Prefrontal 5-HT2a receptor binding index, hopelessness and personality characteristics in attempted suicide

Regional brain glucose uptake distinguishes suicide attempters from non-attempters in major depression

This study compared regional cerebral metabolic rates of glucose (rCMRglu) determined by [(18)F]-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) in suicide attempters and non-attempters. Medication-free patients with major depression (n = 29) had FDG-PET after single-blind administration of placebo (day 1) and fenfluramine (day 2). Suicide attempt history was obtained before scanning and at assessments over 2 subsequent years. Statistical parametric mapping evaluated associations between attempt status and rCMRglu, controlling for age. The study included 13 patients with and 16 without a history of suicide attempt within 2 years before or after scanning. After placebo, rCMRglu in attempters was lower in right dorsolateral prefrontal regions and higher in ventromedial regions than in non-attempters. After fenfluramine, relatively hypometabolic areas enlarged, and no hypermetabolic areas were detected. Distinct rCMRglu patterns may be serotonin-sensitive biomarkers of suicide risk.

Current suicidality and previous suicidal attempts in patients with schizophrenia are associated with different dimensions of temperament and character

Suicide is a major public health problem and the leading cause of premature death in patients with schizophrenia. Information about the patient's personality is helpful for assessing the risk of suicide attempts and suicidal ideation. The sample consisted of 120 outpatients with a diagnosis of schizophrenia, 29 of whom had previously attempted suicide. We used the Temperament and Character Inventory to assess personality differences between patients who had previously attempted and had not previously attempted suicide and between patients who had and did not have current suicidal ideation. Current suicidal ideation was assessed using the four-point severity scale, which is item nine from the Beck Depression Inventory. The character dimension Self-transcendence was shown by logistic regression to be a predictor of lifetime suicide attempts. Low Self-directedness was shown to be a predictor of current suicidal ideation. To prevent suicidal behaviour, it is important to better understand the personality traits associated with suicidal ideation and suicide attempts. Suicide attempts and suicidal ideation in schizophrenia may not represent the same phenomenon ranging on a single continuum. The importance of these results suggests that further study is needed.

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.

Current status of functional imaging in eating disorders

Eating Disorders are complex psychiatric problems that involve biologic and psychological factors. Brain imaging studies provide insights about how functionally connected brain networks may contribute to disturbed eating behavior, resulting in food refusal and altered body weight, but also body preoccupations and heightened anxiety. In this article, we review the current state of brain imaging in eating disorders, and how such techniques may help identify pathways that could be important in the treatment of those often detrimental disorders.

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.

Key players in major and bipolar depression--a retrospective analysis of in vivo imaging studies

In the present study, we evaluated the contribution of the individual synaptic constituents of all assessed neurotransmitter systems by subjecting all available in vivo imaging studies on patients with unipolar major depressive disorder (MDD) and bipolar depression (BD) to a retrospective analysis. In acute MDD, findings revealed significant increases of prefrontal and frontal DA synthesis, decreases of thalamic and midbrain SERT, increases of insular SERT, decreases of midbrain 5-HT(1A) receptors and decreases of prefrontal, frontal, occipital and cingulate 5-HT(2A) receptors, whereas, in remission, decreases of striatal D₂ receptors, midbrain SERT, frontal, parietal, temporal, occipital and cingulate 5-HT(1A) receptors and parietal 5-HT(2A) receptors were observed. In BD, findings indicated a trend towards increased striatal D₂ receptors in depression and mania, decreased striatal DA synthesis in remission and decreased frontal D₁ receptors in all three conditions. Additionally, there is some evidence that ventrostriatal and hippocampal SERT may be decreased in depression, whereas in remission and mania elevations of thalamic and midbrain SERT, respectively, were observed. Moreover, in depression, limbic 5-HT(1A) receptors were elevated, whereas in mania a decrease of both cortical and limbic 5-HT(2A) receptor binding was observed. Furthermore, in depression, prefrontal, frontal, occipital and cingulate M2 receptor binding was found to be reduced. From this, a complex pattern of dysregulations within and between neurotransmitter systems may be derived, which is likely to be causally linked not only with the subtype and duration of disease but also with the predominance of individual symptoms and with the kind and duration of pharmacological treatment(s).

Hopelessness, a potential endophenotpye for suicidal behavior, is influenced by TPH2 gene variants

OBJECTIVES

Hopelessness is one of the strongest risk factors for suicidal behavior but relevant genetic studies are poorly available. Tryptophan hydroxylase (TPH) is widely considered to be a good candidate for genetic association studies on depression and suicide, however, investigations on these complex, multifactorial phenotypes have resulted in conflicting data. We hypothesized that hopelessness could be a mediating phenotype between TPH2 gene, depression and suicidal behavior.

METHODS

Depressive phenotype and suicidal risk were investigated of 760 individuals from general population by Zung Self Rating Depression Scale (ZDS), Beck's Hopelessness Scale (BHS) and a detailed background questionnaire. All participants' DNA samples were genotyped for 7 tag SNPs in TPH2 gene. Generalized linear models were performed for single marker association studies and p-values were corrected by Bonferroni criteria. In haplotype analyses score tests were used and permutated p-values were computed.

RESULTS

Four SNPs of TPH2 gene showed association with hopelessness but only rs6582078 had a significant effect on the BHS scores after Bonferroni's correction; GG individuals had significantly higher BHS scores, while GT and TT had intermediate and lower BHS scores respectively (p=0.0047). Compared with other genotypes, homozygous GG individuals also had almost three times greater estimated suicidal risk, as did carriers of the AA genotype of rs6582078 (OR=2.87; p=0.005) and also of rs1352250 (OR=2.86; p=0.006). A risk and a protective haplotype of TPH2 gene were also identified in association with hopelessness. ZDS scores have not shown any association with TPH2 gene.

CONCLUSIONS

We found that hopelessness, with its allied increased suicidal risk was strongly associated with TPH2 gene variants in multiple tests. These findings suggest that TPH2 gene confers risk for suicidal behavior while hopelessness can be a potential endophenotype for suicidal vulnerability.

Is treatment-resistance in unipolar melancholic depression characterized by decreased serotonin₂A receptors in the dorsal prefrontal - anterior cingulate cortex?

OBJECTIVES

Quite a number of patients diagnosed with major depression are resistant to several well carried-out psychopharmacological interventions. It remains unclear as to how the serotonergic system is implicated in the phenomenon of treatment-resistance.

