The neurobiology of suicide

Challenges in the evaluation of suicide prevention measures and quality of suicide data in Germany, Austria, and Switzerland: findings from qualitative expert interviews

BACKGROUND

Suicide prevention requires diverse, integrated, and evidence-based measures. Comprehensive evaluation of interventions and reliable suicide data are crucial for guiding policy-making and advancing suicide prevention efforts. This study aimed to analyze current issues and gaps in the evaluation of suicide prevention measures and the quality of suicide data in Germany, Austria, and Switzerland to derive specific recommendations for improvement.

METHODS

Online, semi-structured interviews were conducted with 36 experts in suicide prevention from Germany, Austria, and Switzerland, covering insights from policy, science, and practice. The interviews took place between September 2022 and February 2023, were audio-recorded, transcribed verbatim, and analyzed using the Framework method.

RESULTS

While solid evidence supports the effectiveness of some suicide prevention interventions, experts indicated that the evaluation of many other measures is weak. Conducting effectiveness studies in suicide prevention presents a range of methodological and practical challenges, including recruitment difficulties, choosing adequate outcome criteria, ethical considerations, and trade-offs in allocating resources to evaluation efforts. Many interviewees rated the quality of national suicide statistics in Germany, Austria, and Switzerland as comparatively high. However, they noted limitations in the scope, timeliness, and reliability of these data, prompting some regions to implement their own suicide monitoring systems. None of the three countries has national routine data on suicide attempts.

CONCLUSION

While some challenges in evaluating suicide prevention measures are inevitable, others can potentially be mitigated. Evaluations could be enhanced by combining traditional and innovative research designs, including intermediate outcomes and factors concerning the implementation process, and employing participatory and transdisciplinary research to engage different stakeholders. Reliable suicide data are essential for identifying trends, supporting research, and designing targeted prevention measures. To improve the quality of suicide data, a standardized monitoring approach, including uniform definitions, trained professionals, and cross-sector agreement on leadership and financing, should be pursued. This study provides actionable recommendations and highlights existing good practice approaches, thereby supporting decision-makers and providing guidance for advancing suicide prevention on a broader scale.

Suicide, neuroinflammation and other physiological alterations

Suicide is considered one of the major public health problems worldwide, being the second leading cause of death in the 15-29 age group. It is estimated that every 40s someone in the world commits suicide. The social taboo surrounding this phenomenon as well as the fact that suicide prevention measures currently fail to avoid deaths from this cause, means that more research is needed to understand its mechanisms. The present narrative review on suicide tries to point out several important aspects, such as risk factors or the dynamics of suicide, as well as the current findings in the field of physiology that could offer advances in the understanding of suicide. Subjective measures of risk such as scales and questionnaires are not effective alone, whereas the objective measures can be addressed from physiology. Thus, an increased neuroinflammation in people who take their own lives has been found, with an increase in inflammatory markers such as interleukin-6 and other cytokines in plasma or cerebrospinal fluid. Also, the hyperactivity of the hypothalamic-pituitary-adrenal axis and a decrease in serotonin or in vitamin D levels seems to also be involved. In conclusion, this review could help to understand which factors can trigger an increased risk of dying by suicide, as well as pointing out those alterations that occur in the body when someone attempt to commit suicide or succeeds in taking their own life. There is a need for more multidisciplinary approaches that address suicide to help to raise awareness of the relevance of this problem that causes the death of thousands of people every year.

Exploring the neurocognitive correlates of suicidal ideation in major depressive disorder: The role of frontoparietal and default mode networks

Suicidal ideation (SI) is a common symptom of major depressive disorder (MDD), often accompanied by cognitive alterations and emotional dysregulation. However, it is unclear whether cognitive dysfunction in patients with MDD is related to the presence or absence of SI and impaired connectivity within or between large-scale neurocognitive networks. Previous studies have shown that the frontoparietal network (FPN) and default mode network (DMN) are critical for cognitive control and emotional regulation. Participants were 51 MDD patients with suicidal ideation (MDDSI), 52 MDD patients without suicidal ideation (MDDNSI), and 55 healthy controls (HC). Using areas located within FPN and DMN networks as regions of interest (ROIs), we compared the cognitive performance of the three groups and the strength of the resting state functional connections (RSFC) within and between the FPN and DMN networks. Additionally, we examined the correlation between the strength of FC within the FPN and cognitive function in the SI group. Furthermore, network-based statistics (NBS) were used to correct for the strength of FPN and DMN functional connections. The study identified significant cognitive deficits in MDD patients. Reduced strength of FC was observed within the FPN and DMN networks in the SI group compared to the NSI group. In the SI group, the strength of FC within the FPN network was positively correlated with attention/vigilance. These insights underscore the critical roles of the FPN and DMN in the suicidal ideation, shedding light on the cognitively relevant neurobiological characteristics of MDDSI, providing new insights into the neural mechanisms of MDDSI. URL: https://www.chictr.org.cn/bin/project/edit?pid=131537. Registration number: ChiCTR2100049646.

Using the Strategy of Genome-Wide Association Studies to Identify Genetic Markers of Suicidal Behavior: A Narrative Review

BACKGROUND

Several studies involving various suicidal phenotypes based on the strategy of the search of genome-wide associations with single nucleotide polymorphisms have been performed recently. These studies need to be generalized.

AIM

To systematize the findings of a number of genome-wide association studies (GWAS) for suicidal phenotypes, annotate the identified markers, analyze their functionality, and possibly substantiate the hypothesis holding that these phenotypes reflect a nonspecific set of gene variants that are relevant as relates to stress-vulnerability as a key endophenotype of suicidal behavior (SB).

METHODS

A search on the PubMed and related resources using the combinations "suicide AND GWAS" and "suicidal behavior AND GWAS" was performed. It yielded a total of 34 independent studies and meta-analyses.

RESULTS

For the 10 years since such studies emerged, they have undergone significant progress. Estimates of the SNP heritability of SB in some cases are comparable with estimates of heritability based on the twin method. Many studies show a high genetic correlation with the genomic markers of the most common mental disorders (depression, bipolar disorder, schizophrenia, post-traumatic stress disorder). At the same time, a genomic architecture specific to SB is also encountered. Studies utilizing the GWAS strategy have not revealed any associations of SB with candidate genes that had been previously studied in detail (different neurotransmitters, stress response system, polyamines, etc.). Frequently reported findings from various studies belong in three main groups: 1) genes involved in cell interactions, neurogenesis, the development of brain structures, inflammation, and the immune responses; 2) genes encoding receptors for neurotrophins and various components of the intracellular signaling systems involved in synaptic plasticity, embryonic development, and carcinogenesis; and 3) genes encoding various neuro-specific proteins and regulators.

CONCLUSION

In general, GWAS in the field of suicidology mainly serve the purpose of a deeper understanding of the pathophysiology of suicidal behavior. However, they also demonstrate growing capability in terms of predicting and preventing suicide, especially when calculating the polygenic risk score among certain populations (psychiatric patients) and in combination with tests of different modalities. From our point of view, there exists a set of markers revealed by the GWAS strategy that seems to point to a leading role played by stress vulnerability, an endophenotype that is formed during early development and which subsequently comes to play the role of key pathogenetic mechanism in SB.

Changes in Rates of Suicide by Mass Shooters, 1980-2019

OBJECTIVE

The rate of worldwide mass shootings increased almost 400% over the last 40 years. About 30% are followed by the perpetrator's fatal or nonfatal suicide attempt.

METHOD

We examined the rate of fatal and nonfatal attempts among 528 mass shooters over the last 40 years and their relationship to detected mental illness to better understand this specific context of suicide. We collected information on U.S.-based, personal-cause mass murders that involved one or more firearms, from online sources.

RESULTS

A greater proportion of mass shooters from 2000 to 2019 took or attempted to take their own lives (40.5%) compared with those from 1980 to 1999 (23.2%, p < 0.001). More than double the proportion of perpetrators who made a fatal or nonfatal suicide attempt had a history of non-psychotic psychiatric/neurologic symptoms (38.9%), compared with perpetrators who did not make a fatal or nonfatal suicide attempt (18.1%; p < 0.001). Among mass shooters who made fatal or nonfatal suicide attempts, 77 of 175 (44%) did not have any recorded psychiatric, neurologic, or substance use condition. Of the 98 mass shooters who made fatal or non-fatal suicide attempts and had a psychiatric, substance use, or neurologic condition, 41 had depressive disorders.

CONCLUSION

It is possible that a lack of information about the perpetrators' mental health or suicidal ideation led to an underestimation of their prevalence. These data suggest that suicide associated with mass shootings may represent a specific context for suicide, and approaches such as psychological autopsy can help to ascertain when psychiatric illness mediates the relationship between mass shootings and suicide.

Interplay of combat deployment harassment, testosterone concentrations and post-deployment suicide risk in male veterans

OBJECTIVE

Many combat veterans exhibit suicidal ideation and behaviour, but the relationships among experiences occurring during combat deployment and suicidality are still not fully understood. In this study, we tested the hypothesis that harassment during a combat deployment is associated with post-deployment suicidality and testosterone function.

METHODS

Male combat veterans who made post-deployment suicide attempts and demographically matched veterans without a history of suicide attempts were enrolled in the study. Demographic and clinical parameters of study participants were assessed and recorded. Study participants were interviewed by a trained clinician using the Mini-International Neuropsychiatric Interview (MINI), the Deployment Risk and Resilience Inventory (DRRI) – Relationships within unit scale, the Scale for Suicidal Ideation (SSI), and the Brown–Goodwin Aggression Scale. Free testosterone levels were assessed in morning blood samples.

RESULTS

DRRI harassment scores were higher and free testosterone levels were lower among suicide attempters in comparison with non-attempters. In the whole sample, DRRI harassment scores positively correlated with SSI scores and negatively correlated with free testosterone levels. Free testosterone levels negatively correlated with SSI scores. Aggression scale scores positively correlated with DRRI harassment scores among non-attempters but not among attempters.

