DST non-suppression predicts suicide after attempted suicide

Childhood trauma cortisol and immune cell glucocorticoid transcript levels are associated with increased risk for suicidality in adolescence

Rising adolescent suicide rates present a growing unmet need. Childhood trauma (CT) has been associated with altered cortisol dynamics and immune cell glucocorticoid reactivity, yet their additive longer-term contributions to later suicide outcomes are less clear. The current study compared CT scores, resting salivary free cortisol and mononuclear cell gene expression levels of the nuclear receptor, subfamily 3, member 1 (NR3C1) coding the glucocorticoid receptor, and its co-chaperons FKBP prolyl isomerase 5 (FKBP5) and KIT Ligand (KITLG), between a cohort of adolescents presenting with a suicidal crisis requiring hospital treatment, and matched healthy controls. Childhood trauma scores and glucocorticoid measures were significantly altered among suicidal adolescents, and CT scores correlated with mononuclear cell glucocorticoid transcripts. Both CT scores and glucocorticoid measures explained substantial additive portions of the variance in adolescent suicidality. Long-term perturbations in cortisol dynamics and immune cell glucocorticoid response elements denote dysregulated immune stress reactivity, and may possess value in prediction and point to modifiable-risk factors in prevention of clinically significant suicidality during the brittle period of adolescence, years after childhood trauma exposure.

The dexamethasone suppression test as a biomarker for suicidal behavior: A systematic review and meta-analysis

BACKGROUND

The dexamethasone suppression test (DST), which measures HPA-axis functioning, is a potential biomarker for suicidal behavior. The current study aimed (a) to synthesize available knowledge on the association between DST non-suppression and suicidal behavior, and (b) to study potential moderators.

METHODS

A total of 4236 studies were screened, 43 were included. Suicide attempts and suicide completion were studied separately. The meta-analysis included 37 effect sizes for suicide attempts (n = 3733) and 11 effect sizes for suicide completion (n = 1626).

RESULTS

DST non-suppression was associated with completed suicide (odds ratio (OR) = 2.10, (95 % CI [1.37, 3.23]). For suicide attempts, we found no evidence that DST status was associated in the overall meta-analysis including all patient samples. However, moderator analysis indicated that the DST status was associated with suicide attempts in patient samples that included psychopathology other than just mood disorders, such as psychotic, substance use and personality disorders (OR = 2.34, 95 % CI [1.39-3.93], k = 11).

LIMITATIONS

The potential influence of publication bias and exclusion of some relevant published studies (since effect sizes could not be calculated, authors could not supply data or authors could not be reached) are limitations. Furthermore, missing moderator data decreased our ability to explain heterogeneity between studies.

CONCLUSIONS

The results of this meta-analysis support the hypothesis that DST non-suppression is predictive of suicidal behavior. More research is needed to investigate optimal cut-off values, confounding factors and the potential usefulness of the DST in clinical practice in terms of personalized medicine.

Suicidal ideation, plan, and attempt among men who have sex with men in Nepal: Findings from a cross-sectional study

Men who have sex with men (MSM) are at increased risk for suicide, with a much higher prevalence of suicidality than the general population. While there is a growing interest in the identification of risk factors for suicidal behaviors globally, the understanding of the prevalence and risk factors for suicidal behaviors among MSM in the context of low- and middle-income countries is almost non-existent. Therefore, this study aimed to investigate suicidal ideation, plan, and attempts, and related factors among MSM in Nepal. A cross-sectional respondent driven survey was conducted on 250 MSM between October and December 2022. Bivariate and multivariable logistic regression was used to evaluate independent correlates of suicidal behaviors of MSM. Overall, the lifetime prevalence of suicidal ideation, plans, and attempts among MSM in this study were 42.4%, 31.2%, and 21.6%, respectively. MSM with depressive symptoms (aOR = 5.7, 95% CI = 2.4-14.1), advanced education (higher secondary and above; aOR = 2.9, 95% CI = 1.4-6.1), and smoking habit (aOR = 2.5, 95% CI = 1.2-5.3) were at increased risk for suicidal ideation. Similarly, those with depressive symptoms (aOR = 2.2, 95% CI = 1.1-4.8) and advanced education (aOR = 2.7, 95% CI = 1.2-5.7) were more likely to plan suicide, whereas young MSM were significantly more prone to attempting suicide (aOR = 2.7, 95% CI = 1.3-5.8). Interestingly, MSM with moderate to severe food insecurity were 2-3 times more likely to think about, plan, or attempt suicide (ideation: aOR = 3.5, 95% CI = 1.6-7.7; plan: aOR = 3.7, 95% CI = 1.6-8.3; attempt: aOR = 2.2, 95% CI = 1.1-4.6). The results suggest the importance of early assessment of suicidal behaviors among MSM and the need for tailored interventions to simultaneously address mental health problems and food insecurity to reduce suicide-related problems among Nepalese MSM.

HPA-axis dysregulation is not associated with accelerated epigenetic aging in patients with hypersexual disorder

BACKGROUND

Hypersexual disorder (HD) - a nonparaphilic sexual desire disorder with impulsivity component - was evaluated for inclusion as a diagnosis in the DSM-5 and the diagnosis compulsive sexual behavior disorder is included as an impulse control disorder in the ICD-11. Hypothalamic-pituitary-adrenal (HPA)-axis hyperactivity is believed to affect cellular senescence and has been implicated in HD. No previous study investigated HD or HPA-axis dysregulation in relation to measures of epigenetic age (EA) acceleration.

METHODS

This study reports on a case-control study set-up from a well-characterized cohort, contrasting EA predictors in relation to 60 HD patients and 33 healthy volunteers (HV) and 19 mixed HD/HV exhibiting dexamethasone suppression test (DST) non-suppression to 73 mixed HD/HV DST controls. The genome-wide methylation pattern was measured in whole blood from 94 subjects using the Illumina Infinium Methylation EPIC BeadChip and preprocessed according to specialized protocols suitable for epigenetic age estimation. The online DNAm Age Calculator (https://dnamage.

GENETICS

ucla.edu/) was implemented to retrieve various EA predictors, which were compared between the in-silico generated subgroups.

RESULTS

Quality control analyses indicated strong correlations between the EA measure DNA methylation GrimAge (DNAm GrimAge - the EA clock most reliably associated with mortality risk) and chronological age in all sub-groups. The study was adequately powered to detect differences of 2.5 and 3.0 years in DNAm GrimAge minus age in relation to both HD and HPA-axis dysregulation, respectively. Baseline DNAm GrimAge exceeded chronological age by 2.8 years on average across all samples. No EA acceleration marker was associated with HD or DST suppression status (p > 0.05).

CONCLUSION

EA acceleration markers shown to be strongly predictive of physiological dysregulation and mortality-risk, are not related to HD or DST non-suppression status (measured after 0.5 mg dexamethasone). The independency of HPA-axis dysregulation to EA acceleration does not support the biological relevance of this dosage-regimen when applied to patients with HD. These findings do not support the notion of accelerated cellular senescence in HD. Studies stratifying DST non-suppressors according to established dosage-regimens in somatic settings are needed to fully elucidate the putative contribution of HPA-axis dysregulation to EA.

Blood hormones and suicidal behaviour: A systematic review and meta-analysis

This study was to evaluate the relationship between blood hormone levels and suicidal behaviour. We reviewed Web of Science, PubMed and Embase for literature published up to 10 April 2022. Studies were restricted to English-language articles. Studies measuring blood hormone levels in suicidal and non-suicidal subjects were eligible. Standardized mean differences (SMDs) were applied to evaluate group differences. Overall, 57 studies were eligible, of which 51 evaluated suicide attempts, and 9 assessed suicidal ideation. Random-effects meta-analysis indicated that levels of thyrotropin stimulating hormone (TSH) (SMD = 0.50; 95% CI, 0.27-0.72), leptin (SMD = -1.16; 95% CI, -1.94 to -0.38) and dehydroepiandrosterone sulfate (DHEAS) (SMD = -0.67; 95% CI, -1.13 to -0.21) were related to suicide attempts, whereas progesterone levels (SMD = 0.22; 95% CI, 0.03-0.41) were related to suicidal ideation. This analysis offers evidence linking abnormalities of blood hormones with suicidal behaviour, which may be essential for identifying individuals with suicide attempts and suicidal ideation. Large prospective studies are needed for further clarification of roles of hormones in suicidal behaviour.

Non-Suicidal Self-Injury in Russian Patients with Suicidal Ideation

BACKGROUND

Nonsuicidal self-injury (NSSI) is recognized as a public health concern for its association with unfavorable outcomes, including suicidal behavior. The aim of this study is to identify factors associated with NSSI among patients with nonpsychotic mental disorders (NPMD) and suicidal ideation in Russia.

