Cognitive Control in Suicide Ideators and Suicide Attempters

Suicidal risk in patients with aggression in schizophrenia: a systematic review

Introduction

Suicide represents the primary risk factor for mortality among individuals diagnosed with schizophrenia, with a mortality rate that is 10 times higher than that observed in the general population. In the study of individuals who have committed suicide, some exhibited a high risk of aggression and impulsivity, which permitted the consideration of these indicators as predictors of suicide risk. The extant literature contains a number of debates concerning diverse conceptualizations of aggression and impulsivity in the context of suicidal behavior. The present study examined the levels of verbal and physical aggression in individuals diagnosed with schizophrenia, finding that 43% exhibited verbal aggression and 24% physical aggression, levels that are significantly higher than those observed in the general population. Concurrently, an analysis of the psycho-emotional state of patients with suicidal behavior in the anamnesis reveals an indication that the suppression of emotions (including aggression) and the avoidance of harm may result in suicide. This finding is at odds with the previously mentioned results, and consequently, the present review sought to assess the impact of aggressive behavior on suicide risk in patients diagnosed with schizophrenia.

Methods

The search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The literature search was conducted in PubMed, Cochrane Library, PsychINFO and Mendeley Data. The search terms used were "aggress*" and "suicid*" or "autoaggress*" and "schizophrenia*". The search was limited to papers published between 2009 and 2024 (the last 15 years), and the search was continued until November 2024. This systematic review has been registered in PROSPERO (CRD42024628033).

Results

A total of 1,364 articles were identified, 295 of which were duplicates. Following a thorough review, 1,046 articles that did not align with the title and abstract were excluded from the analysis. During the literature search, 23 articles were read in full, of which eight studies met the inclusion criteria. A total of eight studies provided information on the effect of aggressive behavior on suicide in patients with schizophrenia. Of these, six studies demonstrated a positive association between aggression and suicidal behavior or employed a logistic regression model in which the risk of aggression increased the risk of suicide and vice versa. Conversely, two studies revealed no association between suicide risk and aggression.

Conclusions

Patients with a documented history of suicide attempts and aggressive behavior are considered to be at risk of suicide, thus emphasizing the necessity for preventive measures to be implemented for this cohort of patients. However, the conclusion regarding the influence of aggressive behavior on increased suicide risk may not be entirely accurate and may not reflect the true extent of the problem, due to the significant number of methodological inaccuracies and discrepancies in the design of the studies included in the review.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/view/CRD42024628033, identifier CRD42024628033.

Cognitive control impairment in suicide behaviors: what do we know? A systematic review and meta-analysis of Stroop in suicide behaviors

BACKGROUND

Suicidal behavior results from a complex interplay between stressful events and vulnerability factors, including cognitive deficits. Poorer performance on the Stroop task, a measure of cognitive control, has been associated with suicidal behavior in numerous studies. The objective was to conduct an updated systematic review of the literature on the Stroop task as a neuropsychological test of vulnerability to suicidal acts in patients with mood and other psychiatric disorders, while also looking at how the type (classic versus emotional) or the version (paper or computerized) of the Stroop task, as well as the characteristics of the patient (clinical population, age, sex) moderated the Stroop effect.

METHODS

A search on Medline, Embase, PsycInfo databases, and article references was performed. 53 studies (6781 participants) met the selection criteria. Interference time and errors of the Stroop Test were assessed in at least 3 studies to be analyzed. Moderators, such as the type (classic versus emotional) of the Stroop task and the characteristics of the patient (clinical population, age, sex) were also assessed.

RESULTS

Interference time on Stroop performance was lower in suicide attempters than in patient controls (g = 0.20; 95%CI [0.10-0.30]) and healthy controls (g = 0.79; 95 % CI [0.29-1.29]), with patient controls scoring lower than healthy controls (g = -0.63; 95%CI [-1.01-0.25]). This was moderated by age and having a mood disorder. In terms of interference errors, suicide attempters performed worse than healthy controls (g = 0.57; 95%CI [0.01-1.15]) but did not perform differently from patient controls (g = 0.20; 95 % CI [-0.06-0.45]). Patient controls also did not score differently than healthy controls (g = -0.18; 95 % CI [-0.54-0.18]). There was a significant moderation effect for the type (i.e., original Stroop task) and version (i.e., paper format) of the Stroop task, and for some characteristics of the patient (i.e., older patients and having a mood disorder).

