The role of inflammatory cytokines in suicidal behavior: A systematic review

There is growing evidence that inflammatory mediators play a critical role in the pathophysiology of both major depression and suicidal behavior. Immunological differences have been reported in both major affective disorders and suicidal behavior. Specifically, increased levels of pro-inflammatory cytokines have been shown to correlate with the severity of depression and various cytokines have been identified as potentially important in understanding the pathophysiology of major affective disorders/suicidality. We aimed to conduct a systematic review of the current literature to investigate the association between inflammatory cytokines and suicidal behavior. Only articles from peer-reviewed journals were selected for inclusion in the present review. Most studies documented the association between suicidality and IL2, IL-6, IL-8, TNF-α and VEGF levels that have been found altered in suicidal behavior. The presence of major depressive disorder (MDD) with suicidal ideation/attempts was associated with differences in inflammatory cytokine profile when compared to that without suicidal ideation/attempts. Most suicide attempters or subjects with suicidal ideation showed an imbalance of the immune system but this does not imply the existence of a causal link. Also, not all studies demonstrated a positive correlation between inflammatory cytokines and suicidal behavior. Further additional studies should elucidate the molecular mechanisms of the immune activation pathways underlying suicidality. © 2013 Elsevier B.V. and ECNP

Bisexuality and Suicide: A Systematic Review of the Current Literature

Introduction: Many studies of lesbian, gay, and bisexual youth have demonstrated that individuals reporting a bisexual orientation have a particularly high risk of suicidal behavior and substance abuse. It has been also suggested that bisexual individuals (both men and women) have higher rates of depression and anxiety compared with homosexual and heterosexual groups. Aim: The aim of the present article was to determine whether or not an association between bisexuality and suicidal behavior exists and to analyze risk factors for suicidal behavior in bisexual individuals. Main Outcome Measures: The combined search strategies yielded a total of 339 records screened from PubMed, Scopus, and Web of Knowledge. Duplicate articles, articles that were not in English, and those that did not analyze bisexuality separately from homosexuality were excluded. A quality assessment was performed for each study included. Methods: A careful systematic review of the literature was conducted investigating the potential bisexuality-suicidal behavior link. A total of 77 articles from peer-reviewed journals were considered, and the most relevant (N=19) were selected for this review. Results: Individuals reporting a bisexual orientation had an increased risk of suicide attempts and ideation compared with their homosexual and heterosexual peers. Risk factors included related victimization, peer judgments, and family rejection. Bisexual individuals also reported higher rates of mental illness and substance abuse. Conclusions: Bisexual individuals may experience more psychological distress and mental health problems than individuals who identify with a homosexual or heterosexual orientation. Clinicians should consider the potential for suicidal behaviors in bisexual individuals and be alert for increased mental health problems and poor social integration. © 2014 International Society for Sexual Medicine

Tryptophan and Kynurenine Metabolites: Are They Related to Depression?

BACKGROUND: Some previous studies found decreased concentrations of L-tryptophan (TRY) and increased L-kynurenine (KYN), or its metabolites, in the body fluids of subjects with major depressive disorder (MDD), sometimes in association with suicidal behavior. Such changes might indicate a shift of TRY away from serotonin production, possibly via the effects of inflammatory peptides which activate indoleamine-2,3-dioxygenase. However, these findings have been inconsistent and require replication. METHODS: We used sensitive liquid-chromatography mass spectrometry methods to assay plasma concentrations of TRY, 5-hydroxyindoleacetic acid (5-HIAA), and KYN and its metabolites (anthranilic acid and xanthurenic acid). We compared 49 hospitalized, depressed subjects diagnosed with MDD (n = 37) or bipolar disorder (BD, n = 12), with (n = 22) or without (n = 27) previous suicide attempts, to 78 healthy, ambulatory controls of similar age and sex (total n = 127). FINDINGS: Contrary to expectation, TRY plasma concentrations were higher, KYN plasma concentrations were lower, and their ratio much higher in depressed subjects, with no relationship to suicidal history. Concentrations of 5-HIAA and the kynurenine metabolites did not differ between depressed and healthy subjects. CONCLUSIONS: These findings are opposite to expectations and not consistent with a hypothesized increased conversion from TRY to KYN in depressed subjects. In addition, we found no evidence of altered production of serotonin as 5-HIAA concentration was unchanged. None of the observed changes was associated with a history of suicide attempt

Insomnia as a predictor of high-lethality suicide attempts

IntroductionResearch has demonstrated that patients with insomnia are at an increased risk of experiencing suicidal ideation and/or making a suicide attempt. ObjectivesTo evaluate the relation between insomnia and suicidal behaviour. AimsTo examine factors associated with a diagnosis of insomnia in patients admitted to an Emergency Department (ED) and assessed by the psychiatrist in charge. MethodsParticipants were 843 patients consecutively admitted to the ED of Sant'Andrea Hospital in Rome, between January 2010 and December 2011. All patients admitted were referred to a psychiatrist. A clinical interview based on the Mini International Neuropsychiatric Interview (MINI) and a semi-structured interview was conducted. Patients were asked about ongoing' suicidal ideation or plans for suicide. ResultsForty-eight percent of patients received a diagnosis of bipolar disorder (BD), major depressive disorder (MDD) or an anxiety disorder; whereas, 17.1% were diagnosed with Schizophrenia or other non-affective psychosis. Patients with insomnia (compared to patients without insomnia) more frequently had a diagnosis of BD (23.9% vs. 12.4%) or MDD (13.3% vs. 9.5%; p<0.001). Moreover, patients with insomnia less frequently had attempted suicide in the past 24h (5.3% vs. 9.5%; p<0.05) as compared with other patients, but those patients with insomnia who attempted suicide more frequently used a violent method (64.3% vs. 23.6%; p<0.01) compared to other suicide attempters. ConclusionsOur results do not support an association between insomnia and suicidal behaviour. However, suicide attempters with insomnia more frequently used violent methods, and this phenomenon should be taken into serious consideration by clinicians