The influence of inflammatory cytokines in physiopathology of suicidal behavior

Evaluation of peripheral inflammatory parameters of cases with suicide attempts

PURPOSE

The purpose of the present study was to examine the inflammation markers of patients who have attempted suicide by comparing them with those of healthy controls. The leukocyte cell levels, Neutrophil/Lymphocyte Ratios (NLR), Basophil/Lymphocyte Ratios (BLR), Platelet/Lymphocyte Ratios (PLR), Monocyte/Lymphocyte Ratios (MLR), Systemic Inflammation Index (SII), Neutrophil/Albumin Ratios (NAR) values were compared with those of healthy controls.

METHOD

A total of 376 people were included in the study (276 patients who attempted suicide, and 100 healthy people (the control group)). The demographic data and laboratory parameters of the participants were analyzed from the hospital automation system.

RESULTS

The participants' female/male ratio was 158/118 (42.8%/57.1%) in the group of patients who attempted suicide and 41/59 (41/59%) in the control group. When the distribution of laboratory parameters was evaluated, although the NLR, BLR, NAR, SII, and MLR values, which are indicators of peripheral inflammation, were high in patients who attempted suicide (p = 0.049 for MLR, p = 0.000 for other values), the PLR (p = 0.586) value did not differ significantly between the groups. Patients who had attempted more than one suicide had elevated BLR (p = 0.007), SII (p = 0.003), and NAR (p = 0.003) values.

DISCUSSION

Based on the results obtained, it was considered that paying attention to inflammation parameters in patient follow-ups, and monitoring of SII, NLR, BLR, and NAR values of patients who had attempted suicide once would be beneficial in preventing future suicide attempts. These results strengthen the idea that inflammatory processes play roles in the pathophysiology of suicidal behavior. However, further studies are needed to elucidate the complex pathophysiological mechanisms of immune pathways underlying suicidal behavior.

Proinflammatory cytokine levels, cognitive function, and suicidal symptoms of adolescents and young adults with major depressive disorder

Whether proinflammatory cytokine dysregulation and cognitive dysfunction are associated with suicidal symptoms in adolescents and young adults with major depressive disorder (MDD) remains uncertain. We assessed the cognitive function and proinflammatory cytokine levels of 43 and 51 patients aged 15-29 years with MDD and severe and mild suicidal symptoms, respectively, as well as those of 85 age- and sex-matched healthy controls. Specifically, we measured serum levels of C-reactive protein, tumor necrosis factor-α (TNF-α), interleukin-2, and interleukin-6 and assessed cognitive function by using working memory and go/no-go tasks. The severity of the patients' suicidal symptoms was based on Item 10 of the Montgomery-Åsberg Depression Rating Scale; scores of ≤ 2 and ≥ 4 indicated mild and severe symptoms, respectively. The patients with MDD and severe suicidal symptoms had higher levels of C-reactive protein (p = .019) and TNF-α (p = .002) than did the patients with mild symptoms or the healthy controls. The number of errors committed on the go/no-go by patients with MDD and severe suicidal symptoms (p = .001) was significantly higher than those by patients with MDD and mild symptoms or by controls. After adjusting for nonsuicidal depressive symptoms, we observed suicidal symptoms to be positively associated with TNF-α levels (p = .050) and errors on the go/no-go task (p = .021). Compared with mild suicidal symptoms, severe symptoms are associated with greater serum levels of proinflammatory cytokines and inferior cognitive function in adolescents and young adults with MDD.

Depicting the molecular features of suicidal behavior: a review from an "omics" perspective

Background Suicide is one of the leading global causes of death. Behavior patterns from suicide ideation to completion are complex, involving multiple risk factors. Advances in technologies and large-scale bioinformatic tools are changing how we approach biomedical problems. The "omics" field may provide new knowledge about suicidal behavior to improve identification of relevant biological pathways associated with suicidal behavior. Methods We reviewed transcriptomic, proteomic, and metabolomic studies conducted in blood and post-mortem brains from individuals who experienced suicide or suicidal behavior. Omics data were combined using systems biology in silico, aiming at identifying major biological mechanisms and key molecules associated with suicide. Results Post-mortem samples of suicide completers indicate major dysregulations in pathways associated with glial cells (astrocytes and microglia), neurotransmission (GABAergic and glutamatergic systems), neuroplasticity and cell survivor, immune responses and energy homeostasis. In the periphery, studies found alterations in molecules involved in immune responses, polyamines, lipid transport, energy homeostasis, and amino and nucleic acid metabolism. Limitations We included only exploratory, non-hypothesis-driven studies; most studies only included one brain region and whole tissue analysis, and focused on suicide completers who were white males with almost none confounding factors. Conclusions We can highlight the importance of synaptic function, especially the balance between the inhibitory and excitatory synapses, and mechanisms associated with neuroplasticity, common pathways associated with psychiatric disorders. However, some of the pathways highlighted in this review, such as transcriptional factors associated with RNA splicing, formation of cortical connections, and gliogenesis, point to mechanisms that still need to be explored.

Association between dementia risk and ulcerative colitis, with and without colectomy: a Swedish population-based register study

OBJECTIVE

This study aims to investigate the association of ulcerative colitis (UC) with all-cause dementia and assess differences in those with and without a total colectomy.

DESIGN, SETTING AND PARTICIPANTS

This Swedish prospective register-based study comprised 4.8 million individuals aged at least 59 years between 1964 and 2018 with the linkage of several Swedish national registers.

PRIMARY AND SECONDARY OUTCOME MEASURES

Individuals with dementia were defined according to International Classification of Diseases diagnostic codes and Anatomical Therapeutic Classification codes for medication prescriptions. Fitting Cox hazards models, the risk of developing all-cause dementia in individuals with and without UC was estimated. Further, we compared the risk of all-cause dementia among those with and without a colectomy.

RESULTS

Among 4 821 488 individuals (52.6% females) followed for 84.1 million person-years between 1964 and 2018, the incidence rate of all-cause dementia was 63.90 (63.73-64.07) events per 10 000 person-years in individuals without UC, 94.80 (92.04-97.64) among those with UC, 95.01 (92.25-97.86) in those with UC but without colectomy and 63.42 (40.92-98.31) in those with UC and a colectomy. Adjusted Cox models showed an increased all-cause dementia risk in individuals with UC (HR 1.07, 95% CI 1.04 to 1.10). We found no differences between unexposed individuals and those with UC and a colectomy (HR 0.89, 95% CI 0.57 to 1.38).

CONCLUSION

The findings are consistent with previous evidence suggesting a slightly increased dementia risk among individuals with UC. This study provided no evidence of further risk increase of dementia among those who had a colectomy.

Association of interleukin-6 with suicidal ideation in veterans: a longitudinal perspective

Introduction

Studies showing associations between inflammation in suicide are typically cross-sectional. Present study investigated how cytokine levels track with suicidal ideation and severity longitudinally.

Methods

Veterans with a diagnosis of major depressive disorder (MDD) with or without suicide attempt history (MDD/SA n = 38, MDD/NS n = 41) and non-psychiatric non-attempter controls (HC n = 33) were recruited, MDD/SA and HC groups were followed longitudinally at 3 months and 6 months. Blood plasma was collected and processed using Luminex Immunology Multiplex technology.

