Soluble interleukin 2 receptor levels, temperament and character in formerly depressed suicide attempters compared with normal controls

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.

Suicide attempts are associated with activated immune-inflammatory, nitro-oxidative, and neurotoxic pathways: A systematic review and meta-analysis

BACKGROUND

Suicide attempts (SA) frequently occur in patients with mood disorders and schizophrenia, which are both accompanied by activated immune-inflammatory and nitro-oxidative (IO&NS) pathways.

METHODS

We searched PubMed, Google Scholar, and Web of Science, for articles published from inception until February 1, 2021. We included studies that compared blood biomarkers in psychiatric patients with (SA+) and without SA (SA-) and heathy controls and we combined different IO&NS biomarkers into immune, inflammatory, and neurotoxic profiles and used meta-analysis (random-effect model with restricted maximum-likelihood) to delineate effect sizes with 95% confidence interval (CI).

FINDINGS

Our search included 51 studies comprising 4.945 SA+ patients and 24.148 controls. We stratified the control group into healthy controls and SA- patients. SA+ patients showed significantly (p<0.001) increased immune activation (SMD: 1.044; CI: 0.599, 1.489), inflammation (SMD: 1.109; CI: 0.505, 1.714), neurotoxicity (SMD: 0.879; CI: 0.465, 1.293), and lowered neuroprotection (SMD: 0.648; CI: 0.354, 0.941) as compared with healthy controls. When compared with SA- patients, those with SA+ showed significant (p<0.001) immune activation (SMD: 0.290; CI: 0.183, 0.397), inflammation (SMD: 0.311; CI: 0.191, 0.432), and neurotoxicity (SMD: 0.315; CI: 0.198, 0.432), and lowered neuroprotection (SMD: 0.341; CI: 0.167, 0.515). Patients with current, but not lifetime, SA showed significant (p<0.001) levels of inflammation and neurotoxicity as compared with controls.

CONCLUSIONS

Patients with immune activation are at a higher risk of SA which may be explained by increased neurotoxicity due to inflammation and nitro-oxidative stress. This meta-analysis discovered new biomarkers of SA and therapeutic targets to treat individuals with SA.

The role of gene polymorphisms, and analysis of peripheral and central levels of interleukins in suicidal behavior: A systematic review

In terms of the physiological characteristics of suicidal behavior (SB) disorder, an increase inflammation response has been reported in these individuals. Therefore, the pro-inflammatory and anti-inflammatory activities of interleukins are adequate markers to research in order to understand the pathogenesis of SB. For that reason, the aim of this systematic review was to evaluate the role of interleukins in individuals with suicidal behavior disorder. A systematic search was performed in PubMed, Scopus and EBSCO databases up to July 2019. We used the words "interleukin" AND "suicide", "interleukin" AND "suicidal", and "IL-". Articles where interleukins concentrations were measured in individuals with SB and/or genetic studies addressing interleukins genes variants as possible markers to SB were included. A total of 54 articles were included. Articles that measured interleukin levels comprised 1111 cases and 1588 controls; whereas the genetic studies comprised 3082 cases and 5148 controls. These studies evaluated the concentrations of IL-1β, IL-2, IL-3, IL-4, IL-5, IL-6, IL-8, IL-10, sIL-2R in serum, plasma. The pro-inflammatory interleukins concentrations were higher in cases than in controls; however, we observed heterogeneity in the measurements and sample sources. Whereas, 9 polymorphisms of IL-1α, IL-1β, IL-6, IL-1β-8 genes were analyzed in association with suicide behavior disorder, though no conclusive outcomes were attained. Our results suggest that individuals with suicide risk undergo continuous stress that could trigger the release and circulation of pro-inflammatory interleukins and therefore their concentration in plasma. However, more studies are necessary in order to reach conclusively outcomes.