METHODS

A retrospective cohort study was conducted in the Moscow Research and Clinical Center for Neuropsychiatry between November 2017 and May 2019. The sample was composed of consecutive patients with lifetime suicidal ideation (from the Self-Injurious Thoughts and Behavior Interview) seen in the center's psychiatric ward for NPMD. The patients were divided into two groups: those with and without lifetime NSSI. Sociodemographic variables, psychiatric diagnosis, family history of mental disorders, history of physical or sexual abuse, sexual behavior, ad-hoc psychiatric treatments, suicidal ideation, plans, and gestures or attempts were investigated.

RESULTS

Six thousand, two hundred and four consecutive patients were screened for suicidal ideation. Out of a total of 361 patients (87.3% females) with suicidal ideation, 217 (60.1%) reported NSSI. Variables independently associated with NSSI included age <25 years (OR 6.0, CI 2.5-14.7), dissatisfaction with the perceived parenting style (OR 3.3, CI 1.5-7.4), bullying (OR 2.6, CI 1.0-6.5), severe body modifications (OR 11.9, CI 1.1-134.3), experience with illicit drugs (OR 4.4, CI 1.9-10.3), and eating disorders (OR 4.9, CI 2.0-11.8).

LIMITATIONS

Retrospective design, referral population, single center study, and exclusion of psychotic patients.

CONCLUSIONS

NSSI is associated with age <25 years old, dissatisfaction with perceived parenting style, bullying, severe body modifications, lifetime experience of illicit drug-use, and lifetime eating disorders.HIGHLIGHTSNonsuicidal self-injury is a significant public health concern for its association with suicidal behavior.60.1% of Russian patients with non-psychotic mental disorders (NPMD) and suicidal ideation reported lifetime NSSI.NSSI in Russian patients with NPMD and suicidal ideation is associated with age less than 25 years, dissatisfaction with perceived parenting style, bullying, severe body modifications, lifetime experience of illicit drug use, and lifetime eating disorders.

Neurochemical and Hormonal Contributors to Compulsive Sexual Behavior Disorder

Purpose of Review

Compulsive sexual behavior disorder has been recently included in the 11th revision of the International Classification of Diseases (ICD-11), and the possible contribution of neurochemical and hormonal factors have been reported. However, relatively little is known concerning the neurobiology underlying this disorder. The aim of this article is to review and discuss published findings in the area.

Recent Findings

Evidence suggests that the neuroendocrine systems are involved in the pathophysiology of compulsive sexual behavior. The hypothalamus-pituitary adrenal axis, the hypothalamus-pituitary–gonadal axis, and the oxytocinergic system have been implicated.

Summary

Further studies are needed to elucidate the exact involvement of neuroendocrine and hormonal systems in compulsive sexual behavior disorder. Prospective longitudinal studies are particularly needed, especially those considering co-occurring psychiatric disorders and obtaining hormonal assessments in experimental circumstances with appropriate control groups.

Recurrent suicide attempts affect normalization of HPA axis dysregulation after recovery from major depression

More than 700,000 people worldwide die by suicide every year, and the number of suicide attempts is estimated as 20 times higher, most of them being associated with psychiatric disorders, especially major depression. Knowledge about effective methods for preventing suicide attempts in individuals at high risk for suicide is still scarce. Dysregulation of the neuroendocrine stress response system, i.e., the hypothalamic-pituitary-adrenocortical (HPA) axis, is one of the most consistent neurobiological findings in both major depression and suicidality. While the HPA axis is mostly overactive in depression, individuals with a history of suicide attempts exhibit an attenuated hormonal response to stress. It is unknown, however, whether the HPA axis is constantly attenuated in repeated suicide attempters or whether it regains normal responsivity after recovery from depression. Using the combined dexamethasone suppression/corticotropin-releasing hormone (dex/CRH) test, we assessed HPA axis regulation in acute depression (N = 237) and after recovery with respect to previous suicide attempts. Patients without previous suicide attempts show normalization of the stress hormone response to the second dex/CRH (basal ACTH response and cortisol response) after recovery from acute depression, while patients with multiple previous SA show an increased ACTH response. The change in HPA axis responsivity in patients with only one previous SA lies between the response patterns of the other groups with no change in HPA axis reactivity. Our findings suggest that patients with a history of suicide attempts belong to a subgroup of individuals that exhibit a distinct pattern of stress hormone response during acute depression and after recovery. Future studies may extend our approach by investigating additional psychological stress tasks to gain a broader understanding of the stress pathology of recurrent suicide attempters.

Effects of weariness of life, suicide ideations and suicide attempt on HPA axis regulation in depression

The neuropathological mechanisms leading to suicidality are still unknown, which, in view of an annual toll of around 1 million completed suicides constitutes an urgent clinical and societal problem. Alterations of stress hormone (ACTH and cortisol, representing the activity of the hypothalamic-pituitary-adrenocortical, HPA axis) regulation has been repeatedly studied in context of suicidality. Following a suicide attempt, stress hormone activity seems to be blunted, while depressed patients with suicidal ideation often present with elevated HPA axis activity.

METHODS

We investigated the effects of different forms of suicidality on HPA axis regulation in 568 hospitalized patients of the Munich Antidepressant Response Signature (MARS) project. All patients had a diagnosis of a depressive disorder; 62 patients reported a recent suicide attempt, 192 patients suicide ideation, and 171 patients expressed weariness of life as the weakest form of suicidality, the latter not being analyzed in studies so far. All patients participated in the combined dexamethasone/corticotropin releasing hormone (dex/CRH) test for assessing HPA axis regulation shortly after admission to the hospital.

RESULTS

We found an increased ACTH and cortisol response following the dex/CRH-test in patients that were weary of life. In contrast, stress hormone response in suicide attempters and suicide ideators did not differ from non-suicidal patients. Further, repeated suicide attempts in patients' history were associated with more pronounced stress hormone attenuation.

CONCLUSION

In this so far largest study analyzing the HPA axis with respect to suicidality, we could not confirm the assumption of a general attenuation of HPA axis response in depressed suicide ideators and attempters. Conversely, HPA axis appears to be influenced by divergent effects of a specific suicidal psychopathology as well as outlasting effects of previous suicide attempts. We discuss these findings in the light of recent concepts of suicidality, pointing to multifactorial effects of acute and predisposing conditions on HPA axis reactivity in depressed patients.

Proposal for the Inclusion of Tobacco Use in Suicide Risk Scales: Results of a Meta-Analysis

There is an association between smoking and suicide, even though the direction and nature of this relationship remains controversial. This meta-analysis aimed to evaluate the association between smoking and suicidal behaviours (ideation, planning, suicide attempts, and death by suicide). On 24 August 2020, we searched the PubMed, Cochrane library, Scopus, Web of Science, TRIP, and SCIENCE DIRECT databases for relevant articles on this topic. Twenty prospective cohort studies involving 2,457,864 participants were included in this meta-analysis. Compared with never smokers, former and current smokers had an increased risk of death by suicide (relative risk [RR] = 1.31; 95% CI [1.13, 1.52] and RR = 2.41; 95% CI [2.08, 2.80], respectively), ideation (RR = 1.35; 95% CI [1.31, 1.39] and RR = 1.84; 95% CI [1.21, 2.78]), and attempted suicide (RR = 1.27; 95% CI [0.56, 2.87] and RR = 1.71; 95% CI [0.73, 3.97]). Moreover, compared to never smokers, current smoker women (RR = 2.51; 95% CI [2.06-3.04] had an increased risk of taking their own life (Q = 13,591.53; p < 0.001) than current smoker men (RR = 2.06; 95% CI [1.62-2.62]. Furthermore, smoking exposure (former and current smokers) was associated with a 1.74-fold increased risk (95% CI [1.54, 1.96]) of suicidal behaviour (death by suicide, ideation, planning, or attempts). Thus, because of the prospective relationship between smoking and suicidal behaviours, smoking should be included in suicide risk scales as a useful and easy item to evaluate suicide risk.

Ex vivo glucocorticoid receptor-mediated IL-10 response predicts the course of depression severity

Directly measuring hypothalamic pituitary adrenal (HPA) axis function, an important player in affective disorders, is intensive and invasive. A crucial component of this system, the activity of the glucocorticoid receptor (GR), can be assessed ex vivo instead. Here, we investigated GR sensitivity in patients with major depressive disorder (MDD) to determine its predictive potential. Psychometric data and blood samples were collected from patients experiencing a major depressive episode (MDE, n = 87), healthy control subjects (n = 49), and patients with remitted MDD (n = 31) at baseline and (for patients) after median 20 days of follow-up after treatment as usual. Blood cells were stimulated ex vivo with lipopolysaccharide and the effect was suppressed by increasing dexamethasone (DEX) concentrations. The resultant cytokine secretion profile (for IL-6, IL-10, and TNF-α) was considered indicative of GR activity. Higher baseline scores of the Montgomery–Åsberg Depression Rating Scale (MADRS) were associated with a stronger decrease of logIC IL-6 (indicating an increase of GR sensitivity). Higher baseline logEC IL-10 (indicating a lower GR sensitivity) and a stronger reduction of logEC IL-10 (indicating a stronger increase in GR sensitivity) were associated with a stronger decrease in the MADRS score. Patients with remitted MDD showed higher logIC TNF-α values (indicating lower GR sensitivity) in comparison to patients with a current MDD at baseline and follow-up. Initially low GR sensitivity measured ex vivo in peripheral blood cells that increases over the course of treatment could serve as a predictive marker for stronger improvement in depression severity.

