The lifetime experience of traumatic events is associated with hair cortisol concentrations in community-based children

The relationship between hair cortisol concentration and autism diagnosis

BACKGROUND

Autistic children are prone to experience heightened levels of distress and physiological reactivity to a range of sensory, social, and emotional stimuli. In line with this, multiple studies have demonstrated that autistic children have higher acute cortisol stress responses to adverse or threatening stimuli and altered cortisol awakening responses. However, few studies have examined whether this sensitivity may relate to heightened levels of chronic stress and persistently elevated hypothalamic-pituitary-adrenal (HPA) axis activity. The measurement of cortisol accumulation in hair is considered a non-invasive biomarker of chronic stress and has been associated with several childhood diseases. Here, we investigated whether hair cortisol concentration in a large sample of autistic children differed from non-autistic children, and after accounting for a range of child, parental and family-level characteristics.

METHODS

Hair cortisol concentration was measured in 307 autistic children and 282 non-autistic controls aged between 2 and 17 years recruited from four Australian states who participated in providing hair samples and demographic data to the Australian Autism Biobank. Independent samples t-test or one-way analysis of variance (ANOVA) were conducted to determine significant differences in the mean hair cortisol concentration (pg/mg) between potential covariates. Primary analysis included multivariable regression modelling of the collapsed sample to identify variables that were significantly associated with hair cortisol concentration after controlling for covariates. We also accounted for the potential interaction of multiple biological (e.g., age, sex, BMI) and psychosocial characteristics at the level of the child, the mother and the father, and the family unit.

RESULTS

Our findings suggest that the diagnosis of autism was not a significant predictor of chronic stress, as measured by hair cortisol concentration. However, findings of the multivariable regression analysis showed that key factors such as area of residence (Queensland vs Victorian state of residence) and decrease in child's age were significantly associated with higher hair cortisol concentration whereas lower family income was significantly associated with higher hair cortisol concentration.

CONCLUSION

To our knowledge, this is the first study to show that socioeconomic factors such as family annual income affect hair cortisol status in autistic children, indicating that the psychosocial environment may be a potential mediator for chronic stress in autistic children just as it has been demonstrated in non-autistic children.

Association between maltreatment, hair cortisol concentration, positive parent-child interaction, and psychosocial outcomes in Chinese preschool children

Children now are facing an increasing risk of early life stress (ELS), which leads to detrimental psychosocial outcomes. Behavior studies suggested that positive parental interactions might moderate the negative impact of ELS, but the related biological alteration remains unclear. This study aims to investigate whether positive parent-child interactions moderate the association between maltreatment (as a severe form of ELS) and hair cortisol concentration (HCC), as well as between HCC and psychosocial outcomes in young children. Participants were 6-year-old Chinese children (N = 257, Mage = 6.2, 121 were male) selected by stratified cluster random sampling from a Shanghai population representative cohort. Proximal 3 cm hair strands were analyzed using liquid chromatography coupled with tandem mass spectrometry for HCC. Children's psychosocial outcome was evaluated using the parental report Strengths and Difficulties Questionnaire (SDQ). Parents also reported the frequency of positive parent-child interactions using the Chinese Parent-Child Interaction Scale (CPCIS) as well as the history of maltreatment. Multi-level logistic regression models adjusting for individual, kindergarten, and district confounders were used to evaluate the associations between maltreatment, HCC, and psychosocial outcomes. Interactions terms tested whether more frequent positive parent-child interactions moderates the association between maltreatment and HCC, as well as between HCC and psychosocial outcomes. Maltreated children exhibited higher levels of HCC (B = 1.20, 95% CI: 0.38,2.02; p = 0.004), and children with higher HCC exhibited poorer psychosocial outcomes (B = 0.34, 95% CI: 0.18,0.51; p < 0.001). Positive parent-child interactions did not have a moderating effect on the association between maltreatment and HCC, but they demonstrated a moderating effect on the association between increased HCC and psychosocial outcomes (interaction term: B = -0.42, 95% CI: -0.75,-0.10; p = 0.01). These findings provide evidence that positive parental interaction may serve as a moderator between chronic cortisol exposure and psychosocial problems. It highlights the importance of frequent parent-child interactions, especially among children under a high risk of ELS.

Hair cortisol determinants in 11-year-old children: Environmental, social and individual factors

INTRODUCTION

Children's exposure to chronic stress is associated with several health problems. Measuring hair cortisol concentration is particularly useful for studying chronic stress but much is unknown about hair cortisol determinants in children and adolescents, and previous research has often not considered the simultaneous exposure of multiple variables. This research is focused on investigating the relationship between environmental, social and individual factors with hair cortisol concentration in children.

METHODS

The data used in this study are from the INMA prospective epidemiological cohort study. The assessment of chronic stress was made on the basis of hair samples taken at the age of 11 years in the INMA-Gipuzkoa cohort (n = 346). A metamodel summarizing the hypothesized relationships among environmental, social and individual factors and hair cortisol concentration was constructed based on previous literature. Structural Equation Modelling was performed to examine the relationships among the variables.

RESULTS

In the general model higher behavioural problems were associated with higher cortisol levels and an inverse relationship between environmental noise and cortisol levels was observed, explaining 5 % of the variance in HCC. Once stratified by sex these associations were only hold in boys, while no significant effect of any of the study variables was related with cortisol levels in girls. Importantly, maternal stress was positively related to behavioural difficulties in children. Finally, higher traffic-related air pollution and lower exposure to neighborhood greenness were related to higher environmental noise.

DISCUSSION

This study highlights that simultaneous exposure to different environmental, social and individual characteristics may determine the concentration of hair cortisol. More research is needed and future studies should include this complex view to better understanding of hair cortisol determinants in children.

Continuity of psychopathology v. resilience across the transition to adolescence: role of hair cortisol and sensitive caregiving

BACKGROUND

The transition to adolescence implicates heightened vulnerability alongside increased opportunities for resilience. Contexts of early life stress (ELS) exacerbate risk; still, little research addressed biobehavioral mediators of risk and resilience across the adolescent transition following ELS. Utilizing a unique cohort, we tested biosocial moderators of chronicity in adolescents' internalizing disorders v. resilience.