Temperament traits in suicidal and non-suicidal mood disorder patients in Taiwan

Suicide is a major social and clinical problem in Asia. Although studies have suggested that personality traits are possible risk factors for suicide, no study has been conducted among Chinese to compare the temperament traits of suicidal and non-suicidal mood disorder patients with those of healthy controls. This study compared temperament traits of two patient groups, those with a mood disorder who have attempted suicide (n=204), and those with a mood disorder who have not attempted suicide (n=160), and compared the traits of these patients to those of healthy controls (n=178), assessed by Cloninger's Tridimensional Personality Questionnaire and the Brown-Goodwin Aggression Inventory. Patients with suicidal attempts had significantly higher novelty seeking and aggression scores than healthy controls and patients without suicidal attempts. Two groups of patients with mood disorder had significantly higher harm avoidance scores than the healthy controls. However, patients with suicidal attempts did not have higher harm avoidance scores than patients without suicidal attempts. This study confirms findings that harm avoidance and mood disorder are related, and extends them by suggesting that those with a mood disorder and suicide attempts have higher novelty seeking and lifetime aggression scores than those without suicidal attempt, either patients or healthy controls.

The role of cytokines in the pathophysiology of suicidal behavior

OBJECTIVE

Immune dysregulation has been implicated in depression and other psychiatric disorders. What is less clear is how immune dysregulation can affect risk of suicidal behavior. We reviewed the scientific literature concerning cytokines related to suicidal ideation, suicidal behavior and suicide, and surveyed clinical and neurobiological factors associated with cytokine levels that may modulate effects of inflammation on suicide risk.

METHODS

We searched PubMed, Embase, Scopus and PsycINFO for relevant studies published from 1980 through February, 2015. Papers were included if they were written in English and focused on cytokine measurements in patients with suicidal behaviors.

RESULTS

The literature search yielded 22 studies concerning cytokines and suicidal ideation, suicide attempts or suicide completion. The most consistent finding was elevated interleukin (IL)-6, found in 8 out of 14 studies, in CSF, blood, and postmortem brain. In one study, IL-6 in CSF was also found to be higher in violent than nonviolent attempters and to correlate with future suicide completion. Low plasma IL-2 was observed in 2 studies of suicide attempters, while divergent results were seen for tumor necrosis factor (TNF)-α, interferon (IFN)-γ, transforming growth factor (TGF)-β, IL-4, and soluble Il-2 receptors.

CONCLUSIONS

Given the complexity suggested by the heterogenous cytokine findings, putative mediators and moderators of inflammation on suicidal behavior merit further study. Elevated IL-6 was the most robust cytokine finding, associated with suicidal ideation and both nonfatal suicide attempts and suicides. Future studies should evaluate the predictive value of high IL-6, consider how this may alter brain function to impact suicidal behavior, and explore the potential beneficial effects of reducing IL-6 on suicide risk.

Meta-Analysis of Cytokines and Chemokines in Suicidality: Distinguishing Suicidal Versus Nonsuicidal Patients

BACKGROUND

Major psychiatric disorders are associated with inflammation. Aberrant cytokine and chemokine levels have been associated with psychiatric disorders and suicidal behavior. We performed a meta-analysis of cytokine and chemokine levels in patients with versus without suicidality and patients with suicidality versus healthy controls.

METHODS

We identified articles by searching MEDLINE, PsycINFO, and Thomson Reuters Web of Knowledge databases and the reference lists of identified studies.

RESULTS

Study inclusion criteria were met by 18 studies comprising 583 patients with suicidality, 315 patients without suicidality, and 845 healthy control subjects. Levels of interleukin (IL)-1β and IL-6 were significantly increased in blood and postmortem brain samples of patients with suicidality compared with both patients without suicidality and healthy control subjects (p < .05 for each). In vitro IL-2 production by peripheral blood mononuclear cells was significantly decreased in patients with suicidality compared with both patients without suicidality and healthy controls (p < .01 for each). Cerebrospinal fluid levels of IL-8 were significantly decreased in patients with suicidality versus control subjects (p < .05).

