The Role of Opiates in Social Pain and Suicidal Behavior

Progesterone receptor distribution in the human hypothalamus and its association with suicide

The human hypothalamus modulates mental health by balancing interactions between hormonal fluctuations and stress responses. Stress-induced progesterone release activates progesterone receptors (PR) in the human brain and triggers alterations in neuropeptides/neurotransmitters. As recent epidemiological studies have associated peripheral progesterone levels with suicide risks in humans, we mapped PR distribution in the human hypothalamus in relation to age and sex and characterized its (co-) expression in specific cell types. The infundibular nucleus (INF) appeared to be the primary hypothalamic structure via which progesterone modulates stress-related neural circuitry. An elevation of the number of pro-opiomelanocortin+ (POMC, an endogenous opioid precursor) neurons in the INF, which was due to a high proportion of POMC+ neurons that co-expressed PR, was related to suicide in patients with mood disorders (MD). MD donors who died of legal euthanasia were for the first time enrolled in a postmortem study to investigate the molecular signatures related to fatal suicidal ideations. They had a higher proportion of PR co-expressing POMC+ neurons than MD patients who died naturally. This indicates that the onset of endogenous opioid activation in MD with suicide tendency may be progesterone-associated. Our findings may have implications for users of progesterone-enriched contraceptives who also have MD and suicidal tendencies.

[How can ketamine be used to manage suicidal risk?]

In France, suicidal behaviors remain a major public health issue. Depressed patients with suicidal ideation have more severe depressive symptoms, a more unfavorable disease course, and a greater number of suicide attempts than patients without suicidal ideation. Unfortunately, conventional antidepressants tend to be less effective in patients with suicidal tendencies than in those without. Nevertheless, promising advancements have emerged with the use of ketamine, which has shown significant and rapid efficacy in reducing the intensity of suicidal ideation in depressed patients within the first 72 h after its administration. Several mechanisms are potentially involved: (1) reduction of anhedonia. It has been demonstrated that ketamine reduces both anhedonia and suicidal ideation. In depressed patients, the reduction of anhedonia observed 2 h after ketamine administration is associated with metabolic changes in the anterior cingulate cortex involved in suicidal ideation; (2) activation of neuroplasticity cascades. The reduction in suicidal ideation within 24 h following ketamine administration is correlated with changes in plasma BDNF levels and is modulated by the Val66Met functional polymorphism of the BDNF gene. Moreover, preclinical and clinical studies have shown that ketamine induces functional and connectivity changes in the prefrontal and anterior cingulate regions, which are strongly implicated in suicidal behaviors; (3) reduction of inflammation. It is now widely accepted that suicidal behaviors are associated with low-grade inflammation, and with elevated quinolinic acid and reduced kynurenic acid levels. Interestingly, predictors of a reduction in suicidal ideation after ketamine infusion include initial severity of suicidal thoughts and depression, as well as baseline blood levels of kynurenic acid; (4) involvement of the opioidergic system. Post-mortem studies have indicated alterations in the opioidergic system related to suicidal behaviors. A recent study suggested that the antisuicidal effect of ketamine may depend on this system because naltrexone, an antagonist of mu opioid receptors, abolished the typical antidepressant effect and reduction in suicidal ideation observed following ketamine administration. In conclusion, ketamine exhibits promising potential in mitigating suicidal ideation - its effects are specific, rapid, albeit temporary. The suggested mechanisms driving its efficacy are multifaceted. Nevertheless, it is yet to be determined whether ketamine administration can effectively prevent suicidal behaviors.

Chronic pain conditions and risk of suicidal behavior: a 10-year longitudinal co-twin control study

BACKGROUND

Understanding the relationship between chronic pain conditions and suicidal behavior-suicide attempt, other intentional self-harm, and death by suicide-is imperative for suicide prevention efforts. Although chronic pain conditions are associated with suicidal behaviors, these associations might be attributed to unmeasured confounding or mediated via pain comorbidity.

