Future Directions in the Study of Early-Life Stress and Physical and Emotional Health: Implications of the Neuroimmune Network Hypothesis

Treatment-resistant depression: molecular mechanisms and management

Due to the heterogeneous nature of depression, the underlying etiological mechanisms greatly differ among individuals, and there are no known subtype-specific biomarkers to serve as precise targets for therapeutic efficacy. The extensive research efforts over the past decades have not yielded much success, and the currently used first-line conventional antidepressants are still ineffective for close to 66% of patients. Most clinicians use trial-and-error treatment approaches, which seem beneficial to only a fraction of patients, with some eventually developing treatment resistance. Here, we review evidence from both preclinical and clinical studies on the pathogenesis of depression and antidepressant treatment response. We also discuss the efficacy of the currently used pharmacological and non-pharmacological approaches, as well as the novel emerging therapies. The review reveals that the underlying mechanisms in the pathogenesis of depression and antidepressant response, are not specific, but rather involve an interplay between various neurotransmitter systems, inflammatory mediators, stress, HPA axis dysregulation, genetics, and other psycho-neurophysiological factors. None of the current depression hypotheses sufficiently accounts for the interactional mechanisms involved in both its etiology and treatment response, which could partly explain the limited success in discovering efficacious antidepressant treatment. Effective management of treatment-resistant depression (TRD) requires targeting several interactional mechanisms, using subtype-specific and/or personalized therapeutic modalities, which could, for example, include multi-target pharmacotherapies in augmentation with psychotherapy and/or other non-pharmacological approaches. Future research guided by interaction mechanisms hypotheses could provide more insights into potential etiologies of TRD, precision biomarker targets, and efficacious therapeutic modalities.

Childhood adversity, accelerated GrimAge, and associated health consequences

Childhood adversity is linked to psychological, behavioral, and physical health problems, including obesity and cardiometabolic disease. Epigenetic alterations are one pathway through which the effects of early life stress and adversity might persist into adulthood. Epigenetic mechanisms have also been proposed to explain why cardiometabolic health can vary greatly between individuals with similar Body Mass Index (BMIs). We evaluated two independent cross-sectional cohorts of adults without known medical illness, one of which explicitly recruited individuals with early life stress (ELS) and control participants (n = 195), and the other a general community sample (n = 477). In these cohorts, we examine associations between childhood adversity, epigenetic aging, and metabolic health. Childhood adversity was associated with increased GrimAge Acceleration (GAA) in both cohorts, both utilizing a dichotomous yes/no classification (both p < 0.01) as well as a continuous measure using the Childhood Trauma Questionnaire (CTQ) (both p < 0.05). Further investigation demonstrated that CTQ subscales for physical and sexual abuse (both p < 0.05) were associated with increased GAA in both cohorts, whereas physical and emotional neglect were not. In both cohorts, higher CTQ was also associated with higher BMI and increased insulin resistance (both p < 0.05). Finally, we demonstrate a moderating effect of BMI on the relationship between GAA and insulin resistance where GAA correlated with insulin resistance specifically at higher BMIs. These results, which were largely replicated between two independent cohorts, suggest that interactions between epigenetics, obesity, and metabolic health may be important mechanisms through which childhood adversity contributes to long-term physical and metabolic health effects.

Associations of DNA-methylation measures of biological aging with social disparities in child and adolescent mental health

Children who experience environmental adversities are at increased risk of both internalizing and externalizing disorders. Epigenetic mechanisms may regulate the influence of environmental adversities on mental health. We examined the hypothesis that salivary DNA-methylation patterns of pace of biological aging (DunedinPoAm) and inflammation (DNAm-CRP) are socially stratified and associated with mental health in 1,183 children (609 female, age M=13.6y) from the Texas Twin Project. Analyses were preregistered. Participants' DNA-methylation algorithms and psychiatric symptoms differed by socioeconomic contexts and race/ethnicity. Children with more parent-reported internalizing symptoms had higher DunedinPoAm and DNAm-CRP scores, and children with more aggression problems had higher DNAm-CRP. DunedinPoAm partially mediated advantage of White racial identity on internalizing. Similarly, DNAm-CRP partially mediated advantage of higher family socioeconomic contexts and, in a separate model, White racial identity on reduced internalizing symptoms. Children's epigenetic measures of pace of biological aging and inflammation are associated with social inequalities and mental health.

Threats to social safety and neuro-inflammatory mechanisms underlying sexual orientation disparities in depression symptom severity: A prospective cohort study of young adults

Sexual minority individuals have a markedly elevated risk of depression compared to heterosexuals. We examined early threats to social safety and chronically elevated inflammation as mechanisms contributing to this disparity in depression symptoms, and compared the relative strength of the co-occurrence between chronic inflammation and depression symptoms for sexual minorities versus heterosexuals. To do so, we analyzed data from a prospective cohort of sexual minority and heterosexual young adults (n = 595), recruited from a nationally representative sample, that included assessments of early threats to social safety in the form of adverse childhood interpersonal events, three biomarkers of inflammation (i.e., CRP, IL-6, TNF-α) measured at two time points, and depression symptoms over four years. In pre-registered analyses, we found that sexual minorities experienced more adverse childhood interpersonal events, were more likely to display chronically elevated inflammation, and reported more severe depression symptoms than heterosexuals. Adverse childhood interpersonal events and chronically elevated inflammation explained approximately 23 % of the total effect of the association between sexual orientation and depression symptom severity. Further, there was an increased coupling of chronically elevated inflammation and depression symptoms among sexual minorities compared to heterosexuals. These results provide novel longitudinal, population-based evidence for the role of chronically elevated inflammation in linking threats to social safety during childhood with depression symptom severity in young adulthood, consistent with the primary tenets of the social signal transduction theory of depression. Our study extends this theory to the population level by finding that members of a stigmatized population (i.e., sexual minorities) experience a greater risk of depression because of their greater exposure to adverse childhood interpersonal events and the subsequent link to chronic inflammation, highlighting potential biopsychosocial intervention targets.

The influence of early diet quality on the mental health of college students: the mediation effects of height and qi-deficiency

Background

In China, the prevalence of mental health issues among college students is a significant concern in society. This study aims to investigate the impact of early dietary quality on the psychological well-being of college students and elucidate the underlying mechanisms through which these effects occur, specifically focusing on height and qi-deficiency as mediators according to Chinese traditional medicine (CTM).

Methods

A total of 655 college students were surveyed in October 2023 using paper-pencil-based questionnaires at four second-tier universities in Sichuan Province. The assessment included mental health, height, and qi-deficiency. Pearson's correlation and linear regression analyses were employed to examine the mediation model and test the hypotheses.

Results

The college students exhibited acceptable levels of early diet quality (M = 3.72) and mental health (M = 3.63), while also presenting mild qi-deficiency symptoms (M = 2.25). Their average height was measured at 164.61 cm. Early diet quality demonstrated significant associations with mental health (r = 0.38, p < 0.01), height (r = 0.32, p < 0.01), and qi-deficiency (r = -0.32, p < 0.01). Mental health displayed correlations with height (r = 0.32, p < 0.01) and qi-deficiency (r = -0.49, p < 0.01). The results of linear regression analyses revealed significant associations between early diet quality and mental health (β = 0.31, p < 0.01), height (β = 0.21, p < 0.01), as well as qi-deficiency (β = -0.26, p < 0.01). Furthermore, when early diet quality was included in the regression model, both height (β = 0.21, p < 0.01) and qi-deficiency (β = -0.35, p < 0.01) emerged as significant mediators in the relationship with mental health.