CONCLUSIONS

We found evidence for aberrant cytokine levels in blood, cerebrospinal fluid, and postmortem brain samples of patients with suicidality. Levels of IL-1β and IL-6 were most robustly associated with suicidality, and these cytokines may help distinguish suicidal from nonsuicidal patients. Rigorously designed longitudinal studies are needed to evaluate these associations further.

A meta-analysis of cytokines in suicidal behavior

BACKGROUND

We conducted the first meta-analysis of studies comparing the plasma and CSF concentrations of cytokines in suicidal patients vs. non-suicidal patients or healthy controls.

METHODS

We searched Medline, Web of Science, and PsycINFO from 1965 to November 2014 for relevant studies. Manual searches of references and unpublished data were also included. Suicidal patients included severe suicide ideators and suicide attempters.

RESULTS

Eleven articles were available for the meta-analysis, for a total sample size of 494 suicidal patients, 497 non-suicidal patients and 398 healthy controls. Levels of 6 independent plasma cytokines (IL2, IL6, TNFalpha, IFNgamma, IL4, TGFbeta) were meta-analyzed for plasma studies comparing suicidal vs. both controls. IL8 level was meta-analyzed for cerebrospinal fluid studies comparing suicidal patients with healthy controls. We reported with medium effect size, that suicidal patients had: (1) lower IL2 plasma levels than both non-suicidal patients and healthy controls (medium effect size); (2) lower IL4 and higher TGFbeta plasma levels than healthy controls.

CONCLUSION

Our results promote the hypothesis of altered inflammatory markers in suicidal patients, for both pro-inflammatory (IL2) and anti-inflammatory (IL4 and TGFbeta) cytokines.

Relationship of temperament and character in remitted depressed patients with suicidal ideation and suicide attempts--results from the CRESCEND study

The aim of this study was to evaluate the Temperament and Character Inventory (TCI) scores of a sample of Korean patients with remitted depression who had attempted suicide and reported suicidal ideation and to compare their scores with those of remitted depressed patients without suicidal ideation. Adult depression patients who had completed 12 weeks of follow-up (N = 138) were divided into three groups: patients with a history of suicide attempts (N = 23); patients with current suicidal ideation (N = 59); and patients without current suicidal ideation (N = 56). After controlling for covariates, no significant differences were found among the three groups on any measure of temperament or character except self-directedness and self-transcendence. The self-transcendence scores of the lifetime suicide-attempt group were significantly higher compared with those of the suicidal-ideation group; post hoc analysis revealed that self-directedness was significantly lower in the suicide-attempt group compared with the non-suicidal group. The results from the present study suggest that remitted depression patients with a history of suicide attempts do not differ from non-attempters in temperament, but do differ in certain character traits.

Influence of differentially expressed genes from suicide post-mortem study on personality traits as endophenotypes on healthy subjects and suicide attempters

Although a genetic contribution to the complex aetiology of suicidal behaviour has been suggested since many years, the attempt to identify specific genes related to suicide has led to contrasting results. In a post-mortem study on suicide, we previously detected several differentially expressed genes which, however, have not been subsequently associated with suicidal behaviour, or only nominally. Therefore, personality traits may represent good intermediate endophenotypes. Our primary aim was to investigate the potential modulation of several single-nucleotide polymorphisms (SNPs) of the same previously investigated genes (S100A13, EFEMP1, PCDHB5, PDGFRB, CDCA7L, SCN2B, PTPRR, MLC1 and ZFP36) on personality traits, as measured with the Temperament and Character Inventory (TCI), in a German sample composed of 287 healthy subjects (males: 123, 42.9 %; mean age: 45.2 ± 14.9 years) and in 111 psychiatric patients who attempted suicide (males: 43, 38.6 %; mean age: 39.2 ± 13.6 years). Multivariate analysis of covariance was used to test possible influence of single SNPs on TCI scores. Genotypic, allelic and haplotypic analyses have been performed. Controlling for sex, age and educational level, genotypic analyses showed a modulation of EFEMP1 rs960993 and rs2903838 polymorphisms on both harm avoidance and self-directedness in healthy subjects. Interestingly, we could replicate these associations in haploblocks within controls (p < 0.0001) and in the independent sample of suicide attempters for harm avoidance (p < 0.00001), a phenotype highly associated with suicidal behaviour. This study suggests that EFEMP1 SNPs, never investigated in association with suicidal behaviour and related personality, could be involved in its modulation in healthy subjects as well as in suicide attempters.