METHODS

We linked a population-based Swedish twin study (N=17,148 twins) with 10 years of longitudinal, nationwide records of suicidal behavior from health and mortality registers through 2016. To investigate whether pain comorbidity versus specific pain conditions were more important for later suicidal behavior, we modeled a general factor of pain and two independent specific pain factors (measuring pain-related somatic symptoms and neck-shoulder pain, respectively) based on 9 self-reported chronic pain conditions. To examine whether the pain-suicidal behavior associations were attributable to familial confounding, we applied a co-twin control model.

RESULTS

Individuals scoring one standard deviation above the mean on the general pain factor had a 51% higher risk of experiencing suicidal behavior (odds ratio (OR), 1.51; 95% confidence interval (CI), 1.34-1.72). The specific factor of somatic pain was also associated with increased risk for suicidal behavior (OR, 1.80; 95% CI, 1.45-2.22]). However, after adjustment for familial confounding, the associations were greatly attenuated and not statistically significant within monozygotic twin pairs (general pain factor OR, 0.89; 95% CI, 0.59-1.33; somatic pain factor OR, 1.02; 95% CI, 0.49-2.11) CONCLUSION: Clinicians might benefit from measuring not only specific types of pain, but also pain comorbidity; however, treating pain might not necessarily reduce future suicidal behavior, as the associations appeared attributable to familial confounding.

Pharmacological Strategies for Suicide Prevention Based on the Social Pain Model: A Scoping Review

Suicidal behaviour is a public health problem whose magnitude is both substantial and increasing. Since many individuals seek medical treatment following a suicide attempt, strategies aimed at reducing further attempts in this population are a valid and feasible secondary prevention approach. An evaluation of the available evidence suggests that existing treatment approaches have a limited efficacy in this setting, highlighting the need for innovative approaches to suicide prevention. Existing research on the neurobiology of social pain has highlighted the importance of this phenomenon as a risk factor for suicide, and has also yielded several attractive targets for pharmacological strategies that could reduce suicidality in patients with suicidal ideation or a recent attempt. In this paper, the evidence related to these targets is synthesized and critically evaluated. The way in which social pain is related to the “anti-suicidal” properties of recently approved treatments, such as ketamine and psilocybin, is examined. Such strategies may be effective for the short-term reduction in suicidal ideation and behaviour, particularly in cases where social pain is identified as a contributory factor. These pharmacological approaches may be effective regardless of the presence or absence of a specific psychiatric diagnosis, but they require careful evaluation.

Multiple suicide attempts associated with addiction to tramadol

BACKGROUND

The opioid tramadol is used as analgesic drug, and more recently was also proposed for the management of major depressive disorder. However, growing evidence suggests a link between opioid system dysfunction and suicidal behaviors, raising the question of tramadol use in view of the high addictive and suicidal risk. Here, we present the case of a young adult woman with multiple suicide attempts related to tramadol addiction.

CASE PRESENTATION

A 25-year-old woman was admitted for suicide attempt by phlebotomy in the Department of Psychiatric Emergency and Acute Care, Montpellier (France), in March 2020. The suicide attempt occurred 3 days after an abrupt tramadol withdrawal. In 2018, due to spinal disc herniation, she had a first prescription of tramadol to which she became addicted. The patient described an effect on psychological pain and suicidal ideation. However, she had to increase tramadol dose to obtain the desired effects, and for several months her intake was 2 000 mg per day. When she could not obtain tramadol any longer, suicidal ideation and psychological pain increased, leading to the suicide attempt. At the time of a worldwide opioid crisis that contributes to increasing suicidal behaviors, this case raises questions about tramadol prescription (often considered to be less addictive and with lower abuse potential) to individuals at risk of suicide.

Characteristics and treatment outcome of suicidal depression: Two large naturalistic cohorts of depressed outpatients

OBJECTIVE

The emergence of new drugs for managing suicidal ideation (e.g. ketamine) raises the question of whether suicidal depression (i.e. moderate to severe depression with concomitant suicidal ideation) is a specific depression phenotype. Therefore, this study characterized patients with suicidal depression (baseline clinical characteristics, suicidal ideation and depression evolutions, suicide risk) in two large cohorts of outpatients with depression.