METHODS

We examined the involvement of post-synaptic 5-HT(2A) receptors in the pathophysiology of treatment-resistance in unipolar melancholic major depression with (123)I-5-I-R91150 SPECT. 15 antidepressant-naïve (ADN) first-episode depressed patients, 15 antidepressant-free treatment-resistant depressed (TRD) patients and 15 never-depressed individuals, matched for age and gender were studied.

RESULTS

Compared to ADN patients and healthy controls, TRD patients displayed significantly lower 5-HT(2A) receptor binding index (BI) in the dorsal regions of the prefrontal and the anterior cingulate cortex. No significant 5-HT(2A) receptor BI differences between ADN patients and controls were observed.

CONCLUSIONS

At the cortical level, 5-HT(2A) receptor BI does not significantly differ in first-episode melancholic depressed patients compared to healthy controls. This observation might imply a limited short-term impact on the serotonergic system in first episode depression. Our results also suggest that when encountered with treatment-resistance, the 5-HT(2A) receptors in the DPFC-ACC axis are significantly down-regulated. However, whether this assumed underlying pathophysiological mechanism is due solely to abnormalities in the serotonergic system remains to be answered. This article is part of a Special Issue entitled 'Anxiety and Depression'.

The suicidal mind and brain: a review of neuropsychological and neuroimaging studies

OBJECTIVES. We aimed at reviewing studies exploring dysfunctional cognitive processes, and their neuroanatomical basis, in suicidal behaviour, and to develop a neurocognitive working model. Methods. A literature search was conducted. RESULTS. Several limitations were found. The main reported neuropsychological findings are a higher attention to specific negative emotional stimuli, impaired decision-making, lower problem-solving abilities, reduced verbal fluency, and possible reduced non-specific attention and reversal learning in suicide attempters. Neuroimaging studies mainly showed the involvement of ventrolateral orbital, dorsomedial and dorsolateral prefrontal cortices, the anterior cingulate gyrus, and, to a lesser extent, the amygdala. In addition, alterations in white matter connections are suggested. CONCLUSIONS. These studies support the concept of alterations in suicidal behaviour distinct from those of comorbid disorders. We propose that a series of neurocognitive dysfunctions, some with trait-like characteristics, may facilitate the development of a suicidal crisis during stressful circumstances: (1) an altered modulation of value attribution, (2) an inadequate regulation of emotional and cognitive responses, and (3) a facilitation of acts in an emotional context. This preliminary model may represent a framework for the design of future studies on the pathophysiology, prediction and prevention of these complex human behaviours.

Decreased cerebral blood flow in the limbic and prefrontal cortex using SPECT imaging in a cohort of completed suicides

Suicide has a high comorbidity with impulsivity and depression, and finding imaging biomarkers indicative of patients at high risk for suicidal behavior is invaluable to the clinician. Using single-photon emission computed tomography (SPECT) imaging, we have previously reported regional cerebral blood flow (rCBF) decreases in the medial prefrontal cortex, ventral tegmental area and subgenual cingulate cortex (Brodmann area 25 (BA 25)), a region found to be hypoperfused with treatment-resistant depression. From 2007 to 2010, we have extended our analysis to include nine additional completed suicides. In all, 27 healthy, age- and gender-matched subjects from a previously acquired healthy brain study served as controls to our 21 completed suicides. All 21 suicides had been previously diagnosed with depression according to Diagnostic and Statistical Manual of Mental Disorder-IV criterion. Voxel-by-voxel analyses were performed using statistical parametric mapping to compare the differences in technetium-99m hexamethylpropylene amine oxime brain uptake between the groups. Factor analysis of the data identified the top 10 regions of hypoperfusion in the suicidal group, including the bilateral superior frontal lobes, the right precuneus, the rolandic operculum, postcentral gyrus, left caudate and insular cortex. We also demonstrate more focal decreases in rCBF in the subgenual cingulate cortex (BA 25) in 18 subjects, supporting our previous hypothesis that hypoperfusion of BA 25 may be a risk factor for suicide in depressed patients. This work suggests that SPECT might be useful in predicting risk for suicide completion in subjects with depression or treatment-resistant depression. Further investigation of this work is necessary to better understand the predictive value of this finding.

5-HT radioligands for human brain imaging with PET and SPECT

The serotonergic system plays a key modulatory role in the brain and is the target for many drug treatments for brain disorders either through reuptake blockade or via interactions at the 14 subtypes of 5-HT receptors. This review provides the history and current status of radioligands used for positron emission tomography (PET) and single photon emission computerized tomography (SPECT) imaging of human brain serotonin (5-HT) receptors, the 5-HT transporter (SERT), and 5-HT synthesis rate. Currently available radioligands for in vivo brain imaging of the 5-HT system in humans include antagonists for the 5-HT(1A), 5-HT(1B), 5-HT(2A), and 5-HT(4) receptors, and for SERT. Here we describe the evolution of these radioligands, along with the attempts made to develop radioligands for additional serotonergic targets. We describe the properties needed for a radioligand to become successful and the main caveats. The success of a PET or SPECT radioligand can ultimately be assessed by its frequency of use, its utility in humans, and the number of research sites using it relative to its invention date, and so these aspects are also covered. In conclusion, the development of PET and SPECT radioligands to image serotonergic targets is of high interest, and successful evaluation in humans is leading to invaluable insight into normal and abnormal brain function, emphasizing the need for continued development of both SPECT and PET radioligands for human brain imaging.