CONCLUSION

Our observations that harassment scores are associated with suicidality and testosterone levels, and suicidality is associated with testosterone levels may indicate that there is a link between deployment harassment, testosterone function and suicidality.

The Experience of Survivors of Firearm Suicide Attempts: A Retrospective Case Series

Objective

We sought to identify people who survived firearm suicide attempts to describe the acute stressors, substance use, and mental health conditions related to the attempt.

Background

Most firearm deaths in the United States are the result of suicide. Because firearm suicide attempts have a case fatality rate of approximately 90%, little is known about the precipitating factors that lead to firearm suicide attempts.

Methods

We conducted a retrospective case series of patients admitted to a large hospital system between 2000 and 2019 who survived intentional, self-inflicted gunshot wounds to the head. Through the electronic medical record, we collected information about acute stressors, substance use, and mental health diagnoses before or at the time of the suicide attempt.

Results

Thirty-four patients were included in the study cohort. Patients were predominantly White (74%) and male (88%), with a mean age of 44 (range, 14-82). Nineteen (56%) patients were acutely intoxicated with alcohol upon hospitalization and 17 (50%) patients had a positive urine drug screen. Acute stressors involving interpersonal relationships (53%), work/school (32%), and legal disputes (18%), among others, were documented in 82% of patients. Most patients (65%) had been diagnosed with depression before their index hospitalization. Most patients were discharged to an acute rehabilitation center (41%) or an inpatient psychiatric facility (41%).

Conclusions

Acute stress and alcohol intoxication were common in this cohort of patients who attempted suicide using firearms. These data offer an ability to learn from the experience of survivors of firearm suicide attempts, a rare population.

Omics Approaches to Investigate the Pathogenesis of Suicide

Suicide is the second leading cause of death in U.S. adolescents and young adults and is generally associated with a psychiatric disorder. Suicidal behavior has a complex etiology and pathogenesis. Moderate heritability suggests genetic causes. Associations between childhood and recent life adversity indicate contributions from epigenetic factors. Genomic contributions to suicide pathogenesis remain largely unknown. This article is based on a workshop held to design strategies to identify molecular drivers of suicide neurobiology that would be putative new treatment targets. The panel determined that while bulk tissue studies provide comprehensive information, single-nucleus approaches that identify cell type-specific changes are needed. While single-nuclei techniques lack information on cytoplasm, processes, spines, and synapses, spatial multiomic technologies on intact tissue detect cell alterations specific to brain tissue layers and subregions. Because suicide has genetic and environmental drivers, multiomic approaches that combine cell type-specific epigenome, transcriptome, and proteome provide a more complete picture of pathogenesis. To determine the direction of effect of suicide risk gene variants on RNA and protein expression and how these interact with epigenetic marks, single-nuclei and spatial multiomics quantitative trait loci maps should be integrated with whole-genome sequencing and genome-wide association databases. The workshop concluded with a recommendation for the formation of an international suicide biology consortium that will bring together brain banks and investigators with expertise in cutting-edge omics technologies to delineate the biology of suicide and identify novel potential treatment targets to be tested in cellular and animal models for drug and biomarker discovery to guide suicide prevention.

Trends in cancer-related suicide in the United States: a population-based epidemiology study spanning 40 years of data

Large cohort studies examining trends in cancer-related suicide are lacking. We analyzed data from the Surveillance, Epidemiology, and End Results (SEER) database, encompassing a total of 4,870,410 patients diagnosed with cancer from 1975 to 2017 in the United States. Joinpoint regression was used to estimate the annual percent change (APC) and average annual percentage change (AAPC) of age-adjusted rates of suicide. In the past 40 years, we revealed a gradual increase in cancer-related suicide rates from 1975 to 1989, followed by a gradual decrease from 1989 to 2013, and a marked decrease from 2013 to 2017. These trends suggested the potential impact of advancements in psychosocial care for patients with cancer in contributing to the observed decrease in suicide rates.

Post-Roe v Wade psychiatry: legal, clinical, and ethical challenges in psychiatry under abortion bans

In recent history, the world has witnessed a trend towards liberalization of abortion laws driven by an increasing understanding of the negative personal and public health consequences of criminalizing abortion. By contrast, several countries have recently implemented restrictive reproductive laws, joining the 112 countries where access to abortion care is banned completely or with narrow exceptions. On June 24, 2022, the US Supreme Court ruling in Dobbs v Jackson Women's Health Organization overturned its landmark decisions in Roe v Wade that established abortion until the point of viability of the fetus as a constitutional right. After Roe v Wade having been overturned, it is projected that many women in the USA will be prevented from accessing safe abortion care. Importantly, abortion bans not only impose constraints on patient autonomy, they also restrict physicians' ability to practice evidence-based medicine, which will negatively impact psychiatric care. It is therefore crucial for the practicing psychiatrist to be familiar with this new legal landscape. In this Personal View, we aim to provide a topical overview to help clinicians gain a clear understanding of legal, clinical, and ethical responsibilities, focusing on the USA. We also discuss the reality that psychiatrists might be called upon to determine medical necessity for an abortion on psychiatric grounds, which is new for most US psychiatrists. We predict that psychiatrists will be confronted with very difficult situations in which lawful and ethical conduct might be incongruent, and that abortion bans will result in greater numbers of patients needing psychiatric care from a system that is ill-prepared for additional demands.

Causal relationships between serum albumin, neuroticism and suicidal ideation in depressed patients: A Mendelian randomization study

Although serum albumin and neuroticism have revealed a strong association with suicidal ideation in individuals with depression, the causal relationship between them is uncertain. This study analyzed the causal association of serum albumin, neuroticism and suicidal ideation using large-scale GWAS data and Univariable Mendelian Randomization (UVMR) methods. The Multivariable MR (MVMR) analysis was used to explore the causal pathways. UVMR analysis revealed that genetically determined serum albumin is causally associated with neuroticism (β = -0.006 S.D.; 95 % CI: 0.009, -0.002; p = 0.003) and suicidal ideation (β = 0.009 S.D.; 95 % CI: 0.001, 0.016; p = 0.037); and that neuroticism mediates 100 % of the causal association between serum albumin and suicidal ideation in individuals with depression. These findings suggest genetic evidence for the causal effect of serum albumin on suicidal ideation in depressed patients and the significant mediation effect of neuroticism on this causal association. This study proves the protective role of serum albumin for neuroticism and the riskiness of personality traits for suicidal ideation in individuals with depression.

Workplace interventions to prevent suicide: A scoping review

OBJECTIVES

To map organisational interventions for workplace suicide prevention, identifying the effects, mechanisms, moderators, implementation and economic costs, and how interventions are evaluated.

BACKGROUND

Suicide is a devastating event that can have a profound and lasting impact on the individuals and families affected, with the highest rates found among adults of work age. Employers have a legal and ethical responsibility to provide a safe working environment for their employees, which includes addressing the issue of suicide and promoting mental health and well-being.

METHODS

A realist perspective was taken, to identify within organisational suicide prevention interventions, what works, for whom and in what circumstances. Published and unpublished studies in six databases were searched. To extract and map data on the interventions the Effect, Mechanism, Moderator, Implementation, Economic (EMMIE) framework was used. Mechanisms were deductively analysed against Bronfenbrenner's socio-ecological model.

RESULTS

From 3187 records screened, 46 papers describing 36 interventions within the military, healthcare, the construction industry, emergency services, office workers, veterinary surgeons, the energy sector and higher education. Most mechanisms were aimed at the individual's immediate environment, with the most common being education or training on recognising signs of stress, suicidality or mental illness in oneself. Studies examined the effectiveness of interventions in terms of suicide rates, suicidality or symptoms of mental illness, and changes in perceptions, attitudes or beliefs, with most reporting positive results. Few studies reported economic costs but those that did suggested that the interventions are cost-effective.

CONCLUSIONS

It seems likely that organisational suicide prevention programmes can have a positive impact on attitudes and beliefs towards suicide as well reducing the risk of suicide. Education, to support individuals to recognise the signs and symptoms of stress, mental ill health and suicidality in both themselves and others, is likely to be an effective starting point for successful interventions.

Variations in Suicide Risk and Risk Factors After Hospitalization for Depression in Finland, 1996-2017

Importance

Although incidence of suicide in depression varies remarkably temporally, risk factors have been modeled as constant and remain uncharted in the short term. How effectively factors measured at one point in time predict risk at different time points is unknown.

Objective

To examine the absolute risk and risk factors for suicide in hospitalized patients with depression starting from the first days after discharge up to 2 years and to evaluate whether the size of relative risk by factor displays temporal patterns over consecutive phases of follow-up.

Design, Setting, and Participants

This population-based study using Finnish registers (hospital discharge, population, and cause of death registers) included all hospitalizations for depression as the principal diagnosis in Finland from 1996 to 2017, with a maximum follow-up of 2 years. Data were analyzed from January 2022 to November 2023.

Main Outcomes and Measures

Incidence rate (IR), IR ratios, hazard functions, and hazard ratios for suicide by consecutive time periods (0 to 3 days, 4 to 7 days, 7 to 30 days, 31 to 90 days, 91 to 365 days, and 1 to 2 years) since discharge.

Results

This study included 193 197 hospitalizations among 91 161 individuals, of whom 51 197 (56.2%) were female, and the mean (SD) age was 44.0 (17.3) years. Altogether, patients were followed up to 226 615 person-years. A total of 1219 men and 757 women died of suicide. Incidence of suicide was extremely high during the first days after discharge (IR of 6062 [95% CI, 4963-7404] per 100 000 on days 0 to 3; IR of 3884 [95% CI, 3119-4835] per 100 000 on days 4 to 7) and declined thereafter. Several factors were associated with risk of suicide over the first days after discharge. Current suicide attempt by hanging or firearms increased the risk of suicide most on days 0 to 3 (IR ratio, 18.9; 95% CI, 3.1-59.8) and on days 0 to 7 (IR ratio, 10.1; 95% CI, 1.7-31.5). Temporal patterns of the size of the relative risk diverged over time, being constant, declining, or increasing. Clinical factors had the strongest association immediately. Relative risk remained constant among men and even increased among those with alcohol or substance use disorder.