Results

Significant differences in depression severity (BDI) and suicidal ideation severity (SSI) were observed across all groups at study entry, wherein MDD/SA group had the highest scores followed by MDD/NS and HC, respectively. Cytokines IL-1β, IL-4, TNF-α, IFN-γ, and IL-6 were examined at study entry and longitudinally, with IL6 levels differing significantly across the groups (p = 0.0123) at study entry. Significant differences in changes in cytokine levels between depressed attempters and the control group were detected for IL-6 (interaction F1,91.77 = 5.58, p = 0.0203) and TNF-α (F1,101.73 = 4.69, p = 0.0327). However, only depressed attempters showed a significant change, in IL-6 and TNF-α levels, decreasing over time [IL-6: b = -0.04, 95% CI = (-0.08, -0.01), p = 0.0245 and TNF-α: b = -0.02, 95% CI = (-0.04, -0.01), p = 0.0196]. Although IL-6 levels were not predictive of suicidal ideation presence [OR = 1.34, 95% CI = (0.77, 2.33), p = 0.3067], IL-6 levels were significantly associated with suicidal ideation severity (b = 0.19, p = 0.0422).

Discussion

IL-6 was not associated with presence of suicidal ideation. IL-6 however, was associated with severity of ideation, suggesting that IL-6 may be useful in clinical practice, as an objective marker of heightened suicide risk.

Unlocking the Secrets: Exploring the Biochemical Correlates of Suicidal Thoughts and Behaviors in Adults with Autism Spectrum Conditions

Involving 1 million people a year, suicide represents one of the major topics of psychiatric research. Despite the focus in recent years on neurobiological underpinnings, understanding and predicting suicide remains a challenge. Many sociodemographical risk factors and prognostic markers have been proposed but they have poor predictive accuracy. Biomarkers can provide essential information acting as predictive indicators, providing proof of treatment response and proposing potential targets while offering more assurance than psychological measures. In this framework, the aim of this study is to open the way in this field and evaluate the correlation between blood levels of serotonin, brain derived neurotrophic factor, tryptophan and its metabolites, IL-6 and homocysteine levels and suicidality. Blood samples were taken from 24 adults with autism, their first-degree relatives, and 24 controls. Biochemical parameters were measured with enzyme-linked immunosorbent assays. Suicidality was measured through selected items of the MOODS-SR. Here we confirm the link between suicidality and autism and provide more evidence regarding the association of suicidality with increased homocysteine (0.278) and IL-6 (0.487) levels and decreased tryptophan (-0.132) and kynurenic acid (-0.253) ones. Our results suggest a possible transnosographic association between these biochemical parameters and increased suicide risk.

Risk for incident suicidality among psoriasis patients: a systematic review and meta-analysis

Previous meta-analyses have produced conflicting conclusions about suicidality risk among psoriasis patients. We aimed to update the evidence on the risk for the whole continuum of incident suicidality in psoriasis patients. We performed an update systematic review and meta-analysis and searched CENTRAL, PubMed, and Embase from January 1, 2017 to August 14, 2021 for relevant new cohort studies and incorporated new studies into our previous systematic review. Random-effects model meta-analysis was used to obtain pooled hazard ratio (HR) with 95% confidence interval (CI). Subgroup analysis was conducted according to age and disease severity. A total of 12 studies were included in this meta-analysis. We detected no significant differences in the risk for incident completed suicide (HR 1.33, 95% CI 0.91-1.95), suicide attempt (HR 1.22, 95% CI 0.96-1.56), suicidal behavior (HR 1.08, 95% CI 0.98-1.19), and suicide ideation (HR 1.74, 95% CI 0.99-3.06) between psoriasis patients and non-psoriatic controls. In the subgroup analysis based on age, an increased risk for incident suicide ideation was observed in pediatric subgroup (HR 1.50, 95% CI 1.12-2.03). The updated evidence suggests no increased risk for whole continuum of incident suicidality spectrum in psoriasis patients but an increased risk for incident suicide ideation among pediatric psoriasis patients. Involving mental health professionals may be crucial in psoriasis management especially in young patients.

Increased risk of suicidality in patients with psoriasis: A Nationwide cohort study in Korea

BACKGROUND

Psoriasis has a devastating psychological impact on patients' quality of life. However, the relationship between suicidality and psoriasis remains unclear.

OBJECTIVE

This study analysed and compared the risk of suicidality (suicidal ideation, suicide attempt and completed suicide) between patients with psoriasis and the general population.

METHODS

This nationwide, population-based, retrospective, cohort study analysed the Korean National Health Insurance Service claim data from 2005 to 2018.

RESULTS

The study included 348,439 patients with psoriasis aged over 18 years and with age- and sex-matched controls. The risk of suicidality was higher in the psoriasis group than in the control group [adjusted hazard ratio (aHR) 1.21; 95% confidence interval (CI), 1.18-1.24]. The aHR of suicidality was higher in the psoriatic arthritis group (aHR, 1.46; 95% CI, 1.39-1.54) than in the psoriasis-alone group (aHR, 1.17; 95% CI, 1.13-1.20). However, the severity of psoriasis and suicidality showed no correlation (mild psoriasis group: aHR, 1.22; 95% CI, 1.18-1.25; moderate-to-severe psoriasis group: aHR, 1.16; 95% CI, 1.10-1.23).

CONCLUSION

Patients with psoriasis have an increased risk of suicidality. In particular, the presence of arthritis in patients had a more significant effect on the risk of suicidality.

The role of microglia in neuropsychiatric disorders and suicide

This narrative review examines the possible role of microglial cells, first, in neuroinflammation and, second, in schizophrenia, depression, and suicide. Recent research on the interactions between microglia, astrocytes and neurons and their involvement in pathophysiological processes of neuropsychiatric disorders is presented. This review focuses on results from postmortem, positron emission tomography (PET) imaging studies, and animal models of schizophrenia and depression. Third, the effects of antipsychotic and antidepressant drug therapy, and of electroconvulsive therapy on microglial cells are explored and the upcoming development of therapeutic drugs targeting microglia is described. Finally, there is a discussion on the role of microglia in the evolutionary progression of human lineage. This view may contribute to a new understanding of neuropsychiatric disorders.

Relationship between the early repolarization pattern and a history of suicide attempts among drug-free psychiatric patients

Aim

Suicide attempts are an important severe psychiatric symptom and a clear outcome for mental disorders. Although the relationship between the early repolarization pattern in electrocardiogram and psychiatric disorders has recently been reported, these reports have not been able to exclude the influence of psychiatric drugs. This study aimed to investigate the relationship between the early repolarization pattern and a history of suicide attempts among patients not receiving psychiatric medication.

Methods

A total of 71 patients with a history of suicide attempts were investigated, 38 of whom were analyzed for this study. We compared the frequency of the early repolarization pattern between a suicide attempt group and a control group. Then, we investigated the association between the early repolarization pattern and the suicide attempt group by logistic regression analysis, including electrocardiographic findings associated with psychiatric disorders.