Conclusion

The mediation model and hypotheses were strongly supported, demonstrating that early diet quality exerted an influence on the mental health of college students through two distinct pathways: height and qi-deficiency. Moreover, the mediating effect of qi-deficiency was found to be more pronounced than that of height in the relationship between early diet quality and mental health among college students.

Annual Research Review: Neuroimmune network model of depression: a developmental perspective

Depression is a serious public health problem, and adolescence is an 'age of risk' for the onset of Major Depressive Disorder. Recently, we and others have proposed neuroimmune network models that highlight bidirectional communication between the brain and the immune system in both mental and physical health, including depression. These models draw on research indicating that the cellular actors (particularly monocytes) and signaling molecules (particularly cytokines) that orchestrate inflammation in the periphery can directly modulate the structure and function of the brain. In the brain, inflammatory activity heightens sensitivity to threats in the cortico-amygdala circuit, lowers sensitivity to rewards in the cortico-striatal circuit, and alters executive control and emotion regulation in the prefrontal cortex. When dysregulated, and particularly under conditions of chronic stress, inflammation can generate feelings of dysphoria, distress, and anhedonia. This is proposed to initiate unhealthy, self-medicating behaviors (e.g. substance use, poor diet) to manage the dysphoria, which further heighten inflammation. Over time, dysregulation in these brain circuits and the inflammatory response may compound each other to form a positive feedback loop, whereby dysregulation in one organ system exacerbates the other. We and others suggest that this neuroimmune dysregulation is a dynamic joint vulnerability for depression, particularly during adolescence. We have three goals for the present paper. First, we extend neuroimmune network models of mental and physical health to generate a developmental framework of risk for the onset of depression during adolescence. Second, we examine how a neuroimmune network perspective can help explain the high rates of comorbidity between depression and other psychiatric disorders across development, and multimorbidity between depression and stress-related medical illnesses. Finally, we consider how identifying neuroimmune pathways to depression can facilitate a 'next generation' of behavioral and biological interventions that target neuroimmune signaling to treat, and ideally prevent, depression in youth and adolescents.

Chronic social stress in early life can predispose mice to antisocial maltreating behavior

Purpose

In our previous study, we developed an assay system to evaluate antisocial maltreating behavior of conspecific mice using a perpetrator-victim paradigm. We also generated a mouse model for the maltreating behavior by mimicking child maltreatment or abuse. Here, we further investigate the antisocial behavior using anti-aggressive and antipsychotic drugs.

Methods

Model mice sequentially subjected to maternal separation (MS), social defeat (SD), and social isolation (SI) in that order (MS/SD/SI model) were subjected to a maltreating behavioral task. The MS/SD/SI mice were treated with oxytocin (OXY), clozapine (CLZ), haloperidol (HAL), and 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT). Western blotting and enzyme-linked immunosorbent assay were used for protein analysis.

Results

A substantial portion of the MS/SD/SI model mice (46% of males and 40% of females) showed a higher number of nose pokes than the control. OXY or 8-OH-DPAT treatment reduced the high number of nose pokes by the MS/SD/SI mice, whereas HAL increased it. CLZ did not affect the number of nose pokes by the MS/SD/SI mice. Interestingly, although the OXY level in the MS/SD/SI mice was similar to that in the control, the amount of OXY receptor was lower in the MS/SD/SI mice. The amount of 5-HT1A receptor was also decreased in the MS/SD/SI mice.

Conclusion

Chronic social stress in childhood might predispose a mouse to antisocial behavior. Our maltreating behavior assay system, including the MS/SD/SI model, is a good animal system for research on and drug screening for brain disorders associated with antisocial or psychotic behavior.

Sleep Quality as a Critical Pathway Between Adverse Childhood Experiences and Multimorbidity and the Impact of Lifestyle

OBJECTIVES

This study aims to establish the effects of ACEs on multimorbidity through sleep quality and investigate whether lifestyle factors (e.g., eating habits and exercise) may influence this relationship among middle-aged and older adults.

METHODS

Participants were drawn from a cross-sectional sample of community dwelling older adults (N = 276, 55+) and three waves of data from the Midlife in the United States study (MIDUS, N = 843). We examined the direct and indirect effects of ACEs, sleep quality, and health conditions, as well as the conditional effects of physical activity and eating habits.

RESULTS

Across both samples, sleep quality mediated the relationship between ACEs and chronic health conditions. Moderating effects of unhealthy eating and physical activity differed between samples.

DISCUSSION

Sleep quality is an important pathway connecting ACEs and adult multimorbidity, and health behaviors may provide targets for intervention particularly in older adults.

Neurodevelopmental and Neuropsychiatric Disorders

This chapter will focus on microglial involvement in neurodevelopmental and neuropsychiatric disorders, particularly autism spectrum disorder (ASD), schizophrenia and major depressive disorder (MDD). We will describe the neuroimmune risk factors that contribute to the etiopathology of these disorders across the lifespan, including both in early life and adulthood. Microglia, being the resident immune cells of the central nervous system, could play a key role in triggering and determining the outcome of these disorders. This chapter will review preclinical and clinical findings where microglial morphology and function were examined in the contexts of ASD, schizophrenia and MDD. Clinical evidence points out to altered microglial morphology and reactivity, as well as increased expression of pro-inflammatory cytokines, supporting the idea that microglial abnormalities are involved in these disorders. Indeed, animal models for these disorders found altered microglial morphology and homeostatic functions which resulted in behaviours related to these disorders. Additionally, as microglia have emerged as promising therapeutic targets, we will also address in this chapter therapies involving microglial mechanisms for the treatment of neurodevelopmental and neuropsychiatric disorders.

A review of mental health disparities during COVID-19: Evidence, mechanisms, and policy recommendations for promoting societal resilience

Social and economic inequality are chronic stressors that continually erode the mental and physical health of marginalized groups, undermining overall societal resilience. In this comprehensive review, we synthesize evidence of greater increases in mental health symptoms during the COVID-19 pandemic among socially or economically marginalized groups in the United States, including (a) people who are low income or experiencing homelessness, (b) racial and ethnic minorities, (c) women and lesbian, gay, bisexual, transgender, queer, and questioning (LGBTQ+) communities, (d) immigrants and migrants, (e) children and people with a history of childhood adversity, and (f) the socially isolated and lonely. Based on this evidence, we propose that reducing social and economic inequality would promote population mental health and societal resilience to future crises. Specifically, we propose concrete, actionable recommendations for policy, intervention, and practice that would bolster five "pillars" of societal resilience: (1) economic safety and equity, (2) accessible healthcare, including mental health services, (3) combating racial injustice and promoting respect for diversity, equity, and inclusion, (4) child and family protection services, and (5) social cohesion. Although the recent pandemic exposed and accentuated steep inequalities within our society, efforts to rebuild offer the opportunity to re-envision societal resilience and policy to reduce multiple forms of inequality for our collective benefit.

Early life adversities and lifelong health outcomes: A review of the literature on large, social, long-lived nonhuman mammals

Social nonhuman animals are powerful models for studying underlying factors related to lifelong health outcomes following early life adversities (ELAs). ELAs can be linked to lifelong health outcomes depending on the species, system, sensitive developmental periods, and biological pathways. This review focuses on the literature surrounding ELAs and lifelong health outcomes in large, social, relatively long-lived nonhuman mammals including nonhuman primates, canids, hyenas, elephants, ungulates, and cetaceans. These mammals, like humans but unlike the most-studied rodent models, have longer life histories, complex social structures, larger brains, and comparable stress and reproductive physiology. Collectively, these features make them compelling models for comparative aging research. We review studies of caregiver, social, and ecological ELAs, often in tandem, in these mammals. We consider experimental and observational studies and what each has contributed to our knowledge of health across the lifespan. We demonstrate the continued and expanded need for comparative research to inform about the social determinants of health and aging in both humans and nonhuman animals.