Conclusions and Relevance

In this study, patients hospitalized for depression had extremely high risk of suicide during the first days after discharge. Thereafter, incidence declined steeply but remained high. Within the periods of the highest risk of suicide, several factors increased overall risk manyfold. Risk factors' observed potencies varied over time and had characteristic temporal patterns.

Electrochemical and biosensor techniques to monitor neurotransmitter changes with depression

Depression is a common mental illness. However, its current treatments, like selective serotonin reuptake inhibitors (SSRIs) and micro-dosing ketamine, are extremely variable between patients and not well understood. Three neurotransmitters: serotonin, histamine, and glutamate, have been proposed to be key mediators of depression. This review focuses on analytical methods to quantify these neurotransmitters to better understand neurological mechanisms of depression and how they are altered during treatment. To quantitatively measure serotonin and histamine, electrochemical techniques such as chronoamperometry and fast-scan cyclic voltammetry (FSCV) have been improved to study how specific molecular targets, like transporters and receptors, change with antidepressants and inflammation. Specifically, these studies show that different SSRIs have unique effects on serotonin reuptake and release. Histamine is normally elevated during stress, and a new inflammation hypothesis of depression links histamine and cytokine release. Electrochemical measurements revealed that stress increases histamine, decreases serotonin, and leads to changes in cytokines, like interleukin-6. Biosensors can also measure non-electroactive neurotransmitters, including glutamate and cytokines. In particular, new genetic sensors have shown how glutamate changes with chronic stress, as well as with ketamine treatment. These techniques have been used to characterize how ketamine changes glutamate and serotonin, and to understand how it is different from SSRIs. This review briefly outlines how these electrochemical techniques work, but primarily highlights how they have been used to understand the mechanisms of depression. Future studies should explore multiplexing techniques and personalized medicine using biomarkers in order to investigate multi-analyte changes to antidepressants.

Suicidal ideation, attempt, and its associated factors among adult HIV/AIDS patients in Ethiopia: A systematic review and meta-analysis study

BACKGROUND

WHO statistics show that someone attempts suicide every three seconds and commits suicide every 40 seconds somewhere in the world. There is a scarcity of aggregate evidence in Ethiopia. The aim of this review was to assess the pooled prevalence of suicidal ideation, attempts, and associated factors among adult HIV/AIDS patients in Ethiopia to fill this gap.

METHODS

We extensively searched the bibliographic databases of PubMed, MEDLINE, Scopus, Google Scholar, and the Web of Science to obtain eligible studies. Further screening for a reference list of articles was also done. The Microsoft Excel Spreadsheet was used to extract data, and Stata 17 was used for analysis. To check heterogeneity, the Higgs I2 and Cochran's Q tests were employed. Sensitivity and subgroup analysis were implemented. To detect publication bias, Egger's test and funnel plots were used.

RESULTS

The pooled prevalence of suicidal ideation and attempts among adult HIV/AIDS patients in Ethiopia was 20.3 with a 95% CI (14, 26.5) and 11.1 with a 95% CI (6.6, 15.5), respectively. Living alone (AOR 4.98; 95% CI: 2.96-8.37), having comorbidity or other opportunistic infection (AOR 4.67; 95% CI: 2.57-8.48), female sex (AOR 2.86; 95% CI: 1.76, 4.62), having WHO clinical stage III of HIV (AOR 3.69; 95% CI: 2.15, 6.32), having WHO clinical stage IV of HIV (AOR 5.43; 95% CI: 2.81, 10.53), having co-morbid depression (AOR 5.25; 95% CI: 4.05, 6.80), having perceived HIV stigma (AOR 2.53; 95% CI: 1.67, 3.84), and having family history of suicidal attempt (AOR 2.79; 95% CI: 1.38, 5.66) were significantly associated with suicidal ideation. Being female (AOR 4.33; 95% CI: 2.36, 7.96), having opportunistic infections (AOR 2.73; 95% CI: 1.69, 4.41), having WHO clinical stage III of HIV (AOR 3.78; 95% CI: 2.04, 7.03), having co-morbid depression (AOR 3.47; 95% CI: 2.38, 5.05), having poor social support (AOR 3.02; 95% CI: 1.78, 5.13), and having WHO clinical stage IV (AOR 7.39; 95% CI: 3.54, 15.41) were significantly associated with suicidal attempts.

CONCLUSION

The pooled magnitude of suicidal ideation and attempt was high, and factors like opportunistic infection, WHO clinical stage III of HIV, WHO clinical stage III of HIV, and co-morbid depression were related to both suicidal ideation and attempt. Clinicians should be geared towards this mental health problem in HIV patients during management.

Distinct correlation network of clinical characteristics in suicide attempters having adolescent major depressive disorder with non-suicidal self-injury

Suicidal behavior and non-suicidal self-injury (NSSI) are common in adolescent patients with major depressive disorder (MDD). Thus, delineating the unique characteristics of suicide attempters having adolescent MDD with NSSI is important for suicide prediction in the clinical setting. Here, we performed psychological and biochemical assessments of 130 youths having MDD with NSSI. Participants were divided into two groups according to the presence/absence of suicide attempts (SAs). Our results demonstrated that the age of suicide attempters is lower than that of non-attempters in participants having adolescent MDD with NSSI; suicide attempters had higher Barratt Impulsiveness Scale (BIS-11) impulsivity scores and lower serum CRP and cortisol levels than those having MDD with NSSI alone, suggesting levels of cortisol and CRP were inversely correlated with SAs in patients with adolescent MDD with NSSI. Furthermore, multivariate regression analysis revealed that NSSI frequency in the last month and CRP levels were suicidal ideation predictors in adolescent MDD with NSSI, which may indicate that the increased frequency of NSSI behavior is a potential risk factor for suicide. Additionally, we explored the correlation between psychological and blood biochemical indicators to distinguish suicide attempters among participants having adolescent MDD with NSSI and identified a unique correlation network that could serve as a marker for suicide attempters. Our research data further suggested a complex correlation between the psychological and behavioral indicators of impulsivity and anger. Therefore, our study findings may provide clues to identify good clinical warning signs for SA in patients with adolescent MDD with NSSI.

Theta oscillatory dynamics serving cognitive control index psychosocial distress in youth

Background

Psychosocial distress among youth is a major public health issue characterized by disruptions in cognitive control processing. Using the National Institute of Mental Health's Research Domain Criteria (RDoC) framework, we quantified multidimensional neural oscillatory markers of psychosocial distress serving cognitive control in youth.

Methods

The sample consisted of 39 peri-adolescent participants who completed the NIH Toolbox Emotion Battery (NIHTB-EB) and the Eriksen flanker task during magnetoencephalography (MEG). A psychosocial distress index was computed with exploratory factor analysis using assessments from the NIHTB-EB. MEG data were analyzed in the time-frequency domain and peak voxels from oscillatory maps depicting the neural cognitive interference effect were extracted for voxel time series analyses to identify spontaneous and oscillatory aberrations in dynamics serving cognitive control as a function of psychosocial distress. Further, we quantified the relationship between psychosocial distress and dynamic functional connectivity between regions supporting cognitive control.

Results

The continuous psychosocial distress index was strongly associated with validated measures of pediatric psychopathology. Theta-band neural cognitive interference was identified in the left dorsolateral prefrontal cortex (dlPFC) and middle cingulate cortex (MCC). Time series analyses of these regions indicated that greater psychosocial distress was associated with elevated spontaneous activity in both the dlPFC and MCC and blunted theta oscillations in the MCC. Finally, we found that stronger phase coherence between the dlPFC and MCC was associated with greater psychosocial distress.

Conclusions

Greater psychosocial distress was marked by alterations in spontaneous and oscillatory theta activity serving cognitive control, along with hyperconnectivity between the dlPFC and MCC.

Psychosocial stress, adult suicidal ideation, and the mediating effect of poor sleep quality during the COVID-19 pandemic in South Africa

OBJECTIVES

South Africa instituted one of the world's strictest lockdowns during the COVID-19 pandemic, which generated heightened conditions of psychosocial stress and posed widespread mental health risks. Despite the elevated burdens of suicidal behaviors and risk of psychiatric disease in the country, few studies have examined the impacts of psychosocial stress from the pandemic on suicidal ideation in South Africa. This study examined the association between psychosocial stress experienced under the COVID-19 pandemic and adult suicidal ideation, as well as degree to which sleep quality and duration mediated this relationship.

METHODS

An online survey assessed experiences of COVID-19 psychosocial stress, sleep quality and duration, and suicidal ideation in a sample of 189 South African adults during the second and third waves of the COVID-19 pandemic. A causal inference framework for mediation analysis was used to assess the degree to which sleep quality and duration explained the association between COVID-19 psychosocial stress and suicidal ideation.

RESULTS

Suicidal ideation was reported in 21% of adults. Adults described having moderate sleep quality and an average of 6.9 hours of sleep per night. COVID-19 psychosocial stress significantly predicted adult suicidal ideation in fully adjusted models. Sleep quality, but not sleep duration, significantly mediated the association between COVID-19 psychosocial stress and suicidal ideation, accounting for 25.9% of the total effect.

CONCLUSIONS

Poor sleep quality may play an important role in exacerbating the alarming stress-induced mental health effects of the COVID-19 pandemic. Further research is necessary to understand the underlying sleep dynamics and associated psychological and neurobiological processes that perpetuate adult suicidal ideation.

Association between insurance type and suicide-related behavior among US adults: The impact of the Affordable Care Act

This study examined the association between insurance type and suicidal ideation and attempts among adults in the United States, incorporating a comparative analysis of the pre- and post-Affordable Care Act (ACA) periods. We used a nationally representative, cross-sectional, population-based survey of individuals aged 18 years and older from the 2010-2019 National Survey on Drug Use and Health. The higher rates of suicidal ideation and attempts among Medicaid and uninsured groups compared with those with private insurance. After implementation of the ACA policy, the difference-in-differences analysis showed a significantly reduced risk of suicide in the Medicare group compared with the privately insured group, with no significant differences observed in the other groups. These findings highlight the importance of improving access to mental health services, particularly for those with lower levels of insurance coverage, such as Medicaid and Medicare.