Structural and functional neuroimaging studies of the suicidal brain

Suicidality is a major challenge for today's health care. Evidence suggests that there are differences in cognitive functioning of suicidal patients but the knowledge about the underlying neurobiology is limited. Brain imaging offers the advantage of a non-invasive in vivo direct estimation of detailed brain structure, regional brain functioning and estimation of molecular processes in the brain. We have reviewed the literature on neuroimaging studies of the suicidal brain. This article contains studies on structural imaging such as Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) and functional imaging, consisting of Positron Emission Tomography (PET), Single Photon Emission Tomography (SPECT) and functional MRI (fMRI). We classified the results of the different imaging modalities in structural and functional imaging. Within our research, we found no significant differences in the suicidal brain demonstrated by Computed Tomography. Magnetic Resonance Imaging studies in subjects with a history of suicide attempt on the other hand deliver differing results, mostly pointing at a higher prevalence of white (especially deep white matter and periventricular) and grey matter hyperintensities in the frontal, temporal and/or parietal lobe and decreased volumes in the frontal and temporal lobe. There seems to be a trend towards findings of reduced grey matter volume in the frontal lobe. Overall, there is no consensus of opinion on structural imaging of the suicidal brain. Research on functional imaging is further divided into studies in resting state, studies in activation conditions and studies on brain neurotransmitters, transporters and receptors. A common finding in functional neuroimaging in resting conditions is a decreased perfusion in the prefrontal cortex of suicidal patients. During cognitive activation, perfusion deficits in the prefrontal cortex have been observed. After fenfluramine challenge, the prefrontal cortex metabolism seems to be inversely correlated to the lethality of previous suicide attempt. The few studies that examined the serotonin transporter in suicide found no significant differences in binding potential. In suicide attempters there seems to be a negative correlation between impulsivity and SERT binding. Our group found a reduced 5-HT(2A) binding in the frontal cortex in patients with a recent suicide attempt. The binding index was significantly lower in the deliberate self injury patients compared to the deliberate self poisoning patients. The few authors that examined DAT binding in suicide found no significant DAT differences between patients and controls. However they demonstrated significant negative correlations between DAT binding potential and mental energy among suicide attempters, but not in healthy control subjects. We did not find studies measuring the binding potential of the noradrenalin or gamma amino butyric acid transporter or receptor in suicidal subjects. Several reports have suggested abnormalities of GABA neurotransmission in depression. During our literature search, we have focused on neuroimaging studies in suicidal populations, but in the absence of evidence in the literature on this group or when further collateral evidence is appropriate, this overview expands to results in impulsive aggressive or in depressed subjects.

The neuroscience of suicidal behaviors: what can we expect from endophenotype strategies?

Vulnerability to suicidal behavior (SB) is likely mediated by an underlying genetic predisposition interacting with environmental and probable epigenetic factors throughout the lifespan to modify the function of neuronal circuits, thus rendering an individual more likely to engage in a suicidal act. Improving our understanding of the neuroscience underlying SBs, both attempts and completions, at all developmental stages is crucial for more effective preventive treatments and for better identification of vulnerable individuals. Recent studies have characterized SB using an endophenotype strategy, which aims to identify quantitative measures that reflect genetically influenced stable changes in brain function. In addition to aiding in the functional characterization of susceptibility genes, endophenotypic research strategies may have a wider impact in determining vulnerability to SB, as well as the translation of human findings to animal models, and vice versa. Endophenotypes associated with vulnerability to SB include impulsive/aggressive personality traits and disadvantageous decision making. Deficits in realistic risk evaluation represent key processes in vulnerability to SB. Serotonin dysfunction, indicated by neuroendocrine responses and neuroimaging, is also strongly implicated as a potential endophenotype and is linked with impulsive aggression and disadvantageous decision making. Specific endophenotypes may represent heritable markers for the identification of vulnerable patients and may be relevant targets for successful suicide prevention and treatments.

Measuring serotonin synthesis: from conventional methods to PET tracers and their (pre)clinical implications

The serotonergic system of the brain is complex, with an extensive innervation pattern covering all brain regions and endowed with at least 15 different receptors (each with their particular distribution patterns), specific reuptake mechanisms and synthetic processes. Many aspects of the functioning of the serotonergic system are still unclear, partially because of the difficulty of measuring physiological processes in the living brain. In this review we give an overview of the conventional methods of measuring serotonin synthesis and methods using positron emission tomography (PET) tracers, more specifically with respect to serotonergic function in affective disorders. Conventional methods are invasive and do not directly measure synthesis rates. Although they may give insight into turnover rates, a more direct measurement may be preferred. PET is a noninvasive technique which can trace metabolic processes, like serotonin synthesis. Tracers developed for this purpose are α-[¹¹C]methyltryptophan ([¹¹C]AMT) and 5-hydroxy-L-[β-¹¹C]tryptophan ([¹¹C]5-HTP). Both tracers have advantages and disadvantages. [¹¹C]AMT can enter the kynurenine pathway under inflammatory conditions (and thus provide a false signal), but this tracer has been used in many studies leading to novel insights regarding antidepressant action. [¹¹C]5-HTP is difficult to produce, but trapping of this compound may better represent serotonin synthesis. AMT and 5-HTP kinetics are differently affected by tryptophan depletion and changes of mood. This may indicate that both tracers are associated with different enzymatic processes. In conclusion, PET with radiolabelled substrates for the serotonergic pathway is the only direct way to detect changes of serotonin synthesis in the living brain.

Suicidal brains: a review of functional and structural brain studies in association with suicidal behaviour

Evidence of an association between a vulnerability to suicidal behaviour and neurobiological abnormalities is accumulating. Post-mortem studies have demonstrated structural and biochemical changes in the brains of suicide victims. More recently, imaging techniques have become available to study changes in the brain in vivo. This systematic review of comparative imaging studies of suicidal brains shows that changes in the structure and functions of the brain in association with suicidal behaviour are mainly found in the orbitofrontal and dorsolateral parts of the prefrontal cortex. Correlational studies suggest that these changes relate to neuropsychological disturbances in decision-making, problem solving and fluency, respectively. As a consequence, the findings from these studies suggest that suicidal behaviour is associated with (1) a particular sensitivity to social disapproval (2) choosing options with high immediate reward and (3) a reduced ability to generate positive future events. Further study is needed to elaborate these findings and to investigate to what extent changes in the structure and function of suicidal brains are amenable to psychological and/or biological interventions.

Cholesterol and CSF 5-HIAA in attempted suicide

BACKGROUND

Low serum cholesterol has been linked to suicide and violent behaviour. The same kind of associations has been reported regarding low levels of 5-hydroxyindolacetic acid (5-HIAA) in the cerebrospinal fluid (CSF) and suicidal behaviour. The hypothesis of the link between serum cholesterol and suicide incorporate serotonin. It proposes that low cholesterol is related to altered serotonergic neurotransmission. A correlation between CSF 5-HIAA and serum cholesterol has been shown in animal studies, but has not been found in humans.

AIM

To study the interrelationship between serum cholesterol and CSF 5-HIAA in suicide attempters. Since both cholesterol and CSF 5-HIAA are associated with suicide and violent suicide attempts, we also investigated the correlation with suicide, violent suicide attempt method, suicide intent, hopelessness and depression severity.

METHODS

Serum total cholesterol and CSF 5-HIAA were measured in 42 medication free suicide attempters. Patients were assessed with Becks's Hopelessness scale (BHS), Suicide Intent Scale (SIS) and Montgomery-Asberg depression rating scale (MADRS) and followed-up for causes of death.

