Pilot randomized clinical trial of an SSRI vs bupropion: effects on suicidal behavior, ideation, and mood in major depression

Gender-specific factors of suicidal ideation among high school students in Yunnan province, China: A machine learning approach

BACKGROUND

Suicidal ideation (SI) assumes a pivotal role in predicting suicidal behaviors. The incidence of SI among high (junior and senior) school students is significantly higher than that of other age groups. The aim of this study is to explore the gender differences in SI among high school students in Yunnan Province.

METHOD

A total of 6180 students in grades 7-12 in Yunnan province, China from May 2021 to May 2022 participated in this survey. Univariate analysis was employed to describe the influencing factors of male and female students' SI. Subsequently, data were stratified by gender. Adopting machine learning technique, including Least Absolute Shrinkage and Selection Operator (Lasso) and Boruta algorithm, and logistic regression model to estimate the direction and effect magnitude of the influencing factors.

RESULTS

The prevalence of SI was significantly higher for females (31.34 %) than males (16.73 %). The logistic regression model was established using the variables screened by Boruta algorithm, indicated that anxiety, depression, suffering emotion abuse or emotion neglect in childhood, non-suicidal self-injury, evening chronotype are common risk factors for SI in male and female students. Notably, female students who exhibited aggressive behavior, have experienced bullying, and were in the junior high school learning stage were more likely to report SI than their male counterparts.

CONCLUSIONS

Females showed more vulnerability to SI than males especially among females in junior high school, reporting aggressive behavior and bullying experiences. Tailored prevention strategies, informed by these gender-related distinctions, should be developed and implemented.

Transcriptional Patterns of Brain Structural Covariance Network Abnormalities Associated With Suicidal Thoughts and Behaviors in Major Depressive Disorder

BACKGROUND

Although brain structural covariance network (SCN) abnormalities have been associated with suicidal thoughts and behaviors (STBs) in individuals with major depressive disorder (MDD), previous studies have reported inconsistent findings based on small sample sizes, and underlying transcriptional patterns remain poorly understood.

METHODS

Using a multicenter magnetic resonance imaging dataset including 218 MDD patients with STBs, 230 MDD patients without STBs, and 263 healthy control participants, we established individualized SCNs based on regional morphometric measures and assessed network topological metrics using graph theoretical analysis. Machine learning methods were applied to explore and compare the diagnostic value of morphometric and topological features in identifying MDD and STBs at the individual level. Brainwide relationships between STBs-related connectomic alterations and gene expression were examined using partial least squares regression.

RESULTS

Group comparisons revealed that SCN topological deficits associated with STBs were identified in the prefrontal, anterior cingulate, and lateral temporal cortices. Combining morphometric and topological features allowed for individual-level characterization of MDD and STBs. Topological features made a greater contribution to distinguishing between patients with and without STBs. STBs-related connectomic alterations were spatially correlated with the expression of genes enriched for cellular metabolism and synaptic signaling.

CONCLUSIONS

These findings revealed robust brain structural deficits at the network level, highlighting the importance of SCN topological measures in characterizing individual suicidality and demonstrating its linkage to molecular function and cell types, providing novel insights into the neurobiological underpinnings and potential markers for prediction and prevention of suicide.

Effects of selective serotonin reuptake inhibitors (SSRIs) on suicide: A network meta-analysis of double-blind randomized trials

The relationship between the use of selective serotonin reuptake inhibitors (SSRIs) and suicide risk in patients with mental disorders remains controversial. We conducted a network meta-analysis to examine the effects of SSRIs on suicide risk in patients with mental disorders. A comprehensive search was conducted across PubMed, Web of Science, PsycINFO, CENTRAL, Wanfang Database, and China National Knowledge Infrastructure for articles published until December 19, 2023. The main outcomes were suicidal ideation and instances of suicidal behavior. We included 29 double-blind randomized trials in our analysis. The findings suggest that SSRIs primarily offer short-term protection against suicidal ideation. By week 2, paroxetine, fluoxetine, escitalopram, and non-SSRI treatments were linked to a decreased suicide risk compared with a placebo, with the exception of sertraline. This protective effect was diminished by week 8. In contrast, studies on instances of suicidal behavior from weeks 1 to 10 found no significant difference in efficacy between SSRIs, non-SSRIs, and placebo. These results indicate that SSRIs may offer short-term protection against suicidal ideation. However, their long-term effectiveness in mitigating suicidal ideation and preventing suicidal behaviors is limited.

Risk of suicide attempts and intentional self-harm on alprazolam

BACKGROUND

From 2000-2021, U.S. suicide deaths have risen 36 %. Identification of pharmacological agents associated with increased suicide risk and safer alternatives may help reduce this trend.

METHODS

An exposure-only within-subject time-to-event pharmacoepidemiologic study of the dynamic association between alprazolam treatment and suicide attempts over 2-years. Parallel analyses were conducted for diazepam, lorazepam and buspirone. Data for 2,495,520 patients were obtained from U.S. private insurance medical claims MarketScan from 2010 to 2019.

FINDINGS

Alprazolam was associated with over a doubling of risk of suicide attempts (HR=2.21, 95 % CI=2.06,2.38). A duration-response analysis for the modal dose (0.5 mg) revealed a 5 % increase in suicidal events per additional month of treatment (HR=1.05, 95 % CI=1.04,1.07). Parallel analyses with long-acting (diazepam) and short-acting (lorazepam), found similar associations (diazepam HR=2.87, 95 % CI=2.56,3.21; lorazepam HR=1.83, 95 % CI=1.69,2.00), whereas the non-benzodiazepine anxiolytic, buspirone, showed significantly less risk (HR=1.25, 95 % CI=1.13,1.38), and no increased risk in patients with an attempt history (HR=1.05, 95 % CI=0.70,1.59).

INTERPRETATION

This study confirmed an earlier signal linking alprazolam to increased suicide attempt risk. The increased risk extends to benzodiazepines in general, regardless of half-life and risk of withdrawal seizure. Buspirone appears to be a safer treatment than benzodiazepines, particularly in patients at increased risk for suicide.

Integrative Analyses of scRNA-seq, Bulk mRNA-seq, and DNA Methylation Profiling in Depressed Suicide Brain Tissues

BACKGROUND

Suicidal behaviors have become a serious public health concern globally due to the economic and human cost of suicidal behavior to individuals, families, communities, and society. However, the underlying etiology and biological mechanism of suicidal behavior remains poorly understood.