Results

The findings indicated that the frequency of the early repolarization pattern was significantly higher in the suicide attempt group (n = 20; 52.6%) than in the control group (n = 4; 10.5%) (P < 0.001), and the results of the logistic regression analysis indicated that the early repolarization pattern was associated with suicide attempts.

Conclusions

These findings suggest that the early repolarization pattern is associated with a history of suicide attempts.

Hyper/neuroinflammation in COVID-19 and suicide etiopathogenesis: Hypothesis for a nefarious collision?

Accumulating scientific and clinical evidence highlighted pathological hyperinflammation as a cardinal feature of SARS-CoV-2 infection and acute COVID-19 disease. With the emergence of long COVID-19 syndrome, several chronic health consequences, including neuropsychiatric sequelae, have gained attention from the public and medical communities. Since inflammatory mediators have also been accredited as putative biomarkers of suicidal ideations and behaviors, hyper- and neuroinflammation might share some colliding points, overlapping and being interconnected in the context of COVID-19. This review aims to provide a summary of current knowledge on the molecular and cellular mechanisms of COVID-19-associated hyper/neuroinflammation with focus on their relevance to the inflammatory hypothesis of suicide development. Subsequently, strategies to alleviate COVID-19 hyper/neuroinflammation by immunomodulatory agents (many of which at experimental stages) as well as psychopharmacologic/psychotherapeutic approaches are also mentioned. While suicide risk in COVID-19 survivors - until now little known - needs further analysis through longitudinal studies, current observations and mechanistic postulates warrant additional attention to this possibly emerging mental health concern.

Association of Atopic Dermatitis with Depression and Suicide: A Two-Sample Mendelian Randomization Study

Background

Atopic dermatitis (AD) has long been hypothesized to be associated with risk of depression and suicide, but the causal relationship between them is still unclear.

Objective

To evaluate the causality between AD, depression, and suicide using a Mendelian randomization (MR) approach.

Method

We extracted summary-level data for AD, major depression, and suicidal ideation or attempt from published, nonoverlapping genome-wide association studies (GWAS). Inverse variance-weighted (IVW) analysis was used as the primary analysis. Alternate methods, including weighted median, MR Egger, MR pleiotropy residual sum and outlier, weighted mode, and leave-out analysis, were performed to assess pleiotropy.

Results

13 SNPs (13,287 cases and 41,345 controls) were selected as instrumental variables (IVs). The IVW analysis indicated a statistically significant but small causal effect of AD on major depression (OR = 1.027, 95% CI 1.004-1.050; p = 0.020). No significant evidence was observed for a causal effect of AD on suicide. No significant effect of pleiotropy was found.

Conclusion

AD has a significant but small effect on major depression, but not on suicide.

Investigating Predictive Factors of Suicidal Re-attempts in Adolescents and Young Adults After a First Suicide Attempt, a Prospective Cohort Study. Study Protocol of the SURAYA Project

INTRODUCTION

Suicide is the fourth leading cause of death in youth. Previous suicide attempts are among the strongest predictors of future suicide re-attempt. However, the lack of data and understanding of suicidal re-attempt behaviors in this population makes suicide risk assessment complex and challenging in clinical practice. The primary objective of this study is to determine the rate of suicide re-attempts in youth admitted to the emergency department after a first suicide attempt. The secondary objectives are to explore the clinical, socio-demographic, and biological risk factors that may be associated with re-attempted suicide in adolescents and young adults.

METHODS

We have developed a single-center prospective and naturalistic study that will follow a cohort of 200 young people aged 16 to 25 years admitted for a first suicide attempt to the emergency department of Lyon, France. The primary outcome measure will be the incidence rate of new suicide attempts during 3 months of follow-up. Secondary outcomes to investigate predictors of suicide attempts will include several socio-demographic, clinical and biological assessments: blood and hair cortisol levels, plasma pro- and mature Brain-Derived Neurotrophic Factor (BDNF) isoforms proportion, previous infection with toxoplasma gondii, and C-Reactive Protein (CRP), orosomucoid, fibrinogen, interleukin (IL)-6 inflammatory markers.

DISCUSSION

To our knowledge, the present study is the first prospective study specifically designed to assess the risk of re-attempting suicide and to investigate the multidimensional predictive factors associated with re-attempting suicide in youth after a first suicide attempt. The results of this study will provide a unique opportunity to better understand whether youth are an at-risk group for suicide re-attempts, and will help us identify predictive factors of suicide re-attempt risk that could be translated into clinical settings to improve psychiatric care in this population.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, identifier: NCT03538197, first registered on 05/29/2018. The first patient was enrolled 05/22/2018.

Neutrophil/lymphocyte, platelet/lymphocyte and monocyte/lymphocyte ratios in mood disorders

Major depressive disorder (MDD) and bipolar disorders (BDs), the most severe types of mood disorders (MDs), are considered as among the most disabling illnesses worldwide. Several studies suggested that inflammatory neuroinflammation might be involved in the pathophysiology of MDs, while reporting increasing data on the relationships between these processes and classical neurotransmitters, hypothalamus-pituitary-adrenal axis (HPA), and neurotrophic factors. The assessment of neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) and monocyte/lymphocyte ratio (MLR) in peripheral blood represents a simple method to evaluate the inflammatory status. The aim of the present paper was to review the literature on the possible relationships between NLR, PLR and MLR in MDs, and to comment on their possible wider use in clinical research. Thirty-five studies were included in the present review. The majority of them higher values of these parameters, particularly NLR values, in patients with MDs, when compared to healthy subjects. The increase would appear more robust in patients with BD during a manic episode, thus indicating that it could be considered as both state and trait markers. In addition, increased NLR and PLR levels seem to represent prognostic elements for the early discovery of post-stroke depression. The findings of the present review would indicate the need to carry our further studies in this field. In particular, NLR, PLR and MLR seem to be promising tools to detect economically and easily the activation of the inflammatory system, and to perhaps evaluate the etiology and course of MDs. Again, they could suggest some information to better understand the relationship between inflammatory and cardiovascular disease and MDs, and thus, to provide clinical implications in terms of management and treatment.

Neutrophil-to-lymphocyte ratio and C-reactive protein in non-fatal suicidal attempts: A cross-sectional pilot study in Bangladesh

BACKGROUND

Precise identification of risk factors for suicide has been found as fundamentally challenging for the stakeholders. In search of that, the determination of potential biological markers of suicide has been scrutinizing in recent days. However, replicative studies across the culture and time are warranted to utilize the biomarkers in decision-making while considering suicide prevention.

OBJECTIVES

We aimed to measure the neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) in non-fatal suicidal attempts.

METHODS

This cross-sectional study was conducted from August 2020 to May 2021. Data were collected from 26 hospitalized patients after an immediate non-fatal suicidal attempt. We collected blood samples and assessed the complete blood count, NLR, and CRP. Data were analyzed by Statistical Package for the Social Science version 24.0 and Microsoft Excel software. We performed the independent Mann-Whitney U test to determine the variations between the groups. A value <.05 was considered as the level of significance.