METHODS

LUEUR and GENESE are two large, prospective, naturalistic cohorts of French adult outpatients with depression (Diagnostic and Statistical Manual of Mental Disorders, fourth edition, criteria), treated and followed up for 6 weeks. Depression severity was assessed with the Hospital Anxiety and Depression Scale, and suicidal ideation with the suicidal item of the Montgomery-Åsberg Depression Rating Scale. Patients with moderate or severe depression (Hospital Anxiety and Depression Scale-Depression subscale score >11) were selected and classified as without suicidal ideation (suicidal item of the Montgomery-Åsberg Depression Rating Scale <2), with moderate suicidal ideation (suicidal item of the Montgomery-Åsberg Depression Rating Scale [2; 3]) and with severe suicidal ideation (suicidal item of the Montgomery-Åsberg Depression Rating Scale ⩾4).

RESULTS

Baseline clinical features were more severe (e.g. higher anxiety and depression scores) in depressed patients with moderate/severe suicidal ideation. Depression remission after treatment was less frequent among patients with severe suicidal ideation. The risk of suicide attempt during the follow-up was threefold higher in patients with suicidal ideation among those 10% had persistent suicidal ideation.

CONCLUSION

Suicidal depression could be a specific depression phenotype with more severe clinical characteristics, less frequent depression remission, suicidal ideation persistence and higher suicide attempt risk, despite antidepressant treatment. It seems that novel therapeutic strategies could be needed.

The role of social isolation in opioid addiction

Humans are social animals: social isolation hurts people both psychologically and physically. Strong, positive social bonds help people to live longer and healthier lives compared with their more isolated peers. Opioid use disorder is associated with feelings of social isolation, an increased risk of suicide and, at the community level, lower social capital. I propose a psychobiological mechanistic explanation that contributes to the association between opioid use and social isolation. The endogenous opioid system plays a central role in the formation and maintenance of social bonds across the life span and has been investigated primarily through the framework of the brain opioid theory of social attachment. In primates, maternal-infant bonding and social play are both impaired by the administration of naltrexone (an opioid antagonist), and in humans, the chronic use of opioids appears to be particularly (relative to other drugs) corrosive to close relationships. Social isolation may play a role in the development and exacerbation of opioid use disorder. Taken together, work on the brain’s opioid system suggests a possible mechanistic basis for bidirectional causal links between social isolation and opioid use disorder. Evaluation of this hypothesis would benefit from longitudinal psychosocial and neuropsychopharmacological investigations.

Traumatic grief research and care in the aftermath of the COVID-19 pandemic

BACKGROUND

A significant increase in the number of individuals suffering from prolonged grief disorder is expected in the aftermath of the COVID-19 pandemic for two main reasons. First, the number of excess deaths has contributed to an immense number of bereaved individuals. Second, recent literature has shown that circumstances associated with COVID-19 deaths may be contributing to increased risk for the development of prolonged grief disorder.

OBJECTIVE

To best support those affected by loss during the COVID-19 pandemic, it is important to inform clinicians and researchers about the development, the nature and the treatment of prolonged grief disorder and employ sound research.

METHOD

In this editorial, we discuss important themes regarding prolonged grief disorder in the aftermath of the COVID-19 pandemic, to gather and present useful information for clinicians and researchers.

RESULTS

The following themes were addressed: 1. Harmonization in the diagnosis of prolonged grief disorder. 2. Screening tools and interventions. 3. Pharmacotherapy. 4. Special attention for the elderly. 5. Special attention for children and adolescents. 6. A causal system perspective for understanding grief and prolonged grief disorder.

CONCLUSIONS

If those involved in bereavement research and care manage to collaborate, the tragic consequences of COVID-19 might catalyse improvement of care for those most impaired following the loss of a loved one.