METHODS

We collected different single omic data, including single-cell RNA sequencing (scRNA-seq), bulk mRNA-seq, DNA methylation microarrays from the cortex of Major Depressive Disorder (MDD) in suicide subjects' studies, as well as fluoxetine-treated rats brains. We matched subject IDs that overlapped between the transcriptome dataset and the methylation dataset. The differential expression genes and differentially methylated regions were calculated with a 2-group comparison analysis. Cross-omics analysis was performed to calculate the correlation between the methylated and transcript levels of differentially methylated CpG sites and mapped transcripts. Additionally, we performed a deconvolution analysis for bulk mRNA-seq and DNA methylation profiling with scRNA-seq as the reference profiles.

RESULTS

Difference in cell type proportions among 7 cell types. Meanwhile, our analysis of single-cell sequence from the antidepressant-treated rats found that drug-specific differential expression genes were enriched into biological pathways, including ion channels and glutamatergic receptors.

CONCLUSIONS

This study identified some important dysregulated genes influenced by DNA methylation in 2 brain regions of depression and suicide patients. Interestingly, we found that oligodendrocyte precursor cells (OPCs) have the most contributors for cell-type proportions related to differential expression genes and methylated sites in suicidal behavior.

Shared and specific neurobiology in bipolar disorder and unipolar disorder: Evidence based on the connectome gradient and a transcriptome-connectome association study

BACKGROUND

Distinguishing bipolar disorder (BD) and unipolar disorder (UD) remains challenging. To identify the common and diagnosis-specific neuropathological alterations and their potential molecular mechanisms in patients with UD and BD (with a current depressive episode).

METHODS

Resting-state functional magnetic resonance imaging was obtained from 279 participants (95 BD patients, 107 UD patients and 77 health controls). Connectome gradients analysis was performed to explore the shared and diagnosis-specific gradient alterations in BD and UD. The Allen Human Brain Atlas data was used to explore the potential gene mechanisms of the gradient alterations.

RESULTS

BD and UD had shared hierarchical disorganisation, including downgrading and contraction from the unimodal sensory networks (vision and sensorimotor) to the transmodal cognitive networks (limbic, frontoparietal, dorsal attention, and default) (all P < 0.05, FDR corrected) in gradient 1 and gradient 2. The BD patients had specific connectome gradient dysfunction in the subcortical network. Moreover, the hierarchical disorganisation was closely correlated with profiles of gene expression specific to the neuroglial cells in the prefrontal cortex in BD and UD, while the most correlated gene ontology biological processes and function were concentrated in synaptic signalling, calcium ion binding, and transmembrane transporter activity.

CONCLUSION

These findings reveal the shared and diagnosis-specific neurobiological mechanism underlying BD and UD patients, which advances our understanding of the neuromechanisms of these disorders.

Cortical hierarchy disorganization in major depressive disorder and its association with suicidality

Objectives

To explore the suicide risk-specific disruption of cortical hierarchy in major depressive disorder (MDD) patients with diverse suicide risks.

Methods

Ninety-two MDD patients with diverse suicide risks and 38 matched controls underwent resting-state functional MRI. Connectome gradient analysis and stepwise functional connectivity (SFC) analysis were used to characterize the suicide risk-specific alterations of cortical hierarchy in MDD patients.

Results

Relative to controls, patients with suicide attempts (SA) had a prominent compression from the sensorimotor system; patients with suicide ideations (SI) had a prominent compression from the higher-level systems; non-suicide patients had a compression from both the sensorimotor system and higher-level systems, although it was less prominent relative to SA and SI patients. SFC analysis further validated this depolarization phenomenon.

Conclusion

This study revealed MDD patients had suicide risk-specific disruptions of cortical hierarchy, which advance our understanding of the neuromechanisms of suicidality in MDD patients.

Existing and Novel Biological Therapeutics in Suicide Prevention

We summarize outcomes for several pharmacologic and neurostimulatory approaches that have been considered potential treatments to reduce suicide risk, namely, by reducing suicide deaths, attempts, and ideation in various clinical populations. Available treatments include clozapine, lithium, antidepressants, antipsychotics, electroconvulsive therapy, and transcranial magnetic stimulation. The novel repurposing of ketamine as a potential suicide risk-mitigating agent in the acute setting is also discussed. Research pathways to better understand and treat suicidal ideation and behavior from a neurobiological perspective are proposed in light of this foundation of information and the limitations and challenges inherent in suicide research. Such pathways include trials of fast-acting medications, registry approaches to identify appropriate patients for trials, identification of biomarkers, neuropsychological vulnerabilities, and endophenotypes through the study of known suicide risk-mitigating agents in hope of determining mechanisms of pathophysiology and the action of protective biological interventions. Reprinted from Am J Prev Med 2014; 47:S195-S203, with permission from Elsevier. Copyright © 2014.

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

Objective

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

Methods

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

Results

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

Conclusions

Training general practitioners warrants wider implementation and testing in other nonpsychiatrist physi- cian settings. Active follow-up of patients after discharge or a suicide-related crisis should be routine, and restricting firearm access by at-risk individuals warrants wider use. Combination approaches in health care systems show promise in reducing suicide in several countries, but evaluating the benefit attributable to each component is essential. Further suicide rate reduction requires evaluating newer approaches, such as electronic health record-derived algorithms, Internet-based screening methods, ketamine's potential benefit for preventing attempts, and passive monitoring of acute suicide risk change.Reprinted from Am J Psychiatry 2021; 178:611-624, with permission from American Psychiatric Association Publishing. Copyright © 2021.

Machine learning prediction of suicidal ideation, planning, and attempt among Korean adults: A population-based study

Background

Suicide remains the leading cause of premature death in South Korea. This study aims to develop machine learning algorithms for screening Korean adults at risk for suicidal ideation and suicide planning or attempt.

Methods

Two sets of balanced data for Korean adults aged 19–64 years were drawn from the 2012–2019 waves of the Korea Welfare Panel Study using the random down-sampling method (N = 3292 for the prediction of suicidal ideation, N = 488 for the prediction of suicide planning or attempt). Demographic, socioeconomic, and psychosocial characteristics were used to predict suicidal ideation and suicide planning or attempt. Four machine-learning classifiers (logistic regression, random forest, support vector machine, and extreme gradient boosting) were tuned and cross-validated.

