Attention deficit in depressed suicide attempters

The impact of antidepressant treatment on the network structure of neurocognition and core emotional depressive symptoms among depressed individuals with a history of suicide attempt: An 8-week clinical study

BACKGROUND

A more in-depth understanding of the relationship between depressive symptoms, neurocognition and suicidal behavior could provide insights into the prognosis and treatment of major depressive disorder (MDD) and suicide. We conducted a network analysis among depressed patients examining associations between history of suicide attempt (HSA), core emotional major depression disorder, and key neurocognitive domains.

METHOD

Depressed patients (n = 120) aged 18-65 years were recruited from a larger randomized clinical trial conducted at the Douglas Institute in Montreal, Canada. They were randomly assigned to receive one of two antidepressant treatments (i.e., escitalopram or desvenlafaxine) for 8 weeks. Core emotional MDD and key neurocognitive domains were assessed pre-post treatment.

RESULTS

At baseline, an association between history of suicide attempt (HSA) and phonemic verbal fluency (PVF) suggested that HSA patients reported lower levels of the latter. After 8 weeks of antidepressant treatment, HSA became conditionally independent from PVF. Similar results were found for both the HAM-D and the QIDS-SR core emotional MDD/neurocognitive networks.

CONCLUSION

Network analysis revealed a pre-treatment relationship between a HSA and decreased phonemic VF among depressed patients, which was no longer present after 8 weeks of antidepressant treatment.

Association between cognitive functioning, suicidal ideation and suicide attempts in major depressive disorder, bipolar disorder, schizophrenia and related disorders: A systematic review and meta-analysis

INTRODUCTION

Treatable mental disorders, such as psychotic, major depressive disorder (MDD), and bipolar disorder (BD), contribute to a substantial portion of suicide risk, often accompanied by neurocognitive deficits. We report the association between cognitive function and suicidal ideation/suicide attempts (SI/SA) in individuals with schizoaffective disorder, BD, and MDD.

METHODS

A systematic search was conducted on PubMed, Ovid and Scopus databases for primary studies published from inception to April 2024. Eligible articles that reported on the effect size of association between cognition and SI/SA were pooled using a random effects model.

RESULTS

A total of 41 studies were included for analysis. There was a negative association between executive functioning and SI/SA in schizoaffective disorder (SA: Corr = -0·78, 95 % CI [-1·00, 0·98]; SI: Corr = -0·06, 95 % CI [-0·85, 0·82]) and MDD (SA: Corr = -0·227, 95 % CI [-0·419, -0·017]; SI: Corr = -0·14, 95 % CI [-0·33, 0·06]). Results were mixed for BD, with a significant positive association between SA and global executive functioning (Corr = 0·08, 95 % CI [0·01, 0·15]) and negative association with emotion inhibition. Mixed results were observed for processing speed, attention, and learning and memory, transdiagnostically.

LIMITATIONS

There is heterogeneity across sample compositions and cognitive measures. We did not have detailed information on individuals with respect to demographics and comorbidities.

CONCLUSIONS

We observed a transdiagnostic association between measures of cognitive functions and aspects of suicidality. The interplay of cognitive disturbances, particularly in reward-based functioning, may underlie suicidality in individuals with mental disorders. Disturbances in impulse control, planning, and working memory may contribute to self-injurious behavior and suicide.

Attention-Dominated Cognitive Dysfunction May Be a Biological Marker for Distinguishing SA from SI in Adolescents: A Network Analysis Study Based on Adolescent Depression

Objective

Suicidal behavior is strongly correlated with depressive symptoms and the degree of suicidal ideation. Cognitive impairment may have varying degrees of influence on suicidal ideation (SI) and suicidal attempts (SA). The aim of this study was to identify the cognitive biomarkers that distinguish suicidal ideation from suicidal attempts in adolescents.

Methods

The cross-sectional sample comprised 54 adolescents with major depressive disorder (MDD) and 32 healthy controls (HC). The THINC-it was utilized to assess cognitive function of all the samples. Suicidal ideation was examined by the Positive and Negative Suicide Ideation Scale (PANSI). Based on the type of data, one-way ANOVA or Kruskal-Wallis was performed to investigate group differences. Bonferroni post-hoc analysis was employed for regulating type I error for pairwise comparisons. Network analysis was used to compare the networks associated with suicidal ideation, depression symptoms, and cognitive function between SA and SI.

Results

The depression symptoms (HAMD-17) (F=72.515, P<0.001) and suicidal ideation (PANSI) (F=267.952, P<0.001) in the SA were higher than those in the SI. Analysis of between-group differences showed SA performed worse in THINC-it, especially in "Spotter (SP)" (P=0.033), "Objective cognition score (OS)" (P=0.027) and "Composite score (CS)" (P=0.017). Compared with SI, network analysis revealed that SA had a unique network of cognitive function, depressive symptoms, and suicidal ideation. Nevertheless, both networks exhibit comparable performance concerning the node strength of cognitive function. Within their separate networks, the aspects of CS, OS, and SP have emerged as the three most crucial elements.

Conclusion

Adolescents with SI or SA exhibit a broad spectrum of cognitive impairments. Attention impairment can be beneficial in discerning between SI and SA. Future interventions for adolescent suicide can center on attention and the comprehensive cognitive ability that it represents.

Divergent suicidal symptomatic activations converge on somato-cognitive action network in depression

Individuals with depression have the highest lifetime prevalence of suicide attempts (SA) among mental illnesses. Numerous neuroimaging studies have developed biomarkers from task-related neural activation in depressive patients with SA, but the findings are inconsistent. Empowered by the contemporary interconnected view of depression as a neural system disorder, we sought to identify a specific brain circuit utilizing published heterogeneous neural activations. We systematically reviewed all published cognitive and emotional task-related functional MRI studies that investigated differences in the location of neural activations between depressive patients with and without SA. We subsequently mapped an underlying brain circuit functionally connecting to each experimental activation using a large normative connectome database (n = 1000). The identified SA-related functional network was compared to the network derived from the disease control group. Finally, we decoded this convergent functional connectivity network using microscale transcriptomic and chemo-architectures, and macroscale psychological processes. We enrolled 11 experimental tasks from eight studies, including depressive patients with SA (n = 147) and without SA (n = 196). The heterogeneous SA-related neural activations localized to the somato-cognitive action network (SCAN), exhibiting robustness to little perturbations and specificity for depression. Furthermore, the SA-related functional network was colocalized with brain-wide gene expression involved in inflammatory and immunity-related biological processes and aligned with the distribution of the GABA and noradrenaline neurotransmitter systems. The findings demonstrate that the SA-related functional network of depression is predominantly located at the SCAN, which is an essential implication for understanding depressive patients with SA.

The altered temporal properties of dynamic functional connectivity associated with suicide attempt in bipolar disorders

OBJECTIVE

The suicide risk in bipolar disorder (BD) is the highest among psychiatric disorders, and the neurobiological mechanism of suicide in BD remains unclear. The study aimed to investigate the underlying relevance between the implicated abnormalities of dynamic functional connectivity (FC) and suicide attempt (SA) in BD.

METHODS

We used the sliding window method to analyze the dynamic FC patterns from resting-state functional MRI data in 81 healthy controls (HC) and 114 BD patients (50 with SA and 64 with none SA). Then, the temporal properties of dynamic FC and the relationship between altered measures and clinical variables were explored.

RESULTS

We found that one of the five captured brain functional states was more associated with SA. The SA patients showed significantly increased fractional window and dwell time in the suicide-related state, along with increased number of state transitions compared with none SA (NSA). In addition, the connections within subcortical network-subcortical network (SubC-SubC), default mode network-subcortical network (DMN-SubC), and attention network-subcortical network (AN-SubC) were significantly changed in SA patients relative to NSA and HC in the suicide-related state. Crucially, the above-altered measures were significantly correlated with suicide risk.

CONCLUSIONS

Our findings suggested that the impaired dynamic FC within SubC-SubC, DMN-SubC, and AN-SubC were the important underlying mechanism in understanding SA for BD patients. It highlights the temporal properties of whole-brain dynamic FC could serve as the valuable biomarker for suicide risk assessment in BD.

