The Cardiff sib-pair study: suicidal ideation in depressed and healthy subjects and their siblings

Impulsivity in Major Depressive Disorder Patients with Suicidal Ideation: Event-related Potentials in a GoNogo Task

Objective

: Suicidal ideation is one of the strongest predictors of suicide, and its relevance to impulsivity in depressed patients has been accumulated. Furthermore, high impulsivity patients show the attenuation of the Nogo amplitude in the GoNogo event-related potential (ERP). The purpose of the current study is to determine the correlation of Nogo ERP to the suicidal ideation depending on the condition of its presence or absence in major depressive disorder (MDD) patients.

Methods

: A total 162 participants (104 patients with suicidal ideation, 31 patients without suicidal ideation, and 27 healthy controls) were recruited, and performed GoNogo tasks during the electroencephalogram measurement. Depression, anxiety, suicidal ideation and impulsivity were assessed by self-rating scales. The clinical measures, behavioral data and Nogo ERP were compared among groups.

Results

: The MDD with suicidal ideation (SI) group showed significantly decreased Nogo P3 amplitudes compared to MDD without SI (Fz and Cz electrodes) and control group (all electrodes). The MDD with SI group also had significantly low accuracy of both Go and Nogo trails, compared to the MDD without group. The Nogo P3 amplitudes showed the negative relation to the scores of impulsivity, depression, anxiety and SI.

Conclusion

: Our results concluded that the Nogo P3 ERP amplitude was decreased in MDD patients with SI compared to MDD patients without SI and controls. These findings suggest that the decreased Nogo P3 amplitude is the one of the candidate biomarker for impulsivity in MDD patients to evaluating SI.

The role of personality dimensions, depressive symptoms and other psychosocial variables in predicting postpartum suicidal ideation: a cohort study

Suicidability has been associated with neuroticism and psychoticism, but its role during perinatal period has not been analyzed. We explore the association between personality dimensions, depressive symptoms, and other psychosocial variables in postpartum suicidal ideation. A cohort of 1795 healthy Spanish women from the general population was assessed for suicidal ideation (EPDS-Item10) in early postpartum, 8 and 32 weeks postpartum. Sociodemographic, obstetric, and reproductive variables, psychiatric history, social support, stressful life-events during pregnancy, depressive symptoms (EPDS), and the Eysenck's personality dimensions (EPQ-RS) were also assessed at baseline. A major depressive episode (DSM-IV) was confirmed in women with EPDS>10 at follow-up assessments. Descriptive, bivariate, and multivariate analyses were conducted. Adjusted logistic regression analysis was reported as odds ratio (ORs) with 95% confidence intervals (CIs). Seven percent of mothers reported suicidal ideation during the first 8 months postpartum. Sixty-two percent of women with suicidal ideation had a major depressive episode at 8 weeks, and 70% at 32 weeks postpartum. Neuroticism and psychoticism predicted suicidal ideation throughout the first 2 weeks after delivery (OR, 1.03; 95%CI 1.01-1.06; and OR, 1.03; 95%CI 1.01-1.05 respectively). Early postpartum depressive symptoms (OR 1.2; 95%CI 1.11-1.26), personal psychiatric history (OR 2.1; 95%CI 1.33-3.27), and stressful life events during pregnancy (OR 1.88; 95%CI 1.12-3.16) also emerged as predictors of postpartum suicidal ideation. Analysis of women for postpartum suicidal ideation should include not only psychiatric symptoms but also psychosocial assessment (i.e., covering psychiatric history, stressful events, or long-standing personality vulnerabilities) in order to identify those in need of early psychosocial or psychiatric care.

Relationship between Internet addiction, susceptible personality traits, and suicidal and self-harm ideation in Chinese adolescent students

BACKGROUND AND AIMS

Internet addiction (IA) is common among young students. This study aimed to examine the influence and mechanisms of IA and susceptible personality traits on the impact of suicidal ideation in adolescent students in China.

METHODS

This cross-sectional study (09/2012-09/2015) used stratified cluster sampling with "school type" for stratification; 136,266 students from 63 schools completed the questionnaire. Logistic regression analysis was performed to estimate the effect of IA (Young's Internet Addiction Test) and susceptible personality (Barratt impulsiveness scale, Buss & Perry Aggression Questionnaire; and Eysenck Personality Questionnaire-R Short Scale) on suicidal ideation (Scale of Suicidal Ideation).