Risk and Resilience Measures Related to Psychopathology in Youth

Childhood adversity places youth at risk for multiple negative outcomes. The current study aimed to understand how a constellation of risk and resilience factors influenced mental health outcomes as a function of adversities: socioeconomic status (SES) and traumatic stressful events (TSEs). Specifically, we examined outcomes related to psychosis and mood disorders, as well as global clinical functioning. The current study is a longitudinal follow up of 140 participants from the Philadelphia Neurodevelopmental Cohort (PNC) assessed for adversities at Time 1 (Mean age: 14.11 years) and risk, resilience, and clinical outcomes at Time 2 (mean age: 21.54 years). In the context of TSE, a limited set of predictors emerged as important; a more diverse set of moderators emerged in the context of SES. Across adversities, social support was a unique predictor of psychosis spectrum diagnoses and global functioning; emotion dysregulation was an important predictor for mood diagnoses. The current findings underscore the importance of understanding effects of childhood adversity on maladaptive outcomes within a resilience framework.

Trajectories of depressive symptoms over 20 years and subsequent lower urinary tract symptoms and impact among women

OBJECTIVE

The aim of the study is to examine the association between depressive symptoms and subsequent lower urinary tract symptoms (LUTS) and impact (a composite outcome) among women (N = 1,119) from the Coronary Artery Risk Development in Young Adults study.

METHODS

The Center for Epidemiologic Studies-Depression Scale (CES-D) was administered in 1990-1991 and every 5 years through 2010-2011. In 2012-2013, LUTS and impact data were collected for the first time. Accumulation of risk was examined in the following three ways: (1) mean CES-D score across 20 years (5 observations); (2) depressive symptom trajectory group, determined by group-based trajectory modeling; and (3) intercepts and slopes obtained from women's individual CES-D score trajectories through two-stage mixed effects modeling. For each approach, ordinal logistic regression analyses examined odds of having "greater LUTS/impact" for each unit change in a depressive symptom variable.

RESULTS

(1) With each one-unit increase in mean CES-D score over the 20-year period, women were 9% more likely to report greater LUTS/impact (odds ratio [OR] = 1.09, 95% CI = 1.07-1.11). (2) In comparison with women with consistently low depressive symptoms, women with consistently threshold depression or consistently high depressive symptoms were twice (OR = 2.07, 95% CI = 1.59-2.69) and over five times (OR = 5.55, 95% CI = 3.07-10.06) as likely, respectively, to report greater LUTS/impact. (3) Women's individual symptom intercept and slope interacted. Increases in depressive symptoms across 20 years (greater slopes) were associated with greater LUTS/impact when women's initial CES-D score (intercept) was in the moderate-to-high range relative to the sample.

CONCLUSIONS

Depressive symptoms over 20 years, examined with different degrees of nuance, were consistently associated with subsequently measured LUTS and impact.

Somatovisceral influences on emotional development

Frameworks of emotional development have tended to focus on how environmental factors shape children's emotion understanding. However, individual experiences of emotion represent a complex interplay between both external environmental inputs and internal somatovisceral signaling. Here, we discuss the importance of afferent signals and coordination between central and peripheral mechanisms in affective response processing. We propose that incorporating somatovisceral theories of emotions into frameworks of emotional development can inform how children understand emotions in themselves and others. We highlight promising directions for future research on emotional development incorporating this perspective, namely afferent cardiac processing and interoception, immune activation, physiological synchrony, and social touch.

Is There an Inflammatory Profile of Perinatal Depression?

PURPOSE OF REVIEW

To synthesize and critically examine recent evidence regarding associations between immune system activity and perinatal depression.

RECENT FINDINGS

Despite a significant number of studies assessing potential immunological markers of perinatal depression, it does not appear that levels of any individual pro- or anti-inflammatory marker is a useful predictor of perinatal depression. Some recent studies have observed differences in overall immune system functioning and adaptation across this period, taking into account multiple pro- and anti- inflammatory markers. Furthermore, there is evidence for interactions between depression and maternal psychosocial factors. Immune system functioning may be a mechanism through which social determinants of health contribute to risk for perinatal depression. There is substantial evidence implicating dysregulated immune activity in perinatal depression, yet little clarity regarding a consistent immune profile, especially based on analysis of circulating peripheral cytokines.

Developmental Considerations for Understanding Perceptions and Impacts of Identity-Related Differences: Focusing on Adolescence

Biological psychiatry, similar to many other scientific fields, is grappling with the challenge of revising its practices with an eye toward promoting diversity, equity, and inclusivity. One arena in which much of this work will have significant impact is in developmental science generally and the study of adolescence specifically. Adolescence is a critical period during human development during which important social, neural, and cognitive maturation processes take place. It is also a time marked by risky behaviors and the onset of a range of mental disorders. Social and developmental research has provided insight into the cognitive and neural processes by which perceptions of identity-related differences emerge. Clinical research aimed at understanding how individuals from diverse backgrounds navigate the transition period of adolescence is critical for identifying the unique factors underlying risk and resilience in minoritized populations. Taking a developmental perspective, we review processes by which the brain understands group differences and how the developmental timing of this can influence antecedents of psychological distress. We close with a call to action, pointing to important understudied areas within the field of biological psychiatry that are critical for supporting mental health among diverse adolescent populations.

Chronic social stress during early development is involved in antisocial maltreatment behavior in mice

Purpose

Early-life stress can cause brain inflammation and affect social behavior in adulthood. In humans, maltreated (abused or neglected) children often exhibit antisocial behavior, including violent and sadistic behavior, in adulthood. However, it is unknown whether maltreatment behavior occurs in rodents. Here, we developed an assay system to evaluate conspecific maltreatment behavior in the mouse.

Methods

To assess maltreatment behavior, we devised a two-chamber apparatus separated by a transparent partition, in which one chamber was provided with a nose-poking hole that would trigger foot shocks onto the other. Lidocaine was used to inhibit neural activity in vivo. Brain oscillations were investigated by electroencephalograph. Enzyme-linked immunosorbent assay was used for protein assay. The mouse model was sequentially subjected to maternal separation (MS), social defeat (SD), and social isolation (SI) in that order (MS/SD/SI model).

Results

Inactivation of the anterior cingulate cortex and medial prefrontal cortex increased the level of nose-poking. Maltreatment behavior provoked changes in oxytocin, corticosterone, and brain-derived neurotrophic factor levels. MS/SD/SI mice exhibited more sustained nose-poking behavior during the experiment, resulting in increased foot shocks to the mouse in the opposite chamber. Abnormal brain oscillations were observed in the MS/SD/SI mice.

Conclusion

The MS/SD/SI model and maltreatment-behavior assay may be useful not only to study the relationship between social stress in childhood and antisocial behavior in adulthood, but also for study of etiology, pathology, or treatment for brain disorders, such as psychopathy.

Parent-Child Interaction Therapy Supports Healthy Eating Behavior in Child Welfare-Involved Children

OBJECTIVE

We tested the efficacy of standard Parent-Child Interaction Therapy (PCIT), a live-coached, behavioral parent-training program, for modifying problematic eating behaviors in a larger effectiveness trial of PCIT for children involved in the child welfare system.

