Circulating levels of oxytocin may be elevated in complicated grief: a pilot study

From love to pain: is oxytocin the key to grief complications?

While most adults confronted with the death of a loved one manage to grieve, about 10-20% of individuals develop complicated grief, characterized by persistent distress and impaired social skills, or pathological grief, defined by the onset or decompensation of a psychiatric disorder. Little is known about the biological causes of these grief complications. Recent work suggests that oxytocin, a major neuroendocrine hormone regulating many neurocognitive mechanisms, may be involved in this process. Oxytocin is widely studied and well known for its impact on the mother-child bond and hormonal and brain systems related to attachment and social interactions. In this article, we propose a neurocognitive model of grief complications based on existing data on the role of oxytocin in interpersonal attachment and its impact on brain activity. We suggest that complicated grief is associated with dysfunctional cerebral oxytocinergic signaling and persistent hyperactivation of the nucleus accumbens. This mechanism is involved in limiting the reduction of interpersonal attachment to the deceased during acute phases and in searching for new interpersonal relationships during the recovery phase. We show how the exploration of cerebral oxytocinergic signaling would improve the understanding of physiological grief mechanisms in the general population and could allow the development of new therapeutic perspectives against the complications of grief.

A pull to be close: The differentiating effects of oxytocin and grief stimulus type on approach behavior in complicated grief

Theoretical models of complicated grief (CG) suggest that maladaptive motivational tendencies (e.g., perseverative proximity-seeking of the deceased; excessive avoidance of reminders) interfere with a person's ability to recover from their loved one's death. Due in part to conflicting evidence, little mechanistic understanding of how these behaviors develop in grief exists. We sought to (1) identify behavioral differences between CG and non-CG groups based on approach/avoidance bias for grief-, deceased-, and social-related stimuli, and (2) test the role of the neuropeptide oxytocin in shaping approach/avoidance bias. Widowed older adults with (n = 17) and without (n = 22) CG completed an approach/avoidance task measuring implicit bias for both personalized and non-specific grief-related stimuli (among other stimuli). In a double-blinded, randomized, counterbalanced design, each participant attended both an intranasal oxytocin session and a placebo session. Aims were to (1) identify differential effects of CG and stimulus type on implicit approach/avoidance bias [placebo session], and (2) investigate interactive effects of CG, stimulus type, and oxytocin vs. placebo on approach/avoidance bias [both sessions]. In the placebo session, participants in the non-CG group demonstrated an approach bias across all stimuli. Intranasal oxytocin had an overall slowing effect on the CG group's response times. Further, oxytocin decreased avoidance bias in response to photos of the deceased spouse in the CG group only. Findings support the hypothesis that oxytocin has a differential effect on motivational tendency in CG compared to non-CG, strengthening evidence for its role in CG. Findings also emphasize the need to consider differences in personalized vs. generic stimuli when designing grief-relevant tasks.

Exploring the role of empathy in prolonged grief reactions to bereavement

Grief reactions to the bereavement of a close individual could involve empathy for pain, which is fundamental to social interaction. To explore whether grief symptoms interact with social relatedness to a person to whom one directs empathy to modulate the expression of empathy, we administered an empathy task to 28 bereaved adults during functional magnetic resonance imaging, in which participants were subliminally primed with facial stimuli (e.g., faces of their deceased or living relative, or a stranger), each immediately followed by a visual pain stimulus. Individuals' grief severity promoted empathy for the pain stimulus primed with the deceased's face, while it diminished the neural response to the pain stimulus primed with the face of either their living relative or a stranger in the medial frontal cortex (e.g., the right dorsal anterior cingulate cortex). Moreover, preliminary analyses showed that while the behavioral empathic response was promoted by the component of "longing" in the deceased priming condition, the neural empathic response was diminished by the component of "avoidance" in the stranger priming condition. Our results suggest an association between grief reactions to bereavement and empathy, in which grief symptoms interact with interpersonal factors to promote or diminish empathic responses to others' pain.

Interactions between the κ opioid system, corticotropin-releasing hormone and oxytocin in partner loss

Selective adult social attachments, or ‘pair bonds’, represent central relationships for individuals in a number of social species, including humans. Loss of a pair mate has emotional consequences that may or may not diminish over time, and that often translate into impaired psychological and physical health. In this paper, we review the literature on the neuroendocrine mechanisms for the emotional consequences of partner loss, with a special focus on hypothesized interactions between oxytocin, corticotropin-releasing hormone and the κ opioid system.

This article is part of the theme issue ‘Interplays between oxytocin and other neuromodulators in shaping complex social behaviours’.