The Association Between Suicide Attempts, Anxiety, and Childhood Maltreatment Among Adolescents and Young Adults With First Depressive Episodes

Objective: Adolescents and young adults are susceptible to high-risk behaviors such as self-harm and suicide. However, the impact of childhood maltreatment on suicide attempts in adolescents and young adults with first episode of depression remains unclear. This study examined the association between suicide attempts and childhood maltreatment among adolescents and young adults with first depressive episodes. Methods: A total of 181 adolescents and young adults with first depressive episodes were included. The Child Trauma Questionnaire (CTQ), Beck Anxiety Inventory (BAI), and Patient Health Questionnaire-2 (PHQ-2) were used to assess childhood maltreatment and the severity of anxiety and depressive symptoms, respectively. The suicide item in the MINI-International Neuropsychiatric Interview (M.I.N.I.) 5.0 was used to assess the suicide attempts. Logistic regression analyses were used to explore the associated factors of suicide attempts. Results: The prevalence of SA in the total sample was 31.5% (95% CI = 24.9-38.1%). Multivariate logistic regression analyses revealed that the diagnosis of bipolar disorder (OR = 2.18, 95% CI = 1.07-4.40), smoking (OR = 2.64, 95% CI = 1.10-6.37), anxiety symptoms (OR = 1.05, 95% CI = 1.02-1.08), and childhood maltreatment (OR = 1.04, 95% CI = 1.01-1.07) were potential associated factors of SA. In addition, anxiety symptoms had a mediating effect on the relationship between childhood maltreatment and SA. Conclusion: Adolescents and young adults with first depressive episodes and having experiences of childhood maltreatment are at a high risk of suicide. The severity of anxiety symptoms may mediate the relation between childhood maltreatment and suicide attempts in this group of patients.

Association of Tobacco Use and Exposure to Secondhand Smoke With Suicide Attempts Among Adolescents: Findings From 33 Countries

INTRODUCTION

There is evidence to suggest that tobacco use is associated with suicide attempts. However, it is unclear whether such an association can be extended to include secondhand smoke exposure. Using nationally representative data of school-attending adolescents from 33 countries, we examined the association of tobacco use and exposure to secondhand smoke with suicide attempts.

METHODS

We used data from the Global School-based Student Health Survey, a cross-sectional survey conducted among adolescents 12-15 years of age. We used logistic regression to estimate the country-specific associations. We then conducted random effect meta-analyses to obtain overall and country-income level pooled estimates. Lastly, we used logistic regression analyses to investigate a dose-response association of cigarette smoking and exposure to secondhand smoke with suicide attempts.

RESULTS

A positive association between tobacco use and suicide attempts among adolescents was present regardless of country-income level (low income: odds ratio 4.98, 95% CI: 3.11-7.96; lower middle income: 3.47, 2.91-4.15; upper middle income: 3.09, 2.75-3.47; and high income: 3.18, 2.63-3.84) and gender (boys: 3.28, 2.86-3.76; girls: 3.86, 3.30-4.51). Exposure to secondhand smoke was associated with suicide attempts, albeit weakly, among girls only (1.26, 1.14-1.39; boys: 1.00, 0.87-1.15). There was some evidence that a dose-response association of cigarette smoking and exposure to secondhand smoke with suicide attempts may only exist among girls.

CONCLUSIONS

Adolescents who use tobacco, and adolescent girls exposed to secondhand smoke were found to be more likely to attempt suicide; however, future longitudinal studies are warranted to assess causality.

IMPLICATIONS

Our findings indicate that routine screening of adolescents for tobacco use should be implemented globally, especially when assessing suicidal behaviors and risk. Future longitudinal and intervention studies are warranted to assess causality and whether prevention efforts such as tobacco control interventions and programmes targeting tobacco use and exposure to secondhand smoke among adolescents could ultimately lead to a reduction in the occurrence of suicide attempts.

The Involvement of Hypothalamus-Pituitary-Adrenal (HPA) Axis in Suicide Risk

Stress and Hypothalamic–Pituitary–Adrenal (HPA) axis dysregulation play a major role in various pathophysiological processes associated with both mood disorders and suicidal behavior. We conducted a systematic review with the primary aim of clarifying the nature and extent of HPA axis activity and suicidal behavior. The second aim of this review was to investigate whether potential biomarkers related to HPA axis abnormalities act as individual susceptibility factors for suicide. The PRISMA statement for reporting systematic reviews was used. Only articles published in English peer-reviewed journals were considered for possible inclusion; we excluded case reports, meta-analyses, and systematic reviews, and studies that did not clearly report statistical analysis, diagnostic criteria, or the number of patients included. Overall, 36 articles on HPA axis and suicide risk met inclusion criteria and were reviewed. Studies that investigated tests detecting biomarkers and the role of early life stressors in suicide risk were also included. We found that HPA axis activity is involved in suicide risk, regardless of the presence or absence of psychiatric conditions. The HPA axis abnormalities, mainly characterized by hyperactivity of the HPA axis, may exert an important modulatory influence on suicide risk. Impaired stress response mechanisms contribute to suicide risk. Targeting HPA axis dysregulation might represent a fruitful strategy for identifying new treatment targets and improving suicide risk prediction.

Leptin, Anxiety Symptoms, and Hypothalamic-Pituitary-Adrenal Axis Activity among Drug-Free, Female Suicide Attempters

BACKGROUND

Dysregulation of leptin secretion and functioning of the hypothalamic-pituitary-adrenal (HPA) axis may be involved in the pathophysiology of suicide. Preclinical and clinical studies have shown interactions between the HPA axis and leptin. There is also evidence for a negative relationship between leptin and anxiety in humans. However, these possible associations have not been studied in individuals with attempted suicide.

OBJECTIVES

To examine the relationship between leptin, HPA axis activity, and anxiety in individuals with a recent suicide attempt.

METHOD

Sixty-nine individuals with a recent suicide attempt (n = 37 females; n = 32 males) were recruited and subjected to the Dexamethasone Suppression Test (DST), lumbar puncture, and evaluation with the Comprehensive Psychopathological Rating Scale from which the Brief Scale for Anxiety (BSA) was derived. Leptin was analyzed in cerebrospinal fluid (CSF) and cortisol in serum. Leptin was corrected for body mass index (BMI) by dividing CSF-leptin by BMI (CSF-leptin/BMI). Due to gender-related differences in leptin secretion and HPA axis activity, calculations were made for males and females separately.

RESULTS

Significant differences were only found among females; CSF-leptin/BMI levels correlated significantly and negatively with BSA (p < 0.05), pre-DST cortisol, and post-DST serum cortisol at 8 a.m. and 3 p.m. (all p < 0.05). Furthermore, CSF-leptin/BMI was significantly lower in nonsuppressors of dexamethasone as compared to suppressors (p < 0.05).

CONCLUSIONS

These findings suggest that in females with a recent suicide attempt, low CSF leptin may be related to symptoms of anxiety and a hyperactive HPA axis.

Dexamethasone Suppression Test May Predict More Severe/Violent Suicidal Behavior

INTRODUCTION

Several studies demonstrated that the hypothalamic-pituitary-adrenal (HPA) axis is dysregulated in suicide attempters. Prospective studies found that people with an abnormal response at the dexamethasone suppression test (DST) are more likely to commit suicide. However, whether DST may predict suicide attempts remains less clear. A possible strategy to address this question is to consider the suicide attempt lethality.

OBJECTIVES

(1) To compare the pre- and post-DST cortisol levels in serious/violent suicide attempters and in non-serious/non-violent suicide attempters, and (2) to investigate whether cortisol level can predict new suicide attempts or their lethality.

METHODS

The study included 70 recent suicide attempters (25 with a serious or violent attempt) who were followed for two years. Three saliva samples for cortisol measurement were obtained at 8a.m., 3p.m., and 9p.m. before the DST (pre-DST). Then, at 11 p.m., 1 mg of dexamethasone was given orally. The following day (post-DST), three saliva samples were collected at the same hours as before. The post-DST-pre-DST salivary cortisol Δ index was calculated for each collection time. The Risk-Rescue Ratio Scale (RRRS) and the Suicidal Intent Scale (SIS) were used to characterize the suicide attempt at inclusion and those occurring during the follow-up.

RESULTS

Post-DST cortisol level at 9 p.m. was higher in patients with an initial violent or serious suicide attempt than in non-violent/non-serious attempters (p < .010). Higher post-DST cortisol at 9p.m. was associated with lower RRRS rescue score and higher clinical impression of suicide severity at inclusion. Among the 66 patients who completed the follow-up, 26 attempted suicide again at least once. Higher pre-DST cortisol at 8a.m. predicted new suicide attempts during the follow-up (OR = 2.15 [1.11, 4.15]), and higher cortisol Δ index at 9p.m. was associated with higher suicide intent during the follow-up.