METHOD

Children ages 3-7 years and their parents were randomly assigned to PCIT intervention (n = 120) or services as the usual control (SAU; n = 84) groups in a randomized clinical trial. Children's eating behaviors were assessed pre- and post-intervention via the Child Eating Behaviors Questionnaire (CEBQ). Intention-to-treat analyses were conducted, followed by per-protocol analyses, on treatment-engaging families only.

RESULTS

PCIT led to reductions in child welfare-involved children's food responsiveness, speed of food consumption, and tendency to engage in emotional overeating relative to children in the services-as-usual control condition. Standard PCIT may be an effective intervention to promote healthy child eating behaviors in families involved with child welfare, even when food-related behaviors are not directly targeted by the intervention. Public Health Significance: This clinical trial provides evidence that child welfare-involved children who received PCIT experienced significant reductions in maladaptive eating-related behaviors, namely food responsiveness, emotional overeating, and speed of eating. These findings were observed in relation to children in a comparison control group who had access to child welfare services-as-usual.

Bidirectional prediction between weight status and executive function in children and adolescents: A systematic review and meta-analysis of longitudinal studies

This study examined the predictability of child weight status on executive function (EF) and vice versa. We searched PubMed, CINAHL, Web of Science, and EMBASE for longitudinal studies conducted in children and adolescents on October 31, 2021. A pairwise meta-analysis was performed using a frequentist random-effects approach. The quality of all included studies was evaluated using Newcastle-Ottawa Scale and GRADE assessments. This study included 18 longitudinal studies (N = 30,101). Overall executive functioning was a significant negative predictor of child weight status (pooled beta coefficient = -0.14; 95% confidence interval [CI] [-0.22 to -0.07]; I²  = 97%). The pooled odds ratio also revealed that high EF children had a significant lower risk for developing overweight/obesity (odds ratio [OR] = 0.72; 95% CI [0.59 to 0.87]; I²  = 72%). Conversely, child weight status was a significant negative predictor of overall executive functioning (pooled beta coefficient = -0.06; 95% CI [-0.12 to -0.01]; I²  = 81%). These results suggest a bidirectional prediction between child weight status and EF. These predictabilities are low but potentially beneficial for implementation in childcare systems.

Multi-sample assessment of stress reactivity as a mediator between childhood adversity and mid- to late-life outcomes

OBJECTIVES

We examined whether adult stress reactivity accounts for the relationship between early life adversity (ELA) and psychological, physical, and cognitive outcomes.

METHODS

We examined the relationship between ELA, stress reactivity, psychological well-being, physical health, and cognitive function in two separate datasets - a cross-sectional community sample of older adults (N = 510) aged 60 and older, and waves I-III of the Midlife in the United States (MIDUS) dataset. Age, sex, and income served as covariates in all analyses. Bootstrapped mediation models were used to assess recent stress as a mediator between ELA and mid- to late-life outcomes.

RESULTS

ELA was significantly associated with adult stress, anxiety, depression, health conditions, and object cognitive assessments. Adult stress partially accounted for the relationships between ELA and depression, anxiety, health conditions, and memory problems.

CONCLUSION

Our findings demonstrate that ELA may influence increased stress in older age, which confers additional risks for developing depression, anxiety, health problems, and cognitive decline. It is possible that intervening on adult stress may reduce risk for both psychological and physical pathology across the lifespan. Further research is needed to develop targeted interventions for mid and late-life stress to improve overall health as individuals age.

Lack of Evidence for a Relationship Between Salivary CRP and Women's Sexual Desire: An Investigation Across Clinical and Healthy Samples

BACKGROUND

Inflammation has been linked to a variety of mental and physical health outcomes that disproportionately impact women, and which can impair sexual function; thus, there is reason to expect a link between inflammation and women's sexual functioning.

AIM

To test the hypothesis that higher concentrations of C-reactive protein (CRP), a general biomarker of inflammation, would predict women's lower sexual desire.

METHOD

As 2 independent research teams, we conducted 3 separate studies (total n = 405) that assessed salivary CRP and various measurements of sexual desire in different women populations.

OUTCOMES

Female Sexual Function Index, Sexual Desire Inventory-2, Decreased Sexual Desire Screener, and Sexual Interest and Desire Inventory.

RESULTS

Regardless of the way sexual desire was measured (e.g., state vs trait; general desire vs. desire functioning) and the population sampled (i.e., healthy vs. clinically diagnosed with sexual dysfunction), all the studies revealed null results.

CLINICAL IMPLICATIONS

While exploratory, the convergence of these null results across studies and researchers suggests that if there is an association between inflammation and women's sexual desire, it is likely very subtle.

STRENGTHS & LIMITATIONS

Across 2 independent research teams, 3 unrelated studies, and various measurements of sexual desire, results were consistent. These points lend to the generalizability of the results. However, study designs were cross-sectional.

CONCLUSIONS

Future research may reveal (i) a non-linear threshold effect, such that inflammation does not begin to impact women's sexual desire until it is at a high level, (ii) inflammatory biomarkers other than CRP might be more sensitive in detecting associations between inflammation and desire, should they exist, or (iii) the mechanisms underlying sexual dysfunction may differ between sexes. Clephane K, et al. Lack of Evidence for a Relationship Between Salivary CRP and Women's Sexual Desire: An Investigation Across Clinical and Healthy Samples. J Sex Med 2022;19:745-760.

The cholinergic anti-inflammatory pathway in humans: State-of-the-art review and future directions

The parasympathetic nervous system modulates inflammation through efferent vagus nerve signaling. Tracey (2002) termed this process as the cholinergic anti-inflammatory pathway (CAP). Interest in the potential practical use of this immune-modulatory process is increasing alongside increasing appreciation for the role of systemic inflammation in the etiology of somatic and psychological disease. A diverse literature exists providing expansive correlational evidence and some preliminary experimental evidence of the CAP in humans. However, so far this literature has not been well integrated and critically evaluated. This review describes the current state-of-the-art of research into vagus nerve driven parasympathetic control of inflammation in humans. Substantial limitations and gaps in the literature are identified, and promising directions for future research are highlighted.

Limitations of the protective measure theory in explaining the role of childhood sexual abuse in eating disorders, addictions, and obesity: an updated model with emphasis on biological embedding

In addition to its immediate negative consequences, childhood sexual abuse is associated with lifelong deleterious mental and physical health outcomes. This review employs a biopsychosocial perspective to better understand pathways from childhood sexual abuse to eating disorders, food and drug addictions, and obesity across the life course. Guided by an updated conceptual model, this review delineates how the biological embedding of childhood sexual abuse triggers a cascade of interrelated conditions that often result in failed attempts at weight suppression and eventually obesity. Such biological embedding involves pathways such as inflammation, allostatic load, reward sensitivity, activation of the hypothalamic-pituitary-adrenal axis, epigenetics, and structural and functional changes in the brain. These pathways are in turn theorized to lead to food addiction, substance use disorder, and eating disorders-each with potential pathways toward obesity over time. Predisposing factors to childhood sexual abuse including gender, culture, and age are discussed. This model calls into question the longstanding "protective measure" theory that purports individuals exposed to sexual abuse will deliberately or subconsciously gain weight in attempt to prevent future victimization. A more comprehensive understanding of the mechanisms by which childhood sexual abuse becomes biologically embedded may help clinicians and survivors normalize and/or address disordered eating and weight-related outcomes, as well as identify intervention strategies.Level of evidence: Level V: opinions of respected authorities, based on descriptive studies, narrative reviews, clinical experience, or reports of expert committees.