Results

All four algorithms demonstrated satisfactory classification performance in predicting suicidal ideation (sensitivity 0.808–0.853, accuracy 0.843–0.863) and suicide planning or attempt (sensitivity 0.814–0.861, accuracy 0.864–0.884). Extreme gradient boosting was the best-performing algorithm for predicting both suicidal outcomes. The most important predictors were depressive symptoms, self-esteem, income, consumption, and life satisfaction. The algorithms trained with the top two predictors, depressive symptoms and self-esteem, showed comparable classification performance in predicting suicidal ideation (sensitivity 0.801–0.839, accuracy 0.841–0.846) and suicide planning or attempt (sensitivity 0.814–0.837, accuracy 0.874–0.884).

Limitations

Suicidal ideation and behaviors may be under-reported due to social desirability bias. Causality is not established.

Discussion

More than 80% of individuals at risk for suicidal ideation and suicide planning or attempt could be predicted by a number of mental and socioeconomic characteristics of respondents. This finding suggests the potential of developing a quick screening tool based on the known risk factors and applying it to primary care or community settings for early intervention.

•

This study develops machine learning models to predict suicidal ideation and behaviors.

•

Logistic regression, random forest, support vector machine, and extreme gradient boosting are used.

•

The algorithms correctly identifyed 80–90% of suicidal cases.

•

The algorithms with the top two predictors (depressive symptoms and self-esteem) could achieve comparable accuracy.

•

Our findings can be used to design a quick screening tool for use in primary care or community settings.

Does Long-Term Post-Bariatric Weight Change Differ Across Antidepressants?

We sought to evaluate whether weight change up to 5 years after bariatric surgery differed by antidepressant class taken before surgery.

Background

Bariatric surgery induces significant weight loss, but outcomes are highly variable. The specific type of antidepressant used prior to surgery may be an important factor in long-term weight loss.

Methods

This retrospective cohort study from 2000 to 2016 compared the 5-year weight loss of 556 Veterans who were taking antidepressant monotherapy (bupropion, selective serotonin reuptake inhibitors [SSRIs], or serotonin-norepinephrine reuptake inhibitors [SNRIs]) before bariatric surgery (229 sleeve gastrectomy and 327 Roux-en-Y gastric bypass) versus 556 matched nonsurgical controls.

Results

Patients taking bupropion before sleeve gastrectomy had greater differential weight loss between surgical patients and matched controls than those taking SSRIs at 1 (8.9 pounds; 95% confidence interval [CI], 1.6-16.3; P = 0.02) and 2 years (17.6 pounds; 95% CI, 5.9-29.3; P = 0.003), but there was no difference at 5 years (11.9 pounds; 95% CI, -8.9 to 32.8; P = 0.26). Findings were similar for gastric bypass patients taking bupropion compared to SSRIs at 1 (9.7 pounds; 95% CI, 2.0-17.4; P = 0.014), 2 (12.0 pounds; 95% CI, -0.5 to 24.5; P = 0.06), and 5 years (4.8 pounds; 95% CI, -16.7 to 26.3; P = 0.66). No significant differences were observed comparing patients taking SNRI versus SSRI medications.

Conclusions

Sleeve gastrectomy and gastric bypass patients taking bupropion had greater weight loss than those taking SSRIs, although these differences may wane over time. Bupropion may be the first-line antidepressant of choice among patients with severe obesity considering bariatric surgery.

Immediate and short-term efficacy of suicide-targeted interventions in suicidal individuals: A systematic review

OBJECTIVES

To address the extreme suicide risk period following a suicidal crisis, we aimed to assess the current evidence for specific healthcare system-based interventions on suicide-related outcomes within one-week or one-month in individuals with current suicidal ideation (SI) or a recent suicide attempt (SA).

METHODS

We performed a database (Medline, Academic Search Complete, PsycARTICLES, the Cochrane library, PubMed) and manual reference search for randomised controlled trials, published between March 2000 and March 2020. Antisuicidal efficacy was defined as SI, SA, or a closely related concept. Quality was assessed with the Cochrane Risk of Bias 2 tool for randomised trials.

RESULTS

Out of 34 trials, five reported ketamine or esketamine superiority over placebo in reducing SI in depressed subjects within one week, while five studies had negative findings. Single trials reported positive results for one-month antisuicidal efficacy of buprenorphine, paroxetine, a crisis response plan, and assertive case management. Most trials were underpowered and had moderate-to-high risk of bias.

CONCLUSIONS

Preliminary mixed evidence suggests the possible utility of several pharmacological (ketamine, esketamine paroxetine, and buprenorphine) and non-pharmacological (a crisis response plan, and assertive case management) interventions. Only the immediate efficacy of ketamine was supported by multiple studies, and replication is needed.

Effects of somatic treatments on suicidal ideation and completed suicides

OBJECTIVE

This work was undertaken to define and characterize the role of currently available somatic treatments in psychiatry in either increasing or reducing the risk for suicide.

METHODS

Members of the Suicide Prevention Task Group of the National Network of Depression Centers performed a literature review of somatic treatments known to increase or reduce the risk for suicide. The reviews ventured to include all relevant information about the risk for both suicide ideation and completed suicides.

RESULTS

Lithium and clozapine are the only two somatic treatments that have high-quality data documenting their antisuicide effects in mood disorders and schizophrenia, respectively. Lithium discontinuation is also associated with increased suicide risk. Ketamine and esketamine may have a small, but immediate, antisuicide effect. Despite the recent Food and Drug Administration approval of esketamine use in depressed suicidal patients, the small disproportional overrepresentation of suicide in subjects who had received esketamine versus placebo (3 vs. 0 among > 3500 subjects) requires ongoing evaluation. The purported antisuicide effect of electroconvulsive therapy is based on low-quality data. The effect of antidepressants is not at all clear. There appears to be direct evidence for antidepressants increasing suicidal ideation and the risk for suicide over the short-term in young people, but indirect (low quality) evidence that antidepressants reduce suicide risk over the long term.

