetition of SH at post-intervention as compared to TAU (OR 0.70, 95% CI 0.06 to 8.46; N = 85; k = 2; very low-certainty evidence). Heterogeneity for this outcome was substantial ( I² = 68%). There is probably no evidence of a difference between family therapy and either TAU or EUC on repetition of SH at post-intervention (OR 1.00, 95% CI 0.49 to 2.07; N = 191; k = 2; moderate-certainty evidence). However, there was no evidence of a difference for compliance enhancement approaches on repetition of SH by the six-month follow-up assessment, for group-based psychotherapy at the six- or 12-month follow-up assessments, for a remote contact intervention (emergency cards) at the 12-month assessment, or for therapeutic assessment at the 12- or 24-month follow-up assessments.

AUTHORS' CONCLUSIONS

Given the moderate or very low quality of the available evidence, and the small number of trials identified, there is only uncertain evidence regarding a number of psychosocial interventions in children and adolescents who engage in SH. Further evaluation of DBT-A is warranted. Given the evidence for its benefit in adults who engage in SH, individual CBT-based psychotherapy should also be further developed and evaluated in children and adolescents.

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.

Low dose oral ketamine treatment in chronic suicidality: An open-label pilot study

Recently, low-dose ketamine has been proposed as a rapid-acting treatment option for suicidality. The majority of studies to date have utilised intravenous (IV) ketamine, however, this route of administration has limitations. On the other hand, oral ketamine can be administered in a range of settings, which is important in treating suicidality, although studies as to safety and feasibility are lacking. n = 32 adults (aged 22-72 years; 53% female) with chronic suicidal thoughts participated in the Oral Ketamine Trial on Suicidality (OKTOS), an open-label trial of sub-anaesthetic doses of oral ketamine over 6 weeks. Participants commenced with 0.5 mg/kg of ketamine, which was titrated to a maximum 3.0 mg/kg. Follow-up assessments occurred at 4 weeks after the final dose. The primary outcome measure was the Beck Scale for Suicide Ideation (BSS) and secondary measures included scales for suicidality and depressive symptoms, and measures of functioning and well-being. Mean BSS scores significantly reduced from a high level of suicidal ideation at the pre-ketamine (week 0) timepoint to below the clinical threshold at the post-ketamine (week 6) timepoint. The proportion of participants that achieved clinical improvement within the first 6 weeks was 69%, whereas 50% achieved a significant improvement by the follow-up (week 10) timepoint. Six weeks of oral ketamine treatment in participants with chronic suicidality led to significant reduction in suicidal ideation. The response observed in this study is consistent with IV ketamine trials, suggesting that oral administration is a feasible and tolerable alternative treatment for chronic suicidality.