Respiratory Sinus Arrhythmia as a Physiological Resilience Marker for Children's Health

OBJECTIVE

The current study aimed to test parasympathetic nervous system activity, indexed through resting respiratory sinus arrhythmia (RSA) as a resilience factor that moderates the associations between socioeconomic status (SES), circulating cytokines, and somatic health in children.

METHODS

The sample included 181 parent-child dyads (mean [standard deviation] child age = 9.91 [0.57] years; 50.3% boys). Parents reported on family income, parental education, and subjective social status, to index SES. Children provided serum samples for assaying circulating inflammatory cytokines and had RSA measured during a 5-minute seated resting period. We used a composite measure of inflammation that combined standardized measures of interleukin 6, interleukin 10, and tumor necrosis factor α. Parents reported on their child's global health impairment and number of chronic health conditions.

RESULTS

Lower SES was associated with poorer global health, and higher levels of inflammation were associated with poorer global health, but these associations were not significant among children with high resting RSA. Specifically, resting RSA moderated the association between SES and global health impairment (B = 0.09, standard error [SE] = 0.02, p < .001). Preliminary evidence suggests that resting RSA may also moderate the association between inflammation and global health impairment (B = -0.12, SE = 0.03, p < .001), although this effect was no longer significant after Winsorizing an outlier value of a child with high global health impairment (B = -0.06, SE = 0.03, p = .04).

CONCLUSIONS

High resting RSA may represent a physiological profile of resilience in children, weakening the associations between low SES and poor somatic health, and between greater inflammation and poor somatic health.

Emotion Regulation as a Pathway Connecting Early Life Adversity and Inflammation in Adulthood: a Conceptual Framework

Chronic inflammation is implicated in a variety of diseases (e.g., cardiovascular disease and cancer). Much evidence suggests that early life adversity (ELA), such as maltreatment or neglect, can increase risk for inflammation in adulthood. ELA may program proinflammatory activity via its effects on brain areas involved in emotion regulation. Of multiple emotion regulation strategies, some are considered maladaptive (e.g., expressive suppression), while others are generally adaptive (e.g., cognitive reappraisal). We propose a conceptual framework for how emotion regulation tendencies may affect vulnerability or resilience to inflammation in adults who experienced adversity in childhood and/or adolescence. In support of this framework, we summarize evidence for the relationships between emotion dysregulation and higher inflammation (i.e., vulnerability), as well as between cognitive reappraisal and lower inflammation (i.e., resilience), in healthy adults with a history of ELA. Plausible neurobiological, physiological, psychosocial, and ELA-specific factors, as well as interventions, contributing to these associations are discussed. Strengths and limitations of the extant research, in addition to ideas for future directions, are presented.

Factors associated with peritraumatic stress symptoms among the frontline healthcare workers during the outbreak of COVID-19 in China

OBJECTIVES

This study aimed to examine the prevalence of peritraumatic stress symptoms (PTSSs), perceived threat, social support and factors contributing to clinically significant PTSS among frontline COVID-19 healthcare workers (HCWs) in China.

DESIGN AND SETTING

An online survey through self-administered questionnaires was conducted from 18 February to 4 March 2020, during the outbreak of COVID-19.

OUTCOMES MEASURES

PTSS was assessed using the post-traumatic stress disorder (PTSD) self-rating scale. Demographic and socioeconomic characteristics, self-reported health, physical/psychological symptoms, perceived threat from frontline work and perceived social support were investigated. Multivariable line regression analysis distinguished factors associated with HCWs' PTSS scores.

RESULTS

A total of 676 (58.1%) HCWs have shown clinically significant high levels of PTSS. Only 441 (37.9%) self-reported good health. Most had physical symptom(s) (915 (78.7%)), psychological symptom(s) (906 (77.9%)), inability to vent emotions (284 (24.4%)), emotional exhaustion (666 (57.3%)) and 1037 (89.2%) needed professional respect. Moreover, social support received was less than expected, and the receipt of psychological services/help scored the lowest (3.11±1.73). Combined psychological and physical symptoms, difficulty in releasing tension and venting emotions timely, fear of infection, emotional exhaustion and depersonalisation are significantly associated with PTSS scores among frontline HCWs. Working ≥8 hours, having the senior professional title, self-reported health, enjoying perfect protection and control measures, economic subsidy and control policy on reducing discriminatory practices are negatively correlated with PTSS scores.

CONCLUSIONS

During the outbreak of COVID-19, frontline HCWs experienced clinically significant high levels of PTSS and heavy workload, and the emergency resulted in their inadequate psychosocial support. If this is left unchecked, HCWs have a higher risk of developing PTSD. Early detection, identification and person-directed, targeted multidisciplinary interventions should be undertaken to address various influencing factors. Comprehensive measures, including setting up emotional release channels, as well as providing psychological and social support intervention for HCWs globally, are highly recommended.

Pancreatic HB9 protein level is affected by early life stress in young adult rats: possible involvement of TNF-α and corticosterone

This study examined foot shock stress effects, during weaning, on pancreatic HB9 protein expression in young adult male rats in the presence or absence of adulthood stress. The pups were divided into Control, Early life stress, Young adult stress, and Early + young adult stress groups. Plasma corticosterone, insulin, glucose, and TNF-α concentrations, and pancreatic HB9 protein expression were assessed. At 2 weeks of age, stress increased plasma corticosterone level. During young adulthood, plasma TNF-α and glucose concentrations increased, whereas plasma insulin and pancreatic HB9 protein levels decreased in Early life stress group. Whereas, Early + young adulthood stress group showed no change in the study parameters, except for plasma corticosterone and insulin concentrations. Overall, early life stress reduced pancreatic HB9 protein expression possibly by elevating plasma corticosterone and TNF-α levels in early life and adulthood, respectively. However, combined with adulthood stress, HB9 protein expression increased to the level of Control.

Biobehavioral organization shapes the immune epigenome in infant rhesus Macaques (Macaca mulatta)

How individuals respond to and cope with stress is linked with their health and well-being. It is presumed that early stress responsiveness helps shape the health of the developing organism, but the relationship between stress responsiveness and early immune function during development is not well-known. We hypothesized that stress responsiveness may shape epigenetic regulation of immune genes in infancy. We investigated whether aspects of behavioral responsiveness and hypothalamic-pituitary adrenal stress-response were associated with epigenome-wide immune cell DNA methylation patterns in 154 infant rhesus monkeys (3-4 months old). Infants' behavioral and physiological responses were collected during a standardized biobehavioral assessment, which included temporary relocation and separation from their mother and social group. Genome-wide DNA methylation was quantified using restricted representation bisulfite sequencing (RRBS) from blood DNA collected 2-hours post-separation. Epigenome-wide analyses were conducted using simple regression, multiple regression controlling for immune cell counts, and permutation regression, all corrected for false discovery rate. Across the variables analyzed, there were 20,368 unique sites (in 9,040 genes) at which methylation was significantly associated with at least one behavioral responsiveness or cortisol measure across the three analyses. There were significant associations in 442 genes in the Immune System Process ontology category, and 94 genes in the Inflammation mediated by chemokine and cytokine signaling gene pathway. Out of 35 candidate genes that were selected for further investigation, there were 13 genes with at least one site at which methylation was significantly associated with behavioral responsiveness or cortisol, including two intron sites in the glucocorticoid receptor gene, at which methylation was negatively correlated with emotional behavior the day following the social separation (Day 2 Emotionality; β = -0.39, q < 0.001) and cortisol response following a relocation stressor (Sample 1; β = -0.33, q < 0.001). We conclude that biobehavioral stress responsiveness may correlate with the developing epigenome, and that DNA methylation of immune cells may be a mechanism by which patterns of stress response affect health and immune functioning.