CONCLUSIONS

Clinicians have an expanding pharmacopeia to address suicide potential in their patients. Some of the agents with documented antisuicide effects may also increase suicidality under specific circumstances.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Pharmacological interventions for self-harm in adults

BACKGROUND

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

OBJECTIVES

To assess the effects of pharmacological agents or natural products for SH compared to comparison types of treatment (e.g. placebo or alternative pharmacological treatment) for adults (aged 18 years or older) who engage in SH.

SEARCH METHODS

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

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing pharmacological agents or natural products with placebo/alternative pharmacological treatment in individuals with a recent (within six months of trial entry) episode of SH resulting in presentation to hospital or clinical services. The primary outcome was the occurrence of a repeated episode of SH over a maximum follow-up period of two years. Secondary outcomes included treatment acceptability, treatment adherence, depression, hopelessness, general functioning, social functioning, suicidal ideation, and suicide.

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

We included data from seven trials with a total of 574 participants. Participants in these trials were predominately female (63.5%) with a mean age of 35.3 years (standard deviation (SD) 3.1 years). It is uncertain if newer generation antidepressants reduce repetition of SH compared to placebo (OR 0.59, 95% CI 0.29 to 1.19; N = 129; k = 2; very low-certainty evidence). There may be a lower rate of SH repetition for antipsychotics (21%) as compared to placebo (75%) (OR 0.09, 95% CI 0.02 to 0.50; N = 30; k = 1; low-certainty evidence). However, there was no evidence of a difference between antipsychotics compared to another comparator drug/dose for repetition of SH (OR 1.51, 95% CI 0.50 to 4.58; N = 53; k = 1; low-certainty evidence). There was also no evidence of a difference for mood stabilisers compared to placebo for repetition of SH (OR 0.99, 95% CI 0.33 to 2.95; N = 167; k = 1; very low-certainty evidence), or for natural products compared to placebo for repetition of SH (OR 1.33, 95% CI 0.38 to 4.62; N = 49; k = 1; lo- certainty) evidence.

AUTHORS' CONCLUSIONS

Given the low or very low quality of the available evidence, and the small number of trials identified, there is only uncertain evidence regarding pharmacological interventions in patients who engage in SH. More and larger trials of pharmacotherapy are required, preferably using newer agents. These might include evaluation of newer atypical antipsychotics. Further work should also include evaluation of adverse effects of pharmacological agents. Other research could include evaluation of combined pharmacotherapy and psychological treatment.

Association between cognition and suicidal ideation in patients with major depressive disorder: A longitudinal study

BACKGROUND

Suicidal ideation (SI) is common in patients with major depressive disorder (MDD) and often related to cognitive deficits. Limited longitudinal study has shown that cognitive improvement is associated with reduced SI. However, the comparatively study in Chinese depressed patients is still absent. The objective of this study was to explore the specific cognitive deficits in Chinese MDD with SI and investigate the relationship between changes in cognition and change in SI across antidepressant treatment.

METHODS

Three hundred and five patients with MDD received four weeks of antidepressant treatment. The 17-item Hamilton Depression Rating Scale (HAMD-17) and four domains of the MATRICS Consensus Cognitive Battery (MCCB), including speed of processing, working memory, visual learning and verbal learning were measured at baseline and four-week follow-up.

RESULTS

One hundred and thirty patients (42.6%) expressed suicidal ideation. Suicidal patients performed worse on verbal learning than non-suicidal patients. Change in speed of processing domain was negatively associated with change in suicidal scores over time. Logistic regression analysis showed that reduction of SI was associated with improvement of speed of processing.

LIMITATION

The major limitation was that there was no healthy control group in the current study, which might limit the interpretation of cognitive deficits in depressed patients with SI.

CONCLUSIONS

Our findings suggest that suicidal patients performed worse on verbal learning which can potentially serve as a cognitive biomarker of suicide risk in MDD. Moreover, reduced suicidal ideation was associated with improved speed of processing.

Suicidal ideation and behavior in adults with major depressive disorder treated with vortioxetine: post hoc pooled analyses of randomized, placebo-controlled, short-term and open-label, long-term extension trials

OBJECTIVES

This study aimed to evaluate the risk of suicidal ideation and behavior associated with vortioxetine treatment in adults with major depressive disorder (MDD).

METHODS

Suicide-related events were evaluated post hoc using 2 study pools: one short-term pool of 10 randomized, placebo-controlled studies (6-8 weeks) and another long-term pool that included 3 open-label extension studies (52 weeks). Evaluation of suicide-related events was performed using Columbia-Suicide Severity Rating Scale (C-SSRS) scores and treatment-emergent adverse events (TEAEs) data.

RESULTS

At baseline, the percentage of patients reporting any C-SSRS ideation or behavior events in short-term studies was similar between placebo (14.7%), vortioxetine (19.8%, 13.0%, 11.2%, and 13.7% for 5-, 10-, 15-, and 20-mg groups, respectively), and duloxetine active reference (13.2%) and did not change throughout the 6- to 8-week treatment period for placebo (17.0%), vortioxetine (19.3%, 13.5%, 12.6%, and 15% for 5-, 10-, 15-, and 20-mg groups, respectively), or duloxetine (11.3%). The incidence of suicide-related events for TEAEs in the short-term pool was 0.4% for placebo, 0.2% or 1.0% for vortioxetine 5 mg or 10 mg, and 0.7% each for vortioxetine 15 mg and 20 mg, as well as duloxetine. After 52-week treatment with vortioxetine, suicidal ideation based on C-SSRS was 9.8%, C-SSRS suicidal behavior was 0.2%, and the incidence of suicide-related events based on TEAEs was <1%. There were no completed suicides in any study.

CONCLUSIONS

Vortioxetine is not associated with increased risk of suicidal ideation or behavior in MDD patients.

The Need for Innovation in Health Care Systems to Improve Suicide Prevention

Suicide rates have continued to rise in the United States. Speculations for this rise proliferate but the causes for the increase remain unknown. While research focuses on identifying causes, the health care system is an important site for identification of patients at risk. Forty percent of individuals who die by suicide were seen in primary care in the month prior to suicide. The Zero Suicide model describes a comprehensive approach for health care systems to aid in identification and intervention of suicidal patients. While this model promises to improve care of suicidal patients, the need for innovation in our approach to understanding and caring for suicidal patients is pressing. Use of technology to enhance moment-to-moment monitoring of at-risk individuals offers promise and the possibility of intervening close to escalation of acute suicidal states. Further, once identified, suicidal individuals are often difficult to engage in treatment. Novel approaches to engagement and treatment that are effective and acceptable to suicidal patients ought to be developed. Specifically, males are much more likely than females to die by suicide. At the same time, males are less likely to seek and remain in the treatments we have to offer. Innovation should seek to identify strategies that are acceptable to males. Additionally, while about half of psychiatric inpatient admissions are suicide related, there is a paucity of suicide-specific psychosocial interventions available for inpatient settings. Innovation in monitoring and treatment offer promise in helping to reduce suicidal behavior in the United States.