Plasma Phospholipid Polyunsaturated Fatty Acid Associations with Neurocognition

Neurocognitive deficits are implicated in major depressive disorder (MDD) and suicidal behavior, and cognitive function may be affected by blood levels of polyunsaturated fatty acids (PUFAs). Neuroprotective functions have been described for omega-3 (n-3) PUFAs, while omega-6 (n-6) PUFAs exhibit broadly opposing activities. Both classes of PUFAs are linked to MDD and suicidal behavior. However, few studies have investigated the relationships between PUFAs and neurocognitive function with respect to MDD or suicidal behavior. Among participants with MDD (n = 45) and healthy volunteers (HV, n = 30) we assessed performance on tasks of attentional capacity and executive function and its relationship to plasma phospholipid PUFA levels, expressed as a percentage of total plasma phospholipids, for eicosapentaenoic acid (EPA%), docosahexaenoic acid (DHA%), and arachidonic acid (AA%). Regression models tested the correlations between PUFA levels and task performance in three groups: MDD with a history of suicide attempt (SA, n = 20), MDD with no attempts (NA, n = 25), and HV. Interaction testing indicated a significant positive correlation of EPA% with continuous performance test scores in the NA group (F = 4.883, df = 2,72, p = 0.01), a measure of sustained attention. The AA% correlated negatively with performance on two executive function tasks, object alternation (beta = -3.97, z-score = -2.67, p = 0.008) and the Wisconsin card sort (beta = 0.80, t-score = -2.16, df = 69, p = 0.035), after adjustment for group and age, with no group effects. Our findings suggest a role for PUFA imbalance in attentional functioning and executive performance; however, no MDD-specific effect was observed.

Event-Related Potential Markers of Suicidality in Adolescents

BACKGROUND

Implicit cognitive markers may assist with the prediction of suicidality beyond clinical risk factors. The aim of this study was to investigate neural correlates associated with the Death/Suicide Implicit Association Test (DS-IAT) via event-related potentials (ERP) in suicidal adolescents.

METHODS

Thirty inpatient adolescents with suicidal ideations and behaviors (SIBS) and 30 healthy controls from the community were recruited. All participants underwent 64-channel electroencephalography, DS-IAT, and clinical assessments. Hierarchical generalized linear models with spatiotemporal clustering were used to identify significant ERPs associated with the behavioral outcome of DS-IAT (D scores) and group differences.

RESULTS

Behavioral results (D scores) showed that the adolescents with SIBS had stronger implicit associations between "death" and "self" than the healthy group (P = .02). Within adolescents with SIBS, participants with stronger implicit associations between "death" and "self" reported more difficulty in controllability of suicidal ideation in the past 2 weeks based on the Columbia-Suicide Severity Rating Scale (P = .03). For the ERP data, the D scores and N100 component over the left parieto-occipital cortex had significant correlations. Significant group differences without behavioral correlation were observed for a second N100 cluster (P = .01), P200 (P = .02), and late positive potential (5 clusters, all P ≤ .02). Exploratory predictive models combining both neurophysiological and clinical measures distinguished adolescents with SIBS from healthy adolescents.

CONCLUSIONS

Our results suggest that N100 may be a marker of attentional resources involved in the distinction of stimuli that are congruent or incongruent to associations between death and self. Combined clinical and ERP measures may have utility in future refinements of assessment and treatment approaches for adolescents with suicidality.

Safety intervention for improving functioning in suicidal attempters (STRONG): A secondary prevention study. Study rationale and research protocol

BACKGROUND

Suicide is one of the most largely preventable causes of death worldwide. The aim of the STRONG study is to assess the effectiveness of a specific intervention (an extended Safety Planning Intervention) called iFightDepression-SURVIVE (iFD-S) in suicidal attempters by changes in psychosocial functioning. As secondary outcomes, quality of life, cognitive performance, clinical state and neuroimaging correlates will be considered.

OBJECTIVE

To describe the rationale and design of the STRONG study, an extension of the SURVIVE study, a national multicenter cohort about on prevention in suicidal attempters.

METHODS

The STRONG study is a two-year clinical trial. A total sample of 60 patients will be randomly allocated to two arms: a group will receive a iFD-S and treatment as usual (TAU) (n=30 treatment group), while another group will exclusively receive TAU (n=30 control group). There will be three study points: baseline; 3-month; and 6-month follow-up assessments, all of which will include rater-blinded evaluation of psychosocial functioning, quality of life, clinical state, cognitive performance and neuroimaging acquisition.

RESULTS

It is expected to obtain data on the efficacy of iFD-S in patients who have committed a suicide attempt.

CONCLUSION

Results will provide insight into the effectiveness of IFD-S in suicidal attempters with respect to improvements in psychosocial functioning, quality of life, cognition, and neuroimaging correlates.

CLINICAL TRIALS ID

NCT05655390.

Abnormal attentional bias in individuals with suicidal ideation during an emotional Stroop task: an event-related potential study

Introduction

There is increasing evidence that suicidal individuals exhibit an attentional bias toward negative or suicide-related stimuli, but the underlying neural mechanism remains unclear. This study aimed to investigate the neural mechanism of attentional bias toward emotional stimuli using a modified emotional Stroop task (EST) and to further explore the influencing factor of abnormal attention processing by identifying whether mental disorders or suicidal ideation contributes to attention processing disruptions.

Methods

Fourteen students with suicidal ideation and mental disorders (SIMDs), sixteen students with suicidal ideation but no mental disorders (SINMDs), and fourteen sex- and age-matched healthy controls (HCs) were recruited. Moreover, 64-channel electroencephalography (EEG) data and behavioral responses were recorded simultaneously during the EST. Participants were instructed to respond to the ink color for various types of words (positive, neutral, negative, and suicide) while ignoring their meanings. Event-related potentials (ERPs) were analyzed to evaluate attention to the stimuli. Spearman correlations between clinical psychological assessment scales and ERP signatures were analyzed to determine the risk factors for suicide.

Results

The results showed that the SIMD group exhibited longer early posterior negativity (EPN) latency compared to the SINMD and HC groups, indicating that early attention processing was affected during the EST, and the automatic and rapid processing of emotional information decreased. Furthermore, P300 latency for positive words was positively correlated with current suicidal ideation in the SINMD group, suggesting that delayed responses or additional processing to positive information may lead individuals with suicidal ideation to an incorrect interpretation of external events.

Conclusions

Generally, our findings suggest that the neural characteristics of the SIMD group differed from those of the SINMD and HC groups. EPN latency and P300 latency during the EST may be suicide-related neurophysiological indicators. These results provide neurophysiological signatures of suicidal behavior.

Cognitive impairment and factors influencing depression in adolescents with suicidal and self-injury behaviors: a cross-sectional study

BACKGROUND

Non-suicidal self-injury (NSSI) and suicide attempts (SAs) by adolescent patients with depression have become serious public health problems. There is still insufficient research evidence on the effects of NSSI and SAs on neurocognitive functioning in adolescents. Cognitive function alterations may be associated with SAs and self-injury. NSSI and SAs have different influencing factors.

METHODS

Participants were recruited from outpatient clinics and included 142 adolescent patients with depression (12-18 years old). This cohort included the SAs group (n = 52), NSSI group (n = 65), and depression without SAs/NSSI control group (n = 25). All participants underwent a clinical interview and neuropsychological assessment for group comparisons, and post-hoc tests were performed. Finally, partial correlation analysis was used to explore factors related to changes in cognitive function.

RESULTS

The SAs group performed significantly worse than the control group in executive function and working memory. The depression score was directly proportional to the executive function of the SAs group, whereas cognitive functioning in the NSSI group was associated with borderline traits and rumination.

CONCLUSIONS

These findings suggest that impairment of executive function and working memory may be a common pattern in adolescent depressed patients with SAs. However, borderline traits and rumination may be indicative of NSSI but not SAs.