RESULTS

Suicidal ideation was observed in 20,218 (14.77%) of the students, and IA was detected in 28,836 (21.16%) subjects. Compared with those without IA, students with IA had a higher prevalence of suicidal ideation (P < 0.0001). No planning impulsiveness had a predictive effect on suicidal ideation in the impulsive personality trait, while in the aggressive personality trait, hostility and self-aggression had a predictive effect on suicidal ideation (all P < 0.0001). High psychoticism and neuroticism were impact factors for suicidal ideation, but extroversion was a protective factor (all P < 0.0001).

DISCUSSION

These results highlight the importance of assessing personality traits and reducing IA as a possible means of lessening suicidal ideation. Susceptible personality (such as high psychoticism, high neuroticism, and low extroversion) play a prominent role in influencing the probability of having suicidal behavior among those recently exposed to IA.

CONCLUSIONS

IA and susceptible personality traits were significantly correlated with suicidal and self-harm ideation among adolescent students.

Antidepressant-resistant depression is characterized by reduced short- and long-interval cortical inhibition

BACKGROUND

Major depressive disorder (MDD) is highly heterogeneous and can be classified as treatment-resistant depression (TRD) or antidepressant-responsive depression (non-TRD) based on patients' responses to antidepressant treatment. Methods for distinguishing between TRD and non-TRD are critical clinical concerns. Deficits of cortical inhibition (CI) have been reported to play an influential role in the pathophysiology of MDD. Whether TRD patients' CI is more impaired than that of non-TRD patients remains unclear.

METHODS

Paired-pulse transcranial magnetic stimulation (ppTMS) was used to measure cortical inhibitory function including GABAA- and GABAB-receptor-related CI and cortical excitatory function including glutamate-receptor-related intracortical facilitation (ICF). We recruited 36 healthy controls (HC) and 36 patients with MDD (non-TRD, n = 16; TRD, n = 20). All participants received evaluations for depression severity and ppTMS examinations. Non-TRD patients received an additional ppTMS examination after 3 months of treatment with the SSRI escitalopram.

RESULTS

Patients with TRD exhibited reduced short-interval intracortical inhibition (SICI) and long-interval intracortical inhibition (LICI), as shown by abnormally higher estimates, than those with non-TRD or HC (F = 11.030, p < 0.001; F = 10.309, p < 0.001, respectively). After an adequate trial of escitalopram treatment, the LICI of non-TRD reduced significantly (t = - 3.628, p < 0.001), whereas the ICF remained lower than that of HC and showed no difference from pretreatment non-TRD.

CONCLUSIONS

TRD was characterized by relatively reduced CI, including both GABAA- and GABAB-receptor-mediated neurons while non-TRD preserved partial CI. In non-TRD, SSRIs may mainly modulate GABAB-receptor-related LICI. Our findings revealed distinguishable features of CI in antidepressant-resistant and responsive major depression.

Mood, Dimensional Personality, and Suicidality in a Longitudinal Sample of Patients with Bipolar Disorder and Controls

OBJECTIVE

To evaluate the effects of mood and anxiety symptoms in relation to personality dimensions and clinical features such as trauma and substance use on suicidal behaviors in a longitudinal sample of individuals with bipolar illness (BP) and healthy controls (HC).

METHODS

Mood, personality, and clinical features were assessed in 151 individuals with BP I and 119 HC. Clinical data were collected at baseline and at 2-year follow-up. Personality traits were measured using the NEO PI-R.

RESULTS

In bivariate analyses, personality measures were significantly different between BP and HC, and between BP based on suicide attempt history. However, in regression analyses, baseline measures of depression, mania, anxiety, trauma, education, and age of BP onset correlated with personality domains, while a history of suicide attempts did not. Logistic regressions showed that prospective depression or mania, and a pattern of mixed mood features and chronicity of illness, along with two Neuroticism facet scores (N4-Self-Consciousness and N6-Vulnerability) were predictive of suicide ideation (SI) in the 2-year follow-up period.

CONCLUSIONS

While dimensions of personality, trauma, and substance use clearly correlated with suicidal behaviors in BP, in multivariate models emerging mood symptoms were the most robust predictors of suicidality. These results reinforce the importance and attributable role of mood and anxiety symptoms in evaluating suicidal risk.

Prevalence, clinical correlates and IQ of suicidal ideation in drug naïve Chinese Han patients with major depressive disorder

BACKGROUND

Suicidal ideation (SI) is a common and serious clinical concern in people with major depressive disorder (MDD). Inconsistent evidence suggests that individuals with SI may have a lower measured intelligence quotient (IQ) than those without SI. The aims of this study were to examine SI prevalence and its associations with demographic, clinical variables and IQ in Chinese drug-naïve MDD patients.