METHOD

Families exposed to chronic war-related trauma, v. controls, were followed. We utilized data from three time-points framing the adolescent transition: late childhood (N = 177, Mage = 9.3 years ± 1.41), early adolescence (N = 111, Mage = 11 0.66 years ± 1.23), and late adolescence (N = 138, Mage = 15.65 years ± 1.31). In late childhood and late adolescence children's internalizing disorders were diagnosed. At early adolescence maternal and child's hair cortisol concentrations (HCC), maternal sensitivity, and mothers' post-traumatic symptoms evaluated.

RESULTS

War-exposed children exhibited more internalizing disorders of chronic trajectory and mothers were less sensitive and more symptomatic. Three pathways elucidated the continuity of psychopathology: (a) maternal sensitivity moderated the risk of chronic psychopathology, (b) maternal post-traumatic symptoms mediated continuity of risk, (c) trauma exposure moderated the association between child internalizing disorders at late childhood and maternal HCC, which linked with child HCC. Child HCC linked with maternal post-traumatic symptoms, which were associated with child disorders in late adolescence.

CONCLUSION

Results demonstrate the complex interplay of maternal and child's biosocial factors as mediators and moderators of risk chronicity across the adolescent transition following trauma. Findings are first to utilize maternal and child's HCC as biomarkers of chronic stress v. resilience during adolescence, a period of neural reorganization and personal growth that shapes the individual's lifetime adaptation.

Hair cortisol concentrations and perceived stress in 7-year-old children at familial high-risk of schizophrenia or bipolar disorder

BACKGROUND

Dysregulation of the HPA-axis, perceived stress and interpersonal trauma are associated with an elevated risk for schizophrenia and bipolar disorder. Being at familial high-risk of these two mental disorders also constitutes an increased risk. In this study, we aimed to investigate hair cortisol concentrations and perceived stress among 7-year-old children at familial high-risk of schizophrenia (FHR-SZ), bipolar disorder (FHR-BP), and population-based controls (controls).

METHODS

A total of 515 children (mean age 7.8, SD 0.2) from baseline assessment of the Danish High Risk and Resilience Study - VIA 7 participated in this study. Hair cortisol concentrations were analyzed among 322 children (FHR-SZ; N = 111, FHR-BP; N = 82, controls; N = 129). Perceived stress was assessed with the Daily Life Stressor Scale including 512 children (FHR-SZ; N = 195, FHR-BP; N = 118, controls; N = 199). Interpersonal trauma was measured with face-to-face interviews.

RESULTS

Seven-year-old children at FHR-SZ or FHR-BP did not have a higher level of hair cortisol concentrations compared with controls (FHR-SZ: mean: 5.10, 95%CI 3.69-6.52; FHR-BP: mean: 5.01, 95%CI 3.27-6.72; controls: mean: 4.51, 95%CI 3.61-5.40; p = 0.77). Self-reported perceived stress was higher among children at FHR-SZ and FHR-BP compared with controls (FHR-SZ: mean: 12.09, 95%CI 10.99-13.19; FHR-BP: mean: 10.69, 95%CI 9.38-11.99; controls: mean: 8.90, 95%CI 8.13-9.68; p < 0.001). There was no significant association between hair cortisol concentrations and perceived stress (p = 0.84). Exploratory analyses revealed that interpersonal trauma exposure was neither associated with elevated hair cortisol nor perceived stress.

CONCLUSIONS

Children at FHR-SZ and FHR-BP did not exhibit higher levels of hair cortisol concentrations at age 7, while both FHR-groups had higher level of self-reported perceived stress compared with controls. Early attention to stress in children at FHR is crucial and these vulnerabilities should be targeted in future interventions studies.

Hair Cortisol Concentration as a Biomarker of Symptoms of Depression in the Perinatal Period

Pregnancy is a sensitive period when women experience major hormonal and psychological changes. A high prevalence of the symptoms of depression and manifested major depression rates have been reported during this period, leading to negative outcomes both for mothers and the offspring. Despite its prevalence, the aetiology of depression is not yet fully understood. Nonetheless, alterations in cortisol levels have been proposed as a reliable biomarker to identify pregnant women at risk of perinatal depression. Hair cortisol has recently been extensively used in bio-psychological studies as a suitable non-invasive biomarker for several neuropsychiatric disorders. Various studies have published evidence regarding the relationship between cortisol fluctuations during the perinatal period, measured both in hair and in other substrates, and the onset of perinatal symptoms of depression. This current review provides an overview of cortisol level changes measured in women's hair during pregnancy or the postpartum period and its association with perinatal symptoms of depression. Further studies, including repetitive measurement of both hair cortisol and depression throughout the prenatal period, must be performed to clarify the relationship between cortisol levels and perinatal symptoms of depression.

Potential peripheral biomarkers associated with the emergence and presence of posttraumatic stress disorder symptomatology: A systematic review

BACKGROUND

Evidence suggests posttraumatic stress disorder (PTSD) involves an interplay between psychological manifestations and biological systems. Biological markers of PTSD could assist in identifying individuals with underlying dysregulation and increased risk; however, accurate and reliable biomarkers are yet to be identified.

METHODS

A systematic review following the PRISMA guidelines was conducted. Databases included EMBASE, MEDLINE, and Cochrane Central. Studies from a comprehensive 2015 review (Schmidt et al., 2015) and English language papers published subsequently (between 2014 and May 2022) were included. Forty-eight studies were eligible.

RESULTS

Alterations in neuroendocrine and immune markers were most commonly associated with PTSD symptoms. Evidence indicates PTSD symptoms are associated with hypothalamic-pituitary-adrenal axis dysfunction as represented by low basal cortisol, a dysregulated immune system, characterized by an elevated pro-inflammatory state, and metabolic dysfunction. However, a considerable number of studies neglected to measure sex or prior trauma, which have the potential to affect the biological outcomes of posttraumatic stress symptoms. Mixed findings are indicative of the complexity and heterogeneity of PTSD and suggest the relationship between allostatic load, biological markers, and PTSD remain largely undefined.