Personality traits associated with suicidal behaviors in patients with depression: the CRESCEND study

The aim of the current study was to identify personality traits associated with suicidal behavior in patients with depression. Of the 1183 patients screened for an observational cohort study of depression, 334 (28.2%) who completed the Temperament and Character Inventory (TCI) were included in these analyses. To minimize the effect of current mood state, the TCI was performed 12 weeks after initiation of treatment, and we adjusted for the severity of depression. Of the 344 participants, 59 had a lifetime history of at least one suicide attempt, 37 had a lifetime history of multiple suicide attempts, and 5 attempted suicide during the 12-week study period. At baseline, patients with a lifetime history of at least one suicide attempt, a lifetime history of multiple suicide attempts, and a suicide attempt during the study period expressed more serious current suicidal ideation than did those without such a history, despite the absence of differences among the groups in the severity of depressive and anxiety symptoms. Of the seven personality scales of the TCI, lower scores on the self-directedness scale of the character dimension were associated with a history of at least one suicide attempt (OR [95% CI], 0.91 [0.87-0.96]; p<0.001), a history of multiple suicide attempts (0.91 [0.86-0.97]; p=0.003), and suicide attempts during study period (0.80 [0.69-0.94]; p=0.006). These findings suggest that depressed patients with a history of suicidal behavior differ from non-attempters with regard to personality traits, especially the character dimension of self-directedness. It is noteworthy that this result emerged after controlling for the effect of current mood state.

A pilot genome wide association and gene expression array study of suicide with and without major depression

OBJECTIVES

Suicide is partly heritable but the responsible genes have not been identified. We conducted a gene-centric, low coverage single nucleotide polymorphism (SNP) pilot genome-wide association study (GWAS) seeking new candidate regions in suicides with and without depression, combined with gene expression assay of brain tissue.

METHODS

Ninety-nine Caucasian subjects, including 68 who completed suicide and 31 who died suddenly from other causes, were genotyped postmortem using GeneChip® Mapping 50K Xba. Clinical data were obtained from relatives. SNPs with Hardy-Weinberg equilibrium P values below 0.001 were excluded from analysis. Illumina chip expression arrays assayed the transcriptome in prefrontal cortex in a drug-free subgroup.

RESULTS

GWAS analysis (cutoff P < 0.001) yielded 58 SNPs, 22 of them in or near 19 known genes, with risk allele-associated odds ratios between 2.7 and 6.9. Diagnosis of mood disorder did not explain the associations. Some of the SNPs matched into four functional groups in gene ontology. Gene expression in the prefrontal and the anterior cingulate cortex for these 19 genes was measured on a separate, though overlapping, sample of suicides and seven of 19 genes showed altered expression in suicides as compared with controls, especially in immune system related genes.

CONCLUSIONS

Matching GWAS findings with expression data assesses functional effect of new candidate genes in suicide, and is an alternative form of confirmation or replication study. Results highlight a role for neuroimmunological effects in suicidal behaviour.

Temperament personality profiles in suicidal behaviour: an investigation of associated demographic, clinical and genetic factors

BACKGROUND

Personality traits have been suggested as possible risk factors for suicidal behaviours. Cloninger's model of personality (TCI), given its neurobiological background, might provide an ideal tool for the identification of dimensions associated with suicide attempt.