Relationships among insomnia, executive function, and suicidal ideation in depressed outpatients: A mediation analysis

Insomnia is a risk factor for suicide, and both are associated with cognitive problems. However, prior research has not examined insomnia, cognition, and suicidal ideation within one sample. We describe cross-sectional associations among insomnia, psychomotor speed, set shifting, and suicidal ideation in 85 depressed adults. Greater insomnia was associated with slower psychomotor speed, while slower psychomotor speed was associated with a greater level (i.e., elaboration of suicide planning) and intensity of suicidal ideation in the past week. Slower set shifting was associated with a greater level and intensity of suicidal ideation in the past week. Mediation analysis indicated that psychomotor speed and set shifting both had a significant total effect on the intensity of suicidal ideation in the past week; set shifting also had a significant total effect on the sum of intensity and suicidal ideation level in the past week. The level of insomnia explained only small percentages of the total effect of either psychomotor speed or set shifting on the intensity of suicidal ideation and the sum of intensity and suicidal ideation level. The findings in this sample demonstrate significant associations of slower psychomotor speed and set shifting with suicidal ideation, with negligible contribution from insomnia.

Association between childhood cognitive skills & adult suicidal behavior: A systematic review and meta-analysis

BACKGROUND

It is unclear whether cognitive skill deficits during childhood carry risk for suicide attempt or mortality later in adulthood at the population level. We conducted a systematic review and meta-analysis of population-based studies examining the association between childhood cognitive skills and adult suicidal behavior, namely attempt and mortality.

METHOD

We systematically searched databases for articles then extracted study characteristics and estimates on the association between childhood cognitive skills (i.e., IQ or school performance at age ≤ 18 years) and later suicide attempt and mortality. Random-effect meta-analysis was used to quantify this association across all studies with available data.

RESULTS

Twenty-three studies met the inclusion criteria and suggest an association between lower childhood cognitive skills and increased risk of suicidal behavior. Meta-analysis of the adjusted estimates from 11 studies (N = 2,830,191) found the association to be small but statistically significant. Heterogeneity was significant but moderate, and results were unlikely to be influenced by publication bias. In subgroup analyses, associations were significant only for males. No difference in effect size was found between suicide attempt and suicide mortality.

LIMITATIONS

Cognitive skills were measured with different cognitive subtests. Heterogeneity in the age of cognitive skills assessment. Meta-regression and subgroup analyses were based on a relatively low number of studies.

CONCLUSIONS

Individuals with lower cognitive skills in childhood have a greater risk of suicidal behavior in adulthood, especially males. Although the association was small, interventions improving cognitive skills may yield large effects on suicide prevention at the population level if the association is causal.

Cognitive flexibility in inpatient children and adolescents with a history of suicide attempts

An increase in suicide rates during adolescence has made it the second leading cause of death for this age group. While potential deficits in cognitive flexibility have been thought to contribute to suicidality, this factor has been evaluated in only a few studies among this age group. The current study sought to evaluate cognitive flexibility in 100 psychiatric inpatient children and adolescents (age X=14.39, SD=2.53), with (n=26) and without (n=74) a history of suicide attempts, using the Wisconsin Card Sorting Test (WCST). Results showed no differences between the groups in WCST scores. However, in a small sub-sample with mood disorders only, those with a history of a suicide attempt performed better than those without such history. These findings are contrary to our hypothesis that those who attempted suicide have worse cognitive flexibility, though consistent with earlier data in adults. Further research is needed to shed light on these findings.

Attentional control deficits and suicidal ideation variability: An ecological momentary assessment study in major depression

Suicidal behavior is associated with deficits in cognitive control; however, suicidal ideation (SI), a key precursor to suicidal behavior, has been less consistently linked to neuropsychological functioning. Additionally, no study to date has examined attentional control capacities in relation to variability in suicidal ideation, defined as fluctuation in SI intensity and duration across short periods of time. Prior research suggests that suicidal individuals with highly variable SI experience greater stress-responsive increases in SI and cortisol, potentially raising risk for suicidal behavior. Here, we examined attentional control capacities associated with SI variability and severity in ninety-five subjects with major depressive disorder. Variability and severity of SI and depressive affect were quantified using Ecological Momentary Assessment (EMA) over a 7-day period. Participants completed the Continuous Performance Task (CPT) and a computerized Stroop task for assessment of attentional control. EMA SI variability was associated with greater attentional interference on the Stroop task, and this was not accounted for by severity of SI, concurrently assessed depressive affect, or baseline depression. CPT performance was not related to SI variability or intensity. Findings highlight the utility of EMA methods in characterizing patterned experiences of SI and suggest that attentional control deficits may contribute to these characteristic patterns.

Resting-state functional connectivity of the amygdala in major depressive disorder with suicidal ideation

Suicide is a common issue among major depressive disorder (MDD) patients and suicidal ideation (SI) is the first step toward it. There are no definitive objective biomarkers of SI relative to MDD. In this study, a seed-based correlation analysis was performed among 36 MDD patients with SI, 66 MDD patients without SI (NSI), and 57 healthy controls (HCs) using amygdala resting-state functional connectivity (RSFC). Furthermore, the correlation between amygdala RSFC and clinical features was examined in the SI group. When compared to the NSI group, SI group exhibited increased RSFC between the left amygdala seed and left medial superior frontal gyrus (SFGmed) as well as left middle frontal gyrus (MFG). In turn, a decreased RSFC was observed between the left amygdala seed and the following brain regions including the left inferior parietal lobule (IPL), right precentral gyrus (PrCG), and left superior parietal lobule (SPL) in SI group compared to NSI group. Moreover, the SI group exhibited increased RSFC of the right amygdala with left middle temporal gyrus (MTG); In addition, the RSFC of the left amygdala with left MFG was negatively associated with learning and memory (VSM), speed of processing (SOP). The RSFC of the amygdala is distinct between MDD patients with SI and without SI. Our findings reveal the neurobiological characteristics of MDD with respect to SI and provide new clues regarding vulnerability to mental illness. It is necessary to carry out repeated and more longitudinal researches using multimodal approaches on SI in the future.

Suicide Ideation and Neurocognition Among 9- and 10-Year Old Children in the Adolescent Brain Cognitive Development (ABCD) Study

OBJECTIVE

During the past decade, the pediatric suicide rate has nearly tripled. Yet, little is known about suicide behavior (SB) in children. Identification of risk factors associated with SB during childhood may be critical to preventing future attempts. The purpose of this study was to examine the relationship between neurocognitive performance and suicide ideation (SI) in children.

METHOD

The present study utilized baseline data from 11,875 participants in the Adolescent Brain Cognitive Development (ABCD) study, a longitudinal study that follows 9- and 10-year-old children through late adolescence to examine factors that influence developmental trajectories. Suicidality was assessed by the Kiddie Schedule for Affective Disorder and Schizophrenia (KSADS) suicide module completed by the parent. Neurocognitive ability was assessed using the NIH Toolbox Cognition measures administered to the youth.

RESULTS

Children with a history of SI reported by their parent or concordant parent and youth report of SI demonstrated lower performance on the NIH Toolbox Picture Sequence Memory Test compared to children without SI. The difference in performance on the memory task remained significant when including demographic characteristics, family history of suicide, and internalizing symptoms in the model as covariates.

CONCLUSIONS

To our knowledge, this is the first study to identify decreased episodic memory in children with SI. These findings are similar to results from adult and adolescent studies which have reported decreased memory performance among suicide attempters. Deficits in episodic memory may impact a child's ability to problem-solve and generate potential future outcomes, which may increase the risk for SB. Early identification of memory deficits in children may inform suicide prevention and intervention efforts.Highlights6% of parents and children reported a history of active suicide ideation in children.Children with a history of suicide ideation had lower episodic memory performance.Early identification of memory deficits may inform suicide intervention efforts.

Inflammation biomarkers in suicide attempts and their relation to abuse, global functioning and cognition

OBJECTIVES

To explore the link between cytokines and suicide attempts and their relationship with the psychological aspects of this complex multifactorial phenomenon.