Heart Rate Variability and Circulating Inflammatory Markers in Midlife

Theoretical perspectives and empirical evidence suggest that the parasympathetic nervous system engages in active monitoring and moderating of inflammatory processes. A clearer understanding of the bidirectional communication between the parasympathetic nervous system and the immune system could lead to novel clinical interventions for inflammatory illnesses. The current study used a large (N ​= ​836) nationally representative sample of adults in the United States to investigate the associations between resting parasympathetic modulation of the heart, indexed through both high frequency heart rate variability (HF-HRV) and low frequency heart rate variability (LF-HRV), and six circulating markers of inflammation. Statistical analyses revealed robust inverse associations of HF-HRV with interleukin-6 (IL6), C-reactive protein (CRP), and fibrinogen, with or without covariate adjustment. Similar inverse associations were observed between LF-HRV and IL6 and CRP. No significant associations were observed between HRV and either inflammatory adhesion molecules (E-selectin, intracellular adhesion molecule-1) or soluble IL6 receptor. Results are consistent with the cholinergic anti-inflammatory pathway and suggest that parasympathetic modulation of inflammation through the vagus nerve may act on specific inflammatory molecules more than others.

Integrating anthropometric and cardiometabolic health methods in stress, early experiences, and development (SEED) science

Within Stress, Early Experiences, and Development (SEED) science, there is a growing body of research demonstrating complex associations not only between stress, development, and psychopathology, but also with chronic disease risk factors. We argue that it is important for SEED researchers to consider including child anthropometric and physical health measures to more comprehensively capture processes of risk and resilience. Broader adoption of harmonized anthropometry and health measures in SEED research will facilitate collaborations, yielding larger datasets for research in high-risk populations, and greater opportunity to replicate existing findings. In this review, we identify optimal anthropometric and cardiometabolic health measurement methods used from infancy through adolescence, including those that are low-burden and inexpensive. Methods covered include: waist, hip, and head circumference, height, length, weight, pubertal development, body composition, blood pressure, arterial stiffness, carotid intima media thickness, and serum measures of cardiometabolic risk and inflammation. We provide resources for SEED researchers to integrate these methods into projects or to better understand these methods when reading the literature as well as where to find collaborators for more in-depth studies incorporating these measures. With broader integration of psychological and physical health measures in SEED research, we can better inform theory and interventions to promote health and resilience in individuals who have experienced early stress.

The intergenerational interplay of adversity on salivary inflammation in young children and caregivers

Systemic inflammation links exposure to early childhood adversity to later disease. The associations among adversity and disease risk might in part operate through poor oral hygiene and subsequent periodontal inflammation, which can be measured in saliva. Few studies, however, have examined the association between adversity and salivary inflammation in young children. Further, there is a dearth of literature investigating adverse experiences and salivary inflammation in children and caregivers together, limiting our understanding of the intergenerational, dual effects of adversity on inflammation for both members of the caregiver-child dyad. This study tested child and caregiver adversity and their associations with an inflammatory composite (i.e., IL-6, IL-1β, IL-8, TNF-α) and CRP in 93 preschool-age children and their caregivers. Caregivers reported on their child's experiences of adversity, as well as on their own adverse experiences, using a comprehensive questionnaire synthesized from previous checklists for complete coverage of possible adverse events. Results showed that caregivers' salivary inflammatory markers (i.e., IL-6, IL-1β, IL-8, TNF-α, and CRP) were not significantly correlated with the same five inflammatory markers in children's saliva. Among children, adversity was associated with significantly higher levels of the inflammatory composite, though not CRP. This association was amplified among children whose caregivers also experienced more adversity during adulthood. Among caregivers, childhood adversity and adulthood adversity were each independently associated with significantly higher levels of the inflammatory composite and CRP. The association between caregivers' own childhood adversity and inflammation was amplified among caregivers whose children also experienced more adversity during their childhoods. These findings provide preliminary evidence for the possible dual role of young children's and caregivers' adverse experiences in contributing to salivary inflammation for both members of the dyad, suggesting possible implications for systemic inflammation and future disease.

Prenatal and childhood stress exposure and the sex specific response to psychosocial stress in adulthood

BACKGROUND

Early life stress exposures may cause dysregulation of the Hypothalamic Pituitary Adrenal (HPA)-axis and cortisol production, with timing and sex-specific effects. Studies examining the impact of early life stress on cortisol responses to stress have focused on severe trauma and have produced inconsistent results. The aim of this study was to investigate whether common early life stressors, experienced prenatally or throughout childhood and adolescence, play a role in the dysregulation of the HPA-axis in early adulthood.

METHODS

Exposures to common life stress events were examined prenatally and as longitudinal trajectories of stress exposure from birth to age 17 in males and females from Gen2 of the Raine Study. At age 18 years, 986 participants were assessed for their salivary cortisol response to a psychosocial stressor - the Trier Social Stress Test (TSST).

RESULTS

In males there was an association between high prenatal stress exposure at 18 weeks gestation and a heightened TSST response. We found evidence for sex-specific associations with increasing stress exposure during adolescence (the ascending trajectory) whereby males were more likely to be non-responders to the TSST and females were more likely to be responders.

CONCLUSION

Our results point to sex differences in how stress exposure in-utero and exposure increasing during adolescence may affect regulation of the HPA-axis later in life. However, overall common life stress events experienced in-utero, during childhood and adolescence show limited impact on the HPA-axis stress response in early adulthood.

Functional Alterations and Cerebral Variations in Humans Exposed to Early Life Stress

Early life stress can be caused by acute or chronic exposure to childhood events, such as emotional, physical, sexual abuse, and neglect. Early stress is associated with subsequent alterations in physical and mental health, which can extend into adolescence, adulthood, and even old age. The effects of early stress exposure include alterations in cognitive, neuropsychological, and behavioral functions, and can even lead to the development of psychiatric disorders and changes in brain anatomy. The present manuscript provides a review of the main findings on these effects reported in the scientific literature in recent decades. Early life stress is associated with the presence of psychiatric disorders, mainly mood disorders such as depression and risk of suicide, as well as with the presence of post-traumatic stress disorder. At the neuropsychological level, the involvement of different mental processes such as executive functions, abstract reasoning, certain memory modalities, and poor school-skill performance has been reported. In addition, we identified reports of alterations of different subdomains of each of these processes. Regarding neuroanatomical effects, the involvement of cortical regions, subcortical nuclei, and the subcortical white matter has been documented. Among the telencephalic regions most affected and studied are the prefrontal cortex, the hippocampus, the amygdala, and the anterior cingulate cortex. Understanding the impact of early life stress on postnatal brain development is very important for the orientation of therapeutic intervention programs and could help in the formulation and implementation of preventive measures as well as in the reorientation of research targets.