Evaluating potential effects of distress symptoms' interventions on suicidality: Analyses of in silico scenarios

BACKGROUND

Complexity science perspectives like the network approach to psychopathology have emerged as a prominent methodological toolkit to generate novel hypotheses on complex etiologies surrounding various mental health problems and inform intervention targets. Such approach may be pivotal in advancing early intervention of suicidality among the younger generation (10-35 year-olds), the increasing burden of which needs to be reversed within a limited window of opportunity to avoid massive long-term repercussions. However, the network approach currently lends limited insight into the potential extent of proposed intervention targets' effectiveness, particularly for target outcomes in comorbid conditions.

METHODS

This paper proposes an in silico (i.e., computer-simulated) intervention approach that maps symptoms' complex interactions onto dynamic processes and analyzes their evolution. The proposed methodology is applied to investigate potential effects of changes in 1968 community-dwelling individuals' distress symptoms on their suicidal ideation. Analyses on specific subgroups were conducted. Results were also compared with centrality indices employed in typical network analyses.

RESULTS

Findings concur with symptom networks' centrality indices in suggesting that timely deactivating hopelessness among distressed individuals may be instrumental in preventing distress to develop into suicidal ideation. Additionally, however, they depict nuances beyond those provided by centrality indices, e.g., among young adults, reducing nervousness and tension may have similar effectiveness as deactivating hopeless in reducing suicidal ideation.

LIMITATIONS

Caution is warranted when generalizing findings here to the general population.

CONCLUSION

The proposed methodology may help facilitate timely agenda-setting in population mental health measures, and may also be augmented for future co-creation projects.

Whole-brain structural and functional neuroimaging of individuals who attempted suicide and people who did not: A systematic review and exploratory coordinate-based meta-analysis

Suicide is the cause of death of approximately 800,000 people a year. Despite the relevance of this behaviour, risk assessment tools rely on clinician experience and subjective ratings. Given that previous suicide attempts are the single strongest predictors of future attempts, we designed a systematic review and coordinate-based meta-analysis to demonstrate whether neuroimaging features can help distinguish individuals who attempted suicide from subjects who did not. Out of 5,659 publications from PubMed, Scopus, and Web of Science, we summarised 102 experiments and meta-analysed 23 of them. A cluster in the right superior temporal gyrus, a region implicated in emotional processing, might be functionally hyperactive in individuals who attempted suicide. No statistically significant differences in brain morphometry were evidenced. Furthermore, we used JuSpace to show that this cluster is enriched in 5-HT1A heteroreceptors in the general population. This exploratory meta-analysis provides a putative neural substrate linked to previous suicide attempts. Heterogeneity in the analytical techniques and weak or absent power analysis of the studies included in this review currently limit the applicability of the findings, the replication of which should be prioritised.

Depicting the molecular features of suicidal behavior: a review from an "omics" perspective

Background Suicide is one of the leading global causes of death. Behavior patterns from suicide ideation to completion are complex, involving multiple risk factors. Advances in technologies and large-scale bioinformatic tools are changing how we approach biomedical problems. The "omics" field may provide new knowledge about suicidal behavior to improve identification of relevant biological pathways associated with suicidal behavior. Methods We reviewed transcriptomic, proteomic, and metabolomic studies conducted in blood and post-mortem brains from individuals who experienced suicide or suicidal behavior. Omics data were combined using systems biology in silico, aiming at identifying major biological mechanisms and key molecules associated with suicide. Results Post-mortem samples of suicide completers indicate major dysregulations in pathways associated with glial cells (astrocytes and microglia), neurotransmission (GABAergic and glutamatergic systems), neuroplasticity and cell survivor, immune responses and energy homeostasis. In the periphery, studies found alterations in molecules involved in immune responses, polyamines, lipid transport, energy homeostasis, and amino and nucleic acid metabolism. Limitations We included only exploratory, non-hypothesis-driven studies; most studies only included one brain region and whole tissue analysis, and focused on suicide completers who were white males with almost none confounding factors. Conclusions We can highlight the importance of synaptic function, especially the balance between the inhibitory and excitatory synapses, and mechanisms associated with neuroplasticity, common pathways associated with psychiatric disorders. However, some of the pathways highlighted in this review, such as transcriptional factors associated with RNA splicing, formation of cortical connections, and gliogenesis, point to mechanisms that still need to be explored.

The role of polyunsaturated fatty acids in the neurobiology of major depressive disorder and suicide risk

Long-chain polyunsaturated fatty acids (LC-PUFAs) are obtained from diet or derived from essential shorter-chain fatty acids, and are crucial for brain development and functioning. Fundamentally, LC-PUFAs' neurobiological effects derive from their physicochemical characteristics, including length and double bond configuration, which differentiate LC-PUFA species and give rise to functional differences between n(omega)-3 and n-6 LC-PUFAs. LC-PUFA imbalances are implicated in psychiatric disorders, including major depression and suicide risk. Dietary intake and genetic variants in enzymes involved in biosynthesis of LC-PUFAs from shorter chain fatty acids influence LC-PUFA status. Domains impacted by LC-PUFAs include 1) cell signaling, 2) inflammation, and 3) bioenergetics. 1) As major constituents of lipid bilayers, LC-PUFAs are determinants of cell membrane properties of viscosity and order, affecting lipid rafts, which play a role in regulation of membrane-bound proteins involved in cell-cell signaling, including monoaminergic receptors and transporters. 2) The n-3:n-6 LC-PUFA balance profoundly influences inflammation. Generally, metabolic products of n-6 LC-PUFAs (eicosanoids) are pro-inflammatory, while those of n-3 LC-PUFAs (docosanoids) participate in the resolution of inflammation. Additionally, n-3 LC-PUFAs suppress microglial activation and the ensuing proinflammatory cascade. 3) N-3 LC-PUFAs in the inner mitochondrial membrane affect oxidative stress, suppressing production of and scavenging reactive oxygen species (ROS), with neuroprotective benefits. Until now, this wealth of knowledge about LC-PUFA biomechanisms has not been adequately tapped to develop translational studies of LC-PUFA clinical effects in humans. Future studies integrating neurobiological mechanisms with clinical outcomes may suggest ways to identify depressed individuals most likely to respond to n-3 LC-PUFA supplementation, and mechanistic research may generate new treatment strategies.

Relationship between biological rhythm dysregulation and suicidal ideation in patients with major depressive disorder

BACKGROUND

Although the disturbance of circadian rhythms represents a significant clinical feature of major depressive disorder (MDD), the relationship between biological rhythm disturbances and the severity of suicidal ideation in individuals with MDD remains unclear. We aimed to explore the characteristics of different biological rhythm dimensions in MDD and their association with the severity of depressive symptoms and suicidal ideation.

METHODS

A total of 50 MDD patients and 50 healthy controls were recruited and their general information was collected. The severity of depressive symptoms was assessed with the 17-item Hamilton Depression Rating Scale (HDRS17). The intensity of suicidal ideation was evaluated with the Beck Scale for Suicide Ideation (BSS). The Chinese version of the Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) scale was utilized to assess the participants' biological rhythm dysregulation. Multiple logistic regression analysis was conducted to explore the relationship between biological rhythm and the risk of MDD. Multiple linear regression analysis was performed in the MDD group to investigate the relationship between different biological rhythm dimensions and suicide ideation.

RESULTS

Significant differences were observed between the MDD group and the control group in total BRIAN score (Z=-5.41, P < 0.001) as well as scores for each dimension. After adjusting for confounding factors, multiple logistic regression analysis revealed a significant association between total BRIAN score and the presence of MDD (OR = 1.20, 95% CI = 1.10-1.29, P < 0.001), as well as between scores in different BRIAN dimensions and the presence of MDD (activity: OR = 1.47, 95% CI = 1.24-1.74, P < 0.001; sleep: OR = 1.52, 95% CI = 1.28-1.79, P < 0.001; social: OR = 1.80, 95% CI = 1.32-2.46, P < 0.001; eating pattern: OR = 1.34, 95% CI = 1.12-1.60, P = 0.001). In patients with MDD, linear regression analysis demonstrated a positive relationship between BSS scores and BRIAN eating pattern scores (β = 0.34, P = 0.022), even after adjusting for demographic factors and the severity of depression.

CONCLUSIONS

Patients with MDD exhibited significantly higher levels of dysregulation in all four biological rhythm dimensions compared to healthy controls and the degree of dysregulation was associated with the severity of depression. More importantly, dysregulation of eating pattern may increase the intensity of suicidal ideation in MDD, thus elevating the risk of suicide.

A Prospective Multicenter Longitudinal Analysis of Suicidal Ideation among Long-COVID-19 Patients

Long coronavirus disease 19 (COVID-19) is an emerging multifaceted illness with the pathological hallmarks of chronic inflammation and neuropsychiatric symptoms. These pathologies have also been implicated in developing suicidal behaviors and suicidal ideation (SI). However, research addressing suicide risk in long COVID-19 is limited. In this prospective study, we aim to characterize SI development among long-COVID-19 patients and to determine the predictive power of inflammatory markers and long-COVID-19 symptoms-including those of psychiatric origin-for SI. During this prospective, longitudinal, multicenter study, healthy subjects and long-COVID-19 patients will be recruited from the University Hospital of Geneva, Switzerland, the University of Genova, the University of Rome "La Sapienza", and the University of San Francisco. Study participants will undergo a series of clinic visits over a follow-up period of 1 year for SI assessment. Baseline and SI-onset levels of inflammatory mediators in plasma samples, along with 12 long-COVID-19 features (post-exertional malaise, fatigue, brain fog, dizziness, gastrointestinal disturbance, palpitations, changes in sexual desire/capacity, loss/change of smell/taste, thirst, chronic cough, chest pain, and abnormal movements) will be collected for SI risk analysis. The proposed enrollment period is from 15 January 2024 to 15 January 2026 with targeted recruitment of 100 participants for each study group. The anticipated findings of this study are expected to provide important insights into suicide risk among long-COVID-19 patients and determine whether inflammation and psychiatric comorbidities are involved in the development of SI in these subjects. This could pave the way to more effective evidence-based suicide prevention approaches to address this emerging public health concern.