RESULTS

Serum total cholesterol and CSF 5-HIAA showed a significant positive correlation adjusted for age, body mass index and substance abuse diagnosis. Cholesterol and CSF 5-HIAA levels did not differ between violent and non-violent suicide attempters or between suicide completers and survivors.

CONCLUSIONS

These findings indicate that the serotonergic system may be connected to serum cholesterol in patients with a recent suicide attempt.

Gender, personality, and serotonin-2A receptor binding in healthy subjects

The vulnerability to mood disorders, impulsive-aggression, eating disorders, and suicidal behavior varies greatly with gender, and may reflect gender differences in central serotonergic function. We investigated the relationships of gender, mood, impulsivity, aggression and temperament to 5HT(2A) receptor binding in 21 healthy subjects using [18F]altanserin and PET neuroimaging. Binding potentials in pre-defined regions-of-interest (ROI) were calculated using the Logan graphical method, corrected for partial volume effects, and compared by gender with age co-varied. SPM analysis was used for voxel level comparisons. Altanserin binding (BP(P)) was greater in male than female subjects in the following nine ROIs: hippocampus (HIP) and Lt. HIP, lateral orbital frontal cortex (LOF) and Lt. LOF, left medial frontal cortex (Lt. MFC), left medial temporal cortex (Lt. MTC), left occipital cortex (Lt. OCC), thalamus (THL) and Lt. THL. Differences in Lt. HIP and Lt. MTL remained significant after Bonferroni correction. Gender differences were noted in the co-variation of psychological traits with BP(P) values in specific ROIs. Among males alone, aggression was negatively correlated with BP(P) values in Lt. LOF and Lt. MFC, and Suspiciousness positively correlated in LOF, Lt. LOF and Lt. MFC. Among female subjects alone, Negativism was positively correlated with BP(P) values in HIP, and Verbal Hostility in Lt. HIP. Altanserin binding in Lt. MTC was positively correlated with Persistence, with no significant gender effect. Gender differences in 5HT(2A) receptor function in specific ROIs may mediate expression of psychological characteristics such as aggression, suspiciousness and negativism. Future studies of 5HT(2A) receptor function and its relationship to behavior should control for gender.

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.

Comparison of Clinical Features and Personality Dimensions between Patients with Major Depressive Disorder and Normal Control

OBJECTIVE

Personality dimension is considered as a risk factor of depression. This study was to compare aggression, impulsivity, hopelessness, and TCI (temperament and character dimensions) between patients with major depressive disorder (MDD) and normal controls.

METHODS

A total of 56 MDD patients and the same number of normal controls who were matched for age, gender, and education were recruited. All subjects completed the following questionnaires; Aggression Questionnaire (AQ), Beck Hopelessness Scale (BHS), Barratt Impulsiveness Scale, 11th Version (BIS-11), and Temperament and Character Inventory (TCI).

RESULTS

MDD patients were significantly higher scores in anger, hostility of AQ, BHS, motor impulsivity of BIS-11, and Harm Avoidances (HA) of TCI with all subscales of HA than normal controls, whereas novelty seeking 1 (NS1) (Exploratory of NS), Reward Dependence (RD) with RD3 (Attachment) . RD4 (Dependence), Self-Directedness (SD) with most subscales of SD, Cooperativeness (CO), and ST3 (Spiritual Acceptance) showed lower scores than normal controls. Moreover, BHS and HA, BIS and NS showed moderate positive correlation in MDD patients, while BHS and SD, HA and SD were negatively correlated.

CONCLUSION

The present study showed unique clinical features, especially personality dimensions of patients with MDD. Our results could be applicable to suggest treatment process and to predict one's prognosis for depression in that psychological properties are important for drug compliance and treatment response.

[Which are the recent clinical findings regarding the association between depression and suicide?]

OBJECTIVE

Suicide is one of the leading causes of mortality worldwide, especially among young subjects. Suicide is considered the outcome of a multidimensional and complex phenomenon, which is a result of the interaction between several factors. The association between psychopathology and suicide has been extensively investigated. Major depression plays an important role among the psychiatric diagnoses associated with suicide. This finding seems to be confirmed by different study designs, and in distinct populations. The present paper aims to briefly review the recent findings regarding the suicide-related clinical features of depression. Moreover, strategies for suicide prevention were also reviewed.

REVIEW

Recent references were identified and grouped in order to illustrate the main contributions about depression and suicide. Briefly, the literature review stresses the high prevalence of major depression among subjects presenting suicide behaviors. Psychopathological traits, such as aggression and impulsivity play a relevant role in triggering suicidal behaviors. Strategies for suicide prevention were also reviewed in Brazil and internationally. In general, detection and treatment are effective in reducing suicide rates.

CONCLUSION

Studies regarding suicide behaviors have had a pragmatic approach, and generated a large body of evidence about correlates of suicide. However, these studies have not been able to provide a consistent theoretical explanation for this phenomenon. The recent adoption of modern strategies represents a possibility of enhancing the research capability of such studies. In order to be clinically useful, findings should make it possible to deepen the understanding over the experience of a suicidal person, as well as to design specific strategies for prevention and treatment in population subgroups.

Suicide

Suicide receives increasing attention worldwide, with many countries developing national strategies for prevention. Rates of suicide vary greatly between countries, with the greatest burdens in developing countries. Many more men than women die by suicide. Although suicide rates in elderly people have fallen in many countries, those in young people have risen. Rates also vary with ethnic origin, employment status, and occupation. Most people who die by suicide have psychiatric disorders, notably mood, substance-related, anxiety, psychotic, and personality disorders, with comorbidity being common. Previous self-harm is a major risk factor. Suicide is also associated with physical characteristics and disorders and smoking. Family history of suicidal behaviour is important, as are upbringing, exposure to suicidal behaviour by others and in the media, and availability of means. Approaches to suicide prevention include those targeting high-risk groups and population strategies. There are, however, many challenges to large-scale prevention, especially in developing countries.

Candidate endophenotypes for genetic studies of suicidal behavior

Twin, adoption, and family studies have established the heritability of suicide attempts and suicide. Identifying specific suicide diathesis-related genes has proven more difficult. As with psychiatric disorders in general, methodological difficulties include complexity of the phenotype for suicidal behavior and distinguishing suicide diathesis-related genes from genes associated with mood disorders and other suicide-associated psychiatric illness. Adopting an endophenotype approach involving identification of genes associated with heritable intermediate phenotypes, including biological and/or behavioral markers more proximal to genes, is an approach being used for other psychiatric disorders. Therefore, a workshop convened by the American Foundation for Suicide Prevention, the Department of Psychiatry at Columbia University, and the National Institute of Mental Health sought to identify potential target endophenotypes for genetic studies of suicidal behavior. The most promising endophenotypes were trait aggression/impulsivity, early-onset major depression, neurocognitive function, and cortisol social stress response. Other candidate endophenotypes requiring further investigation include serotonergic neurotransmission, second messenger systems, and borderline personality disorder traits.