Adiposity, Inflammation, and Working Memory: Evidence for a Vicious Cycle

Overweight and obesity constitute the fifth leading cause of preventable deaths worldwide. One pathway through which excess weight contributes to poor health outcomes is via inflammatory activity and changes in cognitive processes. Prior theory has proposed a vicious cycle whereby obesity potentiates inflammatory activity, which alters cognitive processes such as working memory, which in turn leads to a reduced ability to self-regulate and therefore manage weight. However, to date no longitudinal studies have examined this potential dynamic. In the current study, we addressed this gap by assessing the relations among fat mass, C-reactive protein (CRP), and working memory across time in a large sample of 8536 children followed through adolescence in the Avon Longitudinal Study of Parents and Children in the United Kingdom. Adiposity was quantified via dual emission x-ray absorptiometry (DEXA) at ages 9 and 15.5 years old, and inflammatory activity was indexed via circulating serum C-reactive protein (CRP) levels assessed with a high-sensitivity assay at those same ages. Working memory was assessed between these two time points, at age 10, permitting examination of the temporal relations between working memory, adiposity, and inflammatory activity. As hypothesized, we found that fat mass predicted later poor working memory, and this association was statistically mediated by CRP. Further, we found that poor working memory predicted greater subsequent fat mass and CRP, and the link between working memory and subsequent CRP was partially mediated by fat mass. These results thus could be taken to suggest the existence of a vicious cycle of mutually amplifying adiposity, inflammatory activity, and poor working memory over time.

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Adiposity and inflammatory activity (CRP) was measured at ages 9 and 15.5 ​yrs.

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Working memory was assessed at age 10 ​yrs.

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Adiposity predicted working memory, and this association was mediated by CRP.

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Working memory predicted later adiposity and CRP, this was mediated by adiposity.

Food Addiction and Psychosocial Adversity: Biological Embedding, Contextual Factors, and Public Health Implications

The role of stress, trauma, and adversity particularly early in life has been identified as a contributing factor in both drug and food addictions. While links between traumatic stress and substance use disorders are well documented, the pathways to food addiction and obesity are less established. This review focuses on psychosocial and neurobiological factors that may increase risk for addiction-like behaviors and ultimately increase BMI over the lifespan. Early childhood and adolescent adversity can induce long-lasting alterations in the glucocorticoid and dopamine systems that lead to increased addiction vulnerability later in life. Allostatic load, the hypothalamic-pituitary-adrenal axis, and emerging data on epigenetics in the context of biological embedding are highlighted. A conceptual model for food addiction is proposed, which integrates data on the biological embedding of adversity as well as upstream psychological, social, and environmental factors. Dietary restraint as a feature of disordered eating is discussed as an important contextual factor related to food addiction. Discussion of various public health and policy considerations are based on the concept that improved knowledge of biopsychosocial mechanisms contributing to food addiction may decrease stigma associated with obesity and disordered eating behavior.

Early life maltreatment and resting-state heart rate variability: A systematic review and meta-analysis

Recent focus on the consequences of early life adversity (ELA) in neurobiological research led to a variety of findings suggesting alterations in several physiological systems, such as the cardiovascular system. In this systematic review and meta-analysis, we focused on the relationship between early life maltreatment (ELM), one form of ELA, and resting vagal activity indexed by resting-state heart rate variability (HRV). A systematic search of the literature yielded 1'264 hits, of which 32 studies reporting data for group comparisons or correlations were included. By quantitative synthesis of existing studies using random-effect models, we found no evidence for a relationship between ELM exposure and resting vagal activity in principal. Conducting meta-regression analyses, however, we found the relationship between ELM and resting vagal activity to significantly vary as a function of both age and the presence of psychopathology. In light of the current multitude of vastly unclear pathways linking ELM to the onset of disease, we emphasize the need for further research and outline several aspects to consider in future studies.

Prenatal and childhood adversity and inflammation in children: A population-based longitudinal study

BACKGROUND

Stressful life events experienced during childhood and early prenatal development have been associated with inflammation during childhood. However, no study has considered these two exposures jointly, or has investigated the effect of their interaction.

METHODS

In the Avon Longitudinal Study of Parents and Children, a general-population birth cohort, we explored if inflammatory markers [serum C-reactive protein (CRP) and interleukin 6 (IL-6)] at age 9 years were related to early prenatal events (at 18 weeks pregnancy), childhood events (measured on seven occasions at ages 0-9 years) and their interaction (n = 3,915). Latent growth curve modelling estimated trajectories of childhood events, and linear regression explored associations of prenatal and childhood events with inflammatory markers. Models controlled for ethnicity, socioeconomic status and body mass index, were stratified by gender and considered both unweighted and weighted (by impact) event exposures.

RESULTS

Even after adjustment for confounders and prenatal events, both the intercept and the slope of number of childhood events were associated with IL-6, but only in females. The significant effect of the slope held for both weighted (by impact) and unweighted event specifications. Prenatal events were not associated with either inflammatory marker when childhood events were controlled. There was no evidence for synergistic effects of prenatal and childhood events.

CONCLUSION

Independently of prenatal adverse life events, the number and increase in number of adverse life events experienced in childhood were associated positively with plasma levels of inflammatory markers, such as IL-6, in girls. This gender specificity warrants further research.

Future Directions in Peer Relations Research

Peer relationships among youth have been examined as predictors of mental health outcomes for at least fifty years, revealing dozens of discrete peer constructs that each are associated with adjustment in childhood, adolescence, and later in adulthood. Future research may benefit by examining a range of new outcomes and psychological processes that have been discussed recently in related literatures. This paper reviews recent research on interpersonal determinants of physical health outcomes, and opportunities for greater examination of 1) peer influence processes toward health risk behaviors; 2) neural correlates of peer adversity; 3) adverse peer experiences that may affect physiological markers of stress response; and 4) immune system markers of peer adversity. Additional future directions include the study of differences in the forms and functions of peer interactions within the digital age.

The Psychobiology of Bereavement and Health: A Conceptual Review From the Perspective of Social Signal Transduction Theory of Depression

Losing a spouse is considered one of the most stressful life events a person can experience. Particularly in the immediate weeks and months after the loss, bereavement is associated with a significantly increased risk of morbidity and mortality. Despite an abundance of research aimed at identifying risk factors for adverse health outcomes following marital death, the mechanisms through which mental and physical health problems emerge following bereavement remain poorly understood. To address this issue, the present review examines several pathways that may link bereavement and health, including inflammation and immune dysregulation, genetic and epigenetic changes, gut microbiota activity, and biological aging. We then describe how these processes may be viewed from the perspective of the Social Signal Transduction Theory of Depression to provide a novel framework for understanding individual differences in long-term trajectories of adjustment to interpersonal loss. Finally, we discuss several avenues for future research on psychobiological mechanisms linking bereavement with mental and physical health outcomes.

Adverse childhood experiences and biomarkers of inflammation in a diverse cohort of early school-aged children

Objective

The objective of this study was to evaluate the relationship between ACEs and inflammatory profiles (i.e., pro- and anti-) in early childhood and to examine whether patterns differ for racial/ethnic subgroups.

Study design

Using longitudinal data from the Multidimensional Assessment of Preschoolers Study (MAPS) (N = 122), we examined the relationship between adverse childhood experiences (ACEs) beginning at birth, C -reactive protein (CRP), and both pro-inflammatory (i.e., IL-1 β, IL-6, TNF, and CRP) and anti-inflammatory (i.e. IL-4 and IL-10) biomarkers during early school age (ages 6-8 years).

Results

No children in the sample were reported to have experienced 0 ACES, 7% had 1 ACE, 51% had 2-3 ACEs, and 42% had 4 or more ACEs accumulated by the early school-age wave (ESA). There were no significant associations between cumulative ACEs and inflammatory markers. However, parental substance abuse, a specific ACE, was positively correlated with a pro-inflammatory profile at early school age (r = 0.18, p<.05). Specifically, substance abuse as an ACE was associated with higher levels of pro-inflammatory markers such as IL-1 β and IL-6. Additionally, Hispanics with ACEs had higher levels of CRP than Black and white individuals.