RESULTS

The mean age of the study population was 24.1 (±7.3), more than half of them (n = 19, 73.1%) were female. The mode of attempt was either hanging (n = 13, 50.0%) or poisoning (n = 13, 50.0%). The previous attempt was noted in 12 (46.2%) cases. The mean CRP level was 16.8 (±30.2) mg/L and the mean NLR level was 8.3 (±6.8) for the total sample. Both the CRP and NLR were significantly higher among those who attempted hanging (P = .019 and .001).

CONCLUSIONS

The current study revealed preliminary findings on CRP and NLR among non-fatal suicides in Bangladesh where both of the parameters were significantly higher in non-fatal hanging.

Repurposing Ketamine in Depression and Related Disorders: Can This Enigmatic Drug Achieve Success?

Repurposing ketamine in the therapy of depression could well represent a breakthrough in understanding the etiology of depression. Ketamine was originally used as an anesthetic drug and later its use was extended to other therapeutic applications such as analgesia and the treatment of addiction. At the same time, the abuse of ketamine as a recreational drug has generated a concern for its psychotropic and potential long-term effects; nevertheless, its use as a fast acting antidepressant in treatment-resistant patients has boosted the interest in the mechanism of action both in psychiatry and in the wider area of neuroscience. This article provides a comprehensive overview of the actions of ketamine and intends to cover: (i) the evaluation of its clinical use in the treatment of depression and suicidal behavior; (ii) the potential use of ketamine in pediatrics; (iii) a description of its mechanism of action; (iv) the involvement of specific brain areas in producing antidepressant effects; (v) the potential interaction of ketamine with the hypothalamic-pituitary-adrenal axis; (vi) the effect of ketamine on neuronal transmission in the bed nucleus of stria terminalis and on its output; (vii) the evaluation of any gender-dependent effects of ketamine; (viii) the interaction of ketamine with the inflammatory processes involved in depression; (ix) the evaluation of the effects observed with single or repeated administration; (x) a description of any adverse or cognitive effects and its abuse potential. Finally, this review attempts to assess whether ketamine's use in depression can improve our knowledge of the etiopathology of depression and whether its therapeutic effect can be considered an actual cure for depression rather than a therapy merely aimed to control the symptoms of depression.

Periodontal Pathogens and Neuropsychiatric Health

Increasing evidence incriminates low-grade inflammation in cardiovascular, metabolic diseases, and neuropsychiatric clinical conditions, all important causes of morbidity and mortality. One of the upstream and modifiable precipitants and perpetrators of inflammation is chronic periodontitis, a polymicrobial infection with Porphyromonas gingivalis (P. gingivalis) playing a central role in the disease pathogenesis. We review the association between P. gingivalis and cardiovascular, metabolic, and neuropsychiatric illness, and the molecular mechanisms potentially implicated in immune upregulation as well as downregulation induced by the pathogen. In addition to inflammation, translocation of the pathogens to the coronary and peripheral arteries, including brain vasculature, and gut and liver vasculature has important pathophysiological consequences. Distant effects via translocation rely on virulence factors of P. gingivalis such as gingipains, on its synergistic interactions with other pathogens, and on its capability to manipulate the immune system via several mechanisms, including its capacity to induce production of immune-downregulating micro-RNAs. Possible targets for intervention and drug development to manage distal consequences of infection with P. gingivalis are also reviewed.

Affective temperament, depressive symptoms and interleukins in patients with psoriasis

INTRODUCTION

Psoriasis is a chronic inflammatory skin disease, in which psychological factors play an important role. In the studies of common markers of psoriasis and depression, the abnormal function of the stress axis in both diseases is highlighted, whereas interleukin-6 (IL-6) and interleukin-1 are indicated as particularly important.

AIM

To evaluate the relationship between the affective temperament traits and the intensity of depressive symptoms in patients with psoriasis in the context of immunoenzymatic markers.

MATERIAL AND METHODS

The study included 208 subjects. Severity of psoriasis was assessed by PASI. TEMPS-A was applied for the evaluation of affective temperament and BDI was used for the assessment of the intensity of depressive symptoms. The level of cytokines was determined by means of the immunoenzymatic method.

RESULTS

Patients presented a specific profile of affective temperament, with higher scores on depressive, anxious and irritable dimensions. The severity of depressive symptoms correlated positively with the severity of psoriasis. A significant correlation was found between IL-6 and the severity of psoriasis in patients with depressive disorders and psoriasis. No similar correlation was found in patients without depressive disorder.

CONCLUSIONS

Results of the present study show common mechanisms for psoriasis and depression. Specific traits of affective temperament may play an important role in the clinical picture of both diseases. Higher levels of IL-6 in patients with psoriasis predispose to more frequent occurrence of depressive disorders and the depressive dimension of affective temperament.

Severe Suicidality in Athletes with Chronic Traumatic Encephalopathy: A Case Series and Overview on Putative Ethiopathogenetic Mechanisms

Chronic traumatic encephalopathy (CTE) results from repetitive brain injuries and is a common neurotraumatic sequela in contact sports. CTE is often accompanied by neuropsychiatric symptoms, which could escalate to suicidal ideation (SI) and suicidal behaviour (SB). Nevertheless, fairly limited emphasis about the association between suicidality and CTE exists in medical literature. Here, we report two cases of retired professional athletes in high contact sports (boxing and ice hockey) who have developed similar clinical trajectories characterized by progressive neuropsychiatric symptoms compatible with a CTE diagnosis and subsequent SB in its severe forms (medical serious suicide attempt (SA) and completed suicide). In addition to the description of outlining clinical, neuropsychological, neuroimaging, and differential diagnosis elements related to these cases, we also hypothesized some mechanisms that might augment the suicide risk in CTE. They include those related to neurobiological (neuroanatomic/neuroinflammatory) dysfunctions as well as those pertaining to psychiatry and psychosocial maladaptation to neurotraumas and retirement from professional competitive activity. Findings described here can provide clinical pictures to improve the identification of patients with CTE and also potential mechanistic insights to refine the knowledge of eventual severe SB development, which might enable its earlier prevention.

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

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

Predictive inflammatory biomarkers for change in suicidal ideation in major depressive disorder and panic disorder: A 12-week follow-up study

Previous studies have investigated the role of inflammatory markers in suicidality of patients with major depressive disorder (MDD) or panic disorder (PD). However, few studies have investigated associations between serum inflammatory cytokine levels and suicidality. We hypothesized that MDD and PD status might be significantly associated with serum inflammatory cytokines and that we could predict levels of improvement in suicide ideation intensity using serum inflammatory biomarkers in patients with MDD and PD. For this study, 41 patients with MDD, 52 patients with PD, and 59 healthy control (HC) subjects were enrolled. Psychological measurements and serum inflammatory markers such as interleukin (IL) -6, -10, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and C reactive protein (CRP) were examined. A total of five visits were completed during 12 weeks. After controlling for confounding factors, log-transformed IL-6 (ln_IL-6) at baseline (MDD: 0.297 ± 0.626; PD: 0.342 ± 0.723; HC: -0.121 ± 0.858; p = 0.007, >0.0017, 0.05/30) and mean ln_IL-6 (MDD: 0.395 ± 0.550, PD: 0.249 ± 0.544, HC: -0.139 ± 0.622, p = 0.002, >0.0017, 0.05/30) levels were trends towards significantly higher in patients with MDD and PD than in HC. In MDD patients, a higher level of basal ln_TNF-α was a significant predictor of ΔSSI (changes in SSI scores between baseline and week 12) even after controlling for changes of depression symptoms and baseline SSI scores (standardized β = 0.541, p = 0.002 < 0.0028, 0.05/18). In conclusion, we could predict ΔSSI using baseline inflammatory biomarkers for patients with MDD.