METHODS

A number of 1333 suicide attempters and 589 non-suicide attempters suffering from different DSM-IV Axis I disorders were assessed using either the temperament and character inventory (TCI) or the tridimensional personality questionnaire (TPQ), as well as other self-report questionnaires evaluating dimensions associated with suicidal behaviour, such as impulsivity and anger traits. The severity of suicide attempts and the methods used were also assessed. Subjects were genotyped for polymorphisms within the key genes involved in monoaminergic pathways and the HPA axis.

RESULTS

Compared with non-suicide attempters, suicide attempters scored higher for harm avoidance (HA) and novelty seeking (NS), and lower for self-directedness (SD). The difference was independent of Axis I disorders. Higher HA and NS scores were associated with a greater severity of suicidal behaviour. A multivariate model showed that HA was the single temperamental dimension independently related to suicide attempt history, beside impulsivity and anger-related traits. The genetic factors investigated did not play a significant role in modulating these temperamental dimensions.

LIMITATIONS

The TCI was available for only half of the sample.

CONCLUSIONS

Early detection of subjects displaying high HA and low SD, associated with high impulsivity and poor anger control, may help to prevent suicidal behaviours. Physicians should therefore be aware of these risk factors so that they can offer the best primary care intervention.

Temperament and character traits in patients with bipolar disorder and associations with attempted suicide

OBJECTIVE

This study was intended to investigate temperament and character traits in bipolar disorder patients with or without a history of attempted suicide.

METHODS

One hundred nineteen patients diagnosed with euthymic bipolar disorder based on Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision, and with no accompanying Axis I and II comorbidity, and 103 healthy controls were included. Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Axis I and II disorders were used to exclude Axis I and II comorbidity. Temperament and character traits of bipolar patients with a history attempted suicide (25.2%, n = 30) or without (74.8%, n = 89) and of the healthy volunteers were determined using the Temperament and Character Inventory. The association between current suicide ideation and temperament and character traits was also examined.

RESULTS

Bipolar patients with or without a history of attempted suicide had higher harm avoidance (HA) scores compared with the healthy controls. Persistence scores of bipolar patients with no history of attempted suicide were lower than those of the healthy controls. Self-directedness (SD) scores of the bipolar patients with a history of attempted suicide were lower than those of patients with no such history. Self-transcendence scores of bipolar patients with no history of attempted suicide were lower than those of both the healthy controls and of those patients with a history of attempted suicide. A positive correlation was determined between current suicidal ideation scale scores and HA, and a negative correlation between SD and cooperativeness was determined.

CONCLUSIONS

High harm avoidance may be a temperament trait specific to bipolar disorder patients. However, it may not be correlated with attempted suicide in such patients. These may have low persistence, high SD and low self-transcendence temperament and character traits that protect against attempted suicide. Harm avoidance, SD, and cooperativeness may be correlated with current suicidal ideation.

Temperament and character personality profile in relation to suicide attempts in patients with schizophrenia

INTRODUCTION

Schizophrenia is associated with a significant risk of suicide, and suicide still remains one of the main causes of death in schizophrenic patients. Beside classic risk factors for suicidality, temperament and character traits have been researched and considered as risk factors for suicidal behavior in recent years.

METHOD

Subjects were 94 patients with schizophrenia who were under treatment. All patients were in a stable phase of the illness. Patients with lifetime suicide attempt (n = 46) and without suicidal attempt (n = 48) were compared with each other in terms of temperament and character traits by using the Temperament and Character Inventory.

RESULTS

Harm avoidance and persistence scores were higher in suicidal schizophrenic patients compared with nonsuicidal schizophrenic patients. The scores of self-directedness and cooperativeness were lower in suicidal schizophrenic patients compared with nonsuicidal schizophrenic patients. These 4 variables remained significant predictors of lifetime suicidal attempts in a logistic regression model.