METHODS

96 participants, including 20 patients with a recent suicide attempt and diagnosis of Major Depression Disorder (MDD), 33 MDD patients with a lifetime history of suicide attempt, 23 non-attempter MDD patients, and 20 healthy controls underwent an assessment on depressive symptoms, global functioning, aggressive behaviour, presence of abuse and attention performance. Additionally, all participants had a blood extraction for IL-2, IL2-R, IL-4, IL-6, and TNF-α plasma levels analysis.

RESULTS

IL-6 levels were significantly different across groups (F(3,89)=3.690; p = 0.015), with higher concentrations in both recent (p = 0.04) and distant (p = 0.015) attempt in comparison to MDD non-attempters. IL-6 was associated with adult physical abuse (B = 2.591; p = 0.021), lower global functioning score (B = -0.512; p = 0.011), and poorer performance on attention (B = -0.897; p = 0.011).

CONCLUSIONS

Recent and distant suicidal behaviour is associated with elevated IL-6 levels, which may be influenced by stressful and traumatic experiences. Elevated concentrations of IL-6 could have a negative impact on attention, increasing suicide risk. More research is needed to clarify the role of cytokines in suicide-related features to explore novel treatments and more effective preventive interventions.

Differential Role of mGluR5 in Cognitive Processes in Posttraumatic Stress Disorder and Major Depression

Background

A robust literature supports the role of the metabotropic glutamate receptor type 5 (mGluR5) in cognitive functioning. mGluR5 is also implicated in the pathophysiology of posttraumatic stress disorder (PTSD) and major depressive disorder (MDD), which are characterized by cognitive alterations. However, the relationship between mGluR5 and cognition in MDD and PTSD has not yet been directly investigated. To address this gap, we examined the relationship between in vivo mGluR5 availability and cognition in PTSD, MDD, and matched healthy adults (HA).

Methods

Individuals with PTSD (N = 28) and MDD (N = 21), and HA (N = 28) were matched for age, gender, and smoking status. Participants completed 18F-FPEB positron emission tomography (PET) scan, psychiatric and cognitive assessments.

Results

Across models examining the relationship between mGluR5 availability and different domains of cognition across diagnostic groups, only the interaction of diagnosis*attention was significant (F 4,64 = 3.011, P = .024). Higher mGluR5 availability was associated with poorer attention in PTSD in 4 frontolimbic regions of interests (ROI's: OFC (r = -.441, P = .016), vmPFC (r = -.408, P = .028), dlPFC (r = -.421, P = .023), hippocampus (r = -.422, P = .025). By contrast, mGluR5 availability in the MDD group was positively related to Attention (ATTN) in the OFC (r = .590, P = .006), vmPFC (r = .653, P = .002), and dlPFC (r = .620, P = .004). Findings in the hippocampus for MDD followed the same pattern but did not survive correction for multiple comparisons (r = .480, P = .036). ATTN and mGluR5 availability were not significantly related in the HA group. Of note, in MANOVA analyses group*ATTN interaction results in the OFC did not survive multiple comparisons (P = .046). All other findings survived correction for multiple comparisons and remained significant when covarying for potential confounds (eg, depressed mood).

Conclusions

We observed a significant relationship between frontolimbic mGluR5 availability and performance on tests of attention in individuals with MDD and PTSD. This finding aligns with animal work showing dysregulation in mGluR5 in cognitive functioning, and differed as a function of diagnosis. Results suggest interventions targeting mGluR5 may help bolster cognitive difficulties, highlighting the importance of employing different mGluR5 directed treatment strategies in MDD and PTSD.

Implicit Cognition Tests for the Assessment of Suicide Risk: a Systematic Review

PURPOSE OF REVIEW

Suicide risk assessment is a challenge in clinical practice. Implicit measures may present with advantages with respect to explicit methods, and therefore may be useful for the assessment of suicide risk. We conducted a systematic review of 2 databases (PubMed and EMBASE) about implicit tests that measure suicide risk to explore their validity and reliability.

RECENT FINDINGS

Initial research revealed 321 articles. After the selection process, 31 articles were included in the review. The most death-related implicit cognition test used was the Death/Suicide Implicit association test (D/S IAT), followed by the Suicide Stroop Task. The Suicide Affect Misattribution Procedure (S-AMP) and the Death version of the Implicit Relational Assessment Procedure (D-IRAP) were also used. We found that the measures reviewed were generally valid for the assessment of past and future suicidal thoughts and behaviors, with statistically significant results regarding retrospective and prospective associations.

Development of Autonomic Nervous System Assays as Point-of-Care Tests to Supplement Clinical Judgment in Risk Assessment for Suicidal Behavior: A Review

PURPOSE OF REVIEW

A biomarker point-of-care (POC) test that supplements the psychiatric interview and improves detection of patients at risk for suicide would be of value, and assays of autonomic nervous system (ANS) activity would satisfy the logistical requirements for a POC test. We performed a selective review of the available literature of ANS assays related to risk for suicide.

RECENT FINDINGS

We searched PubMed and Web of Science with the strategy: "suicide OR suicidal" AND "electrodermal OR heart rate variability OR pupillometry OR pupillography." The search produced 119 items, 21 of which provided original data regarding ANS methods and suicide. These 21 studies included 6 for electrodermal activity, 14 for heart rate variability, and 1 for the pupillary light reflex. The 21 papers showed associations between ANS assays and suicide risk in a direction suggesting underlying hyperarousal in patients at risk for suicide. ANS assays show promise for future development as POC tests to supplement clinical decision making in estimating risk for suicide.

Association between neurocognitive functioning and suicide attempts in U.S. Army Soldiers

BACKGROUND

Suicide is a serious public health problem, including among U.S. Army personnel. There is great interest in discovering objective predictors of suicide and non-fatal suicidal behaviors. The current study examined the association between neurocognitive functioning and pre-military history of suicide attempts (SA) and post-enlistment onset of SA.

METHODS

New Soldiers reporting for Basic Combat Training (N = 38,507) completed a comprehensive computerized neurocognitive assessment battery and self-report questionnaires. A subset of Soldiers (n = 6216) completed a follow-up survey, including assessment of lifetime SA, 3-7 years later.

RESULTS

Six hundred eighty-nine Soldiers indicated lifetime SA at baseline and 210 Soldiers indicated new-onset SA at follow-up. Regression analyses, adjusted for demographic variables, revealed significant bivariate associations between neurocognitive performance on measures of sustained attention, impulsivity, working memory, and emotion recognition and lifetime SA at baseline. In a multivariable model including each of these measures as predictors, poorer impulse control and quicker response times on an emotion recognition measure were significantly and independently associated with increased odds of lifetime SA. A second model predicted new-onset SA at follow-up for Soldiers who did not indicate a history of SA at baseline. Poorer impulse control on a measure of sustained attention was predictive of new-onset SA.

LIMITATIONS

Effect sizes are small and of unlikely clinical predictive utility.

CONCLUSIONS

We simultaneously examined multiple neurocognitive domains as predictors of SA in a large, representative sample of new Army Soldiers. Impulsivity most strongly predicted past and future SA over and beyond other implicated cognitive-emotional domains.

Suicidal ideation and executive functioning in pediatric cancer

OBJECTIVE

Neurocognitive impairments and psychological distress are among the most common difficulties experienced by children treated for cancer. Elevated rates of suicidal ideation (SI) are documented among cancer survivors, and a link between neurocognitive deficits and SI is evident, yet the relationship between SI and pediatric cancer-related neurocognitive effects has not yet been studied.

PARTICIPANTS AND METHODS

Participants were 166 pediatric cancer patients (57.8% Brain Tumor, 31.3% leukemia, 10.8% other cancers) aged 6-23 (M = 11.57, SD = 3.82; 45.8% female) referred for neuropsychological surveillance. SI prevalence was measured by parent, teacher, or patient endorsement of self-harm related items on informant-report measures (e.g., the Child Behavior Checklist). Executive functioning (Behavior Rating Inventory of Executive Function), ADHD symptoms (ADHD Rating Scale), and performance-based measures were compared between those with SI and those without.