Inflamed Mind: Multiple Genetic Variants of IL6 Influence Suicide Risk Phenotypes in Interaction With Early and Recent Adversities in a Linkage Disequilibrium-Based Clumping Analysis

Background: Understanding and predicting suicide remains a challenge, and a recent paradigm shift regarding the complex relationship between the immune system and the brain brought attention to the involvement of inflammation in neuropsychiatric conditions including suicide. Among cytokines, IL-6 has been most frequently implicated in suicide, yet only a few candidate gene studies and without considering the effect of stress investigated the role of IL6 in suicidal behaviour. Our study aimed to investigate the association of IL6 variation with a linkage disequilibrium-based clumping method in interaction with childhood adversities and recent stress on manifestations along the suicide spectrum. Methods: One thousand seven hundred and sixty-two participants provided information on previous suicide attempts, current suicidal ideation, thoughts of death, and hopelessness, and were genotyped for 186 variants in IL6. Early childhood adversities were recorded with an instrument adapted from the Childhood Trauma Questionnaire, recent life events were registered using the List of Threatening Life Events. Following a 3-step quality control, logistic and linear regression models were run to explore the effect of genotype and gene-environment interactions on suicide phenotypes. All regression models were followed by a clumping process based on empirical estimates of linkage disequilibrium between clumps of intercorrelated SNPs. Interaction effects of distinct types of recent life events were also analysed. Results: No clumps with significant main effects emerged, but we identified several clumps significantly interacting with childhood adversities on lifetime suicide attempts, current suicidal ideation, and current thoughts of death. We also identified clumps significantly interacting with recent negative life events on current suicidal ideation. We reported no clumps with significant effect on hopelessness either as a main effect or in interaction with childhood adversities or recent stress. Conclusion: We identified variant clumps in IL6 influencing suicidal behaviour, but only in interaction with childhood or recent adversities. Our results may bring us a step further in understanding the role of neuroinflammation and specifically of IL-6 in suicide, towards identifying novel biological markers of suicidal behaviour especially in those exposed to stressful experiences, and to fostering the adaptation of a new paradigm and identifying novel approaches and targets in the treatment of suicidal behaviour.

Suicidality in Patients with Brain Tumors: A Brief Literature Review with Clinical Exemplar

Background: Suicidality and brain tumors are two life-threatening conditions and, somewhat unexpectedly, the associations between them have scarcely been reported. Objective: In this study, we aimed to provide a brief literature review of epidemiological studies on suicidal ideation (SI) and suicidal behavior (SB) in patients with brain tumors. To illustrate various aspects of brain tumors that potentially underlie the emergence of suicidality, the review is supplemented with a clinical exemplar of a long-term survivor of brain tumor (glioblastoma) who experienced persistent SI. Furthermore, we discuss putative both neurobiological (including anatomical and immunological) and psychosocial mechanisms that might be accountable for the development of SI and SB in patients with brain tumors. Conclusions: While the etiology of this phenomenon appears to be multifactorial and still remains a subject of much debate, it is of critical importance to identify patients for which a psychiatric evaluation could recognize, in a timely manner, a possible suicide risk and alleviate the deep related suffering, by appropriate psychopharmacological and supportive and psychotherapeutic interventions.

An increase in IL-6 levels at 6-month follow-up visit is associated with SSRI-emergent suicidality in high-risk children and adolescents treated with fluoxetine

Major depressive disorder (MDD) is associated with alterations in circulatory cytokines, in adults as well as in children and adolescents. Administration of selective serotonin reuptake inhibitors (SSRIs) to MDD pediatric patients modifies cytokine levels. However, most studies only assessed changes over a short time period. In this study, we evaluated long-term effects of the SSRI fluoxetine (FLX) in children and adolescents treated for anxiety and/or MDD, including a high-risk group with pre-treatment suicidality. The study group included ninety-two patients (35 boys and 57 girls) with MDD and/or anxiety disorders, aged 13.90 ± 2.41 years. All patients were treated with FLX and followed for 6 months. The study group included children with pretreatment suicidality (high-risk group;N = 62) and without pretreatment suicidality (N = 30) according to the Columbia Suicide Severity Rating Scale. Plasma concentrations of TNFα, IL-6, and IL-1β were measured by enzyme linked immunosorbent assays before and after six months of treatment. IL-6 and IL-1β significantly increased as a factor of time after 6 months of treatment. The elevation was statistically significant confined to children with pretreatment suicidality. Within the children with pretreatment suicidality, IL-6 levels increased significantly after 6 months only in the children who developed SSRI-associated suicidality. To summarize, an increase in IL-6 levels after 6 months of treatment may be associated with SSRI-emergent suicidality in children with pretreatment suicidality. Further studies are needed to clarify the role and mechanism(s) of IL-6 in the pathogenesis of this life-threatening adverse event.

Inflammation and behavioral symptoms in preoperational glioma patients: Is depression, anxiety, and cognitive impairment related to markers of systemic inflammation?

PURPOSE

Behavioral symptoms, including depression, anxiety, and cognitive impairment, are common clinical symptoms of patients with glioma. However, the mechanisms underlying the behavioral symptoms of glioma patients remain unclear. In this study, we explore the correlation between markers of systemic inflammation and preoperational behavioral symptoms in glioma patients.

PATIENTS AND METHODS

Patients (n = 71) who had recently undertaken imaging (i.e., CT, MRI) for suspected glioma had a face-to-face interview, completed self-report scales, and provided blood samples. Furthermore, we tested blood samples by a protein chip to select differential inflammatory cytokines and further confirm such differences using liquid-phase chip technology.

RESULTS

The prevalence of depression, anxiety, and cognitive impairment in glioma patients prior to surgery in this study was 53.5%, 70.4%, and 32.4%, respectively. The increased levels of IFN-γ were positively correlated with clinical symptoms of depression in the glioma patients. Moreover, increased IL-2 levels were negatively associated with anxiety symptoms (p = .00) and positively correlated with cognitive impairment in glioma patients.

CONCLUSION

This study suggests that systemic inflammation is associated with behavioral symptoms in glioma patients. This provides further evidence of the contribution of inflammatory markers to psychological symptoms in the context of physical conditions and lays the foundation for the development of further treatments of the behavioral symptoms in glioma patients.