Suicide and potential occupational exposure to pesticides, Colorado 1990-1999

A number of occupational studies have reported high rates of suicide among selected occupations, including farmers. Limited work has focused on occupational exposures that may increase the risk of suicide. The purpose of this study is to describe suicide among individuals potentially exposed to pesticides through their occupation. Data from Colorado death certificate files for the period 1990-1999 were obtained. Eligible records were those individuals who were Colorado residents at the time of death who had an occupation listed on their death certificates. Cases had suicide listed as the primary cause of death on the death certificates. The comparison group included Colorado residents who died from any cause during the same period other than cancer, mental disorders and injuries. A total of 4,991 suicide deaths were included and a total of 107,692 other deaths served as the comparison group. Occupations considered pesticide exposed included: veterinarians; pest control occupations; farmers and farm workers; farm managers and supervisors; marine life cultivators; nursery workers; groundskeepers and gardeners; animal caretakers; graders, sorters and inspectors of agricultural products; and forestry workers, supervisors and loggers. All other occupational categories were coded as unexposed. Logistic regression was used to compare the groups, separately for males and females. After controlling for age, race, Hispanic ethnicity, years of education, and marital status, males who were in pesticide exposed occupations had higher odds of suicide (odds ratio 1.14; 95% confidence interval 0.97, 1.34) and females in pesticide exposed occupations also had higher odds of suicide (odds ratio 1.98; 95% confidence interval 1.01, 3.88).

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.

Association study of two polymorphisms of the serotonin-2A receptor gene and suicide attempts

Serotonin (5-HT) receptors may have a role in suicidal behavior. Previous studies have shown an association between the T102C polymorphism of the 5-HT2a receptor gene and suicidal behavior. However, negative findings have also been reported. We examined the association between the T102C and C1354T (His452Tyr) polymorphisms of the 5-HT2a receptor gene and suicide attempts. Four hundred forty-one suicide attempters, 339 psychiatric patients, and 410 healthy controls were compared for genotypes of the T102C and C1354T (His452Tyr) polymorphisms. There were significant differences in the distribution of the three genotypes (TT, TC, and CC) of the T102C polymorphism in the three groups (controls, psychiatric patients, and suicide attempters). There was an excess of C/C genotypes in the suicide attempter group compared with the control group, but there were no significant differences between suicide attempters and psychiatric controls. We found no association between the C1354T polymorphism and suicide attempts. The C allele of the T102C polymorphism of the 5-HT2A receptor gene may be associated with biological susceptibility for suicidal behavior or psychiatric conditions.

Neurobiology of anorexia and bulimia nervosa

Anorexia nervosa (AN) and bulimia nervosa (BN) are related disorders of unknown etiology that most commonly begin during adolescence in women. AN and BN have unique and puzzling symptoms, such as restricted eating or binge-purge behaviors, body image distortions, denial of emaciation, and resistance to treatment. These are often chronic and relapsing disorders, and AN has the highest death rate of any psychiatric disorder. The lack of understanding of the pathogenesis of this illness has hindered the development of effective interventions, particularly for AN. Individuals with AN and BN are consistently characterized by perfectionism, obsessive-compulsiveness, and dysphoric mood. Individuals with AN tend to have high constraint, constriction of affect and emotional expressiveness, ahendonia and asceticism, whereas individuals with BN tend to be more impulsive and sensation seeking. Such symptoms often begin in childhood, before the onset of an eating disorder, and persist after recovery, suggesting they are traits that create a vulnerability for developing an ED. There is growing acknowledgement that neurobiological vulnerabilities make a substantial contribution to the pathogenesis of AN and BN. Considerable evidence suggests that altered brain serotonin (5-HT) function contributes to dysregulation of appetite, mood, and impulse control in AN and BN. Brain imaging studies, using 5-HT specific ligands, show that disturbances of 5-HT function occur when people are ill, and persist after recovery from AN and BN. It is possible that a trait-related disturbance of 5-HT neuronal modulation predates the onset of AN and contributes to premorbid symptoms of anxiety, obsessionality, and inhibition. This dysphoric temperament may involve an inherent dysregulation of emotional and reward pathways which also mediate the hedonic aspects of feeding, thus making these individuals vulnerable to disturbed appetitive behaviors. Restricting food intake may become powerfully reinforcing because it provides a temporary respite from dysphoric mood. Several factors may act on these vulnerabilities to cause AN to start in adolescence. First, puberty-related female gonadal steroids or age-related changes may exacerbate 5-HT dysregulation. Second, stress and/or cultural and societal pressures may contribute by increasing anxious and obsessional temperament. Individuals with AN may discover that reduced dietary intake, by reducing plasma tryptophan availability, is a means by which they can modulate brain 5-HT functional activity and anxious mood. People with AN enter a vicious cycle which accounts for the chronicity of this disorder because caloric restriction results in a brief respite from dysphoric mood. However, malnutrition and weight loss, in turn, produce alterations in many neuropeptides and monoamine function, perhaps in the service of conserving energy, but which also exaggerates dysphoric mood. In summary, this article reviews findings in brain chemistry and neuroimaging that shed new light on understanding the psychopathology of these difficult and frustrating disorders.

Suicide attempts in anorexia nervosa

OBJECTIVE

To explore prevalence and patterns of suicidal attempts in persons with anorexia nervosa (AN).

METHODS

Participants were the first 432 persons (22 male, 410 female) enrolled in the NIH funded Genetics of Anorexia Nervosa Collaborative Study. All participants had current or lifetime AN. The participants ranged in age from 16 to 76 (mean = 30.4, SD = 11.3). Suicidal behavior and intent was assessed via the Diagnostic Interview for Genetic Studies. We compared frequency and severity of attempts across diagnostic subtypes and comorbidity, and personality features associated with the presence of suicide attempts in persons with AN.

RESULTS

About 16.9% of those with AN attempted suicide. Significantly fewer persons with the restricting subtype (7.4%) reported at least one attempt than those with purging AN (26.1%), AN with binge eating (29.3%), and a mixed picture of AN and bulimia nervosa (21.2%). After controlling for major depression, suicide attempts were associated with substance abuse, impulsive behaviors and traits, Cluster B personality disorders, panic disorder, and post-traumatic stress disorder as well as low self-directedness and eating disorder severity.