RESULTS

17.5% of pediatric cancer patients experienced SI, of which 44.7% had self-endorsement only, 58.5% parent-endorsement only, 20.6% teacher-endorsement only, and 24.1% had two endorsements. Those with SI had significantly greater impairments in global executive composite scores by both parent- and teacher-report (ps < 0.05). Parents of children with SI endorsed significantly more inattention symptoms (M = 6.10, SD = 15.48) than those without SI (M = 50.56, SD = 8.70; p < 0.01), but hyperactivity symptoms did not differ. Intellectual and executive function performance did not differ between those with and without SI (ps > 0.1).

CONCLUSIONS

An elevated number of children treated for cancer experience SI and related neurocognitive problems. Screening for SI and further assessment of the connection between executive functioning and SI in pediatric cancer populations is needed.

Saccadic Eye Movements in Elderly Depressed Patients With Suicidal Behaviors: An Exploratory Eye-Tracking Study

Suicidal behaviors (SBs) are often associated with impaired performance on neuropsychological executive functioning (EF) measures that encourage the development of more specific and reliable tools. Recent evidence could suggest that saccadic movement using eye tracking can provide reliable information on EF in depressive elderly. The aim of this study was to describe oculomotor performances in elderly depressed patients with SB. To achieve this aim, we compared saccadic eye movement (SEM) performances in elderly depressed patients (N = 24) with SB and with no SB in prosaccade (PS) and antisaccade (AS) tasks under the gap, step, and overlap conditions. All participants also underwent a complete neuropsychological battery. Performances were impaired in patients with SB who exhibited less corrected AS errors and longer time to correct them than patients with no SB. Moreover, both groups had a similar performance for PS latencies and correct AS. These preliminary results suggested higher cognitive inflexibility in suicidal patients compared to non-suicidal. This inflexibility may explain the difficulty of the depressed elderly in generating solutions to the resurgence of suicidal ideation (SI) to respond adequately to stressful environments. The assessment of eye movement parameters in depressed elderly patients may be a first step in identifying high-risk patients for suicide.

A qualitative systematic review of neurocognition in suicide ideators and attempters: Implications for cognitive-based psychotherapeutic interventions

BACKGROUND

Growing evidence suggests cognitive deficits may represent neurocognitive markers with predictive utility in identifying those at risk for suicide. Characterizing these deficits may offer the opportunity to develop targeted interventions.

AIM

The aim of this systematic qualitative review is to provide a synthesis of the published data on neurocognition in suicide ideators and attempters in order to clarify which neurocognitive targets may be most relevant to address using cognitive-based psychotherapeutic strategies in patients at risk for suicide.

RESULTS

A total of 63 studies met criteria for inclusion. The most consistent findings were in depressed suicide attempters, where deficits in executive subdomains of inhibition, selective attention and decision-making, as well as in working memory, were identified. In contrast, no clear pattern of neurocognitive deficits emerged from studies in suicide ideators across diagnoses.

CONCLUSIONS

More studies are needed to clarify the role of cognitive deficits in specific subtypes of individuals at risk for suicide. The findings are discussed in the context of promising research on cognitive remediation and other psychological interventions.

Attentional control may be modifiable with Mindfulness-Based Cognitive Therapy to Prevent Suicide

OBJECTIVE

To test whether Mindfulness-Based Cognitive Therapy to Prevent Suicide (MBCT-S) is associated with improvement in attentional control, an objective marker of suicide attempt.

METHOD

In the context of a randomized clinical trial targeting suicide risk in Veterans, computerized Stroop and emotion Stroop (E-Stroop) tasks were administered 3 times over 6-months follow-up to 135 high suicide risk Veterans. Seventy were randomized to receive MBCT-S in addition to enhanced treatment as usual (eTAU), and 65 were randomized to eTAU only. E-Stroop word types included positively- and negatively-valenced emotion, suicide, and combat-related words. Interference scores and mixed effects linear regression analyses were used.

RESULTS

Veterans receiving MBCT-S showed a more favorable trajectory of attentional control over time, as indicated by performance on two E-Stroop tasks. Combat-stress interference scores improved over time among Veterans in MBCT-S. Interference processing time for negative affective words deteriorated over time among Veterans receiving eTAU only.

CONCLUSIONS

MBCT-S may effectively target attentional control, and in particular reduce processing time during affective interference, in high suicide risk Veterans. Future studies to replicate these findings are warranted.

A multi-method assessment of attentional processes in chronic, treatment-resistant depression

Attentional deficits as well as attentional biases towards negative material are related to major depression and might maintain chronicity. However, studies investigating attentional deficits and attentional biases in chronic, treatment-resistant depressed are lacking. The aim of the current study was to compare measures of attentional deficits and attentional bias between chronic, treatment-resistant depressed outpatients and never-depressed control participants. Attentional deficits were assessed with the attentional control scale (ACS) and the Stroop Color naming task. Attentional bias was measured with the exogenous cueing task (ECT) and an emotional Stroop task. Chronic, treatment-resistant depressed patients (n = 80) showed significantly more attentional deficits than never-depressed controls (n = 113) on the ACS and Stroop color-naming task. However, in contrast with hypotheses, no differences were found between chronic, treatment-resistant depressed patients and never-depressed individuals on the ECT or emotional Stroop task. The current findings indicate that chronic, treatment-resistant depressed patients present attentional deficits. The results however question whether this patient group shows attentional biases for negative material. Future research should include comparisons of chronic, treatment-resistant and non-chronically depressed patients. If replicated, these current results might indicate that focusing on improving attentional deficits could be a more promising target for treatment than addressing attentional biases.

Cognition in Recent Suicide Attempts: Altered Executive Function

Background: Neuropsychological alterations can lead to inaccurate perception, interpretation, and response to environmental information, which could be a risk factor for suicide. Methods: Ninety-six subjects were recruited from the Psychiatry Department of the Araba University Hospital-Santiago, including 20 patients with a recent attempt and diagnosis of major depressive disorder (MDD) according to DSM-V, 33 MDD patients with history of attempted suicide, 23 non-attempter MDD patients, and 20 healthy controls. All participants underwent a clinical interview and neuropsychological assessment on the following cognitive domains: working memory, processing speed, decision-making, executive function, and attention. Backward multiple regressions were performed adjusting for significant confounding variables. For group comparisons, ANOVA and Bonferroni post-hoc tests were performed with a p < 0.05 significance level. Results: The patient groups did not differ regarding severity of depression and stressful events in the last 6 months. In comparison to healthy controls, depressed patients with lifetime suicide attempts had more general trauma (p = 0.003), emotional abuse (p = 0.003), emotional negligence (p = 0.006), and physical negligence (p = 0.009), and depressed patients with recent suicide attempts had experienced more child sexual abuse (p = 0.038). Regarding neuropsychological assessment, all patient groups performed significantly worse than did healthy controls in processing speed, decision-making, and attention. Comparisons between patient groups indicated that recent suicide attempters had poorer performance on executive function in comparison to both depressed lifetime attempters and depressed non-attempters (B = 0.296, p = 0.019, and B = 0.301, p = 0.028, respectively). Besides, women with recent attempts had slightly better scores on executive function than males. Regarding the rest of the cognitive domains, there were no significant differences between groups. Conclusion: Executive function performance is altered in recent suicide attempts. As impaired executive function can be risk factor for suicide, preventive interventions on suicide should focus on its assessment and rehabilitation.

Low MoCA performances correlate with suicidal ideation in late-life depression

Late-life depression remains an underdiagnosed clinical entity, mainly because the presence of cognitive impairment in the elderly leads clinicians to suspect dementia rather than depression. Our objective was to analyze the cognitive abilities of elderly depressed patients using the Montreal Cognitive Assessment (MoCA) in relation to the presence or absence of suicidal ideation. The MoCA, Beck Scale of Suicidal Ideation, Hamilton Anxiety Scale, and Hamilton Depression Scale were administered to 72 patients with a recent history of late life depression: 43 with suicidal ideation and 29 non-suicidal controls. The results show that suicidal patients demonstrated significantly worse performance on the MoCA total score and the delayed recall subtest in comparison to non-suicidal controls. In addition, after adjusting for age and depression, poorer performance on the MoCA total score correlated to the presence of suicidal ideation. We found that the MoCA total score is able to predict the presence of suicidal ideation in depressed elderly patients in a fair-to-good manner. As late-life depression is already established as a potential prodrome of dementia, longitudinal follow-up may determine whether depressed individuals with suicidal ideation are at higher risk of converting to dementia.