CONCLUSIONS

In addition to prospective research design and long-term follow up, it is imperative future research includes covariates sex, prior trauma, and adverse childhood experiences. Future research should include exploration of biological correlates specific to PTSD symptom domains to determine whether underlying processes differ with symptom expression, in addition to subclinical presentation of posttraumatic stress symptoms, which would allow for greater understanding of biomarkers associated with disorder risk and assist in untangling directionality.

Examining the relationships between adverse childhood experiences (ACEs), cortisol, and inflammation among young adults

Adverse childhood experiences (ACEs) are associated with dysregulation of inflammation and cortisol. The objectives of this study were to use principal component analysis to explore the inflammatory biomarker data to create inflammation composite variables; to examine the relationship between these composite measures of inflammation with ACEs and cortisol; and to assess whether these relationships were moderated by sex. The analysis included 232 young adults from the Niagara Longitudinal Heart Study (NLHS). After adjusting for covariates, higher exposure to ACEs significantly predicted higher low-grade inflammation. These results further support the use of multiple biomarkers to understand the complex relationships among ACEs, cortisol, and inflammation, which should be further examined in longitudinal studies to study biomarker trajectories.

Hair cortisol as a biomarker of chronic stress in preadolescents: influence of school context and bullying

Bullying has been identified as the most common form of aggression and a major source of stress among children and adolescents. The main objective of this study was to analyze the association that school context in general and bullying in particular might have with hair cortisol concentration (HCC), examining the effect of executive function and sex on this association. The study included 659 11-year-old preadolescents from the cohorts of Gipuzkoa and Sabadell of the INMA (INfancia y Medio Ambiente-Children and Environment) project. We gathered information about school-related factors (bullying, school environment, problems with peers and academic performance) and executive function (risky decision-making). Hair samples were collected to measure cortisol concentrations and Structural Equation Modeling was used to examine associations between school-related factors, executive function and HCC. Results showed that being involved as a bully/victim was related to higher HCC and, higher HCC was associated with poorer executive function. This study may contribute to a better understanding of the consequences that chronic exposure to a stressful factors may have on preadolescents' health and developmental outcomes. Besides, our results are relevant for designing programs for prevention and intervention, which could modify individual physiological responses to stress and reduce the effects of stress on the health.

The effect of cumulative early life adversities, and their differential mediation through hair cortisol levels, on childhood growth and cognition: Three-year follow-up of a birth cohort in rural India

Background: Early adversities negatively impact children's growth and development, putatively mediated by chronic physiological stress resulting from these adverse experiences. We aimed to estimate the associations between prospectively measured cumulative early adversities with growth and cognition outcomes in rural Indian preschool children and to explore if hair cortisol concentration (HCC), a measure of chronic physiological stress, mediated the above association. Methods: Participants were recruited from the SPRING cRCT in rural Haryana, India. Adversities experienced through pregnancy and the first year of life were measured in 1304 children at 12-months. HCC was measured at 12-months in 845 of them. Outcome measures were height-for-age-z-score (HAZ), weight-for-age-z-score (WAZ) and cognition, measured in 1124 children followed up at 3-years. Cognition was measured using a validated tablet-based gamified tool named DEEP. Results: Cumulative adversities at 12-months were inversely associated with all outcomes measures at 3-years. Each unit increase in adversity score led to a decrease of 0·08 units [95% confidence interval (CI):-0·11,-0·06] in DEEP-z-score; 0·12 units [-0·14,-0·09] in HAZ and 0·11 units [-0·13,-0·09] in WAZ. 12-month HCC was inversely associated with DEEP-z-score (-0·09 [-0·16,-0·01]) and HAZ (-0·12 [-0·20,-0·04]), but the association with WAZ was not significant (p = 0·142). HCC marginally mediated the association between cumulative adversities and HAZ (proportion mediated = 0·06, p = 0·014). No evidence of mediation was found for the cognition outcome. Conclusions: Cumulative early adversities and HCC measured at 12-months have persistent negative effects on child growth and cognition at 3-years. The association between adversities and these two child outcomes were differentially mediated by HCC, with no evidence of mediation observed for the cognitive outcome. Future studies should focus on other stress biomarkers, and alternate pathways such as the immune, inflammation and cellular ageing pathways, to unpack key mechanisms underlying the established relationship between early adversities and poor child outcomes.

The effect of cumulative early life adversities, and their differential mediation through hair cortisol levels, on childhood growth and cognition: Three-year follow-up of a birth cohort in rural India

Background: Early adversities negatively impact children’s growth and development, putatively mediated by chronic physiological stress resulting from these adverse experiences. We aimed to estimate the associations between prospectively measured cumulative early adversities with growth and cognition outcomes in rural Indian preschool children and to explore if hair cortisol concentration (HCC), a measure of chronic physiological stress, mediated the above association. Methods: Participants were recruited from the SPRING cRCT in rural Haryana, India. Adversities experienced through pregnancy and the first year of life were measured in 1304 children at 12-months. HCC was measured at 12-months in 845 of them. Outcome measures were height-for-age-z-score (HAZ), weight-for-age-z-score (WAZ) and cognition, measured in 1124 children followed up at 3-years. Cognition was measured using a validated tablet-based gamified tool named DEEP. Results: Cumulative adversities at 12-months were inversely associated with all outcomes measures at 3-years. Each unit increase in adversity score led to a decrease of 0·08 units [95% confidence interval (CI):-0·11,-0·06] in DEEP-z-score; 0·12 units [-0·14,-0·09] in HAZ and 0·11 units [-0·13,-0·09] in WAZ. 12-month HCC was inversely associated with DEEP-z-score (-0·09 [-0·16,-0·01]) and HAZ (-0·12 [-0·20,-0·04]), but the association with WAZ was not significant (p = 0·142). HCC marginally mediated the association between cumulative adversities and HAZ (proportion mediated = 0·06, p = 0·014). No evidence of mediation was found for the cognition outcome. Conclusions: Cumulative early adversities and HCC measured at 12-months have persistent negative effects on child growth and cognition at 3-years. The association between adversities and these two child outcomes were differentially mediated by HCC, with no evidence of mediation observed for the cognitive outcome. Future studies should focus on other stress biomarkers, and alternate pathways such as the immune, inflammation and cellular ageing pathways, to unpack key mechanisms underlying the established relationship between early adversities and poor child outcomes.