CONCLUSIONS

Our results suggest that HPA axis hyper-reactivity monitored with the DST is a marker of violent/serious suicide attempt with lower rescue possibility. Furthermore, higher changes between pre-DST and post-DST cortisol levels may predict higher suicide intent. These findings might help to characterize the biological features of nearest suicide phenotypes.

Understanding suicide: Focusing on its mechanisms through a lithium lens

BACKGROUND

Current intervention strategies have been slow in reducing suicide rates, particularly in mood disorders. Thus, for intervention and prevention, a new approach is necessary. Investigating the effects of a medication known for its anti-suicidal properties on neurobiological and neurocognitive substrates of suicidal thinking may provide a deeper and more meaningful understanding of suicide.

METHOD

A literature search of recognised databases was conducted to examine the intersection of suicide, mood disorders, and the mechanisms of lithium.

RESULTS

This review synthesises the extant evidence of putative suicide biomarkers and endophenotypes and melds these with known actions of lithium to provide a comprehensive picture of processes underlying suicide. Specifically, the central importance of glycogen synthase kinase-3β (GSK3β) is discussed in detail because it modulates multiple systems that have been repeatedly implicated in suicide, and which lithium also exerts effects on.

LIMITATIONS

Suicide also occurs outside of mood disorders but we limited our discussion to mood because of our focus on lithium and extending our existing model of suicidal thinking and behaviour that is contextualised within mood disorders.

CONCLUSIONS

Focusing on the neurobiological mechanisms underpinning suicidal thinking and behaviours through a lithium lens identifies important targets for assessment and intervention. The use of objective measures is critical and using these within a framework that integrates findings from different perspectives and domains of research is likely to yield replicable and validated markers that can be employed both clinically and for further investigation of this complex phenomenon.

Impulsivity and Saliva Cortisol in Patients with Suicide Attempt and Controls

OBJECTIVES

The objective of this study was to prove concepts in the characterization of suicidal patients and the possible usefulness of those markers to potentially identify patients with a higher risk for suicidality.

METHODS

Patients with a recent suicide attempt were compared with patients suffering from depression, adjustment disorder, anxiety, or eating disorders without suicidality, healthy controls and remitted patients with a history of at least 1 suicide attempt (≥1 year). We analyzed impulsivity (Barratt Impulsivity Scale, BIS) and saliva cortisol concentrations.

RESULTS

Independently of suicidality and disease state patients display higher BIS scores than healthy controls. Saliva cortisol levels tend to be higher in patients in the acute disease state than in remitted patients and healthy controls.

CONCLUSIONS

Saliva cortisol may be a useful marker that reveals alterations in nonsuicidal patients suffering from depression, adjustment disorder, anxiety, or eating disorders who might be at risk.

The androgen model of suicide completion

Suicide is a devastating public health issue that imposes severe psychological, social, and economic burdens not only for the individuals but also for their relatives, friends, clinicians, and the general public. Among the different suicidal behaviors, suicide completion is the worst and the most relevant outcome. The knowledge of biological etiopathological mechanisms involved in suicide completion is limited. Hitherto, no objective markers, either alone or in combination, can reliably predict who will complete a suicide. However, such parameters are strongly needed to establish and optimize prediction and prevention. We introduce here a novel ideation-to-completion framework in suicide research and discuss the problems of studies aiming at identifying and validating clinically useful markers. The male gender is a specific risk factor for suicide, which suggests that androgen effects are implicated in the transition from suicidal ideation to suicide completion. We present multiple lines of direct and indirect evidence showing that both an increased prenatal androgen load (with subsequent permanent neuroadaptations) and increased adult androgen activity are involved in suicide completion. We also review data arguing that modifiable maternal behavioral traits during pregnancy contribute to the offspring's prenatal androgen load and increase the risk for suicide completion later in life. We conclude that in utero androgen exposure and adult androgen levels facilitate suicide completion in an synergistic manner. The androgen model of suicide completion provides the basis for the development of novel predictive and preventive strategies in the future.

Epigenetic Changes in the CRH Gene are Related to Severity of Suicide Attempt and a General Psychiatric Risk Score in Adolescents

The aim of this study, comprising 88 suicide attempters, was to identify hypothalamic-pituitary-adrenal (HPA) -axis coupled CpG-sites showing methylation shifts linked to severity of the suicide attempt. Candidate methylation loci were further investigated as risk loci for a general psychiatric risk score in two cohorts of adolescents (cohort 1 and 2). The genome-wide methylation pattern was measured in whole blood using the Illumina Infinium Methylation EPIC BeadChip. Subjects were stratified into high-risk and low-risk groups based on the severity of the suicidal behavior. We included CpG sites located within 2000 basepairs away from transcriptional start site of the following HPA-axis coupled genes: corticotropin releasing hormone (CRH), corticotropin releasing hormone binding protein (CRHBP), corticotropin releasing hormone receptor 1 (CRHR1), corticotropin releasing hormone receptor 2 (CRHR2), FK506-binding protein 51 (FKBP5) and the glucocorticoid receptor (NR3C1). The methylation state of two corticotropin releasing hormone (CRH)-associated CpG sites were significantly hypomethylated in the high-risk group of suicide attempters (n = 31) (cg19035496 and cg23409074) (p < 0.001). Adolescent cohort 1 and 2 consisted of 129 and 93 subjects, respectively, and were stratified by the in silico generated DAWBA measurements of a general psychiatric risk score into high-risk group (>~50% risk) or controls. In adolescent cohort 2, cg19035496 was hypermethylated in subjects with a high general psychiatric risk score. Our results show epigenetic changes in the CRH gene related to severity of suicide attempt in adults and a general psychiatric risk score in adolescents.

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Two CRH-associated CpG sites were significantly hypomethylated in the high-risk group of suicide attempters.

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In adolescent cohort, cg19035496 was hypermethylated in subjects with a high general psychiatric risk score.

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Epigenetic modulatory effects on the HPA axis dysregulation are associated with psychiatric illness and suicidal behavior.

In this study, comprising 88 suicide attempters, we aimed to identify epigenetic changes in stress system linked to severity of the suicide attempt. In the next step, we investigated if the same epigenetic changes could be detected in adolescents with high risk for psychiatric illness. The methylation pattern was measured in blood and subjects were stratified into high-risk and low-risk groups based on the severity of the suicidal behavior. One corticotropin releasing hormone (CRH)-a key regulator of stress system-associated CpG site showed less methylation in the high-risk group and was hypermethylated in adolescents with a high general psychiatric risk score. Epigenetic changes in the CRH gene were related to severity of suicide attempt in adults and a general psychiatric risk score in adolescents.

Predicting suicidal behaviours using clinical instruments: systematic review and meta-analysis of positive predictive values for risk scales

BackgroundPrediction of suicidal behaviour is an aspirational goal for clinicians and policy makers; with patients classified as 'high risk' to be preferentially allocated treatment. Clinical usefulness requires an adequate positive predictive value (PPV).AimsTo identify studies of predictive instruments and to calculate PPV estimates for suicidal behaviours.MethodA systematic review identified studies of predictive instruments. A series of meta-analyses produced pooled estimates of PPV for suicidal behaviours.ResultsFor all scales combined, the pooled PPVs were: suicide 5.5% (95% CI 3.9-7.9%), self-harm 26.3% (95% CI 21.8-31.3%) and self-harm plus suicide 35.9% (95% CI 25.8-47.4%). Subanalyses on self-harm found pooled PPVs of 16.1% (95% CI 11.3-22.3%) for high-quality studies, 32.5% (95% CI 26.1-39.6%) for hospital-treated self-harm and 26.8% (95% CI 19.5-35.6%) for psychiatric in-patients.ConclusionsNo 'high-risk' classification was clinically useful. Prevalence imposes a ceiling on PPV. Treatment should reduce exposure to modifiable risk factors and offer effective interventions for selected subpopulations and unselected clinical populations.

Animal models to improve our understanding and treatment of suicidal behavior

Worldwide, suicide is a leading cause of death. Although a sizable proportion of deaths by suicide may be preventable, it is well documented that despite major governmental and international investments in research, education and clinical practice suicide rates have not diminished and are even increasing among several at-risk populations. Although nonhuman animals do not engage in suicidal behavior amenable to translational studies, we argue that animal model systems are necessary to investigate candidate endophenotypes of suicidal behavior and the neurobiology underlying these endophenotypes. Animal models are similarly a critical resource to help delineate treatment targets and pharmacological means to improve our ability to manage the risk of suicide. In particular, certain pathophysiological pathways to suicidal behavior, including stress and hypothalamic-pituitary-adrenal axis dysfunction, neurotransmitter system abnormalities, endocrine and neuroimmune changes, aggression, impulsivity and decision-making deficits, as well as the role of critical interactions between genetic and epigenetic factors, development and environmental risk factors can be modeled in laboratory animals. We broadly describe human biological findings, as well as protective effects of medications such as lithium, clozapine, and ketamine associated with modifying risk of engaging in suicidal behavior that are readily translatable to animal models. Endophenotypes of suicidal behavior, studied in animal models, are further useful for moving observed associations with harmful environmental factors (for example, childhood adversity, mechanical trauma aeroallergens, pathogens, inflammation triggers) from association to causation, and developing preventative strategies. Further study in animals will contribute to a more informed, comprehensive, accelerated and ultimately impactful suicide research portfolio.