Impulsivity and Psychiatric Diagnoses as Mediators of Suicidal Ideation and Suicide Attempts Among Veterans With Traumatic Brain Injury

OBJECTIVE

Traumatic brain injury (TBI) is a risk factor for suicide, but questions related to mechanisms remain unanswered. Impulsivity is a risk factor for suicide and is a common sequela of TBI. The authors explored the relationships between TBI and both suicidal ideation and suicide attempts and explored whether impulsivity and comorbid psychiatric diagnoses mediate these relationships.

METHODS

This cross-sectional retrospective chart review study included 164 veterans enrolled in a previous study. Sixty-nine veterans had no TBI history, and 95 had a TBI history (mild, N=44; moderate, N=13; severe, N=12; and unclear severity, N=26). To examine the associations between TBI and suicidal ideation or suicide attempts, as well as potential mediators of these relationships, chi-square tests, t tests, and logistic regression models were used.

RESULTS

Unadjusted analyses indicated that veterans with TBI were more likely to report suicidal ideation; however, in analyses controlling for mediators, this relationship was no longer significant. Among veterans with TBI, suicidal ideation was related most strongly to high impulsivity (odds ratio=15.35, 95% CI=2.43-96.79), followed by depression (odds ratio=5.73, 95% CI=2.53-12.99) and posttraumatic stress disorder (odds ratio=2.57, 95% CI=1.03-6.42). TBI was not related to suicide attempts, yet suicide attempts were related to high impulsivity (odds ratio=6.95, 95% CI=1.24-38.75) and depression (odds ratio=3.89, 95% CI=1.56-9.40).

CONCLUSIONS

These findings suggest that impulsivity, followed by psychiatric diagnoses, most strongly mediate the relationships between TBI and both suicidal ideation and suicide attempts. Impulsivity may be mechanistically related to, and serve as a future treatment target for, suicidality among veterans with TBI.

The short-term effect of ambient particulate matter on suicide death

BACKGROUND

Air pollution can cause various respiratory and neurological diseases and continuous exposure can lead to death. Previous studies have reported that particulate matter (PM) exposure increases the risk of depression, suicidal thoughts, and suicidal death; however, the results are inconsistent and limited. This study aimed to examine the relationship between short-term PM exposure and suicide deaths, as well as investigate the short-term effects of PM on suicide death within vulnerable groups based on factors such as sex, age group, suicide-related information (note, method, and cause), psychiatric disorders, and physical diseases.

METHODS

Data on a total of 28,670 suicide deaths from 2013 to 2017, provided by the Korea Foundation for Suicide Prevention, were analyzed. The study design employed a time-series analysis with a two-stage approach. In the first step, a generalized additive model combined with a distributed lag nonlinear model was used to estimate the short-term effect of PM exposure on suicide risk specific to each city. In the second step, the estimated results from each city were pooled through a meta-analysis to derive the overall effect. We determined the effects of single lag, cumulative lag, and moving average PM concentrations from days 0-7 before suicide.

RESULTS

We confirmed an association between exposure to PM10 (≤ 10 μm in diameter) and deaths due to suicide. In particular, among individuals with psychiatric disorders and those who employed non-violent suicide methods, increased exposure to PM10 was associated with a higher risk of death by suicide, with percentage changes of 5.92 (95% confidence interval [CI]: 3.95-7.92) and 11.47 (95% CI: 7.95-15.11), respectively. Furthermore, in the group with psychiatric disorders, there was an observed tendency of increasing suicide risk as PM10 levels increased up to 120 µg/m3, whereas in the group with non-violent suicide deaths, there was a pronounced trend of rapid increase in suicide risk with an increase in PM10 up to 100 µg/m3.

CONCLUSIONS

These results show an association between short-term exposure to PM and suicide. Our study adds evidence for the benefits of reducing PM in preventing diseases and improving mental health.

Integrative transcriptome- and DNA methylation analysis of brain tissue from the temporal pole in suicide decedents and their controls

Suicide rates have increased steadily world-wide over the past two decades, constituting a serious public health crisis that creates a significant burden to affected families and the society as a whole. Suicidal behavior involves a multi-factorial etiology, including psychological, social and biological factors. Since the molecular neural mechanisms of suicide remain vastly uncharacterized, we examined transcriptional- and methylation profiles of postmortem brain tissue from subjects who died from suicide as well as their neurotypical healthy controls. We analyzed temporal pole tissue from 61 subjects, largely free from antidepressant and antipsychotic medication, using RNA-sequencing and DNA-methylation profiling using an array that targets over 850,000 CpG sites. Expression of NPAS4, a key regulator of inflammation and neuroprotection, was significantly downregulated in the suicide decedent group. Moreover, we identified a total of 40 differentially methylated regions in the suicide decedent group, mapping to seven genes with inflammatory function. There was a significant association between NPAS4 DNA methylation and NPAS4 expression in the control group that was absent in the suicide decedent group, confirming its dysregulation. NPAS4 expression was significantly associated with the expression of multiple inflammatory factors in the brain tissue. Overall, gene sets and pathways closely linked to inflammation were significantly upregulated, while specific pathways linked to neuronal development were suppressed in the suicide decedent group. Excitotoxicity as well as suppressed oligodendrocyte function were also implicated in the suicide decedents. In summary, we have identified central nervous system inflammatory mechanisms that may be active during suicidal behavior, along with oligodendrocyte dysfunction and altered glutamate neurotransmission. In these processes, NPAS4 might be a master regulator, warranting further studies to validate its role as a potential biomarker or therapeutic target in suicidality.

Six Major Steps to Make Investigations of Suicide Valuable for Learning and Prevention

OBJECTIVE

The decline in suicide rates has leveled off in many countries during the last decade, suggesting that new interventions are needed in the work with suicide prevention. Learnings from investigations of suicide should contribute to the development of these new interventions. However, reviews of investigations have indicated that few new lessons have been learned. To be an effective tool, revisions of the current investigation methods are required. This review aimed to describe the problems with the current approaches to investigations of suicide as patient harm and to propose ways to move forward.

METHODS

Narrative literature review.

RESULTS

Several weaknesses in the current approaches to investigations were identified. These include failures in embracing patient and system perspectives, not addressing relevant factors, and insufficient competence of the investigation teams. Investigation methods need to encompass the progress of knowledge about suicidal behavior, suicide prevention, and patient safety.

CONCLUSIONS

There is a need for a paradigm shift in the approaches to investigations of suicide as potential patient harm to enable learning and insights valuable for healthcare improvement. Actions to support this paradigm shift include involvement of patients and families, education for investigators, multidisciplinary analysis teams with competence in and access to relevant parts across organizations, and triage of cases for extensive analyses. A new model for the investigation of suicide that support these actions should facilitate this paradigm shift.HIGHLIGHTSThere are weaknesses in the current approaches to investigations of suicide.A paradigm shift in investigations is needed to contribute to a better understanding of suicide.New knowledge of suicidal behavior, prevention, and patient safety must be applied.

Alzheimer's Disease and Suicide: An Integrative Literature Review

INTRODUCTION

Suicide has been described in patients with Alzheimer's disease. Some promising medications for treating Alzheimer's disease have had their studies suspended because they increase the risk of suicide. Understanding the correlations between suicide and Alzheimer's disease is essential in an aging world.

METHODS

A search was carried out on electronic websites (PubMed and Scielo) using the MeSH Terms "suicide" and "Alzheimer" (1986-2023). Of a total of 115 articles, 26 were included in this review.

RESULTS

Depression and the allele ε4 of Apolipoprotein (APOE4) were demonstrated to be the main risk factors for suicide in patients with Alzheimer's disease.

CONCLUSION

Adequately delineating which elderly people are vulnerable to suicide is important so that new treatments for Alzheimer's disease can be successful. This review showed a need for new studies to investigate the interface between Alzheimer's disease and suicide.

The role of substance use disorders in the transition from suicide attempt to suicide death: a record linkage study of a Swedish cohort

BACKGROUND

Suicidal behavior and substance use disorders (SUDs) are important public health concerns. Prior suicide attempts and SUDs are two of the most consistent predictors of suicide death, and clarifying the role of SUDs in the transition from suicide attempt to suicide death could inform prevention efforts.

METHODS

We used national Swedish registry data to identify individuals born 1960-1985, with an index suicide attempt in 1997-2017 (N = 74 873; 46.7% female). We assessed risk of suicide death as a function of registration for a range of individual SUDs. We further examined whether the impact of SUDs varied as a function of (i) aggregate genetic liability to suicidal behavior, or (ii) age at index suicide attempt.

RESULTS

In univariate models, risk of suicide death was higher among individuals with any SUD registration [hazard ratios (HRs) = 2.68-3.86]. In multivariate models, effects of specific SUDs were attenuated, but remained elevated for AUD (HR = 1.86 95% confidence intervals 1.68-2.05), opiates [HR = 1.58 (1.37-1.82)], sedatives [HR = 1.93 (1.70-2.18)], and multiple substances [HR = 2.09 (1.86-2.35)]. In secondary analyses, the effects of most, but not all, SUD were exacerbated by higher levels of genetic liability to suicide death, and among individuals who were younger at their index suicide attempt.

CONCLUSIONS

In the presence of a strong predictor of suicide death - a prior attempt - substantial predictive power is still attributable to SUDs. Individuals with SUDs may warrant additional suicide screening and prevention efforts, particularly in the context of a family history of suicidal behavior or early onset of suicide attempt.