Investigating whether depressed youth exhibiting elevated C reactive protein perform worse on measures of executive functioning, verbal fluency and episodic memory in a large, population based sample of Dutch adolescents

Cognitive functioning is disrupted during a depressive episode and cognitive dysfunction persists when depression is in remission. A subtype of depressed individuals who exhibit elevated inflammatory biomarkers may be at particular risk for cognitive dysfunction. We examined whether an elevated inflammatory biomarker (C-reactive protein: CRP) in acute and/or remitted depression was associated with specific deficits in executive functioning, episodic memory, and verbal fluency. Data were drawn from a population-based sample of Dutch adolescents (N = 1066; 46% male) recruited at the age of 11 and followed over the course of eight years. We tested whether adolescents with either, (i) a history of depression (Wave 1-3) or (ii) current depression (Wave 4), and elevated levels of C-reactive protein measured in blood at Wave 3 performed worse on cognitive assessments at Wave 4. Eight measures of cognitive functioning were hypothesized to load on to one of three dimensions of cognitive functioning (executive functioning, episodic memory, and verbal fluency) within a structural equation model framework. Higher levels of CRP were associated with worse future executive functioning in adolescents with and without current/prior depression. A current depression diagnosis also was associated with worse executive functioning. There was consistent evidence linking low socioeconomic status and health-related covariates (high body mass index/sedentary behavior) with worse performance across multiple measures of cognitive functioning and, importantly, the association of depression/CRP and executive functioning was no longer significant when controlling for these covariates. Future studies may benefit from investigating whether specific depressogenic behaviors (e.g., sedentary behavior/substance use) mediate a relationship between depression and worse executive functioning, potentially via a prospective pathway through elevated inflammation.

Association Between Elevated Depressive Symptoms and Cognitive Function Moderated by APOE4 Status: Framingham Offspring Study

BACKGROUND

Depression and Apolipoprotein E4 (APOE4) are associated with decreased cognitive function and differences in brain structure.

OBJECTIVE

This study investigated whether APOE4 status moderates the association between elevated depressive symptoms, cognitive function, and brain structure.

METHODS

Stroke- and dementia-free participants (n = 1,968) underwent neuropsychological evaluation, brain MRI, and depression screening. Linear and logistic regression was used to examine all associations. Secondary analyses were performed using interaction terms to assess effect modification by APOE4 status.

RESULTS

Elevated depressive symptoms were associated with lower cognitive performance in several domains. In stratified analyses, elevated depressive symptoms were associated with poorer visual short- and long-term memory performance for APOE4 + participants. Elevated depressive symptoms were not associated with any brain structure in this study sample.

CONCLUSION

Elevated depressive symptoms impact cognitive function in non-demented individuals. Having the APOE4 allele may exacerbate the deleterious effects of elevated depressive symptoms on visual memory performance. Screening for elevated depressive symptoms in both research studies and clinical practice may be warranted to avoid false positive identification of neurodegeneration, particularly among those who are APOE4 + .

Childhood cognitive skill trajectories and suicide by mid-adulthood: an investigation of the 1958 British Birth Cohort

BACKGROUND

Poor cognitive abilities and low intellectual quotient (IQ) are associated with an increased risk of suicide attempts and suicide mortality. However, knowledge of how this association develops across the life-course is limited. Our study aims to establish whether individuals who died by suicide by mid-adulthood are distinguishable by their child-to-adolescence cognitive trajectories.

METHODS

Participants were from the 1958 British Birth Cohort and were assessed for academic performance at ages 7, 11, and 16 and intelligence at 11 years. Suicides occurring by September 2012 were identified from linked national death certificates. We compared mean mathematics and reading abilities and rate of change across 7-16 years for individuals who died by suicide v. those still alive, with and without adjustment for potential early-life confounding factors. Analyses were based on 14 505 participants.

RESULTS

Fifty-five participants (48 males) had died by suicide by age 54 years. While males who died by suicide did not differ from participants still alive in reading scores at age 7 [effect size (g) = -0.04, p = 0.759], their reading scores had a less steep improvement up to age 16 compared to other participants. Adjustments for early-life confounding factors explained these differences. A similar pattern was observed for mathematics scores. There was no difference between individuals who died by suicide v. participants still alive on intelligence at 11 years.

CONCLUSIONS

While no differences in tests of academic performance and IQ were observed, individuals who died by suicide had a less steep improvement in reading abilities over time compared to same-age peers.

Active and Passive Attentional Processing in Adolescent Suicide Attempters: An Event-Related Potential Study

INTRODUCTION

Suicide is the second leading cause of death among adolescents. Suicidal behavior is associated with impairments in attention. Attention can be directed toward relevant events in the environment either actively, under voluntary control, or passively, by external salient events. The extent to which the risk for suicidal behavior affects active and passive attention is largely unknown.

METHODS

Event-related potentials (ERPs) were recorded while 14 adolescents with acute suicidal behavior and 14 healthy controls performed an auditory 3-stimulus oddball task. The task consisted of standard (80%), target (10%), and novel (10%) stimuli. The participants were instructed to press a button upon presentation of the target. The novel stimuli were unexpected and irrelevant to the target detection task.

RESULTS

Accuracy of target detection was slightly but significantly reduced in the suicidal group. There were no significant differences in the amplitude of the target-N2 or -P3b between groups. There was a slight, but nonsignificant, increase in the amplitude of the novel-N2 and -P3 in the suicidal group.

CONCLUSIONS

This is the first study to explore both passive and controlled aspects of attention using ERPs in adolescents with acute suicidal behavior. Although there were no significant ERP group differences, this is an important step in identifying objective markers of suicide risk among adolescents.

Suicidal behaviour and cognition: A systematic review with special focus on prefrontal deficits

BACKGROUND

Suicide is a major health concern worldwide, thus, identifying risk factors would enable a more comprehensive understanding and prevention of this behaviour. Neuropsychological alterations could lead to difficulties in interpreting and managing life events resulting in a higher risk of suicide.

METHOD

A systematic literature search from 2000 to 2020 was performed in Medline (Pubmed), Web of Science, SciELO Citation Index, PsycInfo, PsycArticles and Cochrane Library databases regarding studies comparing cognition of attempters versus non-attempters that share same psychiatric diagnosis.

RESULTS

1.885 patients diagnosed with an Affective Disorder (n = 1512) and Schizophrenia/ Schizoaffective Disorder (n = 373) were included. In general comparison, attention was found to be clearly dysfunctional. Regarding diagnosis, patients with Schizophrenia and previous history of suicidal behaviour showed a poorer performance in executive function. Patients with current symptoms of an Affective Disorder and a previous history of suicidal attempt had poorer performance in attention and executive function. Similarly, euthymic affective patients with history of suicidal behaviour had worse decision-making, attention and executive function performance compared to euthymic non-attempters.

LIMITATIONS

The number of papers included in this review is limited to the few studies using non-attempter clinically-matched control group and therefore results regarding diagnosis, symptomatology and time of the attempt are modest and contradictory.

CONCLUSIONS

Patients who have attempted suicide have a poorer neuropsychological functioning than non-attempters with a similar psychiatric disorder in attention and executive function. These alterations increase vulnerability for suicide.

Association between family history of suicide attempt and neurocognitive functioning in community youth

BACKGROUND

Suicidal behavior is highly familial. Neurocognitive deficits have been proposed as an endophenotype for suicide risk that may contribute to the familial transmission of suicide. Yet, there is a lack of research on the neurocognitive functioning of first-degree biological relatives of suicide attempters. The aim of the present study is to conduct the largest investigation to date of neurocognitive functioning in community youth with a family history of a fatal or nonfatal suicide attempt (FH).

METHODS

Participants aged 8-21 years from the Philadelphia Neurodevelopmental Cohort completed detailed clinical and neurocognitive evaluations. A subsample of 501 participants with a FH was matched to a comparison group of 3,006 participants without a family history of suicide attempt (no-FH) on age, sex, race, and lifetime depression.