METHODS

488 drug-naïve Chinese Han patients (male: 203, 41.6%) meeting a DSM-IV diagnosis of MDD were enrolled in a cross-sectional study involving seven hospitals. All participants were asked to complete a series of questionnaires, which include information on socio-demographic and clinical variables. The Hamilton Depression Rating Scale (HAMD), Hamilton Anxiety Rating Scale (HAMA) and Brief Psychiatric Rating Scale (BPRS) were also administered. Verbal IQ (VIQ), performance IQ (PIQ) and full-scale IQ (FIQ) scores were measured using the Chinese version of the Wechsler Adult Intelligence Scale-Ⅲ (WAIS-Ⅲ). We categorized patients with SI based on a cut-off score of ≥3 on HAMD item 3.

RESULTS

An estimated prevalence 32.8% (160/488) of drug-naïve MDD patients experienced SI during the current episode of illness. Patients with SI were more likely to be divorced (x²= 6.93, p = 0.031), male (x²= 6.04, p = 0.014), had higher severity of depression and anxiety symptoms (t = -8.14, p < 0.001, t = -3.28, p < 0.001, respectively), comorbid psychotic features (t = -5.71, p < 0.001), and lower FIQ levels (t = -4.21, p < 0.001), when compared to patients without SI. Using logistic regression analysis and adjusting for confounding variables, the following variables were independently associated with SI: divorced marital status compared to married (OR=4.674, 95% CI: 1.676~13.036), severity of depression symptoms (OR=1.312, 95% CI: 1.196~1.440), psychotic features (OR=1.044; 1.012~1.077), and FIQ /PIQ levels which expressed in OR per SD increase in IQ score (OR=0.740, 95% CI: 0.561~0.977; OR=0.744, 95% CI: 0.557~0.994, respectively).

LIMITATIONS

A cross-sectional study which did not assess the influence of severity of SI.

CONCLUSIONS

The prevalence of SI in drug-naive Chinese patients with MDD is high, and associated with marital status, severity of depression, psychotic features and measured IQ. Further research is needed to further explore these and other potentially relevant risk factors which might affect clinical outcomes.

Association between personality traits and risk of suicidal ideation in Chinese university students: Analysis of the correlation among five personalities

The purpose of our study was to determine the incidence of suicidal ideation among Chinese college students and to explore the risk factors for suicidal ideation. A large-sample epidemiological survey was conducted in 13 colleges in Chongqing, China (n = 69,790). Suicidal ideation was reported by 13.03% of the college students who were surveyed. The participants with suicidal ideation were more likely to be female, to come from rural areas, and to have poor life quality and psychological disorder compared to those without suicidal ideation. Moreover, this study revealed that neuroticism, psychoticism, impulsivity, and aggression are risk factors for suicidal ideation, while extroversion has a protective effect on suicidal ideation. We found that four personality traits of students with suicidal ideation, including impulsivity, aggression, psychoticism, and neuroticism, are positively correlated. However, there is a negative correlation between extroversion and the other four traits. These findings highlight the need for further exploration of personality traits in the risk of suicidal ideation.

The role of neuroticism in self-harm and suicidal ideation: results from two UK population-based cohorts

BACKGROUND

Self-harm is common, debilitating and associated with completed suicide and increased all-cause mortality, but there is uncertainty about its causal risk factors, limiting risk assessment and effective management. Neuroticism is a stable personality trait associated with self-harm and suicidal ideation, and correlated with coping styles, but its value as an independent predictor of these outcomes is disputed.

METHODS

Prior history of hospital-treated self-harm was obtained by record-linkage to administrative health data in Generation Scotland:Scottish Family Health Study (N = 15,798; self-harm cases = 339) and by a self-report variable in UK Biobank (N = 35,227; self-harm cases = 772). Neuroticism in both cohorts was measured using the Eysenck Personality Questionnaire-Short Form. Associations of neuroticism with self-harm were tested using multivariable regression following adjustment for age, sex, cognitive ability, educational attainment, socioeconomic deprivation, and relationship status. A subset of GS:SFHS was followed-up with suicidal ideation elicited by self-report (n = 3342, suicidal ideation cases = 158) and coping styles measured by the Coping Inventory for Stressful Situations. The relationship of neuroticism to suicidal ideation, and the role of coping style, was then investigated using multivariable logistic regression.