Increased circulatory IL-6 during 8-week fluoxetine treatment is a risk factor for suicidal behaviors in youth

OBJECTIVE

Selective serotonin reuptake inhibitors (SSRIs) are commonly used to treat anxiety and/or depression in pediatric populations. However, the response rates are low (approximately 50%). Moreover, SSRI use is frequently associated with adverse events (AE). Currently there are no available biomarkers for treatment response/AE. Identification of biomarkers predicting early response and/or AE could help maximize the benefit-risk ratio for the use of SSRIs, and accelerate matching of treatments to patients. Pro-inflammatory cytokines were proposed as potential biomarkers.

METHOD

Ninety-two patients (35 boys and 57 girls) with major depressive disorder and/or anxiety disorders, aged 13.90 ± 2.41 years, were treated with fluoxetine (FLX) for 8 weeks. Plasma concentrations of TNFα, IL-6, and IL-1β were measured by enzyme linked immunosorbent assays before and after FLX treatment. Clinical response and AE were measured using several clinical scales, including the Clinical Global Impression - improvement, Children's Depression Rating Scale-Revised, the Beck Depression Inventory, the Screen for Child Anxiety Related Emotional Disorders, the Columbia suicide severity rating scale, and the Suicide Ideation Questionnaire.

RESULTS

IL-6 levels increased after treatment only in the group of children who developed FLX-associated suicidality.

CONCLUSION

An increase in IL-6 levels during treatment may be a risk factor for the emergence of FLX-associated suicidality (OR = 1.70). Further studies are necessary to clarify the role and mechanism(s) of this cytokine in the pathogenesis of this life-threatening AE.

Risk for Suicidal Behavior Among Psoriasis Patients: A Nationwide Cohort Study

BACKGROUND

The link between psoriasis and suicidality remains elusive and understudied.

OBJECTIVE

The aim was to assess the risk of suicidal behavior in psoriasis patients.

METHODS

We used Taiwan's National Health Insurance Research Database to conduct a nationwide retrospective cohort study to examine the risk for suicidal behavior among psoriasis patients. We performed subgroup analyses based on the severity of psoriasis and psoriatic arthritis.

RESULTS

We included 169,909 psoriasis patients (including 13,959 with concomitant psoriatic arthritis and 155,950 with psoriasis alone) and 169,909 matched nonpsoriasis controls. Suicidal behavior occurred in 104 and 89 subjects in the psoriasis group and nonpsoriasis controls, respectively; we found no significantly increased risk for suicidal behavior among psoriasis patients when compared to nonpsoriasis controls [adjusted hazard ratio (HR) 1.17, 95% confidence interval (CI) 0.88‒1.55]. The subgroup analysis showed no significantly increased risk for suicidal behavior in both the severe psoriasis group (adjusted HR 0.92, 95% CI 0.51-1.64) and the mild psoriasis group (adjusted HR 1.26, 95% CI 0.91‒1.75) when compared to nonpsoriasis controls. Also, we found no significant increased risk for suicidal behavior in the group of psoriasis patients who also had psoriatic arthritis (adjusted HR 2.00, 95% CI 0.68‒5.85) and in the group of patients with psoriasis alone (adjusted HR 1.12, 95% CI 0.83‒1.50) when compared to nonpsoriasis controls.

CONCLUSION

In a Taiwanese setting, no link between psoriasis or psoriatic arthritis and suicidal behavior was detected.

Association of defecation disorders with suicidal ideation in young adult with chronic abdominal discomfort

BACKGROUND

The role of physical symptoms on suicidal ideation in adolescents is incompletely understood. The purpose of this study was to discover the potential physical symptoms predictors for suicidal ideation in college freshmen.

METHODS

This cross-sectional survey was conducted in a randomly selected freshmen population in Wuhan China (N = 2449). Questionnaire evaluated suicidal ideation as well as related psychosocial risks and gastrointestinal (GI) physical symptoms. The association between the suicidal ideation and potential predictors was analyzed by Mann-Whitney test and multiple logistic regression analysis.

RESULTS

A total of 2053 (83.8%) completed this survey and 64 (3.1%) was reported to have suicidal ideation. Anxiety (OR 5.44(2.40-12.35)), depression (OR 8.36(3.90-17.94)) and chronic abdominal discomfort (OR 2.06(1.07-3.94)) were independent predictors for suicidal ideation. In freshmen with chronic abdominal discomfort, interestingly, defecation disorder(P = 0.01) and low satisfaction of defecation (P = 0.04) was associated with high risk for suicidal ideation.

CONCLUSION

Defecation disorders were associated with high risk of suicidal intention in young adult with chronic abdominal discomfort. Our result implied that clinicians should be vigilant for suicidal ideation in chronic abdominal discomfort patients, especially those with defecation disorders.

The Role of BDNF in the Neuroimmune Axis Regulation of Mood Disorders

The neuroimmune system plays a crucial role in the regulation of mood disorders. Moreover, recent studies show that brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, is a key regulator in the neuroimmune axis. However, the potential mechanism of BDNF action in the neuroimmune axis' regulation of mood disorders remains unclear. Therefore, in this review, we focus on the recent progress of BDNF in influencing mood disorders, by participating in alterations of the neuroimmune axis. This may provide evidence for future studies in this field.

Infections, Anti-infective Agents, and Risk of Deliberate Self-harm and Suicide in a Young Cohort: A Nationwide Study

BACKGROUND

Evidence links infections to mental disorders and suicidal behavior. However, knowledge is sparse regarding less severe infections, anti-infective treatment, and deliberate self-harm. Using nationwide Danish longitudinal registers, we estimated associations between infections treated with anti-infective agents and infections requiring hospitalization with the risk of deliberate self-harm.

METHODS

A total of 1.3 million people born between 1977 and 2002 were followed during the period from 1995 to 2013. In total, 15,042 individuals were recorded with deliberate self-harm (92% had been treated with anti-infective agents and 19% had been hospitalized for infections) and 114 died by suicide (64% had been treated with anti-infective agents and 13% had been hospitalized for infections). Hazard rate ratios were obtained while adjusting for age, gender, calendar period, education, hospitalizations with infections, prescribed anti-infective agents during childhood, parental mental disorders, and parental deliberate self-harm.

RESULTS

Individuals with infections treated with anti-infective agents had an increased risk of deliberate self-harm with a hazard rate ratio of 1.80 (95% confidence interval = 1.68-1.91). The associations fitted a dose-response relationship (p < .001) and remained significant up to 5 years after last infection. An additive effect was found for individuals with an additional hospitalization for infections with an increased hazard rate ratio of 3.20 (95% confidence interval = 2.96-3.45) for deliberate self-harm.

CONCLUSIONS

An increased risk of deliberate self-harm was found among individuals with infections treated with anti-infective agents in temporal and dose-response associations. These results add to the growing literature on a possible link between infections and the pathophysiological mechanisms of suicidal behavior.

An inflammatory profile linked to increased suicide risk

BACKGROUND

Suicide risk assessments are often challenging for clinicians, and therefore, biological markers are warranted as guiding tools in these assessments. Suicidal patients display increased cytokine levels in peripheral blood, although the composite inflammatory profile in the subjects is still unknown. It is also not yet established whether certain inflammatory changes are specific to suicidal subjects. To address this, we measured 45 immunobiological factors in peripheral blood and identified the biological profiles associated with cross-diagnostic suicide risk and depression, respectively.