A randomized controlled trial of an emotion socialization parenting program and its impact on parenting, children's behavior and parent and child stress cortisol: Tuning in to Toddlers

This paper examines the efficacy of a universally-offered parenting program, Tuning in to Toddlers (TOTS), that aims to improve parent emotion socialization, reduce parent and toddler stress and improve social, emotional, and behavioral functioning in toddlers. Three hundred parents of an 18-36 month old toddler were cluster randomized into intervention or control. Parents in the intervention participated in 6 × 2 h group sessions of TOTS. Baseline and 12-months post-intervention measures were collected using parent-report questionnaires and hair samples from parents and toddlers of systemic cortisol stress. Compared to controls, intervention parents reported significantly greater reductions in difficulties in emotion regulation (difficulty remaining goal directed: 95% CI.10, 1.71, p = .028; lack of access to strategies: 95% CI 0.62, 2.42, p = .001), emotion dismissing (beliefs: 95% CI 2.33,4.82, p < .001; behaviors: 95% CI 0.32, 0.65, p = <.001), greater increase in empathy (95% CI -2.83, -1.50, p < .001), emotion coaching (beliefs: 95% CI -2.56, -0.27, p = .016; behaviors: 95% CI -0.58, -0.24, p = <.001), children's behavior (95% CI 0.19, 2.43, p = .022) and competence (95% CI -1.46, -0.22, p = .008). Significant greater reductions in systemic cortisol were found for intervention but not control children (95% CI 0.01, 0.35, p = .041). Findings provide preliminary support for the use of TOTS as a universal prevention program to improve parent emotion socialization and children's functioning. Trial Registration: Australian and New Zealand Clinical Trials Registry: ACTRN12615000962538.

Developmental Consequences of Early Life Stress on Risk for Psychopathology: Longitudinal Associations with Children's Multisystem Physiological Regulation and Executive Functioning

The etiology of psychopathology is multifaceted and warrants consideration of factors at multiple levels and across developmental time. Although experiences of adversity in early life have been associated with increased risk of developing psychopathology, pathways toward maladaptation or resilience are complex and depend upon a variety of factors, including individuals' physiological regulation and cognitive functioning. Therefore, in a longitudinal cohort of 113 mother-child dyads, we explored associations from early adverse experiences to physiological co-regulation across multiple systems and subsequent variations in executive functioning. Latent profile analysis derived multisystem profiles based on children's heart rate, respiratory sinus arrhythmia, pre-ejection period, and cortisol measured during periods of rest and reactivity throughout a developmentally challenging protocol. Three distinct profiles of multisystem regulation emerged: heightened multisystem baseline activity (Anticipatory Arousal/ANS Responder), typically adaptive patterns across all systems (Active Copers/Mobilizers) and heightened HPA axis activity (HPA Axis Responders). Path models revealed that children exposed to adversity before 18-months were more likely to evidence an Anticipatory Arousal/ANS Responders response at 36-months, and children in this profile had lower executive functioning scores than the Active Copers/Mobilizers. In sum, these findings provide important information about potential physiological associations linking early adversity to variations in children's task-based executive functioning.

Children's hair cortisol and hair testosterone concentrations in response to environmental changes: from summer holidays to school

Elevated hair cortisol concentrations in children have been linked to several stress-related conditions, including school-related demands. However, little is known about changes in hair testosterone in children. The present study investigated changes in hair cortisol and hair testosterone concentrations in the time course of four months - from summer holidays until mid of autumn of the following school year - in 60, 10-12-year-old (11.31 ± 0.63) school children (29 girls). Children's mental health was assessed by the strengths and difficulties questionnaire (SDQ) and related to hair cortisol and hair testosterone levels. Body mass index, waist-to-height ratio, and parental education were evaluated as potential confounders. In girls, the expected increase of hair cortisol concentrations was observed during school as compared to summer holidays, partly accounted for by peer- and emotional problems and the increase of HTC. In boys, hair cortisol and testosterone concentrations were significantly higher. Hair cortisol increased only slightly, while hair testosterone decreased significantly during school. The findings suggest a reciprocal influence of the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axis, differentially affecting girls' and boys' hormone production in response to environmental changes.

Alterations of autonomic nervous system and HPA axis basal activity and reactivity to acute stress: a comparison of traumatized adolescents and healthy controls

Alterations in neurobiological stress systems such as the autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis contribute to the development and maintenance of psychological and behavioral problems after traumatic experiences. Investigating neurobiological parameters and how these relate to each other may provide insight into the complex mechanisms at play. Whereas the preponderance of studies focuses on either the ANS or the HPA axis separately, the current study is the first to evaluate relations between posttraumatic stress and both basal activity during rest and stress reactivity of the ANS as well as the HPA axis in a sample of traumatized adolescents and healthy controls. The traumatized sample (n = 77), based on clinical levels of posttraumatic stress, was a convenience sample that was recruited within residential institutions, was compared to a healthy control sample (n = 48) recruited within the general community. For the ANS, we expected increased SNS and decreased PNS activity during rest and increased SNS and decreased PNS reactivity to social stress among traumatized adolescents compared to healthy controls. Regarding the HPA axis, we expected increased basal cortisol levels and decreased cortisol reactivity to stress in the traumatized sample. Compared to healthy controls, traumatized adolescents exhibited significantly higher sympathetic and lower parasympathetic activation during rest and increased sympathetic reactivity to acute stress (ANS parameters). Outcomes on the HPA axis (i.e. cortisol) indicated that traumatized adolescents showed increased cortisol levels during rest and blunted cortisol reactivity to acute stress. Implications for clinical relevance and trauma-focused treatment purposes are discussed.