Downregulated NPAS4 in multiple brain regions is associated with major depressive disorder

Major Depressive Disorder (MDD) is a commonly observed psychiatric disorder that affects more than 2% of the world population with a rising trend. However, disease-associated pathways and biomarkers are yet to be fully comprehended. In this study, we analyzed previously generated RNA-seq data across seven different brain regions from three distinct studies to identify differentially and co-expressed genes for patients with MDD. Differential gene expression (DGE) analysis revealed that NPAS4 is the only gene downregulated in three different brain regions. Furthermore, co-expressing gene modules responsible for glutamatergic signaling are negatively enriched in these regions. We used the results of both DGE and co-expression analyses to construct a novel MDD-associated pathway. In our model, we propose that disruption in glutamatergic signaling-related pathways might be associated with the downregulation of NPAS4 and many other immediate-early genes (IEGs) that control synaptic plasticity. In addition to DGE analysis, we identified the relative importance of KEGG pathways in discriminating MDD phenotype using a machine learning-based approach. We anticipate that our study will open doors to developing better therapeutic approaches targeting glutamatergic receptors in the treatment of MDD.

Resting-state network analysis of suicide attempt history in the UK Biobank

BACKGROUND

Prior research has identified altered brain structure and function in individuals at risk for self-directed violence thoughts and behaviors. However, these studies have largely utilized healthy controls and findings have been inconsistent. Thus, this study examined differences in resting-state functional network connectivity among individuals with lifetime suicide attempt(s) v. lifetime self-directed violence thoughts alone.

METHODS

Using data from the UK Biobank, this study utilized a series of linear regressions to compare individuals with lifetime suicide attempt(s) (n = 566) v. lifetime self-directed violence thoughts alone (n = 3447) on within- and between- network resting-state functional connectivity subnetworks.

RESULTS

There were no significant between-group differences for between-network, within-network, or whole-brain functional connectivity after adjusting for age, sex, ethnicity, and body mass index and performing statistical corrections for multiple comparisons. Resting-state network measures may not differentiate between individuals with lifetime suicide attempt(s) and lifetime self-directed violence thoughts alone.

CONCLUSIONS

Null findings diverge from results reported in smaller neuroimaging studies of suicide risk, but are consistent with null findings in other large-scale studies and meta-analyses. Strengths of the study include its large sample size and stringent control group. Future research on a wider array of imaging, genetic, and psychosocial risk factors can clarify relative contributions of individual and combined variables to suicide risk and inform scientific understanding of ideation-to-action framework.

Positive imagery in depressive suicidal patients: A randomized controlled trial of the effect of viewing loved ones' photos on mood states and suicidal ideation

According to research, it has been suggested that individuals who are affected by depression could potentially engage in the creation and experience emotional advantages relating to positive events directed towards the past or future, with the condition that they are provided with suitable mental imagery techniques. The main aim of this study was to assess the impact of utilizing positive imagery, specifically through the utilization of photographs featuring loved ones, on mood states and suicidal ideation among individuals diagnosed with depression and exhibiting suicidal tendencies. This randomized, double-blind, controlled crossover trial was conducted among 78 hospitalized depressive patients at three psychiatric services between April and August 2019. The patients participated in four individual picture-viewing sessions on four consecutive days. The four categories of pictures were included: loved ones, neutral faces of strangers, natural landscapes, and optical illusions. Directly prior to and immediately following the observation of the visual stimuli (photographs), the Brunel Mood Scale (BRUMS) and the Beck Scale for Suicide Ideation (BSSI) were completed by the patients. Repeated measures ANOVAs conducted in this study revealed a significant main effect of time on ratings of tension, depression, fatigue, vigor, calmness, and happiness (P values < 0.001). Additionally, statistically significant interactions were identified between picture category and time in relation to the variables of tension, depression, fatigue, vigor, calmness, and happiness (P values < 0.001). The analysis did not reveal a significant main effect of time on ratings of anger, confusion, and suicidal ideation (P values > 0.05). Likewise, the interaction between picture category and time did not yield significant results for the variables of anger, confusion, and suicidal ideation (P values > 0.05). The positive imagery procedure using the presentation of loved ones' photos showed beneficial effects on the mood states of depressed patients. The findings of this study suggest that incorporating a greater emphasis on positive imagery within the context of clinical depression may offer potential advantages. This highlights the potential for novel opportunities in the treatment of depression.

Trial registration

The study has been registered in the Iranian Registry of Clinical Trials (registration number: IRCT20180808040744N1; first registration date: December 22, 2018; website: https://en.irct.ir/trial/33186).

Diagnosis of Major Depressive Disorder Using Machine Learning Based on Multisequence MRI Neuroimaging Features

BACKGROUND

Previous studies have found qualitative structural and functional brain changes in major depressive disorder (MDD) patients. However, most studies ignored the complementarity of multisequence MRI neuroimaging features and cannot determine accurate biomarkers.

PURPOSE

To evaluate machine-learning models combined with multisequence MRI neuroimaging features to diagnose patients with MDD.

STUDY TYPE

Prospective.

SUBJECTS

A training cohort including 111 patients and 90 healthy controls (HCs) and a test cohort including 28 patients and 22 HCs.

FIELD STRENGTH/SEQUENCE

A 3.0 T/T1-weighted imaging, resting-state functional MRI with echo-planar sequence, and single-shot echo-planar diffusion tensor imaging.

ASSESSMENT

Recruitment and integration were used to reflect the dynamic changes of functional networks, while gray matter volume and fractional anisotropy were used to reflect the changes in the morphological and anatomical network. We then fused features with significant differences in functional, morphological, and anatomical networks to evaluate a random forest (RF) classifier to diagnose patients with MDD. Furthermore, a support vector machine (SVM) classifier was used to verify the stability of neuroimaging features. Linear regression analyses were conducted to investigate the relationships among multisequence neuroimaging features and the suicide risk of patients.

STATISTICAL TESTS

The comparison of functional network attributes between patients and controls by two-sample t-test. Network-based statistical analysis was used to identify structural and anatomical connectivity changes between MDD and HCs. The performance of the model was evaluated by receiver operating characteristic (ROC) curves.

RESULTS

The performance of the RF model integrating multisequence neuroimaging features in the diagnosis of depression was significantly improved, with an AUC of 93.6%. In addition, we found that multisequence neuroimaging features could accurately predict suicide risk in patients with MDD (r = 0.691).

DATA CONCLUSION

The RF model fusing functional, morphological, and anatomical network features performed well in diagnosing patients with MDD and provided important insights into the pathological mechanisms of MDD.

EVIDENCE LEVEL

1.

TECHNICAL EFFICACY

Stage 2.

Protective factors of suicidal behaviors in children and adolescents/young adults: A literature review

BACKGROUND

Suicidal behaviors present a public health challenge in children and adolescents. Although the risk factors have long been well documented, protective factors have only been documented for a few years, and there has not been a literature review concerning the suicidal behaviors of children and adolescents since 2006.

METHODS

Relevant articles were collected using the Medline/PubMed, Web of Science, and ScienceDirect databases. Studies meeting the following inclusion criteria were included: age of participants from 6 to 19 years, qualitative and quantitative cohort or case-control studies, multivariate analysis studies, and studies with significant results for at least one protective factor. The methodology used in this review is based on the PRISMA criteria.

RESULTS

A total of 26 studies were included in this review, which highlights various individual and environmental protective factors. The results were too heterogeneous to perform a meta-analysis, and therefore the discussion is in the form of a narrative summary. High-quality relationships with family and in the school environment were the most frequently found protective factors. The presence of positive links with peers, with other adults, and with the culture of origin was also noted. On an individual level, self-esteem, emotional intelligence, and particular coping abilities were found to be the most important protective factors.

CONCLUSION

There are numerous important protective factors for suicidal behaviors in children and adolescents and also for adapting care to their needs. A future challenge will be to determine the best protective factors to be consolidated or strengthened using self-assessment tools that are already in use or being developed.

Allostatic load in early adolescence: gene / environment contributions and relevance for mental health

Background

Allostatic load is the cumulative "wear and tear" on the body due to chronic adversity. We aimed to test poly-environmental (exposomic) and polygenic contributions to allostatic load and their combined contribution to early adolescent mental health.

Methods

We analyzed data on N = 5,035 diverse youth (mean age 12) from the Adolescent Brain Cognitive Development Study (ABCD). Using dimensionality reduction method, we calculated and overall allostatic load score (AL) using body mass index [BMI], waist circumference, blood pressure, blood glycemia, blood cholesterol, and salivary DHEA. Childhood exposomic risk was quantified using multi-level environmental exposures before age 11. Genetic risk was quantified using polygenic risk scores (PRS) for metabolic system susceptibility (type 2 diabetes [T2D]) and stress-related psychiatric disease (major depressive disorder [MDD]). We used linear mixed effects models to test main, additive, and interactive effects of exposomic and polygenic risk (independent variables) on AL (dependent variable). Mediation models tested the mediating role of AL on the pathway from exposomic and polygenic risk to youth mental health. Models adjusted for demographics and genetic principal components.

Results

We observed disparities in AL with non-Hispanic White youth having significantly lower AL compared to Hispanic and Non-Hispanic Black youth. In the diverse sample, childhood exposomic burden was associated with AL in adolescence (beta=0.25, 95%CI 0.22-0.29, P<.001). In European ancestry participants (n=2,928), polygenic risk of both T2D and depression was associated with AL (T2D-PRS beta=0.11, 95%CI 0.07-0.14, P<.001; MDD-PRS beta=0.05, 95%CI 0.02-0.09, P=.003). Both polygenic scores showed significant interaction with exposomic risk such that, with greater polygenic risk, the association between exposome and AL was stronger. AL partly mediated the pathway to youth mental health from exposomic risk and from MDD-PRS, and fully mediated the pathway from T2D-PRS.

