In addition to obtaining a history of suicidal behavior, clinicians may find it useful to assess patients' current level of pessimism, aggressive/impulsive traits, and comorbidity with substance use disorders, including nicotine-related disorders, to help identify patients at risk for suicidal behavior after major depression. Interventions such as aggressive pharmacotherapeutic prophylaxis to prevent relapse or recurrence of depressive symptoms may protect such at-risk individuals from future suicidal behavior.

Religious affiliation is associated with less suicidal behavior in depressed inpatients. After other factors were controlled, it was found that greater moral objections to suicide and lower aggression level in religiously affiliated subjects may function as protective factors against suicide attempts. Further study about the influence of religious affiliation on aggressive behavior and how moral objections can reduce the probability of acting on suicidal thoughts may offer new therapeutic strategies in suicide prevention.

Objective Pharmacotherapy to rapidly relieve suicidal ideation in depression may reduce suicide risk. Rapid reduction in suicidal thoughts after ketamine treatment has mostly been studied in patients with low levels of suicidal ideation. Method This randomized clinical trial tested the effect of adjunctive sub-anesthetic intravenous ketamine on clinically significant suicidal ideation in major depressive disorder (MDD). Adults (N=80) with current MDD and score ≥4 on the Scale for Suicidal Ideation (SSI), of whom 54% (N=43) were taking antidepressant medication, were randomized to ketamine or midazolam infusion. The primary outcome was Day 1 SSI score (24 hours post-infusion). Other outcomes included global depression and adverse effects. Results Reduction of SSI score was 4.96 points greater after ketamine compared with midazolam at Day 1 (95% confidence interval (CI)=2.33 to 7.59; p=0.0003; Cohen’s d=0.75). Proportion of responders (≥50% reduction in SSI) at Day 1 was 55% after ketamine and 30% after midazolam (OR=2.85 (95% CI=1.14 to 7.15); p=0.0237; NNT=4.00). Improvement in the Profile of Mood States (POMS) depression subscale was greater at Day 1 compared with midazolam treatment (Estimate=7.65 (95% CI=1.36 to 13.94), df=75, t=2.42, p=0.0178), and this effect mediated 33.6% of ketamine’s effect on SSI score. Side effects were short-lived. Benefit was sustained for up to six weeks with clinical pharmacotherapy. Conclusions Adjunctive ketamine demonstrated greater reduction of clinically significant suicidal ideation in depressed patients within 24 hours compared to midazolam, partially independent of antidepressant effect. Research is needed to understand ketamine’s mechanism of action and to develop safe, longer-term treatment.

Background Inflammation has been linked to depression and suicide risk. One inflammatory process that has been minimally investigated in this regard is cytokine-stimulated production of kynurenine (KYN) from tryptophan (TRP). Recent data suggest that KYN increases in cerebrospinal fluid (CSF) are associated with depressive symptoms secondary to immune activation. KYN may alter dopaminergic and glutamatergic tone, thereby contributing to increased arousal, agitation and impulsivity - important risk factors in suicide. We hypothesized that patients with Major Depressive Disorder (MDD) and a history of suicide attempt would have higher levels of KYN than depressed nonattempters, who in turn would have higher levels than healthy volunteers. Methods Plasma KYN, TRP, and neopterin were assayed by high performance liquid chromatography in three groups: healthy volunteers (n=31) and patients with MDD with (n=14) and without (n=16) history of suicide attempt. Analysis of variance tested for group differences in KYN levels. Results KYN levels differed across groups (F=4.03, df=(2,58), p=0.023): a priori planned contrasts showed that KYN was higher in the MDD suicide attempter subgroup compared with MDD non-attempters (t=2.105, df=58, p=0.040), who did not differ from healthy volunteers (t=0.418, df=58, p=0.677). In post-hoc testing, KYN but not TRP was associated with attempt status, and only suicide attempters exhibited a positive correlation of the cytokine activation marker neopterin with the KYN:TRP ratio, suggesting that KYN production may be influenced by inflammatory processes among suicide attempters. Conclusions These preliminary results suggest that KYN and related molecular pathways may be implicated in the pathophysiology of suicidal behavior.

Objective-Whether sex differences exist in clinical risk factors associated with suicidal behavior is unknown. The authors postulated that among men with a major depressive episode, aggression, hostility, and history of substance misuse increase risk for future suicidal behavior, while depressive symptoms, childhood history of abuse, fewer reasons for living, and borderline personality disorder do so in depressed women.Method-Patients with DSM-III-R major depression or bipolar disorder seeking treatment for a major depressive episode (N=314) were followed for 2 years. Putative predictors were tested with Cox proportional hazards regression analysis.Results-During follow-up, 16.6% of the patients attempted or committed suicide. Family history of suicidal acts, past drug use, cigarette smoking, borderline personality disorder, and early parental separation each more than tripled the risk of future suicidal acts in men. For women, the risk for future suicidal acts was sixfold greater for prior suicide attempters; each past attempt increased future risk threefold. Suicidal ideation, lethality of past attempts, hostility, subjective depressive symptoms, fewer reasons for living, comorbid borderline personality disorder, and cigarette smoking also increased the risk of future suicidal acts for women.Conclusions-These findings suggest that the importance of risk factors for suicidal acts differs in depressed men and women. This knowledge may improve suicide risk evaluation and guide future research on suicide assessment and prevention.Sex differences in suicidal behavior have long been recognized (1)(2)(3)(4)(5). Studies have shown that men have higher suicide rates (1), while women are at higher risk for suicide attempts (2, 5). Possible explanations include differences in the propensity to use lethal means, suicidal intent, and the use of substances within the context of suicidal behavior (3, 6).Few cross-sectional studies have compared sex differences in the characteristics of suicide attempters. Adolescent male suicide victims are more likely to have conduct and substance use disorders, while female adolescents more frequently suffer from mood or anxiety disorders and have attempted suicide before (6). Among adolescents and young adults (2), female attempters were more likely to have posttraumatic stress disorder; attempts by males were more often triggered by financial problems. Four prospective studies (7-10) have compared risk factors for suicidal behavior in the two genders. Two studies of overlapping study groups examined 1,026 depressed melancholic inpatients and showed that, compared to matched depressed comparison subjects, female suicide victims more often were unmarried, were noncompliant with treatment, and had previously attempted suicide, while NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript suicide in men was related to heredity for psychosis and brittle or sensitive personality (7,9). Another multisite prospective study of 3,130 teenagers assessed anger at oneself, ...

The greater rate of suicide attempts among patients with comorbid PTSD and major depressive episode was not due to differences in substance use, childhood abuse, or cluster B personality disorders.

No abstract

In this data set of bipolar patients we noted an intriguing picture of two clusters of suicide attempts. Hostility was the strongest risk factor. These findings may have implications in both the identification of at-risk patients and the timing of clinical interventions including aggressive pharmacotherapeutic prophylaxis to prevent relapse or recurrence of depressive symptomatology.