Racial and Economic Adversity Differences in Stress Markers and Immune Function Among Urban Adolescents

BACKGROUND

Exposure to racism and associated adversities, such as poverty, is hypothesized to contribute to racial inequities in health via stress and immune pathways. Furthermore, the effects of adversity may be more salient during sensitive developmental periods. Our study examined racial differences in stress and immune biomarkers during adolescence and the effects of exposure to economic adversity at distinct developmental time periods and cumulatively in accounting for potential racial differences.

METHODS

Secondary analysis of the Adolescent Health and Development in Context study was conducted. Data were derived from self-administered surveys; interviews; smartphone-based, geographic-explicit ecological momentary assessment; stress biomarkers (evening salivary cortisol over six nights and hair cortisol); and immune biomarkers (salivary shedding of Epstein-Barr virus [EBV] DNA among EBV-positive adolescents). Current socioeconomic status measures included annual household income and caregiver education. Caregivers also reported experiences of bankruptcy, difficulty paying bills, receipt of food stamps/Supplemental Nutrition Assistance Program/electronic benefit transfer, and job loss when the child was of ages birth-5 years, 6-10 years, and 11 years or older. An affirmative response to any item was defined as exposure to economic adversity for that developmental time period (yes/no). A cumulative economic adversity measure was calculated as the sum of exposures across developmental periods (0 = never exposed to 3 = exposed across all time periods). Descriptive and multivariable regression analyses were conducted, accounting for covariates.

RESULTS

Black/African American adolescents had higher salivary cortisol concentration, higher hair cortisol concentration, and an increased odd of salivary shedding of EBV DNA compared to White adolescents. Racial differences were not attenuated by the current socioeconomic status or economic adversity (developmental period or cumulatively).

DISCUSSION

Our study provides evidence that stress and immune biomarkers differ by race as early as adolescence and may be one pathway through which racism and associated adversities contribute to racial health inequities. Further research on the contribution of multiple adversities beyond poverty to racial inequities in physiological stress and health is critical for informing effective prevention and intervention efforts.

Stress in the onset and aggravation of learning disabilities

Despite substantial grounds for such research, the role of chronic exposure to stressors in the onset and aggravation of learning disabilities (LDs) is largely unexplored. In this review, we first consider the hormonal, (epi)genetic, and neurobiological mechanisms that might underlie the impact of adverse childhood experiences, a form of chronic stressors, on the onset of LDs. We then found that stress factors combined with feelings of inferiority, low self-esteem, and peer victimization could potentially further aggravate academic failures in children with LDs. Since effective evidence-based interventions for reducing chronic stress in children with LDs could improve their academic performance, consideration of the role of exposure to stressors in children with LDs has both theoretical and practical importance, especially when delivered in combination with academic interventions.

Cumulative exposure to socioeconomic and psychosocial adversity and hair cortisol concentration: A longitudinal study from 5 months to 17 years of age

BACKGROUND

Exposure to early adversity has been associated with long-lasting risks for poor health and functioning. Prior research suggests that the hypothalamic-pituitary-adrenal (HPA) axis, and its main end-product glucocorticoid hormone cortisol, may be at play. This study tested whether an index of cumulative socioeconomic and psychosocial adversity assessed prospectively, from infancy to adolescence, was associated with hair cortisol concentration (HCC), and if this association differed by sex.

METHODS

The sample comprised 556 adolescents (42.0% males) who provided hair for cortisol measurement at 17 years of age. Adversity indicators (young and single motherhood, low socioeconomic status (SES), maternal alcohol use, hostile-reactive parenting, and depressive symptoms, as well as peer victimization and neighborhood dangerousness) were repeatedly reported by mothers or youths between the ages of 5 months and 15 years.

RESULTS

Chronic adversity was non-linearly associated with HCC; youth exposed to lower and higher levels of adversity had moderate-to-higher HCC compared to lower HCC noted in participants with moderate levels of adversity, for both males and females. None of the indicators taken separately, except the perception of neighborhood dangerousness, were significantly associated with HCC.

CONCLUSION

Our findings support the hypothesis that HPA axis activity varies according to cumulative adversity, albeit non-linearly, which may bear consequences for later health and functioning.

Validation of the Lifetime Incidence of Traumatic Events (LITE-S/P) Questionnaires in Children and Adolescents in Slovenia

Introduction: A traumatic event is an extremely threatening and frightening experience in an individual's life. Children who are exposed to traumatic events are twice as likely to develop a mental disorder. Screening can provide insight into the traumatic experience of children, identifying those eligible for further evaluation, and support. With this aim, we evaluated the psychometric properties of the Lifetime Incidence of Traumatic Events questionnaire (LITE) in Slovene by calculating retest reliabilty, construct validity (cross-informant agreement) and external validity, where we calculated the correlation of the number of differenet traumatic events with psychopathological symptoms. Methods: 280 child-parent pairs (children aged 11.3 ± 2.2 years) from various Slovenian primary schools participated in the study. They were divided into two groups: 180 healthy primary school students and 100 children with Type 1 Diabetes (our study was a part of a larger study The Influence of Psychobiological Adversity on Children and Adolescents with Type 1 Diabetes Study). Two versions of the LITE questionnaire were used. Children completed the child report (LITE-S) and parents the parent report (LITE-P) version. After 4 weeks, 117 children, and 114 parents filled out the LITEs again. External validity was assessed using the Youth Self Report and Child Behaviour Checklist syndrome-oriented scales. Results: Retest reliability for individual scales was r = 0.469-0.639 (ρ = 0.443-0.636; p < 0.001), but higher for individual items (κ = 0.263-0.821; p < 0.001). Correlations between reports from parents and children were r = 0.313-0.345 (ρ = 0.317-0.348; p < 0.001). The number of different events experienced by children correlated significantly with the measured depressive-anxiety, and posttraumatic stress disorder symptoms. Conclusions: Based on our results, the LITE-S and LITE-P "All events" scale have acceptable psychometric properties for use in research and in clinical practise screening. We recommend looking at single items, taking into consideration the responses from both the child and the parent for more precise information. To improve the precision of the psychodiagnostic capacity of the questionnaire, further research on various populations should be performed.