Suicide and suicide risk

Although recent years have seen large decreases in the overall global rate of suicide fatalities, this trend is not reflected everywhere. Suicide and suicidal behaviour continue to present key challenges for public policy and health services, with increasing suicide deaths in some countries such as the USA. The development of suicide risk is complex, involving contributions from biological (including genetics), psychological (such as certain personality traits), clinical (such as comorbid psychiatric illness), social and environmental factors. The involvement of multiple risk factors in conveying risk of suicide means that determining an individual's risk of suicide is challenging. Improving risk assessment, for example, by using computer testing and genetic screening, is an area of ongoing research. Prevention is key to reduce the number of suicide deaths and prevention efforts include universal, selective and indicated interventions, although these interventions are often delivered in combination. These interventions, combined with psychological (such as cognitive behavioural therapy, caring contacts and safety planning) and pharmacological treatments (for example, clozapine and ketamine) along with coordinated social and public health initiatives, should continue to improve the management of individuals who are suicidal and decrease suicide-associated morbidity.

Potentiation of Antidepressant Effects of Agomelatine and Bupropion by Hesperidin in Mice

Hesperidin, a well-known flavanone glycoside mostly found in citrus fruits, showed neuroprotective and antidepressant activity. Agomelatine, a melatonergic MT1/MT2 agonist and 5-HT2C receptor antagonist, exhibits good antidepressant efficacy. Bupropion has been widely used for the treatment of depression because of its dopamine and norepinephrine reuptake inhibition. The objective of present study was to assess the antidepressant effects of hesperidin combination with agomelatine or bupropion. Male Swiss Albino mice received treatment of saline, vehicle, 'hesperidin alone', 'agomelatine alone', hesperidin+agomelatine, 'bupropion alone', hesperidin+bupropion, and agomelatine+bupropion for 14 days. The immobility period was analysed 30 min after the treatment in forced swim and tail suspension tests. Dopamine and serotonin levels were analysed in hippocampus, cerebral cortex, and whole brain using HPLC with fluorescence detector. Hesperidin plus agomelatine treated group was better in terms of decrease in immobility period and increase in dopamine and serotonin levels when compared to their respective monotherapy treated groups.

Association of aggression and suicide behaviors: A school-based sample of rural Chinese adolescents

BACKGROUND

To determine the prevalence of suicide behaviors and the associations between aggression and suicide behaviors among a nationwide school-based sample of adolescents in rural China.

METHODS

A total of 16,271 students from 24 junior and 23 senior high schools in five provinces of China participated in a self-administered anonymous survey to report suicide ideation, plans, attempts, aggression and other related information. Multivariable logistic regression models were used to investigate the associations between aggression and the risks of suicide behaviors while controlling for potential confounders.

RESULTS

The prevalence of suicide ideation, plans, and attempts during the past one year was 15.1%, 7.2%, and 3.5% respectively. In the fully adjusted model, participants with high level of total aggression had 4.31 times (95% CI, 3.69-5.05), 4.10 times (95% CI, 3.26-5.11), and 3.29 times (95% CI, 2.62-4.93), higher risk of suicide ideation, plans, and attempts, respectively, compared with subjects who had low level of total aggression. Moreover, high levels of all the five dimensions of total aggression also had positive associations with suicide behaviors.

LIMITATIONS

This study was cross-sectional. Hence, the causal link between aggression and suicide behaviors should be verified in the future studies.

CONCLUSIONS

This study suggests that aggression may be a risk factor for suicide behaviors among rural Chinese adolescents. Our findings highlight the importance of aggression treatment in suicide prevention programs. Further longitudinal studies are needed to confirm these associations.

Effects of anxiety on suicidal ideation: exploratory analysis of a paroxetine versus bupropion randomized trial

It is unclear whether anxiety increases or decreases suicidal risk. This may contribute to the lack of guidance on which antidepressant medications are best for suicidal depressed patients who present with high anxiety. This study explored whether anxiety predicts suicidal ideation in depressed individuals treated with paroxetine or bupropion. An 8-week double-blind trial comparing controlled-release paroxetine (N=36) versus extended-release bupropion (N=38) for effect on suicidal ideation and behavior in depressed patients with suicidal ideation, past attempt, or both found an advantage for paroxetine, but anxiety effects were not investigated. This secondary analysis explored the relationship, measured at baseline and weekly, of anxiety with suicidal ideation. Anxiety severity measured weekly correlated with suicidal ideation severity irrespective of treatment (P=0.012). Patients with high baseline anxiety showed a trend toward faster reduction of suicidal ideation with paroxetine compared with bupropion treatment (standard P=0.047; bootstrap P=0.077). The latter finding, if confirmed in larger samples, could enhance choice of antidepressant medication for suicidal, depressed patients presenting with high levels of anxiety.

Ketamine for Rapid Reduction of Suicidal Thoughts in Major Depression: A Midazolam-Controlled Randomized Clinical Trial

OBJECTIVE

Pharmacotherapy to rapidly relieve suicidal ideation in depression may reduce suicide risk. Rapid reduction in suicidal thoughts after ketamine treatment has mostly been studied in patients with low levels of suicidal ideation. The authors tested the acute effect of adjunctive subanesthetic intravenous ketamine on clinically significant suicidal ideation in patients with major depressive disorder.

METHOD

In a randomized clinical trial, adults (N=80) with current major depressive disorder and a score ≥4 on the Scale for Suicidal Ideation (SSI), of whom 54% (N=43) were taking antidepressant medication, were randomly assigned to receive ketamine or midazolam infusion. The primary outcome measure was SSI score 24 hours after infusion (at day 1).