History of childhood trauma as risk factors to suicide risk in major depression

The aim of this study was to compare childhood trauma scores domains between Major Depressive Disorder (MDD) patients with and without suicide risk. This is cross-sectional study including a clinical sample of adults (18-60 years) diagnosed with MDD through the Mini International Neuropsychiatric Interview Plus version (MINI Plus). The Childhood Trauma Questionnaire (CTQ) was also used to verify types of trauma scores: abuse (emotional, physical, and sexual) and neglect (emotional and physical). Adjusted analysis was performed by linear regression. The sample was composed to 473 patients, suicide risk was observed in 16.3% of them. Suicide risk was independently associated with emotional abuse and neglect and sexual abuse, but not with physical abuse and neglect. Different domains of childhood trauma are associated with suicide risk in MDD population and emotional trauma should be considered a risk factor for suicide risk in MDD patients.

The Extrinsic Coagulation Pathway: a Biomarker for Suicidal Behavior in Major Depressive Disorder

Although an association between major depressive disorder (MDD) and suicide exists, most depressed patients never attempt suicide. An improved understanding of the factors contributing to suicidal risk in MDD can provide direction for suicide predictor development. In MDD suicide attempters (MDD-SA), MDD non-attempters (MDD-NA), and healthy controls (HC) (n = 12 each group), complementary plasma proteomics identified 45 differential proteins mapped to coagulation and inflammation, 25 of which underwent Western blotting. In another cohort including antidepressant-treated patients (n = 49 each group), seven additional extrinsic pathway proteins were selected for ELISA. Two inflammatory proteins and eight coagulatory proteins demonstrated alterations in MDD-SA relative to MDD-NA and HC. Applying a relative mass-action ratio, MDD-SA subjects displayed a higher relative prothrombinase activity than MDD-NA subjects, while healthy controls displayed higher relative prothrombinase activity than both MDD-SA and MDD-NA subjects. Consistent with our human findings, we found that heparin treatment significantly increased forced swimming test (FST) immobility time in rodents. MDD, independent of suicidality, is associated with a proinflammatory state accompanied by a hypothrombotic state. Suicidal behavior in MDD is associated with a more pronounced proinflammatory and prothrombotic phenotype accompanied by extrinsic pathway activation, revealing an extrinsic pathway biomarker that can be applied in predicting and monitoring suicidal risk.

The Expression of the Suicide-Associated Gene SKA2 Is Decreased in the Prefrontal Cortex of Suicide Victims but Not of Nonsuicidal Patients

BACKGROUND

Recent study of genome-wide DNA methylation profiling in the postmortem brain of suicidal and nonsuicidal subjects found that gene expression of spindle and kinetochore associated complex subunit 2 (SKA2) is decreased in the postmortem brain of suicide victims compared with nonsuicidal, nonpsychiatric control subjects.

METHODS

To determine if decreased SKA2 is specific to suicide and independent of diagnosis, we determined gene and protein expression of SKA2 in the prefrontal cortex obtained from suicide victims (n= 52), nonsuicidal psychiatric subjects (n= 27), and normal controls (n= 24). We determined gene expression by quantitative PCR technique and protein expression by Western blot. The postmortem brain samples were obtained from the Maryland Psychiatric Research Center.

RESULTS

We found that protein and gene expression of SKA2 was significantly reduced in the prefrontal cortex of suicide victims compared with normal control subjects and nonsuicidal patients. We also found that SKA2 protein and gene expression in depressed suicide victims, schizophrenic suicide victims, and suicide victims with substance abuse and/or conduct disorders was significantly decreased compared with normal control subjects and also with nonsuicidal depressed or schizophrenic subjects.

CONCLUSIONS

This study shows that decreased gene and protein expression of SKA2 observed in the prefrontal cortex of suicide victims is specific to suicide, which was not observed in the brain of nonsuicidal patients. It also indicates reduced SKA2 expression in suicide is independent of psychiatric diagnosis, since it is observed in all diagnostic groups studied. Therefore, SKA2 may be a potential biomarker for suicide.

Smoking and Suicide: A Meta-Analysis

BACKGROUND

Many studies have reported a positive association between smoking and suicide, but the results are inconsistent. This meta-analysis was carried out to estimate the association between smoking and suicidal ideation, suicide plan, suicide attempt, and suicide death.

METHODS

Major electronic databases including PubMed, Web of Science, Scopus, and ScienceDirect were searched until May 2015. The reference lists of included studies were screened too. Epidemiological studies addressing the association between smoking and suicidal behaviors were enrolled. The heterogeneity across studies was explored by Q-test and I2 statistic. The possibility of publication bias was assessed using Begg's and Egger's tests and Trim & Fill analysis. The results were reported based on risk ratio (RR) and odds ratio (OR) with 95% confidence intervals (CI) using a random-effects model.

RESULTS

We identified a total of 8062 references and included 63 studies with 8,063,634 participants. Compared to nonsmokers, the current smokers were at higher risk of suicidal ideation (OR = 2.05; 95% CI: 1.53, 2.58; 8 studies; I2 = 80.8%; P<0.001), suicide plan (OR = 2.36; 95% CI: 1.69, 3.02; 6 studies; I2 = 85.2%; P<0.001), suicide attempt (OR = 2.84; 95% CI: 1.49, 4.19; 5 studies; I2 = 89.6%; (P<0.001), and suicide death (RR = 1.83; 95% CI: 1.64, 2.02; 14 studies; I2 = 49.7%; P = 0.018).

CONCLUSIONS

There is sufficient evidence that smoking is associated with an increased risk of suicidal behaviors. Therefore, smoking is a contributing factor for suicide. Although this association does not imply causation, however, smoking prevention and cessation should be the target of suicide prevention programs.

Further evidence of low baseline cortisol levels in suicide attempters

BACKGROUND

Many, but not all studies of suicide attempters' cortisol response to stress-either social stress or pharmacological challenge-report an exaggerated response. Recent studies of resting baseline cortisol in past suicide attempters, however, have found lower baseline levels.

METHODS

In this study, baseline salivary cortisols were obtained prior to a stress procedure from adults with lifetime diagnoses of a mood disorder (N=69), 31.9% of whom had made a prior suicide attempt. Data were collected during the piloting of this stress procedure, at various times of day and with/without an additional confederate in the room.

RESULTS

Adjusting for procedural, demographic and clinical variables that affect salivary cortisol levels-including time of day of sampling, order of procedure with respect to other assessments, past alcohol abuse, current medication use, and bipolar diagnosis-past suicide attempters had lower baseline cortisol levels compared to non-attempters.

LIMITATIONS

This is a pilot study with modest sample sizes using statistical, rather than experimental control of numerous variables affecting salivary cortisol levels.

CONCLUSIONS

Results confirm previous studies. Low baseline cortisol levels have been associated with childhood adversity and externalizing disorders, suggesting a potential role in reducing inhibitions for risky and dangerous behaviors. Further research is needed to more fully characterize these associations and their role in suicidal behavior risk.

Plasma apolipoprotein E and severity of suicidal behaviour

There is evidence for association between low cholesterol levels and suicidal behaviour. Since apolipoprotein E (ApoE) is involved in the cholesterol metabolism in both the periphery and in the central nervous system; it may be of particular interest in the neurobiology of suicidal behaviour. Furthermore, hypothalamic-pituitary-adrenal (HPA) axis function, one of the main biological systems implicated in both suicidal behaviour and early-life adversity, affect ApoE levels. Very few studies have assessed plasma ApoE in relation to suicidal behaviour. The purpose of this study was to investigate levels of ApoE in plasma in relation to the severity of suicidal behaviour and life-time adversity in the form of exposure to interpersonal violence in suicide attempters. A total of 100 suicide attempters (67 women and 33 men) were enroled in the study. Information on earlier suicide attempts and age at onset of suicidal behaviour was gathered using the Karolinska Suicide History Interview. The Karolinska Interpersonal Violence Scale was used to assess exposure to interpersonal violence. Plasma ApoE was measured by immunonephelometry according to accredited routines. Patients with at least one earlier suicide attempt had significantly higher ApoE levels compared to suicide attempters debuting with suicidal behaviour at inclusion in the study. A higher number of earlier suicide attempts was significantly correlated with higher plasma ApoE levels. Age at onset was significantly negatively correlated with ApoE after adjusting for age. ApoE showed a significant positive correlation with exposure to interpersonal violence as a child in male suicide attempters. Our findings indicate that ApoE may be related to stress and trauma and the temporal severity of suicidal behaviour.