Conclusions

Children with histories of ACEs, especially those with parental substance abuse, may have higher levels of inflammation. Better understanding the role of inflammation in the development of chronic diseases for individuals with ACEs may allow earlier identification and prevention of disease during childhood for those at the highest risk.

Interferon-beta-induced changes in neuroimaging phenotypes of appetitive motivation and reactivity to emotional salience

Treatment with interferon (IFN) has been associated with depressive side effects. Previous neuroimaging studies have provided information about changes in brain activation patterns in patients under treatment with IFN-alpha, but the effect of other IFNs, or the role of the underlying disease, has yet to be clarified. In the present fMRI study, we looked at brain changes after 8 days of IFN-beta treatment in N = =17 healthy volunteers, thus avoiding the possible confound of the effects of underlying pathology in studies of IFN-treated patients with neurological or other medical disorders. We followed a symptom dimensional approach by simultaneously investigating two distinct symptom domains of depressiveness: negative affect (amygdala) and appetitive motivation (ventral striatum). In these early phases of IFN treatment we detected a selective change in neural substrates of appetitive motivation, consistent with the predominant symptomatic change recorded in psychopathology ratings. In contrast, the fMRI phenotype of negative affect, which is known to characterize disorders of affect involving anxiety and depressiveness as well as individual vulnerability to depression, was unchanged after treatment. These findings suggest that IFN may induce an affective syndrome through a mechanism involving down-regulation of appetitive motivation.

Retrospectively reported childhood physical abuse, systemic inflammation, and resting corticolimbic connectivity in midlife adults

Childhood abuse confers risk for psychopathology and pathophysiology in midlife through intermediate pathways that remain unclear. Systemic inflammation was tested in the present study as one pathway that may link physical abuse in childhood to the adult functioning of corticolimbic brain circuits broadly implicated in risk for poor mental and physical health. Midlife adults (N = 303; 30-51 years of age; 149 women) without psychiatric, immune, or cardiovascular diagnoses provided retrospective reports of childhood physical abuse. Functional connectivity between corticolimbic brain areas (amygdala, hippocampus, ventromedial prefrontal cortex [vmPFC], anterior cingulate cortex [ACC]) was measured at rest using functional magnetic resonance imaging. Circulating levels of interleukin(IL)-6, a pro-inflammatory cytokine previously linked to childhood abuse and corticolimbic functionality, were measured via blood draw. Consistent with prior studies, retrospectively reported childhood physical abuse was associated positively with circulating IL-6, and negatively with connectivity between the amygdala and vmPFC. IL-6 was also associated negatively with several corticolimbic functional connections, including amygdala-vmPFC connectivity. Moreover, path analyses revealed an indirect effect of IL-6 that partially explained the association between childhood physical abuse and adult amygdala-vmPFC connectivity. Consistent with recent neurobiological models of early life influences on disease risk across the lifespan, associations between childhood physical abuse and adulthood corticolimbic circuit functionality may be partially explained by inflammatory processes.

Adverse childhood experiences and neuroinflammatory biomarkers-The role of sex

Despite the growing interest in adverse childhood experiences and biomarkers, less attention has been paid to multiple biomarkers as representing interrelated systems among college students. Guided by the neuroinflammatory pathway hypothesis, the current project takes the initial step in examining the link between three types of childhood adversity and biomarkers of neuroplasticity (brain-derived neurotropic factor [BDNF]) and low-grade inflammation (C-reactive protein [CRP]) in an overarching model and whether this link may differ in men and women. Undergraduate students (n = 85) were recruited through multiple departments from a state university. The participants responded to the detailed online survey questionnaire on childhood adversity and provided one blood sample via venous blood draw. Given that CRP and BDNF represent two interrelated systems, structural equation models were considered the most suitable for the analyses. The findings partially support neural and inflammatory pathways, such that childhood adversity and particularly family dysfunction have a significant positive effect on BDNF (b = 30.41, p < .01). The link between family dysfunction and CRP was stronger in female students (b = 0.57, p < .05). Results suggest that interventions for college students with family dysfunctions may need to target different physiological and behavioral outcomes for male and female students.

The “systems approach” to treating the brain: opportunities in developmental psychopharmacology

The significance of early life for the long-term programming of mental health is increasingly being recognized. However, most psychotropic medications are currently intended for adult patients, and early psychopharmacological approaches aimed at reverting aberrant neurodevelopmental trajectories are missing. Psychopharmacologic intervention at an early age faces the challenge of operating in a highly plastic system and requires a comprehensive knowledge of neurodevelopmental mechanisms. Recently the systems biology approach has contributed to the understanding of neuroplasticity mechanisms from a new perspective that interprets them as the result of complex and dynamic networks of signals from different systems. This approach is creating opportunities for developmental psychopharmacology, suggesting novel targets that can modulate the course of development by interfering with neuroplasticity at an early age. We will discuss two interconnected systems—the immune and gut microbiota—that regulate neurodevelopment and that have been implicated in preclinical research as new targets in the prevention of aberrant brain development.


Transdiagnostic neural correlates of volitional emotion regulation in anxiety and depression

BACKGROUND

Individuals who suffer from anxiety and/or depression face difficulty in adaptively managing emotional responses, while accumulating evidence suggests impaired emotion regulation is a transdiagnostic feature of psychopathology. Effectual regulation in the context of negative stimuli is characterized by engagement of the prefrontal cortex (PFC) coupled with reduced amygdala reactivity. In anxiety disorders and major depression, PFC underengagement and atypical PFC-amygdala connectivity has been observed, although patient findings based on case-control studies have been mixed with regard to magnitude, locality, and extent of dysfunction. As anxiety disorders and major depression are heterogeneous disorders and frequently comorbid with one another, delineating relationships between reappraise-related substrates and symptoms may advance our understanding of emotion dysregulation in these populations.

METHODS

We examined PFC activation and its functional connectivity (FC) to the amygdala using functional magnetic resonance imaging in a large sample of patients (N = 174) with primary generalized anxiety disorder (n = 47), social anxiety disorder (n = 78), or major depressive disorder (n = 49) during a reappraisal-based emotion regulation task. Comorbidity was permitted and the majority of participants had a concurrent psychiatric illnesses.

RESULTS

Across participants, whole-brain results showed that (1) greater anxiety and depression symptom severity was related to less engagement of the dorsal anterior cingulate cortex (ACC) and (2) less FC between the amygdala and ventrolateral PFC. Results were driven by anxiety, while depression symptoms were not significant.

CONCLUSION

These findings demonstrate that individual differences in anxiety and depression may help explain ACC and PFC dysfunction during emotion regulation observed across anxiety and depressive disorders.

Emotion dysregulation: A theme in search of definition

Emotion dysregulation is defined as patterns of emotional experience or expression that interfere with goal-directed activity. This paper considers this functionalist definition from a developmental perspective with the goal of elaborating this approach with respect to its central questions. What are the goals that are impeded by emotionally dysregulated responding, and what alternative goals might motivate emotion dysregulation? What are the developmental processes by which these goals take shape, and what are the influences of the family context, and especially of central relationships in the family, in their emergence? How does this functionalist account address the complex interaction of experience and developing biological processes that also influence emotion regulation and dysregulation? Drawing on research literature concerning children at risk for affective psychopathology and considering relevant examples of the interaction of biology and context, this discussion offers a portrayal of emotion dysregulation as a biologically dynamic, experience-based aspect of adaptation to environments and relationships that, in conditions of risk for the emergence of developmental psychopathology, motivates patterns of emotional responding that serve immediate coping often at the cost of long-term maladaptation. Implications for emotions theory and the study of developmental psychopathology are also considered.