RESULTS

The reduction in SSI score at day 1 was 4.96 points greater for the ketamine group compared with the midazolam group (95% CI=2.33, 7.59; Cohen's d=0.75). The proportion of responders (defined as having a reduction ≥50% in SSI score) at day 1 was 55% for the ketamine group and 30% for the midazolam group (odds ratio=2.85, 95% CI=1.14, 7.15; number needed to treat=4.0). Improvement in the Profile of Mood States depression subscale was greater at day 1 for the ketamine group compared with the midazolam group (estimate=7.65, 95% CI=1.36, 13.94), and this effect mediated 33.6% of ketamine's effect on SSI score. Side effects were short-lived, and clinical improvement was maintained for up to 6 weeks with additional optimized standard pharmacotherapy in an uncontrolled follow-up.

CONCLUSIONS

Adjunctive ketamine demonstrated a greater reduction in clinically significant suicidal ideation in depressed patients within 24 hours compared with midazolam, partially independently of antidepressant effect.

Suicidal ideation declines with improvement in the subjective symptoms of major depression

BACKGROUND

Suicidal ideation appears to be more strongly associated with subjective rather than neurovegetative symptoms of depression. Effective treatment, then, should produce reductions in suicidal ideation to the degree that these subjective symptoms are alleviated relative to treatment effects on other symptoms.

METHODS

In a randomized clinical trial comparing paroxetine and bupropion for treatment of depression in patients with either suicidal ideation or past attempt, depression severity and suicidal ideation were assessed weekly during the 8-week study. Depression rating scales - the 24-item Hamilton Depression Rating Scale [HDRS] and the Beck Depression Scale [BDI] - were decomposed into symptom clusters based on our published factor analyses, and their change over time compared to changes on the Beck Scale for Suicidal Ideation [SSI].

RESULTS

Improvement in factor scores associated with subjective symptoms of depression - HDRS Psychic Depression, BDI Subjective Depression, and BDI Self-Blame - were the best predictors of declining scores on the SSI regardless of type of drug treatment. BDI Subjective Depression was the best single predictor in the context of all other significant univariate predictors, accounting for 31.4% of the variance in the change in SSI. The three factors together accounted for 35.3%.

LIMITATIONS

This is a secondary analysis of clinical trial data, with fixed treatments.

CONCLUSIONS

Effective treatments to reduce suicidal ideation are associated with the reduction of the subjective symptoms of depression, which may not always decline in synchrony with improvement in neurovegetative symptoms. This asynchrony may result in a period of elevated risk after the initiation of therapy. Data indicate that subjective depression symptoms should be a primary target in the treatment of depressed suicidal patients.

Ketamine versus midazolam in bipolar depression with suicidal thoughts: A pilot midazolam-controlled randomized clinical trial

OBJECTIVES

To evaluate feasibility and effects of a sub-anesthetic infusion dose of ketamine versus midazolam on suicidal ideation in bipolar depression. Neurocognitive, blood and saliva biomarkers were explored.

METHODS

Sixteen participants with bipolar depression and a Scale for Suicidal Ideation (SSI) score of ≥4 were randomized to ketamine (0.5 mg/kg) or midazolam (0.02 mg/kg). Current pharmacotherapy was maintained excluding benzodiazepines within 24 hours. The primary clinical outcome was SSI score on day 1 post-infusion.

RESULTS

Results supported feasibility. Mean reduction of SSI after ketamine infusion was almost 6 points greater than after midazolam, although this was not statistically significant (estimate=5.84, SE=3.01, t=1.94, P=.074, 95% confidence interval ([CI)]=-0.65 to 12.31). The number needed to treat for response (SSI <4 and at least 50% below baseline) was 2.2, and for remission (SSI=0) was 3.2. The strongest neurocognitive correlation was between memory improvement on the Selective Reminding Test (SRT) and reduction in SSI score on day 1 after ketamine (ρ=-.89, P=.007). Pre- to post-infusion decrease in serum brain derived neurotrophic factor (BDNF) correlated with reduction in SSI from baseline to day 1 after ketamine (n=5, ρ=0.90, P=.037) but not midazolam (P=.087).

CONCLUSIONS

The study demonstrated feasibility. Suicidal thoughts were lower after ketamine than after midazolam at a trend level of significance, likely due to the small pilot sample. Memory improvement and BDNF are promising biomarkers. Replication is needed in an adequately powered full-scale trial.

SUICIDAL DEPRESSED PATIENTS RESPOND LESS WELL TO ANTIDEPRESSANTS IN THE SHORT TERM

BACKGROUND

Suicidal thoughts and behaviors could be associated to a poor response to antidepressant treatment, but the exclusion of suicidal patients from randomized clinical trials restricts the available knowledge. In this study, we aimed at defining more precisely the response to antidepressants among suicidal patients and the threshold of suicidality that best predicts a poor response.

METHOD

We investigated the short-term response to a new antidepressant treatment of 4,041 depressed outpatients depending on their suicidal status (passive or active suicidal ideation (SI), history of suicide attempts [SAs]), either self-rated or clinician-rated. Depression outcomes, measured with the Hospital Anxiety and Depression Scale, and remission rates were compared depending on suicidal status at baseline using logistic regression models.

RESULTS

Using either a qualitative or a quantitative approach to measure SI, we found that suicidal patients were less likely to improve or attain remission, but not more likely to worsen, than nonsuicidal patients. In the multivariate analyses, SI (odds ratio [OR] = 1.40; 95% confidence interval [CI]: 1.18-1.65) and a history of SA (OR = 1.39; 95% CI: 1.16-1.66) were the best predictors of nonremission, independently of the class of antidepressant treatment.

CONCLUSION

Antidepressant treatment seems to be less effective among those patients that need it most. Clinical trials including suicidal patients are needed to investigate specific treatment options.