RESULTS

Neuroticism was positively associated with hospital-associated self-harm in GS:SFHS (per EPQ-SF unit odds ratio 1.2 95% credible interval 1.1-1.2, p_FDR 0.0003) and UKB (per EPQ-SF unit odds ratio 1.1 95% confidence interval 1.1-1.2, p_FDR 9.8 × 10^-17). Neuroticism, and the neuroticism-correlated coping style, emotion-oriented coping (EoC), were also associated with suicidal ideation in multivariable models.

CONCLUSIONS

Neuroticism is an independent predictor of hospital-treated self-harm risk. Neuroticism and emotion-orientated coping styles are also predictive of suicidal ideation.

MicroRNAs in depression and suicide: Recent insights and future perspectives

Suicide is a major public health concern. A significant proportion of depressed individuals show suicidal ideation. The currently available medications are not optimal and a large number of depressed/suicidal patients do not respond to these medications. Thus, there is an urgent need to fully understand the neurobiological mechanisms associated with depression and suicidal behavior and to find novel targets for therapeutic interventions. In this regard, microRNAs (miRNAs), member of small non-coding RNA family, have emerged as an invaluable tool not only to understand disease pathogenesis but also to precisely pinpoint the targets that can be developed as drugs. In this review, these aspects have been discussed in a comprehensive and critical manner.

Clarifying the role of neuroticism in suicidal ideation and suicide attempt among women with major depressive disorder

BACKGROUND

Prior research consistently demonstrates that neuroticism increases risk for suicidal ideation, but the association between neuroticism and suicidal behavior has been inconsistent. Whereas neuroticism is recommended as an endophenotype for suicidality, the association of neuroticism with attempted suicide warrants clarification. In particular, prior research has not distinguished between correlates of attempted suicide, correlates of suicidal ideation, and correlates of comorbid psychopathology.

METHODS

The present study used the CONVERGE study, a sample of 5864 women with major depressive disorder (MD) and 5783 women without MD throughout China. Diagnoses, suicidal ideation, and attempted suicide were assessed with the Composite International Diagnostic Interview (CIDI). Neuroticism was assessed with the neuroticism portion of the Eysenck Personality Questionnaire.

RESULTS

Results replicate prior findings on the correlates of suicidal ideation, particularly elevated neuroticism among individuals who report prior suicidal ideation. Moreover, as compared with individuals who reported having experienced only suicidal ideation, neuroticism was associated with decreased likelihood of having attempted suicide.

CONCLUSIONS

The association of neuroticism with suicidality is more complicated than has been previously described. Whereas neuroticism increases risk for suicidal ideation, neuroticism may decrease risk for a suicide attempt among individuals with suicidal ideation. These results have implications for the assessment of risk for a suicide attempt among individuals who report suicidal ideation and addresses prior discordant findings by clarifying the association between neuroticism and attempted suicide.

Association between cognitive deficits and suicidal ideation in patients with major depressive disorder

The role of cognitive function in suicidal ideation in patients with major depressive disorder (MDD) has not been adequately explored. This research sought to measure the relationship between suicidal ideation and cognitive function. Therefore, in this study, the association between cognitive function and suicidal ideation in patients with MDD was assessed. Cognitive function was evaluated in 233 patients with MDD using the Japanese version of the Brief Assessment of Cognition in Schizophrenia (BACS). Suicidal ideation was assessed using item 3 of the Hamilton Depression Rating Scale. Approximately 59.2% of the patients (138/233) expressed suicidal ideation. Among the BACS subtests, only the executive function scores were significantly lower in patients with MDD with than in those without (p < 0.005). In addition, the executive function, motor speed function, and composite scores correlated negatively with the severity of suicidal ideation in these patients. These results suggest that executive function, motor speed function, and global neuropsychological function are associated with suicidal ideation in patients with MDD and that the BACS neuropsychological battery is an efficient instrument for monitoring these characteristics. Moreover, specific BACS scores can potentially serve as cognitive biomarkers of suicide risk in patients with MDD.

Role of depression severity and impulsivity in the relationship between hopelessness and suicidal ideation in patients with major depressive disorder

BACKGROUND

Hopelessness, depression and impulsivity all contribute to the development of suicidal ideation in patients with major depressive disorder, but the pathway of these factors to suicidal ideation is not clear. This study examined the meditating effect of depression severity on the relationship between hopelessness and suicidal ideation and explored how this mediating effect was moderated by impulsivity.