Peripheral oxytocin concentrations in psychiatric disorders - A systematic review and methanalysis: Further evidence

Increased interest in understanding how changes in the oxytocinergic system are associated with the etiology and progression of psychiatric disorders has currently boosted the publication of studies. We present a systematic literature review followed by meta-analyses assessing whether peripheral oxytocin (OXT) levels among psychiatric patients differ from healthy controls, considering the moderating role of methodological aspects and samples' characteristics. The following electronic databases were searched: PubMed, Web of Science, PsycINFO, SciELO, LILACS, and Scopus. Fifty-five papers were included in the analysis, and nine independent meta-analyses were performed according to the different diagnoses. Lower OXT concentrations were found in groups of specific disorders (i.e., schizophrenia, restricting and binge-eating/purging subtypes of anorexia nervosa, and borderline personality disorder) with medium to large effect sizes. Great heterogeneity was found among the studies, so that caution is needed to interpret the results. High OXT levels with an effect size of the same magnitude were found for bipolar disorder - type I and obsessive disorder. In contrast, no differences were found for bulimia, autism spectrum, depression, or social anxiety. No meta-analyses were performed for body dysmorphic disorder, post-traumatic stress disorder, or trichotillomania because only one study was identified for each of these disorders. Altered endogenous OXT concentrations are found in several disorders addressed and must be analyzed according to each disorder's specificities.

The brain oxytocin and corticotropin-releasing factor systems in grieving mothers: What we know and what we need to learn

The bond between a mother and her child is the strongest bond in nature. Consequently, the loss of a child is one of the most stressful and traumatic life events that causes Prolonged Grief Disorder in up to 94 % of bereaved parents. While both parents are affected, mothers are of higher risk to develop mental health complications; yet, very little research has been done to understand the impact of the loss of a child, stillbirth and pregnancy loss on key neurobiological systems. The emotional impact of losing a child, e.g., Prolonged Grief Disorder, is likely accompanied by dysregulations in neural systems important for mental health. Among those are the neuropeptides contributing to attachment and stress processing. In this review, we present evidence for the involvement of the brain oxytocin (OXT) and corticotropin-releasing factor (CRF) systems, which both play a role in maternal behavior and the stress response, in the neurobiology of grief in mothers from a behavioral and molecular point of view. We will draw conclusions from reviewing relevant animal and human studies. However, the paucity of research on the tragic end to an integral bond in a female's life calls for the need and responsibility to conduct further studies on mothers experiencing the loss of a child both in the clinic and in appropriate animal models.

Prolonged Grief Disorder: Course, Diagnosis, Assessment, and Treatment

Losing a loved one is one of life's greatest stressors. Although most bereaved individuals navigate through a period of intense acute grief that lessens with time, approximately 10% will develop a prolonged grief condition. This review provides an overview of the course of grief and describes risk factors for developing prolonged grief disorder. The evolution of the prolonged grief disorder diagnosis, including the latest criteria sets for ICD-11 and DSM-5, as well as common comorbid conditions and differential diagnosis are discussed. Clinically useful self-report and clinician-rated measures for assessing symptom constructs and overall prolonged grief disorder severity, evidence-based psychotherapies (such as complicated grief treatment), as well as evidence about pharmacologic approaches are presented. Finally, the authors discuss important future directions, including a potential increase in prolonged grief disorder cases due to the COVID-19 pandemic.

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.

Salivary and plasmatic oxytocin are not reliable trait markers of the physiology of the oxytocin system in humans

Single measurements of salivary and plasmatic oxytocin are used as indicators of the physiology of the oxytocin system. However, questions remain about whether they are sufficiently stable to provide valid trait markers of the physiology of the oxytocin system, and whether salivary oxytocin can accurately index its plasmatic concentrations. Using radioimmunoassay, we measured baseline plasmatic and/or salivary oxytocin from two independent datasets. We also administered exogenous oxytocin intravenously and intranasally in a triple dummy, within-subject, placebo-controlled design and compared baseline levels and the effects of routes of administration. Our findings question the use of single measurements of baseline oxytocin concentrations in saliva and plasma as valid trait markers of the physiology of the oxytocin system in humans. Salivary oxytocin is a weak surrogate for plasmatic oxytocin. The increases in salivary oxytocin observed after intranasal oxytocin most likely reflect unabsorbed peptide and should not be used to predict treatment effects.

The neurobiological reward system in Prolonged Grief Disorder (PGD): A systematic review

Prolonged Grief Disorder (PGD) is a debilitating condition affecting between 7% and 10% of bereaved individuals. Past imaging and psychological studies have proposed links between PGD's characteristic symptoms - in particular, profound yearning - and the neural reward system. We conducted a systematic review to investigate this connection. On December 19, 2019, we searched six bibliographic databases for data on the neurobiology of grief and disordered grief. We excluded studies of the hypothalamic-pituitary-adrenal (HPA) axis, animal studies, and reviews. After abstract and full-text screening, twenty-four studies were included in the final review. We found diverse evidence for the activation of several reward-related regions of the brain in PGD. The data reviewed suggest that compared to normative grief, PGD involves a differential pattern of activity in the amygdala and orbitofrontal cortex (OFC); likely differential activity in the posterior cingulate cortex (PCC), rostral or subgenual anterior cingulate cortex (ACC), and basal ganglia overall, including the nucleus accumbens (NAc); and possible differential activity in the insula. It also appears that oxytocin signaling is altered in PGD, though the exact mechanism is unclear. Our findings appear to be consistent with, though not confirmative of, conceptualizing PGD as a disorder of reward, and identify directions for future research.