CONCLUSIONS

Suicide attempts in AN are not uncommon, are frequently associated with the intention to die, occur less frequently in persons with the restricting subtype of the illness, and after controlling for depression are associated with a constellation of behaviors and traits associated with behavioral and affective dyscontrol.

Frontolimbic serotonin 2A receptor binding in healthy subjects is associated with personality risk factors for affective disorder

BACKGROUND

Serotonergic dysfunction has been associated with affective disorders. High trait neuroticism, as measured on personality inventories, is a risk factor for major depression. In this study we investigated whether neuroticism is associated with serotonin 2A receptor binding in brain regions of relevance for affective disorders.

METHODS

Eighty-three healthy volunteers completed the standardized personality questionnaire NEO-PI-R (Revised NEO Personality Inventory) and underwent [(18)F]altanserin positron emission tomography imaging for assessment of serotonin 2A receptor binding. The correlation between the neuroticism score and frontolimbic serotonin 2A receptor binding was evaluated by multiple linear regression analysis with adjustment for age and gender.

RESULTS

Neuroticism correlated positively with frontolimbic serotonin 2A receptor binding [r(79) = .24, p = .028]. Post hoc analysis of the contributions from the six constituent traits of neuroticism showed that the correlation was primarily driven by two of them: vulnerability and anxiety. Indeed, vulnerability, defined as a person's difficulties in coping with stress, displayed the strongest positive correlation, which remained significant after correction for multiple comparisons (r = .35, p = .009).

CONCLUSIONS

In healthy subjects the personality dimension neuroticism and particularly its constituent trait, vulnerability, are positively associated with frontolimbic serotonin 2A binding. Our findings point to a neurobiological link between personality risk factors for affective disorder and the serotonergic transmitter system and identify the serotonin 2A receptor as a biomarker for vulnerability to affective disorder.

SPECT neuroimaging in translational research of CNS disorders

High resolution SPECT imaging is an emerging field and there are only limited studies as yet available in this direction. Still there is continuous effort to achieve better spatial and temporal resolution in order to obtain detailed structural and functional information of different brain regions in small experimental animals. Recently, SPECT imaging system has been used to perform in vivo imaging using specific radioligands to further elucidate the role of dopaminergic, serotonergic, and cholinergic neurotransmission in relation to regional cerebral blood flow in various human CNS disorders and in gene-manipulated mouse models of neurodegeneration. Although in vivo and non-invasive translational research can be performed by high-resolution microPET imaging system, its limited spatial resolution restricts detailed anatomical and functional information of different brain regions involved in disease process. Recently developed NanoSPECT/CT imaging system has a better spatial resolution hence can be used to correlate and confirm microPET imaging data and determine the precise structural and functional anatomy of CNS disorders and their remission. Moreover SPECT imaging system reduces the cost and number of animals and provides detailed information of CNS disorders at the cellular, molecular and genetic level. Furthermore, SPECT system is economical, provides less radiation burden, and can be used to study bio-distribution of newly synthesized radioligands with increased target to non-target ratios, quality control, and clinical applications. It is envisaged that high-resolution SPECT imaging system will further improve in vivo non-invasive translational research on CNS disorders of unknown etiopathogenesis and their treatment in future.

The Swedish Version of the Temperament and Character Inventory (TCI)

Abstract. In order to establish new norms of the Swedish version of the Temperament and Character Inventory (TCI), data from 2,209 Swedish individuals (age between 13 and 80) was analyzed. The second aim was to evaluate the impact of age and gender on the questionnaire scores. The third aim was to investigate whether the TCI can be meaningfully applied to adolescents in personality assessment as a basis for further research and clinical studies. Age and gender showed independent effects on personality dimensions, which implies that age and gender specific norms have to be established for the TCI. Furthermore, the results in terms of inconsistencies in the correlational and factorial structure, as well as low internal consistency scores in the younger age groups, suggest that the adult version of the TCI should not be applied below the age of 17; for these age groups we recommend the use of the junior TCI (JTCI). The inventory is under further development and several items are in need of revision in order to create less complicated formulations, enabling an improvement in the psychometrics.

Neurobiology of suicidal behavior. An integration of biological and clinical findings

Suicide is among the top ten leading causes of death in individuals of all ages. An explanatory model for suicidal behavior that links clinical and psychological risk factors or endophenotypes, to the underlying neurobiological abnormalities associated with suicidal behavior may enhance prediction, help identify treatment options and have heuristic value. Our explanatory model proposes that developmental factors that are biological (genetics) and psychological or clinical (early childhood adversity) may have causal relevance to the disturbances found in subjects with suicidal behavior. In this way, our model integrates findings from several perspectives in suicidology and attempts to explain the relationship between various neurobiological, genetic, and clinical observations in suicide research, offering a comprehensive hypothesis to facilitate understanding of this complex outcome.

Polymorphism of the 5-HT(2A) receptor gene: association with stress-related indices in healthy middle-aged adults

Past research has concentrated on the stress system and personality in order to explain the variance found in cognitive performance in old age. A growing body of research is starting to focus on genetic polymorphism as an individual difference factor to explain the observed heterogeneity in cognitive function. While the functional mechanism is still under investigation, polymorphism of the 5-HT(2A) receptor gene (-1438A/G) has been linked to certain behavioral and physiological outcomes, including cortisol secretion, the expression of certain personality traits, and memory performance. It was the goal of the present study to investigate the association between the -1438A/G polymorphism and stress hormone secretion, stress-related psychological measures, and cognitive performance in a group of adults between the ages of 50 and 65. To examine these associations, 101 middle-aged adults were recruited, completed a battery of psychological questionnaires and were administered a battery of cognitive tasks that assess frontal lobe and hippocampal function. Basal and stress-reactive salivary cortisol levels were collected, at home and in the laboratory. Analyses on psychological measures showed that participants with the GG genotype reported significantly higher levels of neuroticism compared to the AG group and higher levels of depression and more emotion-based coping strategies compared to both the AG and AA group. In terms of cortisol secretion, the AA genotype was related to a significantly higher awakening cortisol response (ACR) compared to the AG and GG group and the GG genotype group displayed a greater increase in cortisol secretion following a psychosocial stressor compared to the two other groups. On measures of cognitive performance, the AA genotype group performed significantly better on a test of declarative memory and selective attention compared to the other two groups. Together, these results suggest that carriers of the GG genotype are more susceptible to low mood and display a greater potential for an overactive stress system, which may influence cognitive function in later years.