METHODS

Sixty-six women with mood and anxiety disorders underwent computerized adaptive testing for mental health, assessing depression and suicide risk. Weighted correlation network analysis was used to uncover system level associations between suicide risk, depression, and the immunobiological factors in plasma. Secondary regression models were used to establish the sensitivity of the results to potential confounders, including age, body mass index (BMI), treatment and symptoms of depression and anxiety.

RESULTS

The biological profile of patients assessed to be at increased suicide risk differed from that associated with depression. At the system level, a biological cluster containing increased levels of interleukin-6, lymphocytes, monocytes, white blood cell count and polymorphonuclear leukocyte count significantly impacted suicide risk, with the latter two inferring the strongest influence. The cytokine interleukin-8 was independently and negatively associated with increased suicide risk. The results remained after adjusting for confounders.

LIMITATIONS

This study is cross-sectional and not designed to prove causality.

DISCUSSION

A unique immunobiological profile was linked to increased suicide risk. The profile was different from that observed in patients with depressive symptoms, and indicates that granulocyte mediated biological mechanisms could be activated in patients at risk for suicide.

Interleukin-6 and Interleukin-10 in mood disorders: A population-based study

OBJECTIVE

The aim of this study was to assess if cytokines levels (IL-6 and IL-10) are related to major depressive disorder (MDD) and bipolar disorder (BD), in a population-based study.

METHODS

This was a cross-sectional study population-based, involving 1037 people aged 18-35. MDD, BD, anxiety and suicide risk were assessed using the Mini International Neuropsychiatric Interview. Serum IL-6 and IL-10 were measured by ELISA using a commercial kit.

RESULTS

The total sample comprised 1034 young adults, being 14.4% with MDD and 13.7% with BD. MDD and BD groups showed significantly higher serum IL-6 levels (p ≤ 0.001) and IL-10 levels (p ≤ 0.001) when compared to healthy control group. No correlation was found between serum IL-6 and IL-10 levels in health control group (p = 0.830; r = -0.008), non-suicide risk (p = 0.337; r = 0.032) and non-anxiety disorder (p = 0.375; r = 0.031). Covariance analysis showed that mood disorders alone, increase both interleukin levels (IL-6, p = 0.019; and IL-10, p = 0.026), whilst the interaction of mood disorders and suicide risk or anxiety disorders did not.

CONCLUSION

Our results suggest that inflammatory dysregulation may be involved in the physiopathology of mood disorders and serum IL-6 and IL-10 levels are putative biomarkers for these disorders.

Ethanol induces interferon expression in neurons via TRAIL: role of astrocyte-to-neuron signaling

RATIONALE

Alcohol use disorder (AUD) involves dysregulation of innate immune signaling in brain. Toll-like receptor 3 (TLR3), an innate immune receptor that is upregulated in post-mortem human alcoholics, leads to induction of interferon (IFN) signaling. IFNs have been linked to depressive-like symptoms and therefore may play a role in addiction pathology. Astrocyte-neuronal signaling may contribute to maladaptation of neuronal circuits.

OBJECTIVES

In this manuscript, we examine ethanol (EtOH) induction of IFN signaling in neuronal, astrocyte, and microglial cell lines and assess astrocyte-neuronal interactions.

METHODS

U373 astrocytes, SH-SY5Y neurons, and BV2 microglia were treated with EtOH and analyzed for autocrine/paracrine IFN signaling.

RESULTS

EtOH induced TLR3, IFNβ, and IFNγ in SH-SY5Y neurons and U373 astrocytes, but not in BV2 microglia. The IFN response gene TRAIL was also strongly upregulated by TLR3 agonist Poly(I:C) and EtOH in U373 astrocytes. TRAIL blockage via neutralizing antibody prevented induction of IFNs in SH-SY5Y neurons but not in U373 astrocytes. Blocking TRAIL in conditioned media from EtOH-treated astrocytes prevented induction of IFNs in SH-SY5Y neurons. Finally, an in vivo model of chronic 10-day binge EtOH exposure in C57BL6/J mice, as well as single acute treatment with Poly(I:C), showed increased TRAIL +IR cells in both orbitofrontal and entorhinal cortex.

CONCLUSIONS

This study establishes a role of astrocyte to neuron TRAIL release in EtOH-induced IFN responses. This may contribute to alcohol associated negative affect and suggest potential therapeutic benefit of TRAIL inhibition in AUD.

Risk of Suicidality in People with Psoriasis: A Systematic Review and Meta-Analysis of Cohort Studies

BACKGROUND

Psoriasis has been associated with psychiatric disorders such as depression and anxiety, but its relationship with suicidality (including suicide, suicide attempt, and suicidal ideation) is unclear.

OBJECTIVE

Our objective was to assess the risk of suicide, suicide attempt, suicidal ideation, and suicidality in people with psoriasis.

METHODS

We conducted a systematic review and meta-analysis of cohort studies examining the risk of suicide, suicide attempt, suicidal ideation, and suicidality in people with psoriasis. We searched the Cochrane Library, PubMed, and EMBASE from inception to 24 March 2017. Two authors independently selected studies, assessed the quality of included studies, and extracted data. Any disagreement was resolved by discussion with a third author.

RESULTS

Five population-based cohort studies were included and considered to be of high quality. We found no increase in the risk of suicide (risk ratio [RR] 1.13; 95% confidence interval [CI] 0.87-1.46), suicide attempt (RR 1.25; 95% CI 0.89-1.75), or suicidality (RR 1.26; 95% CI 0.97-1.64) among people with psoriasis. In the stratified analysis, we also found no increase in suicide, suicide attempt, and suicidality among people with either severe or mild psoriasis.

CONCLUSIONS

The available limited, very low-quality evidence does not support an association between psoriasis and suicidal thought and behavior. Further studies that provide data for different age and sex groups are needed to clarify whether a subgroup of patients with psoriasis has an elevated risk of suicidality.

Suicide and Lyme and associated diseases

PURPOSE

The aim of this paper is to investigate the association between suicide and Lyme and associated diseases (LAD). No journal article has previously performed a comprehensive assessment of this subject.

INTRODUCTION

Multiple case reports and other references demonstrate a causal association between suicidal risk and LAD. Suicide risk is greater in outdoor workers and veterans, both with greater LAD exposure. Multiple studies demonstrate many infections and the associated proinflammatory cytokines, inflammatory-mediated metabolic changes, and quinolinic acid and glutamate changes alter neural circuits which increase suicidality. A similar pathophysiology occurs in LAD.

METHOD

A retrospective chart review and epidemiological calculations were performed.