Neuroendocrine mechanisms of grief and bereavement: A systematic review and implications for future interventions

Bereavement is associated with many negative behavioural, psychological and physiological consequences and leads to an increased risk of mortality and morbidity. However, studies specifically examining neuroendocrine mechanisms of grief and bereavement have yet to be reviewed. This systematic review is a synthesis of the latest evidence in this field and aims to draw conclusions about the implications of neurobiological findings on the development of new interventions. PRISMA guidelines for systematic reviews were used to search for articles assessing neuroendocrine correlates of grief. Findings were qualitatively summarised. The National Heart, Lung, and Blood Institute Study Assessment Tool was used to assess the quality of the included studies. Out of 460 papers, 20 met the inclusion criteria. However, most were of fair quality only. As a neuroendocrine marker, the majority of the studies reported cortisol as the outcome measure and found elevated mean cortisol levels, flattened diurnal cortisol slopes and higher morning cortisol in bereaved subjects. Cortisol alterations were moderated by individual differences such as emotional reaction to grief, depressive symptoms, grief severity, closeness to the deceased and age or gender. Research on neuroendocrine mechanisms of grief is still in its early stages regarding grief measures and the use and timing of neuroendocrine assessments. Most of the studies focus on cortisol as outcome, and only limited data exist on other biomarkers such as oxytocin. Future research might consider assessing a broader range of neuroendocrine markers and use longitudinal designs with a focus on the psychobiological reactions to loss. Based on this, individually tailored psychosocial interventions, possibly in the palliative care context, might be developed to prevent prolonged grief disorder.

Influence of intranasal oxytocin on fear consolidation in healthy humans

Background

Although recent data in healthy humans suggestthat treatment with intranasal oxytocin (OT) may facilitate extinction recall,to date, little is known about the effects of OT on memory consolidationprocesses.

Aim

To examine the effect of intranasal administration of OT compared with placebo on memory consolidation blockade of a de novo fear memory in a classical 2-day fear conditioning procedure.

Results

There were no significant differences between the OT and the placebo groups on the first two extinction trials (mean (SD)=0.01 (0.39) vs 0.15 (0.31), t=−1.092, p=0.28). Similarly, during early extinction, analysis of variance for repeated measures failed to show significant main effects of extinction trials: trials (F(4, 112)=1.58, p=0.18), drug (F(1, 112)=0.13, p=0.72) or drug × trials interaction (F(4, 112)=0.76, p=0.56).

Conclusion

Our results suggest that OT administered in a double-blind fashion immediately after fear conditioning does not significantly reduce consolidation of fear learning as measured by a differential skin conductance response tested at the beginning of extinction.

Pharmacotherapy of anxiety disorders in the 21st century: A call for novel approaches

While limited advances have occurred in the past 30 years in the pharmacological management of anxiety and stress-related disorders, novel molecular pathways both within and without the monoamine systems are currently under investigation and offer promising new avenues for more effective future treatments. Enhancing psychotherapy approaches with pharmacological compounds offers the potential to not only transform the standard of care of these conditions, but more broadly would introduce a paradigm shift in the way medications and their role in psychiatric care are conceptualised. Although further human trials and more translational research are sorely needed, continuing to pursue innovative mechanisms and treatments is hoped to yield substantial results in the coming decades and a departure from the reliance on chemical agents of the 20th century.

A decennial review of psychotraumatology: what did we learn and where are we going?

On 6 December 2019 we start the 10th year of the European Journal of Psychotraumatogy (EJPT), a full Open Access journal on psychotrauma. This editorial is part of a special issue/collection celebrating the 10 years anniversary of the journal where we will acknowledge some of our most impactful articles of the past decade (also discussed below and marked with * in the reference list). In this editorial the editors present a decennial review of the field addressing a range of topics that are core to both the journal and to psychotraumatology as a discipline. These include neurobiological developments (genomics, neuroimaging and neuroendocrine research), forms of trauma exposure and impact across the lifespan, mass trauma and early interventions, work-related trauma, trauma in refugee populations, and the potential consequences of trauma such as PTSD or Complex PTSD, but also resilience. We address innovations in psychological, medication (enhanced) and technology-assisted treatments, mediators and moderators like social support and finally how new research methods help us to gain insights in symptom structures or to better predict symptom development or treatment success. We aimed to answer three questions 1. Where did we stand in 2010? 2. What did we learn in the past 10 years? 3. What are our knowledge gaps? We conclude with a number of recommendations concerning top priorities for the future direction of the field of psychotraumatology and correspondingly the journal.