The social ecology of childhood and early life adversity

An increasing prevalence of early childhood adversity has reached epidemic proportions, creating a public health crisis. Rather than focusing only on adverse childhood experiences (ACEs) as the main lens for understanding early childhood experiences, detailed assessments of a child's social ecology are required to assess "early life adversity." These should also include the role of positive experiences, social relationships, and resilience-promoting factors. Comprehensive assessments of a child's physical and social ecology not only require parent/caregiver surveys and clinical observations, but also include measurements of the child's physiology using biomarkers. We identify cortisol as a stress biomarker and posit that hair cortisol concentrations represent a summative and chronological record of children's exposure to adverse experiences and other contextual stressors. Future research should use a social-ecological approach to investigate the robust interactions among adverse conditions, protective factors, genetic and epigenetic influences, environmental exposures, and social policy, within the context of a child's developmental stages. These contribute to their physical health, psychiatric conditions, cognitive/executive, social, and psychological functions, lifestyle choices, and socioeconomic outcomes. Such studies must inform preventive measures, therapeutic interventions, advocacy efforts, social policy changes, and public awareness campaigns to address early life adversities and their enduring effects on human potential. IMPACT: Current research does not support the practice of using ACEs as the main lens for understanding early childhood experiences. The social ecology of early childhood provides a contextual framework for evaluating the long-term health consequences of early life adversity. Comprehensive assessments reinforced with physiological measures and/or selected biomarkers, such as hair cortisol concentrations to assess early life stress, may provide critical insights into the relationships between early adversity, stress axis regulation, and subsequent health outcomes.

Lifetime stressors, hair cortisol, and executive function: Age-related associations in childhood

Extant research is mixed regarding the relations among lifetime exposure to stressors, adrenocortical activity, and executive function (EF), particularly in children. Aggregate measures of adrenocortical activity like hair cortisol concentration (HCC), timing of stress exposure, and age at assessment may clarify these associations. This cross-sectional study examined the association among parent-reported exposure to stressors, hair cortisol concentration (HCC), and children's EF via a tablet task in a community sample (n = 318, 52.5% female) of children across a wide age range (4-13 years, M = 9.4, SD = 2.3). Path analyses revealed that parent-reported child lifetime exposure to stressors, but not past-year stressful life events, negatively predicted HCC. There was also a marginally significant moderation by age such that HCC was associated negatively with EF for younger children (age < 9.7 years) but not older children. HCC did not significantly mediate the association between lifetime exposure to stressors and EF. Findings are consistent with the proposition that chronically high cortisol production has a neurotoxic effect on brain regions supporting EF. However, lifetime exposure to stressors predicted relatively lower cumulative cortisol production, consistent with a stress inoculation effect in this normative-risk sample.

Association of maternal depression and home adversities with infant hypothalamic-pituitary-adrenal (HPA) axis biomarkers in rural Pakistan

BACKGROUND

Each year, almost 35% of children are exposed to maternal depression and more grow up in persistent poverty, increasing the risk for stress-related disease and other socio-developmental deficits later in life. These impacts are likely related to chronic stress via the hypothalamic-pituitary-adrenal (HPA) axis. However, there is little evidence relating early windows of child HPA axis activity to multiple exposures.

METHODS

We investigated chronic measures of hair-derived HPA axis hormones (cortisol and dehydroepiandrosterone (DHEA)) in 104 one-year old infants from rural Pakistan and longitudinal measures of maternal depression, intimate partner violence (IPV), socio-economic status (SES), and the home environment.

RESULTS

Estimates from adjusted linear mixed effects models did not reveal consistent significant associations between infant cortisol and maternal depression or home adversities. By contrast, infants exposed to maternal depression during pregnancy had lower DHEA levels (ß= -0.18 95% confidence interval [CI]: -0.34, -0.02) as did those whose mothers experienced multiple types of IPV (ß=-4.14 95% CI: -7.42, -0.79) within one year postpartum. Higher SES had a significant positive association with infant DHEA levels (ß= 0.77 95% CI: 0.08, 1.47). Depression severity and chronicity at one year postpartum had near significant associations with infant DHEA. Measures of home environment had no observable impacts on infant HPA axis activity.

LIMITATIONS

Limitations include the modest sample size and aggregation of hair samples for analysis.

CONCLUSION

Results point to possible early HPA axis dysregulation driven by changes in DHEA activity, but not cortisol at one year of age. Findings contribute to growing research examining intergenerational transmissions of maternal depression, IPV, and household environment on infant stress-response systems.

The long-term association of adverse childhood experiences with C-reactive protein and hair cortisol: Cumulative risk versus dimensions of adversity

BACKGROUND

Exposure to adverse childhood experiences (ACEs) may lead to stress-induced upregulation of inflammatory and neuroendocrine processes. However, it remains unclear whether such effects persist into later life, and which dimensions of ACEs might have the strongest impact on these biological mechanisms. Therefore, this study investigated the effects of ACEs on C-reactive protein (CRP) and hair cortisol in a large sample of older adults, distinguishing between cumulative exposure and dimensions of ACEs.

METHODS

We utilised data from the English Longitudinal Study of Ageing. ACEs were assessed through retrospective reports at wave 3(2006/07). CRP (N = 4198) was measured at waves 4(2008/09) and 6(2012/13), and hair cortisol (N = 3357) at wave 6. The effects of ACEs cumulative exposure were examined using linear and ordinal logistic regression analysis. ACEs dimensions (i.e. threat, household dysfunction, low parental bonding, and loss of an attachment figure) were identified using explorative and confirmatory factor analysis with cross-validation. All analyses were adjusted for relevant confounders.