Bupropion: a systematic review and meta-analysis of effectiveness as an antidepressant

Bupropion has been used as an antidepressant for over 20 years, though its licence for such use varies and it is typically a third- or fourth-line agent. It has a unique pharmacology, inhibiting the reuptake of noradrenaline and dopamine, potentially providing pharmacological augmentation to more common antidepressants such as selective serotonergic reuptake inhibitors (SSRIs). This systematic review and meta-analysis identified 51 studies, dividing into four categories: bupropion as a sole antidepressant, bupropion coprescribed with another antidepressant, bupropion in 'other' populations (e.g. bipolar depression, elderly populations) and primary evaluation of side effects. Methodologically more robust trials support the superiority of bupropion over placebo, and most head-to-head antidepressant trials showed an equivalent effectiveness, though some of these are hindered by a lack of a placebo arm. Most work on the coprescribing of bupropion with another antidepressant supports an additional effect, though many are open-label trials. Several large multi-medication trials, most notably STAR*D, also support a therapeutic role for bupropion; in general, it demonstrated similar effectiveness to other medications, though this literature highlights the generally low response rates in refractory cohorts. Effectiveness has been shown in 'other' populations, though there is an overall dearth of research. Bupropion is generally well tolerated, it has very low rates of sexual dysfunction, and is more likely to cause weight loss than gain. Our findings support the use of bupropion as a sole or coprescribed antidepressant, particularly if weight gain or sexual dysfunction are, or are likely to be, significant problems. However there are notable gaps in the literature, including less information on treatment naïve and first presentation depression, particularly when one considers the ever-reducing rates of response in more refractory illness. There are some data to support bupropion targeting specific symptoms, but insufficient information to reliably inform such prescribing, and it remains uncertain whether bupropion pharmacodynamically truly augments other drugs.

Suicide and suicidal behaviour

Suicide is a complex public health problem of global importance. Suicidal behaviour differs between sexes, age groups, geographic regions, and sociopolitical settings, and variably associates with different risk factors, suggesting aetiological heterogeneity. Although there is no effective algorithm to predict suicide in clinical practice, improved recognition and understanding of clinical, psychological, sociological, and biological factors might help the detection of high-risk individuals and assist in treatment selection. Psychotherapeutic, pharmacological, or neuromodulatory treatments of mental disorders can often prevent suicidal behaviour; additionally, regular follow-up of people who attempt suicide by mental health services is key to prevent future suicidal behaviour.

Identifying a clinical signature of suicidality among patients with mood disorders: A pilot study using a machine learning approach

OBJECTIVE

A growing body of evidence has put forward clinical risk factors associated with patients with mood disorders that attempt suicide. However, what is not known is how to integrate clinical variables into a clinically useful tool in order to estimate the probability of an individual patient attempting suicide.

METHOD

A total of 144 patients with mood disorders were included. Clinical variables associated with suicide attempts among patients with mood disorders and demographic variables were used to 'train' a machine learning algorithm. The resulting algorithm was utilized in identifying novel or 'unseen' individual subjects as either suicide attempters or non-attempters. Three machine learning algorithms were implemented and evaluated.

RESULTS

All algorithms distinguished individual suicide attempters from non-attempters with prediction accuracy ranging between 65% and 72% (p<0.05). In particular, the relevance vector machine (RVM) algorithm correctly predicted 103 out of 144 subjects translating into 72% accuracy (72.1% sensitivity and 71.3% specificity) and an area under the curve of 0.77 (p<0.0001). The most relevant predictor variables in distinguishing attempters from non-attempters included previous hospitalizations for depression, a history of psychosis, cocaine dependence and post-traumatic stress disorder (PTSD) comorbidity.

CONCLUSION

Risk for suicide attempt among patients with mood disorders can be estimated at an individual subject level by incorporating both demographic and clinical variables. Future studies should examine the performance of this model in other populations and its subsequent utility in facilitating selection of interventions to prevent suicide.

A multi-site randomized clinical trial to reduce suicidal ideation in suicidal adult outpatients with Major Depressive Disorder: Development of a methodology to enhance safety

BACKGROUND/AIMS

Suicide is a major public health concern, yet there are very few randomized clinical trials that have been conducted to reduce suicidal ideation in patients at risk of suicide. We describe the rationale and refinements of such a trial that is designed to assess the effect of a hypnotic medication on suicidal ideation in adult outpatients currently experiencing suicidal ideation.

METHODS

"Reducing Suicidal Ideation Through Insomnia Treatment" is a multi-site randomized clinical trial that includes three recruiting sites and one data management site. This 4-year study is in its second year of recruitment. The purpose of the study is to compare hypnotic medication versus placebo as an add-on treatment to a selective serotonin reuptake inhibitor as a means of reducing suicidal ideation in depressed adult outpatients with insomnia and suicidal ideation. The safety features of the study follow the 2001 National Institutes of Health guidelines for studies that include patients at risk of suicide.

RESULTS

In total, 584 potential participants have undergone telephone screening; 67% of these failed the phone screen, most often due to an absence of expressed suicidal ideation (26% of the telephone screen fails). A total of 115 people appeared for a face-to-face baseline assessment, and 40 of these had completed a taper off of their ineffective psychotropic medications before the baseline assessments. In all, 64% of those who completed baseline assessments failed to proceed to randomization, most commonly because of no clinically significant suicidal ideation (51% of those excluded at baseline). One participant was offered and accepted voluntary psychiatric hospitalization in lieu of study participation. Thus far, 40 participants have been randomized into the study and 88.7% of scheduled visits have been attended, with 93.8% adherence to the selective serotonin reuptake inhibitor and 91.6% adherence to the randomized hypnotic versus placebo. None of the randomized participants have required hospitalization or had a suicide attempt.

CONCLUSION

By carefully considering the inclusion and exclusion criteria and other safety features, the safe conduct of randomized clinical trials in suicidal adult patients is possible, including the inclusion of participants who have undergone a prescribed tapering off of psychotropic medications prior to baseline assessment.

Treatment-related improvement in neuropsychological functioning in suicidal depressed patients: paroxetine vs. bupropion

Neuropsychological dysfunction is associated with risk for suicidal behavior, but it is unknown if antidepressant medication treatment is effective in reducing this dysfunction, or if specific medications might be more beneficial. A comprehensive neuropsychological battery was administered at baseline and after 8 weeks of treatment within a randomized, double-blind clinical trial comparing paroxetine and bupropion in patients with DSM-IV Major Depressive Disorder and either past suicide attempt or current suicidal thoughts. Change in neurocognitive performance was compared between assessments and between medication groups. Treatment effects on the Hamilton Depression Rating Scale and Scale for Suicide Ideation were compared with neurocognitive improvement. Neurocognitive functioning improved after treatment in all patients, without clear advantage for either medication. Improvement in memory performance was associated with a reduction in suicidal ideation independent of the improvement of depression severity. Overall, antidepressant medication improved neurocognitive performance in patients with major depression and suicide risk. Reduced suicidal ideation was best predicted by a combination of the independent improvements in both depression symptomatology and verbal memory. Targeted treatment of neurocognitive dysfunction in these patients may augment standard medication treatment for reducing suicidal behavior risk.