HPA axis dysregulation in men with hypersexual disorder

Hypersexual disorder integrating pathophysiological aspects such as sexual desire deregulation, sexual addiction, impulsivity and compulsivity was suggested as a diagnosis for the DSM-5. However, little is known about the neurobiology behind this disorder. A dysregulation of the hypothalamic pituitary adrenal (HPA) axis has been shown in psychiatric disorders but has not been investigated in hypersexual disorder. The aim of this study was to investigate the function of the HPA axis in hypersexual disorder. The study includes 67 male patients with hypersexual disorder and 39 healthy male volunteers. Basal morning plasma levels of cortisol and ACTH were assessed and low dose (0.5mg) dexamethasone suppression test was performed with cortisol and ACTH measured post dexamethasone administration. Non-suppression status was defined with DST-cortisol levels ≥ 138 nmol/l. The Sexual Compulsive scale (SCS), Hypersexual disorder current assessment scale (HD:CAS), Montgomery-Åsberg Depression Scale-self rating (MADRS-S) and Childhood trauma questionnaire (CTQ), were used for assessing hypersexual behavior, depression severity and early life adversity. Patients with hypersexual disorder were significantly more often DST non-suppressors and had significantly higher DST-ACTH levels compared to healthy volunteers. The patients reported significantly more childhood trauma and depression symptoms compared to healthy volunteers. CTQ scores showed a significant negative correlation with DST-ACTH whereas SCS and HD:CAS scores showed a negative correlation with baseline cortisol in patients. The diagnosis of hypersexual disorder was significantly associated DST non-suppression and higher plasma DST-ACTH even when adjusted for childhood trauma. The results suggest HPA axis dysregulation in male patients with hypersexual disorder.

Increased risk of suicide attempt in bipolar patients with severe tobacco dependence

BACKGROUND

The aim of our study was to investigate, in bipolar patients, the association between tobacco status (use and dependence) and history of suicide attempt, and to assess the possible role of inflammation as a missing link in the association between smoking status and history of suicide attempt.

METHODS

A total of 453 adult bipolar out-patients recruited in the French FondaMental Advanced Centres of Expertise for Bipolar Disorder were divided into two subgroups: 274 patients without past history of suicide attempt (non-SA), and 179 patients with a past history of suicide attempt (SA). Tobacco use and dependence, psychiatric and somatic comorbidities, history of childhood abuse, family history of suicide were assessed. Fasting blood tests yielded samples collected for the measurement of high sensitivity (hs-)CRP.

RESULTS

The risk of suicide attempt increased with smoking dependence. Notably, bipolar patients with a history of suicide attempt were three times more likely to have severe tobacco dependence, independently of confounding factors. However, we failed to find arguments promoting the hypothesis of inflammatory markers (through hs-CRP measure) in the link between tobacco dependence and suicidal behavior.

CONCLUSIONS

We found a significant association between severe tobacco dependence and history of suicide attempt, but not with level of CRP, independently of confusing factors. Longitudinal studies taken into account all these potential confusing factors are needed to confirm our results.

Biomarker identification in psychiatric disorders: from neuroscience to clinical practice

Patients with psychiatric disorders exhibit several neurobehavioral and neuropsychological alterations compared to healthy controls. However, signature endpoints of these behavioral manifestations have not yet been translated into clinical tests for diagnosis and follow-up measures. Recently, neuroproteomic approaches have been utilized to identify unique signature markers indicative of these disorders. Development of reliable biomarkers has the potential to revolutionize the diagnosis, classification, and monitoring of clinical responses in psychiatric diseases. However, the lack of biological gold standards, the evolving nosology of psychiatric disorders, and the complexity of the nervous system are among the major challenges that have hindered efforts to develop reliable biomarkers in the field of neuropsychiatry and drug abuse. While biomarkers currently have a limited role in the area of neuropsychiatry, several promising biomarkers have been proposed in conditions such as dementia, schizophrenia, depression, suicide, and addiction. One of the primary objectives of this review is to discuss the role of proteomics in the development of biomarkers specific to neuropsychiatry. We discuss and evaluate currently available biomarkers as well as those that are under research for clinical use in the future.

Toward a biosignature for suicide

OBJECTIVE

Suicide, a major cause of death worldwide, has distinct biological underpinnings. The authors review and synthesize the research literature on biomarkers of suicide, with the aim of using the findings of these studies to develop a coherent model for the biological diathesis for suicide.

METHOD

The authors examined studies covering a large range of neurobiological systems implicated in suicide. They provide succinct descriptions of each system to provide a context for interpreting the meaning of findings in suicide.

RESULTS

Several lines of evidence implicate dysregulation in stress response systems, especially the hypothalamic-pituitary-adrenal axis, as a diathesis for suicide. Additional findings related to neuroinflammatory indices, glutamatergic function, and neuronal plasticity at the cellular and circuitry level may reflect downstream effects of such dysregulation. Whether serotonergic abnormalities observed in individuals who have died by suicide are independent of stress response abnormalities is an unresolved question.

CONCLUSIONS

The most compelling biomarkers for suicide are linked to altered stress responses and their downstream effects, and to abnormalities in the serotonergic system. Studying these systems in parallel and in the same populations may elucidate the role of each and their interplay, possibly leading to identification of new treatment targets and biological predictors.

Relationship of hypothalamus-pituitary-adrenal (HPA) axis function and suicidal behavior in patients with depression

BACKGROUND

There have been few neuroendocrinology studies of suicidal behaviors among patients with depression and the results of these studies have been inconsistent.

AIM

To explore the association between the function of the hypothalamus-pituitary-adrenal (HPA) axis and suicidal behaviors in Chinese patients with depression.

METHODS

Several measures of HPA functioning in 14 depressed patients who had had suicidal behaviors in the two prior months ('depressed cases') were compared to those of 15 depressed inpatients who did not have prior suicidal behaviors ('depressed controls'): a dexamethasone suppression test (DST), the diurnal changes in serum cortisol levels during a single day before and after 6 weeks of treatment with paroxetine; and 24 h urinary 17-OH cortisol and free corticosterone before and after treatment. The Hamilton Depression Scale (HAMD) was used to measure the severity of depression. Daytime cortisol levels were also assessed in 15 non-depressed controls selected from individuals who had a routine health exam.

RESULTS

There were no statistically significant differences in the 24 h urinary measures of cortisol and corticosterone between depressed cases and depressed controls. In both groups the normal midnight drop in serum cortisol was nonsignificant prior to treatment but after treatment it became more pronounced. The DST was positive in more of the depressed cases than depressed controls (57% v. 20%, χ(2)=4.24, p=0.039). The correlation of cortisol serum levels with the HAMD total score and the item scores for hopelessness and suicidal ideation were statistically significant in the depressed case group both before and after treatment, but in the depressed control group these correlation coefficients did not reach statistical significance. The 08.00 h serum cortisol level in depressed cases was significantly greater than the level in non-depressed controls both before and after treatment, but the level in depressed controls was not significantly greater than that in non-depressed controls.

CONCLUSION

These findings are broadly consistent with those of prior studies about the relationship of depression and the functioning of the HPA axis. There were, however, some differences between depressed patients that did and did not report prior suicidal behavior which may indicate suicide-specific characteristics of HPA axis dysfunction. These differences merit further assessment in larger studies that distinguish patients who have made suicide attempts from those who only report prior suicidal ideation.

CSF 5-HIAA, cortisol and DHEAS levels in suicide attempters

The serotonin system and the hypothalamic-pituitary-adrenal (HPA) axis are involved in the biological vulnerability to suicidal behaviour. Altered levels of dehydroepiandrosterone (DHEA) and its sulphate ester DHEAS have been reported in neuropsychiatric conditions. The aim of this study was to investigate CSF levels of 5-Hydroxyindoleacetic acid (5-HIAA) and CSF and plasma levels of cortisol and DHEAS in 28 medication free suicide attempters and 19 healthy volunteers. Another aim was to investigate the relationship between neuroendocrine measures and childhood trauma in suicide attempters. As the study design includes a longitudinal part, we investigated whether CSF cortisol, 5-HIAA or DHEAS would predict subsequent suicide. We hypothesized higher cortisol levels in suicide attempters and lower CSF 5-HIAA levels and higher cortisol levels in suicide victims. Suicide attempters had higher CSF and plasma cortisol levels compared to healthy volunteers. Male suicide attempters had higher CSF DHEAS levels and female suicide attempters had lower CSF 5-HIAA levels compared to male and female healthy volunteers respectively. Exposure to interpersonal violence as a child showed a negative correlation with CSF cortisol/DHEAS ratio adjusted for age, gender and depression severity in a regression analysis. Suicide victims tended to have low CSF 5-HIAA and high CSF cortisol. Abused suicide victims had higher CSF cortisol compared to suicide victims with low exposure to interpersonal violence as a child. The results underlie the important role of the serotonergic system and HPA axis in suicidal behaviour and suggest that CSF DHEAS may be elevated in male suicide attempters.