Conclusions

AL can be quantified in youth using anthropometric and biological measures and is mapped to exposomic and polygenic risk. Main and interactive environmental and genetic effects support a diathesis-stress model. Findings suggest that both environmental and genetic risk be considered when modeling stress-related health conditions.

Child maltreatment and youth suicide risk: A developmental conceptual model and implications for suicide prevention

Experiences of child abuse and neglect are risk factors for youth suicidal thoughts and behaviors. Accordingly, suicide risk may emerge as a developmental process that is heavily influenced by the rearing environment. We argue that a developmental, theoretical framework is needed to guide future research on child maltreatment and youth (i.e., adolescent and emerging adult) suicide, and to subsequently inform suicide prevention efforts. We propose a developmental model that integrates principles of developmental psychopathology and current theories of suicide to explain the association between child maltreatment and youth suicide risk. This model bears significant implications for future research on child maltreatment and youth suicide risk, and for suicide prevention efforts that target youth with child maltreatment experiences.

The relationships between anxiety and suicidal ideation and between depression and suicidal ideation among Chinese college students: A network analysis

Background

Suicide is a worldwide public health problem. Evidence from previous studies has confirmed the relationship among anxiety, depression and suicidal ideation. However, the complex psychopathological pathways between anxiety and suicidal ideation and between depression and suicidal ideation require further study.

Methods

A total of 505 college students from Shanghai during COVID-19 pandemic were investigated in an online study. Anxiety, depression and suicidal ideation of the participants were investigated. R software was used to construct the anxiety-suicidal ideation and depression-suicidal ideation networks and to evaluate the bridge expected influences.

Results

The anxiety-suicidal ideation network had 28 cross-community edges, the strongest one was A7 "Afraid something will happen"-S7 "Unable to solve personal problem"; A5 "Restlessness" and S3 "Hopelessness and suicide thoughts" had the highest bridge expected influences. The depression-suicidal ideation network had 36 cross-community edges, and the strongest one was D9 "Thoughts of death"-S5 "Unable to accomplish something important"; D9 "Thoughts of death" and S3 "Hopelessness and suicide thoughts" had the highest bridge expected influences.

Conclusion

Intricate psychopathological pathways exist between anxiety and suicidal ideation and between depression and suicidal ideation. "Restlessness", "Thoughts of death" and "Hopelessness and suicide thoughts" are considered targets for suicidal ideation interventions. The present study enriches the theory of symptoms and mental disorders and provides a reliable reference for the intervention practice of suicidal ideation.

A Systematic Review of MRI Studies and the "Emotional paiN and social Disconnect (END)" Brain Model of Suicidal Behavior in Youth

Introduction

Risk of suicidal ideation and suicidal behaviors greatly increases during adolescence, and rates have risen dramatically over the past two decades. However, few risk factors or biomarkers predictive of suicidal ideation or attempted suicide have been identified in adolescents. Neuroimaging correlates hold potential for early identification of adolescents at increased risk of suicidality and risk stratification for those at high risk of suicide attempt.

Methods

In this systematic review, we evaluated neural regions and networks associated with suicidal ideation and suicide attempt in adolescents derived from magnetic resonance imaging (MRI) studies. A total of 28 articles were included in this review.

Results

After descriptively synthesizing the literature, we propose the Emotional paiN and social Disconnect (END) model of adolescent suicidality and present two key neural circuits: (1) the emotional/mental pain circuit and (2) the social disconnect/distortion circuit. In the END model, the emotional pain circuit-consisting of the cerebellum, amygdala, and hippocampus-shows similar aberrations in adolescents with suicidal ideation as in those with a history of a suicide attempt (but to a smaller degree). The social disconnect circuit is unique to adolescent suicide attempters and includes the lateral orbitofrontal cortex (OFC), the temporal gyri, and the connections between them.

Conclusion

Our proposed END brain model of suicidal behavior in youth, if confirmed by future prospective studies, can have implications for clinical goals of early detection, risk stratification, and intervention development. Treatments that target emotional pain and social disconnect may be ideal interventions for reducing suicidality in adolescents.

Mediation effect of anxious attachment on relationship between childhood trauma and suicidal ideation sensitive to psychological pain levels

BACKGROUND

Childhood trauma (CT), depression, and psychological pain are known predictors of suicidal ideation. Recent literature additionally highlights the importance of the attachment system.

METHODS

We aimed to predict suicidal ideation through CT, attachment, and psychological and social pain by using mediation models aiming to predict suicidal ideation through CT (predictor) and attachment (mediator). In the same models, we introduced psychological or social pain as a moderator of the relationship between attachment, CT, and suicidal ideation. We included 161 depressed patients and assessed depression, attachment, CT, suicidal ideation, psychological pain, and social pain.

RESULTS

We found (1) a complete mediating effect of anxious attachment (a2b2 = 0.0035, CI95% = [0.0010; 0.0069]) on the relationship between CT on suicidal ideation, and (2) a significant complete conditional mediating effect of anxious attachment and psychological pain (index of moderated mediation VAS: 0.0014; CI95% = [0.0002; 0.0032]) but not social pain on the relationship between CT and suicidal ideation. Both models were controlled for history of suicidal attempt, depression severity, and sex.

CONCLUSIONS

Our results suggest a developmental profile of suicidal ideation in mood disorder that is characterized by the presence of CT and insecure attachment, especially anxious attachment, that is sensitive to experiences of psychological pain. Nevertheless, we cannot conclude that avoidantly attached individuals do not present the same mechanism, as they may not disclose those ideas.

Relationship of stress-reactive cortisol to suicidal intent of prior attempts in major depression

Higher intent suicide attempts carry elevated risk of future suicidal behavior. Abnormal functioning of the hypothalamic-pituitary-adrenal (HPA) axis is both linked to nonfatal suicidal behavior and suicide deaths in major depressive disorder. Few studies, however, have identified biological markers of a high-intent suicidal subgroup. We examined HPA axis output and reactivity to the Trier Social Stress Test (TSST) via salivary cortisol in depressed individuals (N=68) with a suicide attempt (SA) history. A median split of higher and lower suicidal intent scores was used to define groups. Individuals with high intent SA had attenuated total cortisol output (AUCg), F(1,60)=10.04, SE=5.095, p=.003, and lower HPA-axis stress responsivity to the TSST (AUCi), F(1,60)=4.50, SE=4.604, p=.039, compared with the low intent SA group. The high intent group also reported more pronounced negative affect than the low intent group (F[1,61]=6.413, SE=10.55, p=.014) both at baseline (meandiff=22.32, p=.038) and in response to the stressor task (meandiff=37.62, p=.003). Vulnerability to suicidal behavior in high-intent individuals may be related to the combined profile of impaired physiological responses to stress and greater negative affectivity. This clinical and biologic subgroup may benefit from targeted suicide prevention interventions.

Prenatal Stress Exposure Amplifies Effect of Maternal Suicidal Ideation on Early Childhood Behavioral Trajectories

The in utero environment influences fetal development and may predispose to disease later in life. This study examines whether maternal suicidal ideation during pregnancy is associated with children's behavioral trajectories across early childhood, and whether prenatal maternal traumatic stress accelerates the trajectories. The study included mother-child dyads (N = 331, 51.1% boys) from the longitudinal Stress In Pregnancy study; 31.1% (n = 103) mothers were Exposed to Superstorm Sandy. During their second trimester, 12.4% (n = 41) women reported suicidal ideation during pregnancy. Mothers completed the Behavior Assessment Scale for Children-2 annually from ages 2- to 6-years-old to assess multiple behavioral domains. Hierarchical linear modeling estimated within-person longitudinal trajectories of clinical behaviors, and between-person effects of maternal suicidal ideation and disaster-related stress in utero on changes in child behavior. For children exposed to both risks, Atypical behaviors (i.e., unusual behaviors, social disconnection) increased linearly across early childhood. Exposure to Superstorm Sandy and maternal suicidal ideation were independently associated with non-linear increases in Anxiety severity and maternal suicidal ideation during pregnancy was associated with a linear increase in Attention problems across early childhood. Maternal suicidal ideation during pregnancy is associated with increased risk for a range of behavioral and emotional difficulties in early childhood and the trajectory of atypical behaviors was amplified by disaster-related traumatic stress. Findings highlight the need for health professionals to screen for suicidal ideation among their pregnant patients. Pregnant women who experience severe stress may require additional monitoring and support to reduce risk for poorer early childhood outcomes.

Brain serotonin 1A receptor binding: relationship to peripheral blood DNA methylation, recent life stress and childhood adversity in unmedicated major depression

BACKGROUND

Childhood and lifetime adversity may reduce brain serotonergic (5-HT) neurotransmission by epigenetic mechanisms.

AIMS

We tested the relationships of childhood adversity and recent stress to serotonin 1A (5-HT1A) receptor genotype, DNA methylation of this gene in peripheral blood monocytes and in vivo 5-HT1A receptor binding potential (BPF) determined by positron emission tomography (PET) in 13 a priori brain regions, in participants with major depressive disorder (MDD) and healthy volunteers (controls).

METHOD

Medication-free participants with MDD (n = 192: 110 female, 81 male, 1 other) and controls (n = 88: 48 female, 40 male) were interviewed about childhood adversity and recent stressors and genotyped for rs6295. DNA methylation was assayed at three upstream promoter sites (-1019, -1007, -681) of the 5-HT1A receptor gene. A subgroup (n = 119) had regional brain 5-HT1A receptor BPF quantified by PET. Multi-predictor models were used to test associations between diagnosis, recent stress, childhood adversity, genotype, methylation and BPF.

RESULTS

Recent stress correlated positively with blood monocyte methylation at the -681 CpG site, adjusted for diagnosis, and had positive and region-specific correlations with 5-HT1A BPF in participants with MDD, but not in controls. In participants with MDD, but not in controls, methylation at the -1007 CpG site had positive and region-specific correlations with binding potential. Childhood adversity was not associated with methylation or BPF in participants with MDD.

CONCLUSIONS

These findings support a model in which recent stress increases 5-HT1A receptor binding, via methylation of promoter sites, thus affecting MDD psychopathology.