RESULTS

After adjusting for multiple comparisons and including relevant clinical and demographic covariates, youth with a FH had significantly lower executive function factor scores (F[1,3432] = 6.63, p = .010) and performed worse on individual tests of attention (F[1,3382] = 7.08, p = .008) and language reasoning (F[1,3387] = 5.12, p = .024) than no-FH youth.

CONCLUSIONS

Youth with a FH show small differences in executive function, attention, and language reasoning compared to youth without a FH. Further research is warranted to investigate neurocognitive functioning as an endophenotype for suicide risk. Implications for the prevention and treatment of suicidal behaviors are discussed.

Toxoplasma gondii, Suicidal Behavior, and Intermediate Phenotypes for Suicidal Behavior

Within the general literature on infections and suicidal behavior, studies on Toxoplasma gondii (T. gondii) occupy a central position. This is related to the parasite's neurotropism, high prevalence of chronic infection, as well as specific and non-specific behavioral alterations in rodents that lead to increased risk taking, which are recapitulated in humans by T. gondii's associations with suicidal behavior, as well as trait impulsivity and aggression, mental illness and traffic accidents. This paper is a detailed review of the associations between T. gondii serology and suicidal behavior, a field of study that started 15 years ago with our publication of associations between T. gondii IgG serology and suicidal behavior in persons with mood disorders. This "legacy" article presents, chronologically, our primary studies in individuals with mood disorders and schizophrenia in Germany, recent attempters in Sweden, and in a large cohort of mothers in Denmark. Then, it reviews findings from all three meta-analyses published to date, confirming our reported associations and overall consistent in effect size [ranging between 39 and 57% elevation of odds of suicide attempt in T. gondii immunoglobulin (IgG) positives]. Finally, the article introduces certain links between T. gondii and biomarkers previously associated with suicidal behavior (kynurenines, phenylalanine/tyrosine), intermediate phenotypes of suicidal behavior (impulsivity, aggression) and state-dependent suicide risk factors (hopelessness/dysphoria, sleep impairment). In sum, an abundance of evidence supports a positive link between suicide attempts (but not suicidal ideation) and T. gondii IgG (but not IgM) seropositivity and serointensity. Trait impulsivity and aggression, endophenotypes of suicidal behavior have also been positively associated with T. gondii seropositivity in both the psychiatrically healthy as well as in patients with Intermittent Explosive Disorder. Yet, causality has not been demonstrated. Thus, randomized interventional studies are necessary to advance causal inferences and, if causality is confirmed, to provide hope that an etiological treatment for a distinct subgroup of individuals at an increased risk for suicide could emerge.

Cognitive Control in Suicide Ideators and Suicide Attempters

There is a need to understand more of the risk factors involved in the process from suicide ideation to suicide attempt. Cognitive control processes may be important factors in assessing vulnerability to suicide. A version of the Stroop procedure, Delis-Kaplan Executive Function System (D-KEFS) Color-Word Interference Test (CWIT) and Behavior Rating Inventory of Executive Function (BRIEF-A) were used in this study to test attention control and cognitive shift, as well as to assess everyday executive function of 98 acute suicidal psychiatric patients. The Columbia Suicide History Form (CSHF) was used to identify a group of suicide ideators and suicide attempters. Results showed that suicide attempters scored lower on attention control than suicide ideators who had no history of attempted suicide. The self-report in the BRIEF-A inventory did not reflect any cognitive differences between suicide ideators and suicide attempters. A logistic regression analysis showed that a poorer attention control score was associated with the suicide attempt group, whereas a poorer cognitive shift score was associated with the suicide ideation group. The results found in this study suggest that suicide attempters may struggle with control of attention or inhibiting competing responses but not with cognitive flexibility.

The Role of Sociodemographic, Clinical and Neuropsychological Variables in Suicide Attempts in Depressed Adolescents

INTRODUCTION

In this study, we aimed to evaluate the relationship between sociodemographic, clinical and neuropsychological variables and suicide attempts by comparing adolescents with Major Depressive Disorder (MDD) with and without suicide attempt.

METHOD

30 adolescents with and without suicide attempt were included in this study. Sociodemographic and Clinical Data Form, Schedule for Affective Disorders and Schizophrenia for School-Age Children--Present and Lifetime Version (K-SADS-PL), The Children Depression Inventory (CDI), Beck Hopelessness Scale (BHS), Barratt Impulsivity Scale (BIS) and neuropsychological tests (Go/NoGo test, Stroop test Wisconsin Card Sorting Test) was applied to participants.

RESULTS

Depressed adolescents with suicide attempt compared to adolescents without suicide attempt; motor and total impulsivity scores in BIS-11, commission errors in Go/NoGo test which measure motor inhibition, completion time and errors in Stroop 5 which measure interference inhibition and scores of perseveration in Winsconsin Card Sorting Test (WCST) which measure cognitive inhibition were found to be higher. Family history of suicide attempt (OR: 5.87), commission errors (OR: 1.37), perseverative errors (OR: 1.09) ve total impulsivity (OR: 1.05) were remained in the logistic regression model.

CONCLUSION

Results of this study suggested that family history of suicide attempt was the most important factor predicting suicide attempt in adolescents with depression. Other factors predicting suicide attempt were executive dysfunction and impulsivity.

Using resting-state intrinsic network connectivity to identify suicide risk in mood disorders

BACKGROUND

Little is known about the neural substrates of suicide risk in mood disorders. Improving the identification of biomarkers of suicide risk, as indicated by a history of suicide-related behavior (SB), could lead to more targeted treatments to reduce risk.

METHODS

Participants were 18 young adults with a mood disorder with a history of SB (as indicated by endorsing a past suicide attempt), 60 with a mood disorder with a history of suicidal ideation (SI) but not SB, 52 with a mood disorder with no history of SI or SB (MD), and 82 healthy comparison participants (HC). Resting-state functional connectivity within and between intrinsic neural networks, including cognitive control network (CCN), salience and emotion network (SEN), and default mode network (DMN), was compared between groups.

RESULTS

Several fronto-parietal regions (k > 57, p < 0.005) were identified in which individuals with SB demonstrated distinct patterns of connectivity within (in the CCN) and across networks (CCN-SEN and CCN-DMN). Connectivity with some of these same regions also distinguished the SB group when participants were re-scanned after 1-4 months. Extracted data defined SB group membership with good accuracy, sensitivity, and specificity (79-88%).

CONCLUSIONS

These results suggest that individuals with a history of SB in the context of mood disorders may show reliably distinct patterns of intrinsic network connectivity, even when compared to those with mood disorders without SB. Resting-state fMRI is a promising tool for identifying subtypes of patients with mood disorders who may be at risk for suicidal behavior.

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.

Towards the objective assessment of suicidal states: Some neurocognitive deficits may be temporally related to suicide attempt

Neurocognitive detection of suicidal states has the potential to significantly advance objective risk assessment. This goal requires establishing that neurocognitive deficits fluctuate around the time of a suicide attempt. The current study therefore evaluated whether neurocognitive performance is temporally related to suicide attempt, in a sample at highrisk for suicide (n = 141). Evaluations consisted of a clinician-administered interview, self-report questionnaires, and neurocognitive tasks assessing response inhibition, attentional control, and memory recognition. Analyses examined whether neurocognitive scores significantly differed according to the following temporal suicide attempt categories: (a) past-week attempt; (b) past-year attempt (not in past week); and (c) no past-year attempt. Univariate results showed that response inhibition and memory recognition were significantly related to suicide attempt recency. Post-hoc pairwise tests showed that participants with a past-week suicide attempt showed greater impairments than those without a past-year attempt. Multivariate tests showed the same pattern of results, adjusting for age, suicide attempts prior to past year, mood disturbance, and suicidal ideation. These results show that neurocognitive assessment of response inhibition and memory recognition shows sensitivity to the recency of a suicide attempt. While future prospective studies are needed, results suggest that phasic neurocognitive deficits may serve as objective markers of short-term suicide risk.

