Externalizing trajectories predict elevated inflammation among adolescents exposed to early institutional rearing: A randomized clinical trial

Foster Care Leads to Lower Irritability Among Adolescents with a History of Early Psychosocial Deprivation

Irritability reflects a propensity for frustration and anger, and is a transdiagnostic symptom of both externalizing and internalizing psychopathology. While early adverse experiences are associated with higher levels of irritability, experiences of early psychosocial deprivation and whether family-based placements can mitigate the impact on subsequent irritability, remain underexplored. The current study examined irritability in 107 16-year-olds with a history of institutional care from a randomized controlled trial of foster care as an alternative to institutional care and 49 community comparison children. At age 16 years, irritability was assessed using parent- and self-report forms of the Affective Reactivity Index. Compared to community adolescents, those with a history of institutional care exhibited significantly elevated irritability levels. Among those who experienced institutional care, those randomized to foster care had lower levels of irritability compared to participants randomized to the care-as-usual group, and this effect persists after controlling for baseline negative emotionality. These findings suggest a causal link between high-quality foster care and lower irritability following psychosocial deprivation. Additionally, longer duration in institutional care and non-family placement at age 16 years were associated with higher levels of irritability, highlighting the role of caregiving in explaining variation in irritability in adolescence. Policies that support long-term, high-quality family placements for children without regular caregivers should be prioritized.

Non-invasive diagnosis and monitoring tool of children’s mental health: A point-of-care immunosensor for IL-6 quantification in saliva samples

Mental disorders are commonly featured as chronic conditions with often onset during childhood. In this context, inflammation has been associated with a higher risk of developing physical and mental health problems. Interleukin (IL)-6 is a key mediator of inflammatory responses and plays a pivotal role in immune and nervous system interaction. High levels of IL-6 during childhood are associated with mental problems, indicating that the IL-6 molecular pathway may represent a new target for monitoring and treating these conditions. Here, we report the detection of IL-6 in saliva samples from children (N = 118, mean age 4.4 years old) with behavioral problems using an immunosensor based on electrochemical impedance spectroscopy. This work demonstrates that the proposed immunosensor requires smaller sample volumes and is significantly faster and more sensitive than conventional ELISA while maintaining comparable levels of specificity and reproducibility. The point-of care immunosensor for detection of IL-6 in saliva samples presented herewith is, therefore, an attractive solution to the clinical practice as a rapid non-invasive, high-sensitive monitoring tool of mental health problems, especially in vulnerable patient populations such as children.

Infant inflammation predicts childhood emotional and behavioral problems and partially mediates socioeconomic disadvantage

BACKGROUND

Emotional and behavioral problems (EBP) are common in children. Environmental factors like socioeconomic disadvantage influence EBP pathogenesis and can trigger inflammation. However, the link between early inflammation-EBP in children is unclear. We investigated the associations between i) infant inflammatory biomarkers and subsequent EBP and ii) early life environmental factors and EBP and assessed whether infant inflammation mediated these associations.

METHODS

Inflammatory biomarkers glycoprotein acetyls (GlycA) and high-sensitivity C-reactive protein (hsCRP) were quantified at birth and 12 months in a population-derived birth cohort, the Barwon Infant Study. Early life factors including demographic, prenatal, and perinatal factors were collected from antenatal to the two-year period. Internalizing and externalizing problems at age two were measured by the Child Behavior Checklist. Prospective associations were examined by multivariable regression analyses adjusted for potential confounders. Indirect effects of early life factors on EBP through inflammation were identified using mediation analyses.

RESULTS

Elevated GlycA levels at birth (GlycAbirth) were associated with greater internalizing problems at age two (β = 1.32 per SD increase in GlycA; P = 0.001). Inflammation at birth had a stronger magnitude of effect with later EBP than at 12 months. GlycAbirth partially mediated the associations between lower household income (6%), multiparity (12%) and greater number of older siblings (13%) and EBP. Patterns were less evident for hsCRP or externalizing problems.

CONCLUSIONS

GlycAbirth was positively associated with EBP at age two and partially mediated the association between several indicators of socioeconomic disadvantage and EBP. Prenatal and perinatal inflammation may be relevant to early neurodevelopment and emotional health.