METHODS

A total of 162 patients with major depressive disorder (MDD) completed a structured clinical diagnostic interview and a battery of scales assessing depression severity, hopelessness, suicidal ideation, and impulsivity. Regression analyses with bootstrapping methods were used to examine the mediating and moderating effects of various risk factors.

RESULTS

Mediation analysis revealed a significant indirect effect of hopelessness on suicidal ideation, and the effect was fully mediated through depression severity. On moderation analysis, the moderating effects of the relationship between depression severity and suicidal ideation were significant in both the medium and high impulsivity groups.

LIMITATIONS

The present study was limited by the assessment of trait impulsivity and observer-rated depression severity, which might not fully reflect momentary impulsivity and feeling of depression when suicidal ideation occurs.

CONCLUSION

Depression severity plays a mediator role in the relationship between hopelessness and suicidal ideation and this mechanism is contingent on the levels of impulsivity. MDD patients with higher impulsivity appear to be more likely to have suicidal ideations even when they are less depressed. These findings highlight the importance of impulsivity assessment and alleviation of depressive symptoms to prevent suicidality in patients with MDD.

Personality traits in children of parents with unipolar and bipolar mood disorders

BACKGROUND

Using family study data, the following questions regarding the mechanisms of association between personality traits and mood disorders were addressed: 1) Is there an association between unipolar and bipolar mood disorders and personality traits in probands? 2) Are personality traits associated with depression in their 9 to 17 year-old children? 3) Is there an association between parental mood disorders and personality traits in offspring? 4) Are parental personality traits associated with the risk of depression in offspring?

METHODS

The study included 50 probands with bipolar and 37 with unipolar mood disorder, 34 healthy controls as well as 178 of their children between 9 and 17 years. Diagnoses were made according to a best-estimate procedure based on a semi-structured interview (DIGS), medical records and family history information. Personality traits were assessed using the Eysenck Personality Questionnaire in adults and the Eysenck Personality Questionnaire Junior in offspring.

RESULTS

Personality traits, and in particular Neuroticism, were found to be associated with mood disorders in currently affected as well as remitted probands and offspring. However, there was no association between mood disorders in parents and personality traits in their children, and conversely, parental personality traits were not associated with the risk of depression in offspring.

LIMITATIONS

1) Relatively small proportion of offspring who were still unaffected but likely to subsequently develop mood disorders; 2) cross-sectional design.

CONCLUSIONS

The findings were best compatible with the complication or scar hypothesis, which assumes the occurrence of abnormal personality traits as a consequence of previous depressive episodes.

Temperament and character of suicide attempters

Temperamental features are strongly associated with suicidal behaviors both in general population and clinical samples. In the present study we considered the association between personality traits, measured by Temperament and Character Inventory (TCI), and suicidal behavior. We analyzed five samples: a German control sample of 1148 healthy individuals; 144 German suicide attempters affected by Mood (n=101), Schizophrenia spectrum (n=20) and Borderline Personality (n=23) Disorders; 46 Italian suicide attempters affected by Mood Disorders (UP=15; BP=31); 76 German non-suicide Mood Disorder patients; 147 Italian non-suicide Mood Disorder patients. Suicide attempters showed higher scores in Harm Avoidance (HA) and lower scores in Self-Directedness (SD) and Cooperativeness (C), when compared to controls. Nevertheless, comparing the German and the Italian suicide attempter groups with the non-suicide Mood Disorder patient groups, no differences were detected. This could be due to the effect of Mood Disorder on personality. In conclusion, the present study reveals the difficulty to disentangle the personality profile of suicide attempters from their psychopathology. Those findings may be useful for cautions in further dissecting this complex phenotype.

Interrelationship of childhood trauma, neuroticism, and depressive phenotype

Both childhood trauma (CT) and genetic factors contribute to the pathophysiology of depression. We studied the relationship of CT to age of onset (AO) of depression, personality traits, and expression of symptom dimensions in 324 adults with recurrent unipolar depression. Subjects received structured psychiatric interviews and completed CT, depressive symptom, and personality rating questionnaires. Experience of at least one type of trauma was reported by 79.9% of subjects, and the most common forms of trauma were physical neglect, emotional abuse, and emotional neglect. There was an earlier AO of depression in the groups that reported CT compared to those that reported none, with earliest AO occurring in those who had experienced the highest levels of CT. There were no significant correlations between overall CT scores and neuroticism or extraversion. Total CT was a significant (P=.008) predictor of the Mood symptom dimension, mostly accounted for by emotional abuse (P=.019), and physical neglect predicted the Anxiety symptom dimension (P=.002). All types of CT are commonly reported in individuals with depression, and emotional abuse and physical neglect, though previously less well identified, appear to have an important role in the pathogenesis of depressive disorders. The effect of CT on individuals with an underlying genetic vulnerability to depression may result in differences in depressive phenotype characterized by earlier AO of depression and the expression of specific depressive symptom dimensions.