Risk factors of suicidal spectrum behaviors in adults and adolescents with attention-deficit / hyperactivity disorder - a systematic review

INTRODUCTION

Adolescents and adults with attention-deficit/hyperactivity disorder (ADHD) are at increased risk of suicidal spectrum behaviors (SSBs). However, there is limited knowledge about risk factors triggering SSBs in this group of people.

OBJECTIVE

To explore published literature concerning factors that may increase the risk of SSBs in adults and adolescents with ADHD.

METHODS

A systematic literature search following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted on 22nd of February 2022 using the Ovid MEDLINE and Web of Science databases. Three categories of search terms were used: (1) self-harm, self-injury, self-mutilation, suicide, self-poisoning; (2) adults, adolescents; and (3) attention-deficit hyperactivity disorder/ADHD. Studies with data concerning mediating factors of SSBs in relation to a clinical diagnosis of ADHD in participants above 16 years of age were included.

RESULTS

The literature search identified 604 articles, of which 40 were included in the final study selection. Factors found to increase the likelihood of SSBs included ADHD symptom severity and persistence, female gender, family history of ADHD, childhood and parental influences, and social functioning. Even when adjusting for psychiatric comorbidities, most studies showed that adults and adolescents with ADHD have an elevated risk of SSBs.

CONCLUSION

This systematic review has documented that several demographic and clinical features are associated with an increased risk of SSBs in adolescents and adults with ADHD. Notably, ADHD emerges as an independent risk factor for SSBs. This information ought to have clinical implications in terms of screening and suicide prevention strategies. Further longitudinal studies are needed to investigate the outcome of preventive strategies in individuals along the full spectrum of ADHD symptom severity.

Hill L, Kline A, Stanley BH, Interian A. Improving the prospective prediction of a near-term suicide attempt in veterans at risk for suicide, using a go/no-go task

BACKGROUND

Neurocognitive testing may advance the goal of predicting near-term suicide risk. The current study examined whether performance on a Go/No-go (GNG) task, and computational modeling to extract latent cognitive variables, could enhance prediction of suicide attempts within next 90 days, among individuals at high-risk for suicide.

METHOD

136 Veterans at high-risk for suicide previously completed a computer-based GNG task requiring rapid responding (Go) to target stimuli, while withholding responses (No-go) to infrequent foil stimuli; behavioral variables included false alarms to foils (failure to inhibit) and missed responses to targets. We conducted a secondary analysis of these data, with outcomes defined as actual suicide attempt (ASA), other suicide-related event (OtherSE) such as interrupted/aborted attempt or preparatory behavior, or neither (noSE), within 90-days after GNG testing, to examine whether GNG variables could improve ASA prediction over standard clinical variables. A computational model (linear ballistic accumulator, LBA) was also applied, to elucidate cognitive mechanisms underlying group differences.

RESULTS

On GNG, increased miss rate selectively predicted ASA, while increased false alarm rate predicted OtherSE (without ASA) within the 90-day follow-up window. In LBA modeling, ASA (but not OtherSE) was associated with decreases in decisional efficiency to targets, suggesting differences in the evidence accumulation process were specifically associated with upcoming ASA.

CONCLUSIONS

These findings suggest that GNG may improve prediction of near-term suicide risk, with distinct behavioral patterns in those who will attempt suicide within the next 90 days. Computational modeling suggests qualitative differences in cognition in individuals at near-term risk of suicide attempt.

Neural Reactivity to Social Punishment Predicts Future Engagement in Nonsuicidal Self-injury Among Peer-Rejected Adolescents

BACKGROUND

Rates of nonsuicidal self-injury (NSSI) increase dramatically in adolescence. Affective reactivity and adverse social experiences have been linked to NSSI, but less is known about whether these factors may separately or interactively predict NSSI, especially longitudinally. This study combined functional magnetic resonance imaging and a sociometric measure to test whether a combination of neural (e.g., amygdala) reactivity to social punishment and peer-nominated peer acceptance/rejection predicts NSSI longitudinally in adolescence. Amygdala reactivity was examined as a potential neural marker of affective reactivity to social punishment, which may heighten NSSI risk in contexts of social adversity.

METHODS

One hundred twenty-five adolescents (63 female) completed a social incentive delay task during neuroimaging and school-based peer nominations to measure peer acceptance/rejection. NSSI engagement was assessed at baseline and 1-year follow-up.

RESULTS

Greater amygdala reactivity to social punishment predicted greater NSSI engagement 1 year later among adolescents with high peer rejection. This effect for the amygdala was specific to social punishment (vs. reward) and held when controlling for biological sex and pubertal development. Exploratory analyses found that ventral striatum reactivity to social reward and punishment similarly interacted with peer rejection to predict NSSI but that amygdala connectivity with salience network regions did not.

CONCLUSIONS

Amygdala reactivity to social punishment, in combination with high peer rejection, may increase NSSI risk in adolescence, possibly via heightened affective reactivity to adverse social experiences. Objective measures of neurobiological and social risk factors may improve prediction of NSSI, while therapeutic approaches that target affective reactivity and increase prosocial skills may protect against NSSI in adolescence.

Temperament and adolescent suicide attempts: a case-control study with multi-ethnic Asian adolescents

BACKGROUND

Suicide is the leading cause of death for adolescents in several parts of Asia, including Singapore. This study examines the relationship between temperament and youth suicide attempts in a sample of multi-ethnic Singaporean adolescents.

METHODS

A case-control design compared 60 adolescents (Mage = 16.40, SDage = 2.00) with a recent suicide attempt (i.e., past 6 months) with 58 adolescents (Mage = 16.00, SDage = 1.68) without any history of suicide attempts. Presence of suicide attempts was established using the semi-structured interviewer-administered Columbia Suicide Severity Rating Scale. Participants also completed self-report measures on temperament traits, psychiatric diagnoses, stressful life events, and perceived parental rejection in an interview-based format.

RESULTS

Psychiatric comorbidity, recent stressful life events, perceived parental rejection, and all five "difficult temperament" traits, were significantly overrepresented among adolescent cases relative to healthy controls. Adjusted logistic regression models revealed significant associations between suicide attempt, MDD comorbidity (OR: 10.7, 95% Cl: (2.24-51.39)), "negative mood" trait (OR: 1.12-1.18, 95% Cl: (1.00-1.27)), and the interaction term of "positive mood" and "high adaptability" traits (OR: 0.943 - 0.955, 95% Cl: (0.900 - 0.986)). Specifically, "positive mood" predicted lower likelihood of a suicide attempt when "adaptability" was high (OR: 0.335 - 0.342, 95% Cl: (0.186 - 0.500)) but not low (OR: 0.968 - 0.993, 95% Cl: (0.797 - 1.31)).

CONCLUSION

Temperament screening may be important to identify adolescents at higher or lower risk of suicide at an early stage. More longitudinal and neurobiological research converging on these temperament findings will be helpful in ascertaining temperament screening as an effective suicide prevention methodology for adolescents.

Effects of digital cognitive behavioral therapy for depression on suicidal thoughts and behavior: Protocol for a systematic review and meta-analysis of individual participant data

INTRODUCTION

Digital cognitive behavioral therapy (i-CBT) interventions for the treatment of depression have been extensively studied and shown to be effective in the reduction of depressive symptoms. However, little is known about their effects on suicidal thoughts and behaviors (STB). Information on the impact of digital interventions on STB are essential for patients' safety because most digital interventions are self-help interventions without direct support options in case of a suicidal crisis. Therefore, we aim to conduct a meta-analysis of individual participant data (IPDMA) to investigate the effects of i-CBT interventions for depression on STB and to explore potential effect moderators.

METHODS

Data will be retrieved from an established and annually updated IPD database of randomized controlled trials investigating the effectiveness of i-CBT interventions for depression in adults and adolescents. We will conduct a one-stage and a two-stage IPDMA on the effects of these interventions on STB. All types of control conditions are eligible. STB can be measured using specific scales (e.g., Beck scale suicide, BSS) or single items from depression scales (e.g., item 9 of the PHQ-9) or standardized clinical interviews. Multilevel linear regression will be used for specific scales, and multilevel logistic regression will be used for treatment response or deterioration, operationalized as a change in score by at least one quartile from baseline. Exploratory moderator analyses will be conducted at participant, study, and intervention level. Two independent reviewers will assess the risk of bias using the Cochrane Risk of Bias Tool 2.

CONCLUSION

This IPDMA will harness the available data to assess the effects (response and deterioration) of i-CBT interventions for depression interventions on STB. Information about changes in STB is essential to estimate patients' safety when engaging in digital treatment formats.

TRIAL REGISTRATION

We will pre-register this study with the open science framework after article acceptance to ensure consistency between online registration and the published trial protocol.

Gene Expression Analysis in Postmortem Brains from Individuals Who Died by Suicide: A Systematic Review

Around the world, more the 700,000 individuals die by suicide every year. It is necessary to understand the mechanisms associated with suicidal behavior. Recently, an increase in gene expression studies has been in development. Through a systematic review, we aimed to find a candidate gene in gene expression studies on postmortem brains of suicide completers. Databases were systematically searched for published studies. We performed an online search using PubMed, Scopus and Web of Science databases to search studies up until May 2023. The terms included were "gene expression", "expressed genes", "microarray", "qRT-PCR", "brain samples" and "suicide". Our systematic review included 59 studies covering the analysis of 1450 brain tissues from individuals who died by suicide. The majority of gene expression profiles were obtained of the prefrontal cortex, anterior cingulate cortex, dorsolateral prefrontal cortex, ventral prefrontal cortex and orbital frontal cortex area. The most studied mRNAs came of genes in glutamate, γ-amino-butyric acid and polyamine systems. mRNAs of genes in the brain-derived neurotrophic factor, tropomyosin-related kinase B (TrkB), HPA axis and chemokine family were also studied. On the other hand, psychiatric comorbidities indicate that suicide by violent death can alter the profile of mRNA expression.