Dysregulation of diurnal cortisol secretion affects abstinence induction during a lead-in period of a clinical trial for depressed cocaine-dependent patients

BACKGROUND AND OBJECTIVE

Hypothesizing that stress dysregulation may worsen cocaine dependence, we investigated the effect of diurnal cortisol secretion profile, suppression of cortisol secretion, and total cortisol secretion on retention, abstinence-based voucher earnings, days of cravings, and mood status of participants at the end of a 2-week medication-free lead-in prior to randomization in a clinical trial of mirtazapine (60 mg vs. placebo) for depressed cocaine-dependent patients.

METHODS

We measured saliva cortisol levels at 9 AM, 2 PM, and 5 PM on the first two consecutive days of a 2-week medication-free lead-in period. Results from saliva samples were used to estimate the total daily level of cortisol, the diurnal profile of secretion (typical vs. atypical), and response to dexamethasone suppression (.1 mg). Seventy-seven patients collected saliva samples at baseline, and 65 (85%) were suitable for profile analysis.

RESULTS

Patients with typical profiles (52%) collected significantly more abstinence-based voucher earnings during the lead-in (U = 299.50, p = .025). Diurnal secretion profile did not significantly affect mood status, days of craving, or retention. There were no significant effects of suppression of cortisol secretion or of total cortisol levels on any outcome measures.

CONCLUSION

In a subgroup of cocaine-dependent patients, deviation of cortisol secretion away from the homeostatic diurnal pattern was associated with reduced success at achieving early abstinence, an important determinant of treatment success.

Low vascular endothelial growth factor and interleukin-8 in cerebrospinal fluid of suicide attempters

A dysregulated immune system influencing pathways for cytokine regulation and growth factor expression is implicated in the pathophysiology of several neuropsychiatric disorders. Here, we analyzed cerebrospinal fluid (CSF) cytokines and growth factors with an ultra-sensitive immunoassay system in 43 medication-free suicide attempters and 20 healthy male volunteers. CSF vascular endothelial growth factor (VEGF) and CSF interleukin-8 (IL-8) levels were significantly lower in suicide attempters compared with healthy controls. Further, CSF VEGF showed a significant negative correlation with depression severity. CSF IL-6 levels did not differ between suicide attempters and healthy controls. Low CSF levels of VEGF may represent a lack of trophic support to neurons and downregulation of neurogenesis in the hippocampus reflecting more severe depressive states. IL-8 has also been reported as important in neuroprotection as well as having chemokine activity in the innate immune response. The results support a role for an impaired innate immunity and dysregulation of neuroprotection in the pathophysiology of depression and suicidal behavior.

Cigarette smoking and risk of completed suicide: a meta-analysis of prospective cohort studies

BACKGROUND

Epidemiologic studies have reported conflicting results relating smoking to suicide risk. We conducted a meta-analysis of prospective cohort studies to evaluate the association of cigarette smoking with completed suicide.

METHODS

Eligible prospective cohort studies were identified from PubMed and EMbase databases (from 1966 to May 2011) and the reference lists of retrieved articles. Two authors independently extracted data and assessed study quality using the Newcastle-Ottawa Scale. Study-specific risk estimates were pooled using random-effects model and generalized least squares trend estimation was used to assess dose-response relationship.

RESULTS

Fifteen prospective cohort studies involving 2395 cases among 1,369,807 participants were included in the meta-analysis. Our data suggested that cigarette smoking significantly increased the risk of completed suicide. Compared with never smokers, the pooled RR was 1.28 (95% CI: 1.001-1.641) for former smokers, and 1.81 (95% CI: 1.50-2.19) for current smokers, respectively. Subgroup analyses showed that the increased suicide risk among current smokers appeared to be consistent, although there was heterogeneity among studies of current smoking (p < 0.001). Significant dose-response relationship was found between smoking and suicide, and the risk of suicide was increased by 24% for each increment of 10 cigarettes smoked per day (RR, 1.24; 95% CI: 1.20-1.28).

CONCLUSIONS

Our meta-analysis robustly demonstrates that cigarette smoking is associated with an increased risk of completed suicide, consistent with a dose-response relationship. This conclusion has an important public health message for countries with high smoking prevalence and high suicide rate such as China.

Low plasma vascular endothelial growth factor (VEGF) associated with completed suicide

OBJECTIVES

Immunological differences have previously been associated with depression and suicidal behaviour. Several cytokines have been identified as potentially important in understanding the pathophysiology of mood disorders and suicidality. Here we aimed to identify new inflammatory biomarkers for suicide prediction.

METHODS

Plasma concentrations of interleukin (IL) 1-a , IL1-b, IL-2, IL-4, IL-6, IL-8, IL-10, interferon-gamma (IFNG), tumor necrosis factor-a (TNF-a), monocyte chemotactic protein-1 (MCP-1), epidermal growth factor (EGF), and vascular endothelial growth factor (VEGF) were measured in 58 suicide attempters with a high throughput automated biochip immunoassay system. Patients were evaluated using the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Suicide Intent Scale (SIS). All patients were followed up for cause of death.

RESULTS

We found significantly lower levels of VEGF in the seven patients who upon a mean follow-up of 13 years were found to have completed suicide. VEGF also showed a trend for negative correlation with the planning subscale of SIS. A trend could be shown for lower IL-2 and for higher IFNG levels in suicide victims.

CONCLUSIONS

Our study provides further support for a role of inflammation in the pathophysiology of suicidality. VEGF may be related with suicide risk.

Low CSF oxytocin reflects high intent in suicide attempters

Data from animal studies suggest that oxytocin is an important modulating neuropeptide in regulation of social interaction. One human study has reported a negative correlation between CSF oxytocin levels, life history of aggression and suicidal behaviour. We hypothesized that CSF oxytocin levels would be related to suicidal behaviour, suicide intent, lifetime interpersonal violence and suicide risk. 28 medication free suicide attempters and 19 healthy volunteers participated in this cross sectional and longitudinal study. CSF and plasma morning basal levels of oxytocin were assessed with specific radio-immunoassays. The Beck Suicide Intent Scale (SIS), the Freeman scale and the Karolinska Interpersonal Violence Scale (KIVS) were used to assess suicide intent and lifetime violent behaviour. All patients were followed up for cause of death. The mean follow-up was 21 years. Suicide attempters had lower CSF oxytocin levels compared to healthy volunteers p=0.077. In suicide attempters CSF oxytocin showed a significant negative correlation with the planning subscale of SIS. CSF oxytocin showed a significant negative correlation with suicide intent, the planning subscale of SIS and Freeman interruption probability in male suicide attempters. Correlations between plasma oxytocin levels and the planning subscale of SIS and Freeman interruption probability were significant in male suicide attempters. Lifetime violent behaviour showed a trend to negative correlation with CSF oxytocin. In the regression analysis suicide intent remained a significant predictor of CSF oxytocin corrected for age and gender whereas lifetime violent behaviour showed a trend to be a predictor of CSF oxytocin. Oxytocin levels did not differ significantly in suicide victims compared to survivors. CSF oxytocin may be an important modulator of suicide intent and interpersonal violence in suicide attempters.

Two HPA axis genes, CRHBP and FKBP5, interact with childhood trauma to increase the risk for suicidal behavior

Childhood trauma is associated with hypothalamic-pituitary-adrenal (HPA) axis dysregulation. Both factors increase risk for suicidal behavior. Corticotropin releasing hormone (CRH) regulates the HPA axis and its actions are moderated by a high-affinity binding protein (CRHBP). We hypothesized that CRHBP variation and interaction with childhood trauma might influence suicidal behavior. Moreover, there might be an additive effect with FKPB5, another HPA axis gene previously associated with suicidality in this dataset. African Americans were recruited: 398 treatment seeking patients with substance dependence (90% men; 120 suicide attempters) and 432 non-substance dependent individuals (40% men; 21 suicide attempters). A total of 474 participants (112 suicide attempters) completed the Childhood Trauma Questionnaire (CTQ). Haplotype-tagging SNPs were genotyped across CRHBP and, for completeness, across CRH, CRHR1 and CRHR2. FKBP5 genotypes were available. Three CRHBP SNPs rs6453267, rs7728378 and rs10474485 showed a nominally significant interaction with the continuous CTQ score to predict suicide attempt; rs7728378 remained significant after FDR correction. There was an additive effect with FKBP5: in the group exposed to high trauma, the prevalence of suicide attempt was 0.35-0.30 in carriers of either the FKBP5 rs3800373 major homozygote or the CRHBP rs7728378 major homozygote and 0.58 in carriers of both major homozygotes. Individuals without either major homozygote were resilient to the effects of childhood trauma (suicide attempt prevalence 0.24). Main effects of CRHBP rs6453267 and CRHR1 rs9900679, both unique to African ancestry, were detected. CRHBP variation may predispose, independently and additively, to suicidal behavior in individuals who have experienced childhood trauma.

CSF biomarkers in suicide attempters--a principal component analysis

OBJECTIVE

The objective of the present study was to identify biological patterns (factors) among 20 cerebrospinal fluid (CSF) biomarkers in suicide attempters and subsequently analyse their association with suicidal behaviour.