RESULTS

Participants with three or more ACEs had higher CRP levels at wave 4 and an elevated risk of high CRP concentrations across waves 4 and 6 compared with those who did not experience any ACEs. The four ACEs dimensions were all positively associated with both CRP outcomes and had similar effect sizes. In contrast, neither the cumulative score nor the dimensions of ACEs were significantly related to hair cortisol. However, there was a positive, yet small, interaction effect between ACEs and age on hair cortisol.

CONCLUSION

Older adults who retrospectively reported three or more ACEs had chronically elevated CRP levels and exhibited a slightly steeper increase in hair cortisol with age. Different dimensions of ACEs had similar associations with the biomarkers.

Sex-specific associations between person and environment-related childhood adverse events and levels of cortisol and DHEA in adolescence

BACKGROUND

Person and environment-related childhood adverse events have been demonstrated to increase the risk of impaired mental health in later life differently for boys and girls. Altered hypothalamic pituitary adrenal (HPA)-axis functioning has been suggested as a key mechanism underlying this association. Cortisol and dehydroepiandrosterone (DHEA) are both output hormones of the HPA-axis. DHEA may have a protective function against long-term exposure to increased levels of cortisol, but has been little investigated in relation to childhood adversity.

OBJECTIVE

We aimed to test the associations between person-, and environment-related childhood adversity and levels of cortisol, DHEA and cortisol/DHEA ratio in adolescent boys and girls.

METHODS

A total of 215 Dutch adolescents participated in the study and filled out the 27-item Adverse Life Events Questionnaire for the assessment of childhood adversity, which was split up in separate scores for person-related and environment-related events. Cortisol and DHEA concentrations and cortisol/DHEA ratio were determined in proximal 3 cm long hair segments. Additionally, saliva samples were collected immediately and 30 minutes after waking up, at noon and at 8 pm. Multiple linear regression analyses were used to test associations between childhood adversity and cortisol and DHEA concentrations, for boys and girls separately, with age, BMI and pubertal development as covariates.

RESULTS

Data were available for 74 boys and 116 girls with a mean age of 15.7 years (SD = 2.0). Higher levels of person-related childhood adversity were associated with higher hair DHEA levels in girls and with higher hair cortisol levels in boys. A trend towards a significant association was observed between higher levels of environment-related childhood adversity and higher DHEA levels in boys. Neither person- nor environment related childhood adversity was associated with cortisol/DHEA ratio. A trend was observed for environment-related childhood adversity and lower daily cortisol output in boys.

CONCLUSION

We found differential associations between childhood adversity and cortisol and DHEA levels in girls and boys, for respectively person-related and environment-related childhood adversity. Our findings suggest that different types of childhood adversity are not only linked to levels of cortisol, but also to DHEA concentrations, in a sex-specific manner, with possible future implications for mental health.

The Moderating Role of Emotion Regulation in the Association Between Stressors With Psychological and Biological Measures in Adolescence

OBJECTIVE

This study explored the role of emotion regulation (ER) as a moderator in the stressor-adjustment outcome relationship while identifying the relevant stressors.

METHODS

In 214 adolescents (10-18 years; 51.4% boys), stressors (parent and peer relations, negative events), psychological outcomes (adolescent perceived stress, psychopathology symptoms, negative affect), and biological measures related to the stress response (hair cortisol [HC], heart rate variability [HRV]) as well as ER strategies-maladaptive (MalER), adaptive (AdER), and their ratio (Mal/AdER)-were measured and analyzed via linear regression, adjusted for age, sex, and socioeconomic status.

RESULTS

Parental rejection and bullying were the stressors with the strongest association with psychological outcomes (β range = |0.217-0.352|, p < .05). In addition, parental rejection was associated with HC (β = 0.242, p = .035), whereas none of the stressors were associated with HRV. MalER was linked to all, and AdER to most psychological outcomes (β range = |0.21-0.49|, p < .05). MalER, but not AdER, was associated with HC (β = 0.25, p = .009), whereas none of the ER strategy types were associated with HRV. Moreover, several associations between stressors and psychological outcomes were moderated by MalER and Mal/AdER, whereas AdER's role as a moderator was not confirmed.

CONCLUSIONS

The study confirmed that adolescents' stressors are associated with both psychological and physiological outcomes and moderated by MalER or Mal/AdER. The lack of moderation by AdER directs toward the maladaptive shift theory. Investigations through a longitudinal, rather than a cross-sectional design, could further elucidate the current observations. Moreover, training in how to use ER effectively has a potential of increasing adolescents' stress resilience.

Hair Cortisol Concentration in Healthy Children and Adolescents Is Related to Puberty, Age, Gender, and Body Mass Index

INTRODUCTION

Hair cortisol concentrations (HCC) have been found to be related to various common childhood diseases, like otitis media, conjunctivitis, respiratory viral infections, and asthma. However, the confounding effects of age, gender, body mass index (BMI), pubertal stage (Tanner stages), socioeconomic status (SES) as well as of some hair maintenance procedures on HCC are still not well examined.

METHODS

A population-based cohort of 434 children aged between 5 and 18 years was examined for HCC between January 2012 and February 2015 in the context of the Leipzig Research Centre for Civilization Diseases (LIFE) Child study. Thereby, anthropometric data, gender, BMI, SES and pubertal status were assessed. HCC was measured by liquid chromatography mass spectrometry.

RESULTS

In the total cohort, HCC levels ranged between 0.95 and 29.86 pg/mg. In prepuberty, boys showed significantly higher HCC than girls (6.54 vs. 3.73 pg/mg, p < 0.05). During puberty HCC values in both genders converged. Higher BMI was significantly associated with higher HCC in both genders. In girls, HCC did not differ depending on Tanner stages. In boys, HCC was significantly higher in Tanner stage 1 than in stages 2-5.

CONCLUSION

Measuring cortisol concentration in hair gives information about long-term release of cortisol. We have found that puberty, gender, and BMI had a profound effect on HCC. As a result, further research should take into account the potentially confounding role of puberty, gender and BMI and may use the results of our study as a reference at determining values of HCC in healthy children.