Increased incidence of childhood mental disorders following exposure to early life infection

Early life exposure to infectious diseases confers risk for adult psychiatric disorders but relatively few human population studies have examined associations with childhood mental disorder. Here we examined the effects of exposure to maternal infection during pregnancy, and child infectious diseases in early childhood (birth to age 4 years), in relation to first mental disorder diagnosis (age 5-13 years). The study sample comprised 71,841 children represented in a population cohort of children in New South Wales, Australia, followed from birth to early adolescence via linkage of administrative registers. Childhood exposure to infectious disease was determined during the prenatal period (i.e., maternal infection during gestation), and in early childhood (between birth and age 4 years) using the NSW Ministry of Health Admitted Patients data collection. Days to first diagnosis with a mental disorder was determined from recorded diagnoses between age 5-13 years in the NSW Ministry of Health's Admitted Patients, Emergency Department and Mental Health Ambulatory data collections. While crude hazard ratios for both prenatal infection and childhood infection exposures indicated significantly earlier diagnosis with mental disorders associated with both of these risk factors, only childhood infection exposure was associated with higher adjusted hazard ratios (aHR) for any diagnoses (aHR = 1.21, 95% CI = 1.11-1.32), externalising disorders (aHR = 1.45, 95% CI 1.18-1.79) and developmental disorders (aHR = 1.82, 95% CI 1.49-2.22) when the effects of maternal and early childhood (age < 5 years) mental disorders were taken into account. Exposure to infectious diseases during early childhood, but not prenatal infection exposure, appears to be associated with earlier diagnosis of mental disorders in childhood.

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.

The prospective association between stressful life events and inflammation among adolescents with a history of early institutional rearing

Early adversity has been shown to sensitize individuals to the effects of later stress and enhance risk of psychopathology. Using a longitudinal randomized trial of foster care as an alternative to institutional care, we extend the stress sensitization hypothesis to examine whether early institutional rearing sensitizes individuals to stressful events in adolescence engendering chronic low-grade inflammation. At baseline, institutionalized children in Romania (ages 6-31 months) were randomly assigned to foster care or to remain in usual care within institutions. A group of never-institutionalized children was recruited as an in-country comparison sample. At ages 12 and 16, participants reported stressful events. At age 16, Interleukin-6 (IL-6) and C-reactive protein (CRP) were derived from blood spots. Among children assigned to care as usual, more stressful events at age 12, but not age 16, were associated with higher IL-6. In the same group, stressful events at age 16 were associated with higher CRP, though these effects attenuated after adjusting for covariates. These associations were not observed in the foster care or never-institutionalized groups. The findings suggest that heightened inflammation following stress exposure is one pathway through which early neglect could compromise physical health. In contrast, early family care might buffer against these risks.

Trajectories of internalising and externalising symptoms and inflammation in the general child population

BACKGROUND

Elevations in inflammatory marker levels have been shown to precede internalising and externalising problems in the general child population. One study has found the reverse, that elevations in inflammatory marker levels in childhood follow internalising and externalising problems. However, the authors did not explore the role of the course of these problems in childhood or adjust for a number of potential confounders including psychosocial stressors and prenatal and perinatal exposures.

AIMS

To investigate the association in childhood between the growth of internalising and externalising symptoms and levels of inflammatory markers, while accounting for potential confounders.

METHODS

Using data from the Avon Longitudinal Study of Parents and Children, we tested the association between the trajectories of internalising (emotional and social) and externalising (hyperactivity and conduct) problems, at ages 4, 6, 8 and 9 years, and levels of C-reactive protein (CRP) and interleukin 6 (IL-6) at age 9 years. We analysed data (n = 4525) using latent growth curve modelling and linear regression.

RESULTS

Children who had increasing levels of internalising symptoms over childhood were more likely to have higher levels of CRP and IL-6 at 9 years of age, even after adjustment for confounders. A one-unit increase in the rate of annual change of internalising symptoms was related to an increase of 12% and 8% in the level of CRP and IL-6, respectively. However, there was no evidence for an association between externalising symptoms and either inflammatory marker.

CONCLUSIONS

This study is the first step towards identifying a robust pathway, via increases in emotional and social difficulties, to elevated inflammation in healthy children. This association, if causal, suggests that effective interventions for children experiencing chronic emotional and social difficulties could also have physical health benefits.

The psychobiological consequences of child separation at the border: lessons from research on attachment and emotion regulation

In the spring of 2018, the Attorney General of the United States issued a memorandum declaring a "zero tolerance policy" under which all adults entering the United States illegally would be criminally prosecuted, and, if traveling with minor children, forcibly separated from their children. Although the government was ordered to reunite the children with their parents it is still unclear how many children have been or remain separated. Given the high risk of permanent harm to a vulnerable population, and the fact that this risk may continue into the near future, we present a review of what nearly eight decades of scholarly research has taught us about the damaging impact of deprivation and separation from parents. The article briefly reviews the origins of attachment theory as well as empirical studies that examine the psychobiological impact on children who experienced parental deprivation or separation. The paper concludes with recommendations, for future research.