METHOD

We measured kynurenic acid, orexin, homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA), 3-methoxy-4-hydroxyphenylglycol, chemokines, matrix metalloproteases and cytokines in the CSF of 124 drug-free suicide attempters. Patients were evaluated for suicidality and psychiatric symptoms using well-defined psychiatric rating scales and followed-up regarding future suicide. We used principal component analysis to identify factors among the biological substances.

RESULTS

Four factors were extracted from the 20 biomarkers, explaining 52.4% of the total variance. Factors 1 and 2 were characterized by high loadings of chemokines and cytokines respectively. They were both associated with severe depressive symptoms. Factor 2 was also associated with a high suicidal intent. Factor 4 was characterized by strong loadings of the monoamine metabolites 5-HIAA and HVA, as well as orexin and interleukin-6. High scores on this factor were found in patients who performed a violent suicide attempt and in patients who subsequently completed suicide.

CONCLUSION

Our results suggest that specific combinations of CSF biomarkers may discriminate between types of suicidal behaviour and indicate increased risk for future suicide.

Potential peripheral biological predictors of suicidal behavior in major depressive disorder

Previous studies have shown that dysfunctions in the serotonin system and hypothalamic-pituitary-adrenal axis (HPA) are associated strongly with suicidal behavior and suicide, especially among individuals with major depressive disorder. Suicidal behavior has been explained using both the stress-diathesis model and the state-trait interaction model. Specifically, diatheses, or trait-dependent risk factors, are associated with dysfunctions in the serotonin system; however, stress responses, or state-dependent factors, are associated with HPA hyperactivity. Decreases in cholesterol and brain-derived neurotrophic factor (BDNF) levels have been associated with impaired brain plasticity among individuals with suicidal behavior. Decreased serotonin functioning has been measured using cerebral spinal fluid (CSF) 5-HIAA, fenfluramine challenge studies, and platelet 5-HT2A receptors. HPA axis dysfunction has been evaluated with the dexamethasone suppression test. Cholesterol and BDNF levels have been measured in blood serum or plasma. Nevertheless, challenges to finding promising and accessible neurobiological predictors of suicide and suicidal behavior remain. As suicide behavior is a complex phenomenon, a combined or multidimensional approach, including each of the aforementioned methods, may be required to predict suicide risk among individuals with major depressive disorder.

Decreased aldosterone in the plasma of suicide attempters with major depressive disorder

Hormones and neurobiological factors may be regulated differently in suicidal versus non-suicidal depressive patients. There is currently limited knowledge about the relation of substances in the Renin-Angiotensin-Aldosterone system to depression and suicidality. We therefore investigated whether plasma levels of renin and aldosterone differ between suicide attempters, non-suicidal depressive patients and healthy controls. Furthermore, we analyzed the relation of renin and aldosterone to psychiatric symptoms in the patients. Suicidal patients with MDD, adjustment disorder and dysthymia, as well as two control groups consisting of non-suicidal MDD patients and healthy subjects, were rated using the Comprehensive Psychopathological Rating Scale (CPRS), including the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Brief Scale for Anxiety (BSA). Plasma samples were frozen immediately after collection and stored at -80°C for 5-18years. Aldosterone and renin levels were analyzed using radioactive- and chemiluminescent immunoassays. We found that suicide attempters with MDD had significantly lower plasma levels of aldosterone than the other patient groups, as well as than the healthy controls. Moreover, increasing severity of psychiatric symptoms was associated with lower aldosterone levels in the suicide attempters with MDD. Non-suicidal patients with MDD did not differ significantly compared to healthy controls with respect to aldosterone and renin levels. These findings may indicate that low aldosterone levels could be a marker of suicidality in patients with MDD.

Association of FKBP5 gene haplotypes with completed suicide in the Japanese population

BACKGROUND

The hypothalamus-pituitary-adrenal (HPA) axis is known to have a role in suicidal behaviors in patients with affective disorders. However, the incomplete overlapping of the genetic factors of suicidal behaviors and the genetic factors of affective disorders suggest that the genes associated with predisposition to suicidal behaviors and affective disorders are different. There is increasing evidence that genes regulating the HPA axis have effects on suicidal behaviors. To test this idea, we examined the association of three HPA axis-related genes (glucocorticoid receptor (NR3C1), mineralocorticoid receptors (NR3C2), and FK506 binding protein 5 (FKBP5)) with suicide.

METHODS

We selected 3 SNPs of the FKBP5 (rs3800373, rs1360780, and rs2395635), 2 SNPs of the NR3C1 (rs6196 and rs10052957), and 3 SNPs of the NR3C2 genes (rs5525, rs5522, and rs2070951) based on their frequency in the Japanese population. Using TaqMan probe assays, we determined these SNPs in 219 completed suicide victims and 228 age- and gender-matched healthy control subjects.

RESULTS

No significant differences in genotypic distribution or allelic frequency of any single SNPs between the completed suicide and control groups were observed. The distributions of TT, TC, and GT haplotypes of the FKBP5 gene (comprised of rs3800373 and rs1360780) between the completed suicide and control groups were significantly different (p<0.05 for each haplotype). The TC haplotype withstood correction for multiple comparisons (corrected p = 0.034).

CONCLUSION

Our results suggest that haplotypes in FKBP5 gene are associated with completed suicide. This finding needs to be confirmed using rigorous SNPs selection in a larger sample.

The hypothalamic-pituitary-adrenal axis and serotonin abnormalities: a selective overview for the implications of suicide prevention

Suicidal behavior and mood disorders are one of the world's largest public health problems. The biological vulnerability for these problems includes genetic factors involved in the regulation of the serotonergic system and stress system. The hypothalamic-pituitary-adrenal (HPA) axis is a neuroendocrine system that regulates the body's response to stress and has complex interactions with brain serotonergic, noradrenergic and dopaminergic systems. Corticotropin-releasing hormone and vasopressin act synergistically to stimulate the secretion of ACTH that stimulates the biosynthesis of corticosteroids such as cortisol from cholesterol. Cortisol is a major stress hormone and has effects on many tissues, including on mineralocorticoid receptors and glucocorticoid receptors in the brain. Glucocorticoids produce behavioral changes, and one important target of glucocorticoids is the hypothalamus, which is a major controlling center of the HPA axis. Stress plays a major role in the various pathophysiological processes associated with mood disorders and suicidal behavior. Serotonergic dysfunction is a well-established substrate for mood disorders and suicidal behavior. Corticosteroids may play an important role in the relationship between stress, mood changes and perhaps suicidal behavior by interacting with 5-HT1A receptors. Abnormalities in the HPA axis in response to increased levels of stress are found to be associated with a dysregulation in the serotonergic system, both in subjects with mood disorders and those who engage in suicidal behavior. HPA over-activity may be a good predictor of mood disorders and perhaps suicidal behavior via abnormalities in the serotonergic system.

A randomised controlled study of risperidone and olanzapine for schizophrenic patients with neuroleptic-induced acute dystonia or parkinsonism

The objective of this study was to compare the effects of risperidone and olanzapine in schizophrenic patients with intolerant extrapyramidal side effects (EPS) on first generation antipsychotics. We conducted an 8-week, rater-blinded, flexible dose study. Seventy patients with schizophrenia, who met the DSM-IV research criteria of having neuroleptic-induced acute dystonia or parkinsonism, were randomly assigned to risperidone or olanzapine group. The primary outcome was a comparison of the incidence of concomitant anticholinergic drugs usage between the groups to manage their acute dystonia and parkinsonism. The average doses of risperidone and olanzapine from baseline to study end point were 1.8-3.5 mg/day and 7.7-11.7 mg/day, respectively. There were no significant differences in demographic data, severity of EPS or psychotic symptoms between the groups at baseline assessment. Patients taking risperidone had significantly higher incidence of using anticholinergic drugs to manage acute dystonia or parkinsonism overall during the study (OR = 5.17, 95%CI = 1.49-17.88, P = 0.013). There was no significant between-group difference in the changing of rating scales of EPS and psychotic symptoms. The results of our study favour olanzapine as a better choice in schizophrenic patients with intolerant EPS. Double-blinded, fixed dose and different ethnical study for EPS-intolerant schizophrenic patients is needed to confirm the results of our study.

A systematic review of hypothalamic-pituitary-adrenal axis function in schizophrenia: implications for mortality

There is convincing evidence that environmental stress plays a significant role in modifying both mental and physical health. The biological mechanisms linking stress to ill health are not fully understood, but significant evidence points to a central role of the stress axes; the hypothalamic- pituitary-adrenal (HPA) axis and the sympathetic nervous system. Together these two systems link the brain and the body and are crucial in maintaining homeostasis as well as improving an organism's survival chances in the face of environmental challenge. There is evidence of altered HPA axis function in people with a range of mental disorders, and this may in part explain the poor physical health of people with psychotic, mood and anxiety disorders. This paper systematically reviews HPA axis function in people with schizophrenia and relates this to the pattern of physical health seen in this disease. In summary, the evidence suggests people with schizophrenia can experience both hyper- and hypo-function of the HPA axis. It is likely that this contributes to the pattern of poor physical health and premature mortality suffered by people with schizophrenia, in particular the high rates of cardiovascular and metabolic disturbance.