Impact of GRIK4 gene polymorphisms on cognitive dysfunction in patients with major depression

An increasing body of research has focused on the functions of the glutamate receptor ionotropic kainate 4 (GRIK4) gene in treatment for depression, memory, as well as neurodegenerative diseases. It is widely recognized that major depressive disorder (MDD) patients often display cognitive dysfunctions, which do not strictly correlate with the severity of depressive symptoms, and in some individuals persist after clinical remission. However, little is known regarding the particular role of GRIK4 in cognitive functions of patients suffering from a MDD. The current study therefore sought to examine the impact of GRIK4 polymorphism on cognitive functions in MDD patients. A total of 217 MDD patients participated in this study. Their depressive severity was determined with the 17-item Hamilton Depression Rating Scale, and cognitive functions were evaluated using the Stroop Neuropsychological Screening Test, tests of visual reproduction and immediate logical memory, and the verbal fluency test (VFT). All patients were genotyped to determine GRIK4 polymorphisms. Results of VFT revealed statistical differences among all single-nucleotide polymorphism (SNP) genotypes. In the Stroop-color-word test, only rs6589847 was discovered to be statistically different. No significant difference was found in the Stroop-color task scores, the visual reproduction test, or the immediate logical memory test. GRIK4 polymorphism exerted a significant effect on long-term memory retrieval and selective attention, but did not affect immediate memory.

Sleep problems and suicide risk in youth: A systematic review, developmental framework, and implications for hospital treatment

OBJECTIVE

Sleep problems are transdiagnostic symptoms that confer significant risk for suicidal thoughts and behaviors (STBs) in adults. However, less is known about the sleep-STB association in adolescence-a developmental period when rates of STBs increase drastically, and sleep problems may be particularly pernicious. This article provides a systematic review of research on the sleep-STB association in youth, an overview of changes in sleep regulation during adolescence that may make sleep problems particularly detrimental for youth, and a discussion of the clinical implications of the sleep-STB association for hospitalized youth.

METHOD

The systematic review included all longitudinal studies in which sleep problems were examined as prospective predictors of STBs in adolescents (aged 10-24 years). The search was conducted on December 1, 2017 using PsychINFO, PubMed, and Web of Science databases.

RESULTS

Ten studies qualified for inclusion in this review. Of these, seven studies found at least one type of sleep problem significantly predicted a STB outcome.

CONCLUSIONS

Although findings are mixed, growing research suggests that sleep problems may be a unique risk factor for STBs in youth. Sleep problems may be particularly important intervention target because they are easily assessed across healthcare settings and are amenable to treatment.

From depressive symptoms to suicide risk: Roles of sense of belongingness and acquired capability for suicide in patients with mental disorders

In order to prevent suicides in patients with mental disorders, it was critical to recognize the risk factors and explore the mechanism. Based on depressive symptoms, which were common in patients with mental disorders in consolidation period in China, we constructed a moderated mediating model under the framework of Integrated Motivational-Volitional Model of suicidal behaviour, and examined the mechanism of how depressive symptoms, thwarted belongingness, and acquired capability for suicide influenced suicide risk. In this study, data were collected from 164 patients through four questionnaires, and analyzed with PROCESS macro for SPSS (Hayes, 2008). The result showed that in the predictive effects of depressive symptoms on suicide risk, thwarted belongingness was a partial mediating variable, while acquired capability for suicide played a moderating role in the partial mediating model. Specifically, the predictive effects of depressive symptoms and thwarted belongingness, both as motivation variables, on suicide risk both occurred in the case of the high acquired capability of suicide, which was a volition variable. The research pointed out the interdependence of depressive symptoms and a sense of belongingness, and clarified the critical role of acquired capability for suicide. The integrated perspective could enhance the interpretation of reality, and enlightened those carrying out the practice of suicide intervention to patients with mental disorders.

A qualitative systematic review of suicide behavior using the cognitive systems domain of the research domain criteria (RDoC) framework

Neurocognitive deficits are associated with both suicide behavior (SB) and psychiatric disorders. Application of a transdiagnostic framework to identify neurocognitive commonalities of SB may clarify important risk factors of SB across psychiatric disorders. The aim of this study was to conduct a qualitative systematic literature review of SB using the Research Domain Criteria (RDoC) Cognitive Systems framework to determine if cognitive deficits exist independently of psychiatric disorders in SB. The following six constructs that encompass the Cognitive Systems domain were assessed: 1) Attention, 2) Cognitive Control, 3) Declarative Memory, 4) Language, 5) Perception, and 6) Working Memory. A total of 1386 abstracts were identified and 74 studies met the inclusion criteria for this review. The majority of studies reviewed (65%) had significant differences in cognition between individuals with and without SB. Seventy-nine percent of studies with a patient control group showed significant cognitive deficits in SB groups. Deficits in cognitive control were associated with SB and had the greatest percentage of studies with significant main findings. Use of the RDoC cognitive systems framework to evaluate SB revealed that cognitive deficits may be a transdiagnostic risk factor for SB, especially alterations in cognitive control.

Reducing Suicidal Ideation Through Insomnia Treatment (REST-IT): A Randomized Clinical Trial

OBJECTIVE

The authors sought to determine whether targeted treatment of insomnia with controlled-release zolpidem (zolpidem-CR) in suicidal adults with insomnia would provide a reduction in suicidal ideation superior to placebo.

METHODS

Reducing Suicidal Ideation Through Insomnia Treatment was an 8-week three-site double-blind placebo-controlled parallel-group randomized controlled trial of zolpidem-CR hypnotic therapy compared with placebo, in conjunction with an open-label selective serotonin reuptake inhibitor. Participants were medication-free 18- to 65-year-olds with major depressive disorder, insomnia, and suicidal ideation. Suicidal ideation was the main outcome, measured first by the Scale for Suicide Ideation and second by the Columbia-Suicide Severity Rating Scale (C-SSRS).

RESULTS

A total of 103 participants were randomly assigned to receive zolpidem-CR (N=51) or placebo (N=52) (64 women and 39 men; mean age=40.5 years). Zolpidem-CR had a robust anti-insomnia effect, especially in patients with the most severe insomnia symptoms. No significant treatment effect was observed on the Scale for Suicide Ideation (least squares mean estimate=-0.56, SE=0.83, 95% CI=-2.19, 1.08), but the reduction in scores was significantly positively related to improvement in insomnia after accounting for the effect of other depression symptoms. The C-SSRS indicated that zolpidem-CR had a significant treatment effect (least squares mean estimate=-0.26, SE=0.12, 95% CI=-0.50, -0.02). The advantage for zolpidem-CR in reducing suicidal ideation on the C-SSRS was greater in patients with more severe insomnia. No deaths or suicide attempts occurred.

CONCLUSIONS

Although the results do not support the routine prescription of hypnotic medication for mitigating suicidal ideation in all depressed outpatients with insomnia, they suggest that coprescription of a hypnotic during initiation of an antidepressant may be beneficial in suicidal outpatients, especially in patients with severe insomnia.

Frontal Alpha Asymmetry Correlates with Suicidal Behavior in Major Depressive Disorder

Objective

Based on the constant associations made between major depressive disorder (MDD) and alpha asymmetry, and MDD and suicide, this study aimed to examine the relationship between frontal alpha asymmetry and suicide in MDD patients.

Methods

Sixty-six MDD patients, of whom fifteen were male and fifty-one were female, were recruited. Independent groups were created based on the median score of frontal alpha asymmetry: the left dominant (LD) group and the right dominant (RD) group. The alpha band (8‒12 Hz) and its sub-bands (i.e., low alpha band: 8‒10 Hz; high alpha band: 10‒12 Hz) were of interest. Source level alpha asymmetry was calculated as well.

Results

Suicidal behavior was positively correlated with the asymmetry indices of the low alpha band and the alpha band in the LD group and that of the high alpha band in the RD group. Source level analysis revealed positive correlations between suicidal behavior and the asymmetry index of the low alpha band in the LD group.

Conclusion

Frontal alpha asymmetry, especially that of the low alpha band, might reflect the cognitive deficits associated with suicidal behaviors in MDD patients.