CONCLUSION

To the best of our knowledge, the present study is the first that specifically compares schizophrenic patients with and without suicidal behavior by the Cloninger temperament and character model. Our data indicate that schizophrenic patients will show a greater risk for suicide according to certain personality configurations. However, to establish causal relationships between personality and suicidality in schizophrenia, longitudinal studies are warranted within a multifactorial interactive framework of biologic and clinical variables.

Temperament and character in euthymic major depressive disorder patients: the effect of previous suicide attempts and psychotic mood episodes

OBJECTIVE

The purpose of this study was to examine personality traits of patients with major depressive disorder and explore the possible connections between personality and clinical and sociodemographic variables.

METHODS

The sociodemographic and clinical properties of 80 patients with major depression, who were euthymic according to Hamilton Depression Scale scores, were recorded. Their personality was evaluated by using Temperament and Character Inventory and results were compared with 80 age- and sex-matched healthy controls. We used general linear model analysis to evaluate the manner in which the variables contributed to TCI scores.

RESULTS

Remitted depressive patients scored significantly lower on on self-directedness and higher on harm avoidance than HC. Previous suicide attempts had a main effect only on harm avoidance while previous psychotic mood episodes were significantly associated with novelty seeking, self-directedness and cooperativeness. With respect to numeric clinical variables, only duration of illness was significantly and negatively correlated with NS and RD scores.

CONCLUSION

Patients with euthymic major depressive disorder may have significantly different personality traits than the normal population, and patients with different clinical and sociodemographic characteristics may show different personality patterns. In addition, assessment of major depressed patients by means of the Temperament and Character Inventory may be helpful to get a deeper insight into those personality traits underlying suicidality and the emergence of psychotic mood episode.

Depression is an inflammatory disease, but cell-mediated immune activation is the key component of depression

The first findings that depression is characterized by cell-mediated immune activation and inflammation were published between 1990-1993 (Maes et al.). Recently, it was reported that--based on meta-analysis results--depression is an inflammatory disorder because the plasma levels of two cytokines are increased, i.e. interleukin-(IL)-6 and tumor necrosis factor-α (TNFα). The same meta-analysis found that plasma IL-2 and interferon-(IFN)γ levels are not altered in depression, suggesting that there is no T cell activation in that illness. The present paper reviews the body of evidence that depression is accompanied by cell-mediated immune activation. The findings include: increased serum levels of the soluble IL-2 receptor (sIL-2R) and the sCD8 molecule; increased numbers and percentages of T cells bearing T cell activation markers, such as CD2+CD25+, CD3+CD25+, and HLA-DR+; increased stimulated production of IFNγ; higher neopterin and sTNFR-1 or sTNFR-2 levels; induction of indoleamine 2,3-dioxygenase (IDO) with lowered levels of plasma tryptophan and increased levels of tryptophan catabolites along the IDO pathway (TRYCATs); and glucocorticoid resistance in immune cells. Interferon-α (IFNα)-based immunotherapy shows that baseline and IFNα-induced activation of T cells, IDO activity and TRYCAT formation are related to the development of IFNα-induced depressive symptoms. Animal models of depression show that a cell-mediated immune response is related to the development of depression-like behavior. Antidepressants and mood stabilizers suppress different aspects of cell-mediated immunity and rather specifically target IFNγ production. This review shows that inflammation and cell-mediated immune activation are key factors in depression.

Suicidality in male prisoners: influence of childhood adversity mediated by dimensions of personality

This study aims to study the influence of childhood adversity on suicidal behavior in male prisoners. Including a random sample of 899 male prisoners (French National Mental Health Prison Survey, 2003), this paper studied suicidal ideations and suicide attempts using MINI criteria, and personality using Temperament and Character Inventory. Risk factors of suicidality were examined, and structural equations studied the influence of childhood trauma on suicidality, mediated by personality dimensions. The prisoners reported high levels of childhood adversity. More than a third reported recent suicidal ideations. Childhood adversity and dimensions of personality were associated with suicidality. Structural equations showed that childhood adversity was positively associated with suicidality, mediated by poor dimensions of character (affective stability, self-cooperativeness, and self-transcendence). In conclusion, these results confirm the importance of screening and treatment of childhood trauma among male prisoners. They suggest the importance to study dimensions of personality and tailor treatment to specific needs.