Use of antidepressant medication and suicidal ideation-the Northern Finland Birth Cohort 1966

OBJECTIVE

The aim was to study the association between use of antidepressant medication and suicidal ideation in different diagnostic groups in a large population-based cohort.

METHODS

Information on prescribed drugs within the Northern Finland Birth Cohort 1966 was collected at the age of 31 years with postal questionnaire (N= 8218). The presence of suicidal ideation was assessed via the Hopkins Symptom Checklist-25 questionnaire. We studied associations between suicidal ideation and antidepressant medication in various diagnostic and symptom groups, and it adjusted for symptoms of depression and anxiety.

RESULTS

Suicidal ideation was associated with the use of antidepressant medication in all diagnostic groups, but the association disappeared with adjustment for other symptoms of depression and anxiety. Subjects who reported insomnia and used antidepressants had suicidal ideation more commonly than did subjects who were not using antidepressants even when other symptoms were adjusted for (p = 0.02). There were no statistically significant differences between antidepressant groups or doses.

CONCLUSION

In a large unselected cohort, antidepressant medication was not associated with increased suicidal ideation when other symptoms of depression and anxiety were taken into account. The assessment of insomnia might be useful for identifying individuals liable to have increased suicidal ideation while on antidepressant medication.

Existing and novel biological therapeutics in suicide prevention

We summarize outcomes for several pharmacologic and neurostimulatory approaches that have been considered potential treatments to reduce suicide risk, namely, by reducing suicide deaths, attempts, and ideation in various clinical populations. Available treatments include clozapine, lithium, antidepressants, antipsychotics, electroconvulsive therapy, and transcranial magnetic stimulation. The novel repurposing of ketamine as a potential suicide risk-mitigating agent in the acute setting is also discussed. Research pathways to better understand and treat suicidal ideation and behavior from a neurobiological perspective are proposed in light of this foundation of information and the limitations and challenges inherent in suicide research. Such pathways include trials of fast-acting medications, registry approaches to identify appropriate patients for trials, identification of biomarkers, neuropsychological vulnerabilities, and endophenotypes through the study of known suicide risk-mitigating agents in hope of determining mechanisms of pathophysiology and the action of protective biological interventions.

The neurobiology of suicide

The stress-diathesis model posits that suicide is the result of an interaction between state-dependent (environmental) stressors and a trait-like diathesis or susceptibility to suicidal behaviour, independent of psychiatric disorders. Findings from post-mortem studies of the brain and from genomic and in-vivo neuroimaging studies indicate a biological basis for this diathesis, indicating the importance of neurobiological screening and interventions, in addition to cognitive and mood interventions, in the prevention of suicide. Early-life adversity and epigenetic mechanisms might explain some of the link between suicide risk and brain circuitry and neurochemistry abnormalities. Results from a range of studies using diverse designs and post-mortem and in-vivo techniques show impairments of the serotonin neurotransmitter system and the hypothalamic-pituitary-adrenal axis stress-response system in the diathesis for suicidal behaviour. These impairments manifest as impaired cognitive control of mood, pessimism, reactive aggressive traits, impaired problem solving, over-reactivity to negative social signs, excessive emotional pain, and suicidal ideation, leading to suicidal behaviour. Biomarkers related to the diathesis might help to inform risk-assessment procedures and treatment choice in the prevention of suicide.

SSRI versus bupropion effects on symptom clusters in suicidal depression: post hoc analysis of a randomized clinical trial

OBJECTIVE

Identifying the depression symptoms most closely associated with suicidal thoughts and which medications provide the fastest depression relief may help suicide prevention.

METHOD

Post hoc analysis of data from a randomized, double-blind, 8-week clinical trial of the selective serotonin reuptake inhibitor paroxetine controlled release (n = 36) versus the norepinephrine-dopamine reuptake inhibitor bupropion extended release (n = 38) was conducted in patients with DSM-IV major depressive disorder and past suicide attempt or current suicidal thoughts. Treatment effects on Hamilton Depression Rating Scale (HDRS) and Beck Depression Inventory symptom clusters were compared. We hypothesized that paroxetine would demonstrate a superior effect on nonsuicidal, affective/cognitive depression symptom clusters that our prior work found to be associated with suicidal thoughts and attempts. Data were collected from February 2005 to January 2010.

RESULTS

There was a treatment main effect on HDRS psychic depression (depressed mood, guilt, retardation, helpless, hopeless, worthless) (estimate = -2.2; 95% CI, -3.2 to -1.1; t67.16 = -4.01; P < .001), one of the clusters most strongly correlated to suicidal ideation. The net drug effect demonstrated that mean psychic depression score was 2.2 points lower after 1 week of paroxetine compared to bupropion treatment. The significance level of this effect was P < .001 at weeks 1 and 2, P = .012 at week 3 and P = .051 at week 4. Results for other depression scale factors were nonsignificant (P > .05).

CONCLUSIONS

The results require replication but suggest a pathway by which selective serotonin reuptake inhibitor treatment may exert a stronger effect compared with norepinephrine-dopamine reuptake inhibitor treatment on reduction of suicidal thoughts during initial weeks of pharmacotherapy in these higher risk patients.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00429169.

NEUROBIOLOGICAL ASPECTS OF SUICIDE AND SUICIDE ATTEMPTS IN BIPOLAR DISORDER

Suicide and bipolar disorder (BD) are challenging, complex, and intertwined areas of study in contemporary psychiatry. Indeed, BD is associated with the highest lifetime risk for suicide attempt and completion of all the psychiatric conditions. Given that several clinical risk factors for both suicide and BD have been well noted in the literature, exploring the neurobiological aspects of suicide in BD may provide insights into both preventive measures and future novel treatments. This review synthesizes findings regarding the neurobiological aspects of suicide and, when applicable, their link to BD. Neurochemical findings, genes/epigenetics, and potential molecular targets for current or future treatments are discussed. The role of endophenotypes and related proximal and distal risk factors underlying suicidal behavior are also explored. Lastly, we discuss the manner in which preclinical work on aggression and impulsivity may provide additional insights for the future development of novel treatments.