The influence of urban/rural residency on depressive symptoms is moderated by the serotonin receptor 2A gene

Gene-environment interactions are thought to be involved in the development of depression. Here we examined the interaction effect between urban/rural residency and the serotonin receptor 2A (HTR2A) gene on subclinical depressive symptoms. The participants were 1,224 Finnish men and women being followed in the on-going population-based study of "Cardiovascular Risk in Young Finns". Urban/rural residency was determined on the basis of a (1) subjective report and (2) the population density of the residential area. Depressive symptoms were measured in two test settings four years apart. There was a significant gene-environment interaction, such that the urban residency was associated with low depressive symptoms in individuals carrying the T/T or T/C genotype of the T102C polymorphism, but not in those carrying the C/C genotype. The T allele was associated with high depressive symptoms in remote rural areas, but with low depressive symptoms in urban or suburban areas. The gene-environment interaction was not accounted by level of education, social support, unemployment, or partnership status. The HTR2A gene may be involved in the development of depression by influencing how individuals respond to environmental conditions.

5-HT2A: its role in frontally mediated executive function and related psychopathology

Serotonin (5-HT)2A receptors are widely distributed, with high levels in the frontal cortex, where postsynaptic activation may increase activity in pyramidal glutamatergic neurons and mediate various executive functions. More specifically, reciprocal cortical-raphe pathways may allow the ventral prefrontal cortex to inhibit stress-induced neural activity in the brainstem when stressors are perceived as controllable. However, early adversity and negative attitudes may be associated with higher frontal 5-HT2A receptor levels and greater risk for stress-induced psychopathology, and certain 5-HT2A gene variants have been associated with increased risk for impulsive behavior. Conversely, many antidepressants result in decreased levels of 5-HT2A receptor levels, and blockade of 5-HT2A receptors has proven useful in the treatment of a number of psychiatric disorders.

The Serotonin Receptor 2A Gene Moderates the Influence of Parental Socioeconomic Status on Adulthood Harm Avoidance

We examined whether the T102C polymorphism of the serotonin receptor 2A gene (HTR2A) moderated the influence of childhood or adolescence parental socioeconomic status (SES) on adulthood temperament trait harm avoidance (HA) in a population-based sample of 1246 healthy Finnish men and women, who were 24-39 years of age in the last follow-up phase. High parental SES predicted low adulthood HA. In addition, the C allele of the T102C polymorphism was associated with high HA in one of the two test settings, and with the mean of the two measurements. Most importantly, we found that the T102C polymorphism moderated the influence of parental SES, such that high parental SES predicted low adulthood HA in subjects with the T/T or T/C genotypes, while this was not true for those carrying the C/C genotype. The role of the T102C polymorphism was most pronounced among those with high parental SES. We conclude that the T102C polymorphism of the HTR2A gene may be involved in the development of temperament by moderating the influence of environmental conditions.

Exaggerated 5-HT1A but normal 5-HT2A receptor activity in individuals ill with anorexia nervosa

BACKGROUND

Many studies have found disturbances of serotonin (5-HT) activity in anorexia nervosa (AN). Because little is known about 5-HT receptor function in AN, positron emission tomography (PET) imaging with 5-HT receptor-specific radioligands was used to characterize 5-HT1A and 5-HT2A receptors.

METHODS

Fifteen women ill with AN (ILL AN) were compared with 29 healthy control women (CW); PET and [11C]WAY100635 were used to assess binding potential (BP) of the 5-HT1A receptor, and [18F]altanserin was used to assess postsynaptic 5-HT2A receptor BP. [15O] water and PET were used to assess cerebral blood flow.

RESULTS

The ILL AN women had a highly significant (30%-70%) increase in [11C]WAY100635 BP in prefrontal and lateral orbital frontal regions, mesial and lateral temporal lobes, parietal cortex, and dorsal raphe nuclei compared with CW. The [18F]altanserin BP was normal in ILL AN but was positively and significantly related to harm avoidance in suprapragenual cingulate, frontal, and parietal regions. Cerebral blood flow was normal in ILL AN women.

CONCLUSIONS

Increased activity of 5-HT1A receptor activity may help explain poor response to 5-HT medication in ILL AN. This study extends data suggesting that 5-HT function, and, specifically, the 5-HT2A receptor, is related to anxiety in AN.

Regional brain serotonin and dopamine transporter binding capacity in suicide attempters relate to impulsiveness and mental energy

To study different aspects of regional pre-synaptic brain (123)I-beta-CIT uptake on serotonin and dopamine re-uptake sites in drug-free suicide attempters in comparison with age- and sex matched control subjects, single photon emission computed tomography (SPECT) measurements were analysed for regional serotonin re-uptake (5HTT) and dopamine re-uptake (DAT) capacity (binding potential, BP()) after i.v. (123)I-beta-CIT administration. All suicide attempters were examined concerning seriousness of the attempt, and DSM-IV diagnosis. Both suicide attempters and control subjects were tested for psychotropic drugs, and completed the Marke-Nyman Temperament (MNT) test, including solidity (level of impulsiveness/initiative) and validity (level of mental energy). We found no significant difference between suicide attempters and control subjects concerning the regional levels of 5HTT BP() or DAT BP(). However, in suicide attempters, but not controls, we found significant regional correlations between MNT variables and SPECT results. We interpret the discrepant findings in suicide attempters and control subjects to be due to a disability of the suicide attempters to regulate their serotonin and dopamine levels, e.g. in response to external stress.

Serotonin 2A receptor gene is associated with personality traits, but not to disorder, in patients with borderline personality disorder

Borderline personality disorder (BPD) is a chronic, disabling, and high-risk mental disorder characterized by a pervasive pattern of instability in regulation of emotion, interpersonal relationships, self-image, and impulse control beginning in early adulthood. BPD affects about 1%-2% of the general population and has a high mortality rate as a result of suicide and impulsive behaviour. The serotonin 2A receptor gene (HTR2A) is considered a candidate gene for BPD because multiple lines of evidence suggest that it plays an important role in suicide, impulsivity and emotional liability. To test for an association between HTR2A and BPD, we genotyped four polymorphisms, rs6313 (T102C), rs4941573, rs2296972 and rs6314 (His452Tyr), in 111 Caucasian patients with BPD and 287 Caucasian healthy controls. The program UNPHASED was used to compare allele and haplotype frequencies between cases and controls. We did not find a significant association between HTR2A and BPD based on allele, genotype or haplotype analyses. However, there were significant associations between HTR2A and personality traits in the BPD patients. The C allele of rs6313 and the A allele of rs4941573 associated with a higher Extraversion score. Our results suggest that the serotonin 2A receptor gene may not play a major role in the aetiology of borderline personality disorder, but may have a role in personality traits.