Personality traits as correlates of suicidal ideation, suicide attempts, and suicide completions: a systematic review

OBJECTIVE

Involvement of personality traits in susceptibility to suicidality has been the subject of research since the 1950s. Because of the diversity of conceptual and methodological approaches, the extent of their independent contribution has been difficult to establish. Here, we review conceptual background and empirical evidence investigating roles of traits in suicidal behaviors.

METHOD

We selected original studies published in English in MEDLINE and PsycINFO databases, focusing on suicidal ideation, suicide attempts, or suicide completions, and using standardized personality measures.

RESULTS

Most studies focused on investigating risk for suicide attempts. Hopelessness, neuroticism, and extroversion hold the most promise in relation to risk screening across all three suicidal behaviors. More research is needed regarding aggression, impulsivity, anger, irritability, hostility, and anxiety.

CONCLUSION

Selected personality traits may be useful markers of suicide risk. Future research needs to establish their contributions in relation to environmental and genetic variation in different gender, age, and ethnocultural groups.

Do antidepressants reduce the burden imposed by depression on employers?

The ability to perform paid or unpaid work is integral to an individual's quality of life. Therefore, we performed a systematic literature review to examine the impact of depression and its treatment on occupational outcomes. This review found absenteeism from work to be markedly higher among depressed employees and productivity to be dramatically undermined by some symptoms of depression. Gaps in the published literature point to the need for future economic and clinical analyses to include work-related outcomes. Published studies showed that antidepressants can enhance work-related outcomes by alleviating affective symptoms. However, the pharmacological properties of antidepressants may produce differential effects that influence work-related outcomes in other ways. For example, TCAs, but not SSRIs, produce sedation and impair cognitive function in ways that could undermine work-related outcomes. Formal analyses are required to quantify whether the improved social functioning, motivation and vigilance that may be associated with some newer antidepressants translate into improved work-related outcomes. Although few published studies have directly quantified the cost benefit of managing depression and associated lost productivity, existing studies that directly assessed work-related outcomes have suggested that treating depression is cost effective. Gaps in the published literature imply that the impact of depression and antidepressants on occupational outcomes has been understudied. This reflects, in part, the fact that antidepressant studies lasting 4 or 6 weeks are unlikely to capture the impact of treatment on work-related measures. In addition, the current evidence base is fraught with other methodological limitations. The effect of depression on non-paid employment also requires further assessment. In conclusion, the efficacy of antidepressants on work-related outcomes should be measured in clinical trials that have an adequate design and a suitable follow-up period, and included in health technology assessments. Until such studies are available, the evidence base supporting the use of antidepressants will remain incomplete.

The neurobiology of suicide and suicidality

OBJECTIVE

To investigate the current state of knowledge regarding the neurobiology of suicide and suicidality.

METHOD

The literature on the neurobiology of suicidality and suicide was reviewed.

RESULTS

There is clear evidence that the activity of 3 neurobiological systems has a role in the pathophysiology of suicidal behaviour. This includes hyperactivity of the hypothalamo-pituitary-adrenal axis, dysfunction of the serotonergic (5-HTergic) system, and excessive activity of the noradrenergic system. While the first and the last system appear to be involved in the response to stressful events, dysfunction of the serotonergic system is thought to be trait-dependent and associated with disturbances in the regulation of anxiety, impulsivity, and aggression. It can be hypothesized that neurobiological dysfunctions mediate the occurrence of suicidal behaviour through the disturbed modulation of basic neuropsychological functions.

CONCLUSION

Increasing insight into the neurobiological basis of suicidal behaviour suggests that serotonin (5-HT) agonists have an important role in the treatment and prevention of suicidal behaviour. Studies of the efficacy of such drugs have, however, been disappointing. Because suicidal behaviour continues to be a major public health problem, further study is clearly needed, including research on the effect of combined pharmacologic and psychotherapeutic approaches.