CONCLUSIONS

Cognitive control impairment was associated with a history of suicidal behavior in patients, especially in older populations and those with mood disorders, however this result was moderated by outcome measure (interference time vs. errors), the type (i.e., original Stroop task) and the version (i.e., paper format) of the Stroop task. Cognitive control processes may be an important factor of suicidal vulnerability. Choosing the right neurocognitive test in the right population to detect suicide vulnerability is important direction for future research.

Childhood Maltreatment, Executive Function, and Suicide Attempts in Adolescents

Evidence suggests that child maltreatment is a risk factor for adolescent suicidal behavior. However, the differential influence of distinct forms of child maltreatment on adolescent suicide attempts is understudied and the factors that might exacerbate or ameliorate these associations warrant attention. We examined the associations between two distinct forms of child maltreatment (threat and deprivation) and suicide attempt history, and investigated whether executive function domains moderated these associations. Participants were 119 adolescents (M = 15.24, SD = 1.46, 72.3% female) recruited from an inpatient psychiatric hospital during hospitalization for suicidal thoughts and behaviors. Results indicated that the executive function domains of initiation, shifting, and planning/organization moderated the associations between threat and suicide attempt history. Associations between threat and suicide attempt history were significant only when initiation and shifting T-scores were lower (OR = 1.22, p = .03 and OR = 1.32, p = .01, respectively). The association between threat and suicide attempt history trended toward significance when planning/organization T-scores were lower (OR = 1.15, p = .10). None of the executive function domains moderated the link between deprivation and suicide attempt history. Findings highlight the need for research investigating whether initiation, shifting, and planning/organization might be amendable to intervention in the context of threat-related child maltreatment.

Reduced attentional control in individuals with a history of suicide attempts compared to those with suicidal ideation: Results from a systematic review and meta-analysis

BACKGROUND

Neurocognitive profiles may be especially useful to identify factors that facilitate transitioning from contemplating suicide to attempting suicide. Generally, those who attempt suicide show greater disruptions in neurocognitive ability compared to those who think about suicide but do not proceed to attempt. The goal of this systematic review and meta-analysis is to test whether this pattern is observed with attentional control.

METHODS

We systematically searched PubMed, PsychINFO, CINAHL, and Google Scholar to find pertinent studies. All included studies compared attentional functioning using neutral stimuli. Each sample featured adults with a history of suicidal ideation (SI) and no history of suicide attempts (SA) compared to those with a history of SA.

RESULTS

We identified 15 studies with 32 effect sizes (N = 931; n = 506 with SI only; n = 425 with SA). SA groups, compared to SI groups, exhibited worse accuracy yet similar reaction time, suggesting a comparatively blunted speed-accuracy tradeoff. Relative to SI, SA groups performed worse on Stroop-like and Go/NoGo tasks. SA performed better than SI on Trail Making Test B, but not A.

LIMITATIONS

There were few available studies. Most samples were small. We did not differentiate current vs. past SI or high vs. low lethality SA. Only English and Spanish language articles were included.

CONCLUSIONS

Disrupted attentional control may convey risk for transitioning to SA from SI. More work is needed to determine which components of attention are most associated with suicide risk.

Reactive control in suicide ideators and attempters: An examination of the congruency sequence effect in cognitive and emotional Simon tasks

Reactive control is the cognitive ability to adjust thoughts and behaviors when encountering conflict. We investigated how this ability to manage conflict and stress distinguishes suicidal from nonsuicidal individuals. The hypothesis was that suicidal individuals would show poorer reactive control when faced with conflict generated by emotional than neutral stimuli. Hence, individuals with a lifetime history of suicide ideation or attempt and nonsuicidal controls were tested in cognitive and emotional Simon tasks. We examined the congruency sequence effect (CSE) in the Simon tasks as an indication of the efficiency of reactive control in resolving conflict. Whereas controls demonstrated significant CSEs in both tasks, suicide attempters showed a significant CSE in the cognitive task but not in the emotional task. Suicide ideators, on the other hand, displayed marginally significant CSEs in both tasks. Comparing groups with pairwise comparison demonstrated that the difference in CSE was significant only in the emotional task between attempters and controls. Our findings of attempters' inefficiency in adjusting reactive control during the emotional task reflect cognitive inflexibility in coping with conflicting situations during which suicidal individuals become vulnerable to suicide attempts in states of negative emotion.