Association study of seven polymorphisms in four serotonin receptor genes on suicide victims

A number of molecular genetic studies have investigated if serotonin (5-HT) receptor subtypes are involved in the pathogenesis of depression, suicidal behavior, aggression, and impulsive behavior. Existence of many receptor subtypes for a single transmitter permits a great diversity of signaling raising the possibility that they may serve as genetic markers for suicidal behavior. Most previous studies of suicide have analyzed polymorphisms of the receptors 5-HT1A, 5-HT1B, 5-HT2A, fewer have examined 5-HT1F. We report a study of possible association between the polymorphisms in the 5-HT receptor genes (1A, 1B, 1F, and 2A) and suicidal behavior on a sample of 226 suicide victims and 225 healthy control subjects. No significant differences in genotype frequency distributions between the suicide victims and healthy control subjects were observed for four polymorphisms; three were not polymorphic. A single polymorphism, C-1420T in gene 5-HT2A, showed a slight association with suicide (chi2= 4.94, df = 2, P = 0.067), but the correlation was not statistically significant. None of the tested genetic variants of serotonin receptors appears to be associated with suicidal behavior in the Slovenian population which has a relatively high suicide rate.

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

An imbalance of the immune system and mixed personality profiles in suicide attempters have been reported. As suicidal behavior is common in patients with psychiatric disorders within the spectrum of depressive features, in this study we measured soluble interleukin-2 receptor concentrations in plasma (sIL-2R) and investigated temperament and character profile and their potential correlation in formerly depressed patients with a history of suicide attempt. We studied sIL-2R levels in plasma and personality characteristics (using Cloninger's Temperament and Character Inventory [TCI]) of formerly depressed patients who had attempted suicide a mean of 3 years previously (n = 25), and age and gender matched normal controls (n = 25). There was no significant difference in sIL-2R levels between formerly depressed suicide attempters and age and gender matched normal controls (0.23 ng/ml +/- 0.25 vs. 0.19 ng/ml +/- 0.16). When compared to normal controls, suicide attempt patients had a significantly higher score on the temperament dimension "harm avoidance" and a lower score on the character dimension "self-directedness." No significant correlation was found between sIL-2R values and TCI dimensions. We propose that the liability to suicidal behavior among suicide attempters susceptible to depressive symptomatology may be related to high harm avoidance and low self-directedness.

Involvement of diazepam-insensitive benzodiazepine receptors in the suppression of DOI-induced head-twitch responses in diabetic mice

RATIONALE

We previously reported that the head-twitch responses induced by the 5-HT2 receptor agonist (+/-)-2,5-dimethoxy-4-iodoamphetamine (DOI) (DOI-HTRs) were decreased in streptozotocin-induced diabetic mice.

OBJECTIVES

We examined the involvement of gamma-aminobutyric acid (GABA)/benzodiazepine system on the suppression of DOI-HTRs in diabetic mice.

RESULTS

The benzodiazepine receptor antagonist flumazenil (0.1-1 mg/kg, i.v.) dose-dependently and significantly increased DOI-HTRs in diabetic mice to the same levels as in nondiabetic mice. However, flumazenil (0.1-1 mg/kg, i.v.) did not affect DOI-HTRs in nondiabetic mice. The benzodiazepine receptor agonist diazepam (0.1-1 mg/kg, i.p.) had no effect on DOI-HTRs in either nondiabetic or diabetic mice. The GABAA receptor antagonist bicuculline (0.1-1 mg/kg, i.p.) and the benzodiazepine receptor partial inverse agonist Ro 15-4513 (0.1-1 mg/kg, i.v.) dose-dependently and significantly suppressed DOI-HTRs in nondiabetic mice to the same levels as in diabetic mice. Ro 15-4513-induced reduction of DOI-HTRs in nondiabetic mice was completely antagonized by flumazenil (1 mg/kg, i.v.), but not diazepam (0.3 mg/kg, i.p.).

CONCLUSIONS

We suggest that the abnormal diazepam-insensitive benzodiazepine receptor function partly underlies the suppression of DOI-HTRs in diabetic mice.

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.

Psychological, autonomic, and serotonergic correlates of parasuicide among adolescent girls

Although parasuicidal behavior in adolescence is poorly understood, evidence suggests that it may be a developmental precursor of borderline personality disorder (BPD). Current theories of both parasuicide and BPD suggest that emotion dysregulation is the primary precipitant of self-injury, which serves to dampen overwhelmingly negative affect. To date, however, no studies have assessed endophenotypic markers of emotional responding among parasuicidal adolescents. In the present study, we compare parasuicidal adolescent girls (n=23) with age-matched controls (n=23) on both psychological and physiological measures of emotion regulation and psychopathology. Adolescents, parents, and teachers completed questionnaires assessing internalizing and externalizing psychopathology, substance use, trait affectivity, and histories of parasuicide. Psychophysiological measures including electrodermal responding (EDR), respiratory sinus arrhythmia, and cardiac pre-ejection period (PEP) were collected at baseline, during negative mood induction, and during recovery. Compared with controls, parasuicidal adolescents exhibited reduced respiratory sinus arrhythmia (RSA) at baseline, greater RSA reactivity during negative mood induction, and attenuated peripheral serotonin levels. No between-group differences on measures of PEP or EDR were found. These results lend further support to theories of emotion dysregulation and impulsivity in parasuicidal teenage girls.

Combined Treatment for Social Anxiety Disorder

Despite scant evidence of an advantage of combining medication and cognitive behavioral therapy (CBT) for social anxiety disorder, the advantages and disadvantages of the two approaches suggest the possibility that some form of combination may be helpful for many clients. At the same time, the available evidence and theoretical considerations suggest that some methods of combination could provide short-term benefits but long-term decreases in efficacy compared to either treatment alone. Thus, current knowledge suggests that, for social anxiety disorder, more treatment is no substitute for well-informed treatment. We provide guidelines for treatment based on available evidence, theoretical models, and clinical experience. Overall, the clearest case for combination treatment is for the addition of an empirically supported CBT for social anxiety disorder following the stabilization of response to an empirically supported psychopharmacological agent. The CBT should then be modified to address the use of medication, the possibility of relapse, and, ideally, the tapering of medication during CBT. Further research is called for in order to support these recommendations and extend the available literature.