RESULTS

LAD contributed to suicidality, and sometimes homicidality, in individuals who were not suicidal before infection. A higher level of risk to self and others is associated with multiple symptoms developing after acquiring LAD, in particular, explosive anger, intrusive images, sudden mood swings, paranoia, dissociative episodes, hallucinations, disinhibition, panic disorder, rapid cycling bipolar, depersonalization, social anxiety disorder, substance abuse, hypervigilance, generalized anxiety disorder, genital-urinary symptoms, chronic pain, anhedonia, depression, low frustration tolerance, and posttraumatic stress disorder. Negative attitudes about LAD from family, friends, doctors, and the health care system may also contribute to suicide risk. By indirect calculations, it is estimated there are possibly over 1,200 LAD suicides in the US per year.

CONCLUSION

Suicidality seen in LAD contributes to causing a significant number of previously unexplained suicides and is associated with immune-mediated and metabolic changes resulting in psychiatric and other symptoms which are possibly intensified by negative attitudes about LAD from others. Some LAD suicides are associated with being overwhelmed by multiple debilitating symptoms, and others are impulsive, bizarre, and unpredictable. Greater understanding and a direct method of acquiring LAD suicide statistics is needed. It is suggested that medical examiners, the Centers for Disease Control and Prevention, and other epidemiological organizations proactively evaluate the association between LAD and suicide.

[Dyslipidemia and suicidal risk in patients with psychiatric disorders]

The aim of this work is to study the association between dyslipidemia and suicidal risk in patients with psychiatric pathology. Our study has involved 155 patients suffering from major depressive disorder and 124 schizophrenic patients aged 40.58±12.16 and 43.43±10.60 years, respectively. Total cholesterol (TC), triglycerides (TG) and HDL-c were determined by enzymatic methods, LDL-c was calculated by the Friedewald formula. Plasma cholesterol level was significantly lower among suicidal schizophrenic or depressive patients. There were no significant differences in the others lipid levels. The results of our study suggest that total cholesterol values less than 3.59mmol/L could be an indicator of suicide vulnerability in patients with schizophrenia or major depressive disorder.

Risk of self-harm and nonfatal suicide attempts, and completed suicide in patients with psoriasis: a population-based cohort study

BACKGROUND

Psoriasis is a common inflammatory skin disease, and inflammation may affect suicidal behaviour. Current data on the incidence and risk of suicidal behaviour in patients with psoriasis are scarce.

OBJECTIVES

We investigated the association between psoriasis and the risk of self-harm and suicide attempts and suicides.

METHODS

All Danish patients aged ≥ 18 years with mild or severe psoriasis (cases) from 1 January 1997 to 31 December 2011 were matched on age, sex and calendar time 1 : 5 with healthy controls. The outcome was a diagnosis of self-harm or a nonfatal suicide attempt, or completed suicide. Incidence rates per 10 000 person-years were calculated, and incidence rate ratios (IRRs) and confidence intervals (CIs) were estimated by Poisson regression models.

RESULTS

The study cohort comprised 408 663 individuals, including 57 502 and 11 009 patients with mild and severe psoriasis, respectively. In total 280 cases of self-harm or suicide attempts, and 574 suicides occurred during follow-up. There was no increased risk of self-harm or suicide attempts in patients with mild psoriasis (IRR 1·01, 95% CI 0·17-2·01), but this risk was significantly increased in severe psoriasis (IRR 1·69, 95% CI 1·00-2·84). There was no increased risk of suicides in mild (IRR 1·05, 95% CI 0·84-1·32) or severe psoriasis (IRR 0·78, 95% CI 0·45-1·36). Similar results were found when suicides were confirmed by official forensic investigations, and when psoriasis was compared with atopic dermatitis.

CONCLUSIONS

We found limited evidence to suggest an increased risk of self-harm and nonfatal suicide attempts in patients with psoriasis. Importantly, after adjustment for psoriatic arthritis this risk was no longer significantly increased. The risk of completed suicide was also not increased, regardless of psoriasis severity.

Neutrophil-to-lymphocyte ratio predicting suicide risk in euthymic patients with bipolar disorder: Moderatory effect of family history

BACKGROUND

Neutrophil-to-lymphocyte ratio (NLR) has been independently related to bipolar disorder (BD) and factors associated with suicidal risk. The aim of our study was to explore the relationship between NLR and suicide risk in euthymic BD patients. We also sought to propose a model of interaction between NLR and stress-diathesis factors, leading to suicidal risk in BD.

METHODS

The study group consisted of 83 patients diagnosed with BD (36 suicide attempters; 47 suicide non-attempters), compared to the healthy control group (n=73) and matched according to age, gender, and body mass index (BMI). NLR was measured according to the complete blood count. Mood symptoms have been assessed by Young Mania Rating Scale and Montgomery-Asberg Depression Rating Scale. Early trauma and acute stress were evaluated by Early Trauma Inventory Self Report-Short Form and List of Threatening Experiences Questionnaire, respectively. Suicide risk has been assessed by Suicide Behaviors Questionnaire-Revised (SBQ-R).

RESULTS

Significant correlation was found between NLR and SBQ-R score. The main effects of suicide attempts on NLR, after covarying for confounders, were observed, indicating increased NLR in BD suicide attempters compared to healthy controls. We found significant moderatory effects of family history on NLR relationship to suicidal risk, with NLR being significant positive predictor of suicidal risk only in the patients with positive family history of suicide attempts.

CONCLUSIONS

The results suggest an enhancing effect of positive family history of suicide attempts on predictive effect of NLR on suicide risk. Our data support the idea that immune markers can predict suicide attempt risk in BD, but only in the subpopulation of BD patients with family history of suicide attempts. This could lead to prevention in suicide behavior in the patient population at particular risk of suicide.

Antidepressants normalize elevated Toll-like receptor profile in major depressive disorder

RATIONALE

Abnormalities in Toll-like receptor (TLR) expression in depression have been inferred in part from observed increases in TLR4 levels in peripheral blood mononuclear cells (PBMCs) and postmortem brains of depressed and suicidal patients. Our previous study found differences in the TLR expression in PBMCs between healthy controls and patients with major depressive disorder. Normalization of increased TLR4 in PBMCs by cognitive behavior psychotherapy has been reported. However, the effects of antidepressants remain unknown.

OBJECTIVES

Changes in TLR1-9 expression levels of PBMCs were examined in 56 patients with MDD. The 17-item Hamilton Depression Rating Scale (HAMD-17) and mRNA expression levels of TLRs were assessed in parallel with a housekeeping gene using qRT-PCR before and after treatment with antidepressants.

RESULTS

TLR3, TLR4, TLR5, TLR7, TLR8, and TLR9 were expressed at elevated levels in patients with MDD and were significantly decreased by treatment with antidepressants for 4 weeks. Antidepressant treatment completely normalized TLR3, TLR5, TLR7, TLR8, and TLR9 levels, whereas TLR1, TLR2, TLR4, and TLR6 were decreased to below normal levels. A subgroup analysis found that only TLR3 was significantly higher at baseline in the nonremission group. In addition, a multiple linear regression analysis revealed that only low TLR3 before treatment predicted improvement in HAMD-17 scores.

CONCLUSIONS

These findings suggest that antidepressant treatment exerts anti-inflammatory effects in patients with MDD and identify TLR profiles as a predictor of response to antidepressant therapy. Further studies investigating the effects of manipulating individual TLRs on depression are needed to fully elucidate the underlying mechanism.