Temperament and character personality profile in relation to suicidal ideation and suicide attempts in major depressed patients

To prevent suicidal behaviour, it is important to better understand those personality traits associated with suicidal ideation and suicide attempts. A sample of 394 consecutive major depressed outpatients admitted to Bonn University Hospital was subdivided into three groups: Lifetime suicide attempters (N=32; 8.1%), suicide ideators (N=133) and patients without suicide ideation (N=229). Psychodiagnostic measures embraced the Temperament and Character Inventory (TCI), the Symptom Checklist-90-R and the Hamilton Depression Rating Scale. Suicide attempters and ideators showed higher scores on emotional distress and depression. Analysis of covariance (covariates: age, gender, depression) revealed that suicide attempters score higher on the temperament dimension harm avoidance compared with non-attempters. Suicide ideators could be distinguished from non-ideators by character dimensions in terms of lower self-directedness and higher self-transcendence. Our findings suggest that high harm avoidance is a personality trait associated with suicide attempt in major depression, whereas low self-directedness and high self-transcendence are related to suicidal ideation. As temperament dimensions represent the "emotional core" and character dimensions the "cognitive core" of personality, we discuss whether Cloninger's psychobiological model might be helpful to distinguish between non-suicide ideators, patients who do think about suicide, and patients initiating suicidal behaviour.

Personality and attempted suicide. Analysis of anger, aggression and impulsivity

Suicide is one of the leading causes of death worldwide, mortality from suicide being approximately 2%. Attempted suicide appears to be a major risk factor for suicide completion. Anger, aggression and impulsivity are personality traits associated with suicide attempt. In this study we analysed a part of a previously reported sample in order to test anger, impulsivity and temperament/character scales as predictors of aggression and self-aggression in suicide attempters and to compare anger- and aggression-related traits between impulsive and premeditated suicide attempts as well as between violent and non-violent suicide methods. One-hundred-eleven consecutively admitted inpatients with a lifetime history of attempted suicide were assessed for anger (State-Trait Anger Expression Inventory, STAXI), aggression (Questionnaire for Measuring Factors of Aggression, FAF) and temperament/character (Temperament and Character Inventory, TCI). Higher aggression scores, as measured by FAF, were predicted by being male, meeting criteria for borderline personality disorder and having higher angry temperament scores as assessed by STAXI; low cooperativeness was also associated with aggression but not after controlling for STAXI scales. TCI dimensions associated with self-aggression were high harm avoidance, high impulsivity and low self-directedness; state anger, inwardly directed anger and inhibition of aggression were also predictors of self-aggression. In conclusion, impulsivity and harm avoidance have emerged as temperament dimensions independently associated with self-aggressive tendencies in personality. Such interactions could explain the correlation between temperament and suicidality but further research is needed. Anger and self-directedness appear to have some effects on suicide attempt.

Elevated cytokine expression in the orbitofrontal cortex of victims of suicide

OBJECTIVE

Based on the reported association between cytokines with depression and suicide, and evidence of increased markers of inflammation in the brain of suicide victims, the present study examined the expression of cytokines in the orbitofrontal cortex of suicide victims.

METHOD

In a postmortem sample obtained from the Brodman area 11 of suicides (n = 34) and controls (n = 17), real-time RT-PCR was used to compare the expression of mRNA species for tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1 beta, 4, 5, 6, and 13.

RESULTS

Increased expression of IL-4 was found in women suicide victims and IL-13 in men suicide victims. Elevated but not significant cytokine expression was also observed for TNF-alpha in women suicide victims.

CONCLUSION

To our knowledge, these results provide the first evidence of the presence of mRNA transcripts of type 2 T-helper cytokines in the human orbitofrontal cortex and their increased expression in the brain of suicides.