Revisiting the work-suicide link: renewed evidence and models of analysis in workplace contexts

Suicide is a priority public health problem for the World Health Organization. It is a multifactorial phenomenon, for which there is no effective strategy for prevention and reduction. The scientific knowledge generated has not paid much attention to the differentiating role of work and employment on the phenomenon of suicide. This article first presents Abrutyn's recent conceptual model of suicide, which has a psychosocial, holistic and integrated approach. Based on this model, it examines the most recent and solid evidence and trends linking working conditions and phenomenon of suicide, identifying the most relevant findings in work stress theories. It concludes by pointing out avenues of development for a more holistic and ecological understanding of suicide.

Association between the epigenetic lifespan predictor GrimAge and history of suicide attempt in bipolar disorder

Bipolar disorder (BD) has been previously associated with premature mortality and aging, including acceleration of epigenetic aging. Suicide attempts (SA) are greatly elevated in BD and are associated with decreased lifespan, biological aging, and poorer clinical outcomes. We investigated the relationship between GrimAge, an epigenetic clock trained on time-to-death and associated with mortality and lifespan, and SA in two independent cohorts of BD individuals (discovery cohort - controls (n = 50), BD individuals with (n = 77, BD/SA) and without (n = 67, BD/non-SA) lifetime history of SA; replication cohort - BD/SA (n = 48) and BD/non-SA (n = 47)). An acceleration index for the GrimAge clock (GrimAgeAccel) was computed from blood DNA methylation (DNAm) and compared between groups with multiple general linear models. Differences in epigenetic aging from the discovery cohort were validated in the independent replication cohort. In the discovery cohort, controls, BD/non-SA, and BD/SA significantly differed on GrimAgeAccel (F = 5.424, p = 0.005), with the highest GrimAgeAccel in BD/SA (p = 0.004, BD/SA vs. controls). Within the BD individuals, BD/non-SA and BD/SA differed on GrimAgeAccel in both cohorts (p = 0.008) after covariate adjustment. Finally, DNAm-based surrogates revealed possible involvement of plasminogen activator inhibitor 1, leptin, and smoking pack-years in driving accelerated epigenetic aging. These findings pair with existing evidence that not only BD, but also SA, may be associated with an accelerated biological aging and provide putative biological mechanisms for morbidity and premature mortality in this population.

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.

Alpha-beta decoupling relevant to inhibition deficits leads to suicide attempt in major depressive disorder

BACKGROUND

One devastating outcome of major depressive disorder (MDD) is high suicidality, especially for patients with suicide attempt (SA). Evidence indicated that SA may be strongly associated with inhibitory control deficits. We hypothesized that the inhibition function deficits of patient with SA might be underpinned by abnormal neuronal oscillations.

METHODS

Our study recruited 111 subjects including 74 patients and 37 controls, who performed a GO/NOGO task during magnetoencephalography recording. Time-frequency-representations and phase-amplitude-coupling were measured for the brain circuits involved in the inhibitory function. Phase-slope-indexes were calculated between regions to determine the direction of power flow.

RESULTS

Significant increased reaction time and decreased judgment accuracy were observed in SA group. During the perception stage of GO task (approximately 125 ms), SA group manifested elevated alpha power in ventral prefrontal cortex (VPFC) and attenuated beta power in dorsal anterior cingulate (dACC) compared with other groups (p < 0.01). In the processing stage of NOGO task (approximately 300 ms), they showed decreased beta power in VPFC and increased alpha power in dACC (p < 0.01). Alpha-beta decoupling during both tasks was observed in SA group. Furthermore, the decoupling from VPFC to dACC under NOGO tasks was significantly correlated with suicide risk level.

LIMITATIONS

The number of participants was relatively small, and psychological elements were not involved in current study.

CONCLUSION

Dysregulated oscillatory activities of dACC and VPFC suggested deficits in execution and inhibition functions triggering high suicide risks. The alpha-beta decoupling from VPFC to dACC could be served as a neuro-electrophysiological biomarker for identifying potential suicide risk.

Correlation between suicidal ideation and emotional memory in adolescents with depressive disorder

This study explored the differences in emotional memory between adolescents with and without suicidal ideation. Fifty adolescents with depression and suicidal ideation, 36 with depression but no suicidal ideation, and 41 healthy controls rated the emotional valence of positive, neutral, and negative pictures. Then, the recognition of the images was evaluated 72 h later. Adolescents with suicidal ideation reported more negative emotional valence scores for positive and neutral pictures and were significantly less likely to recognize negative pictures than were those without suicidal ideation. The performance of adolescents with suicidal ideation on the negative picture recognition test was closely related to anxiety, depression severity, and intensity of suicidal ideation. The negative bias toward neutral stimuli and cognitive impairment may be important risk factors for adolescents with suicidal ideation. Improving emotional memory via targeted management approaches may help young people with suicidal ideation.