Hair cortisol concentration mediates the association between parent and child psychopathology

Parent and child mental health are strongly associated and this association may be transmitted via disruption to the hypothalamic-pituitary-adrenal axis in children. This study examined the potential mediating role of hair cortisol concentration (HCC) in the association between parent psychopathology and child mental disorder. Data come from 100 children diagnosed with a mental disorder [major depression (66 %), generalized anxiety (58 %), attention-deficit hyperactivity (33 %), oppositional defiant (35 %)] and their parents. Parent psychopathology was measured using the Center for Epidemiological Studies Depression Scale and State-Trait Anxiety Inventory. Child mental disorder was measured using the Mini International Neuropsychiatric Interview and hair samples were assayed using high-sensitivity ELISA for cortisol extraction. Sex-specific path models were specified to estimate mediating effects (αβ). Children were, on average, 14.4 (SD 2.3) years of age and 70 % were girls. Adjusting for child age, parent sex, and family income, HCC mediated the association between symptoms of parent psychopathology and major depression and attention-deficit hyperactivity in all children (αβ ranging -0.07 to 0.19; 38-46 % effect mediated). Mediating effects for generalized anxiety and opposition defiant were evident for boys only (αβ ranging -0.26 to 0.14; 31-38 % effect mediated). Evidence suggests HCC partially mediates the association between parent psychopathology and child mental disorder, and for generalized anxiety and oppositional defiant, this effect is specific to boys. Family inventions to reduce child stress may be effective in buffering the consequences of parent psychopathology. Further research that considers sex effects is needed to clarify how HCC conditions risk for mental disorder in children.

Using Hair Cortisol to Examine the Role of Stress in Children's Health Inequalities at 3 Years

OBJECTIVE

Children exposed to early adversity (eg, financial hardship, family violence, parent mental health difficulties) are at greater risk of poor health outcomes. Physiological stress is one mechanism thought to explain this pathway. We investigated associations between adversity and young children's health and whether child stress (measured using hair cortisol) mediated these associations.

METHODS

This was a cross-sectional study of 3-year-old children whose mothers were recruited during pregnancy, through the right@home trial, for their experience of adversity. Using total counts of 9 sociodemographic and 9 psychosocial indicators of adversity, regression models examined relationships among adversity risk counts, child hair cortisol (potential mediator), and 5 health outcomes: externalizing and internalizing problems, physical and socioemotional wellbeing, and overweight/obesity.

RESULTS

Hair cortisol data were available for 297 out of 500 (59%) participating children. When examined separately, sociodemographic adversity risk was associated with higher externalizing problems, and psychosocial adversity risk was associated with higher externalizing problems and poorer physical/socioemotional wellbeing. When examined together in a single model, psychosocial (but not sociodemographic) adversity was associated with higher externalizing problems (unstandardized mean difference [β], 0.53; P = .002) and poorer physical wellbeing (β, 1.19; P = .009); higher hair cortisol was associated with higher externalizing problems (β, 0.76; P = .02). There was no evidence that stress (hair cortisol) mediated associations between adversity and health.

CONCLUSIONS

In 3-year-old children, we found no evidence that physiological stress (hair cortisol) mediated associations between adversity risk and children's health. Hair cortisol may be limited as a single measure of stress, or physiological stress may not be a mechanism for explaining the effects of adversity on these young children's health.

Hair cortisol as a biomarker of stress and resilience in South African mixed ancestry females

BACKGROUND

Hair cortisol concentrations (HCC) are increasingly used as a biomarker of stress, however limited research exists regarding the relationship between HCC and protective factors, such as resilience. Additionally, studies measuring HCC need to account for possible confounders, and these factors have not been examined in sufficiently diverse settings.

OBJECTIVES

Our objectives were to identify determinants of HCC in a sample of mixed ancestry adults and investigate the association of HCC with measures of self-perceived stress and resilience.

METHODS

Our sample comprised 164 females (mean age 46.5 years, SD = 15.0), self-identifying as mixed ancestry, who were control participants in a case-control study (SHARED ROOTS), conducted in Cape Town, South Africa from May 2014 until June 2017. We examined which socio-demographic, hair related, clinical and behavioural factors were associated with HCC in both unadjusted and adjusted linear regression models. Furthermore, the relationship of HCC with self-perceived stress and resilience scores were also examined.

RESULTS

HCC (Mdn 4.4 pg/ml; IQR 2.8; 11.4) were significantly positively associated with hair product use and breastfeeding, and significantly negatively associated with age, level of education, duration of sun exposure, duration of storage, and demonstrated a trend towards significance with frequency of hair washing, in adjusted models. HCC were inversely associated with CD-RISC scores (adj β = -0.179, p =  0.012) but were not significantly associated with PSS scores (adj β = -0.001, p =  0.989).

CONCLUSIONS

We identified specific determinants of HCC in our sample, including the first indication that sun exposure has an effect on HCC under naturalistic conditions. These potential confounders need to be controlled for in the design and analysis of future studies. HCC may be a biomarker of resilience to stress, rather than perceived stress. Further research measuring HCC in more diverse settings and populations and including constructs related to resilience are needed.

Refugee mother-child dyads' hair cortisol, post-traumatic stress, and affectionate parenting

Refugees are a special population who experience adversity before, during and after forced displacement. Hence, many of them show post-traumatic stress symptoms (PTSS). PTSS can be transmitted from the mother to the child and are associated with alterations in cortisol responses. Positive parenting practices, such as maternal affection, counteracts psychopathology in early childhood. The aim of this explorative study was to investigate how children's cortisol is associated with mothers' cortisol after forced displacement, and whether or not an association depends on maternal affection. A total of 42 Arabic-speaking mother-child dyads, who came to Germany as refugees from Syria or Iraq within the past four years, participated in the present cross-sectional study. All children were below the age of 5 years. We assessed children's and mothers' hair cortisol concentration (HCC) and PTSS. Additionally, we observed and objectively rated maternal affection during mother-child interactions. The association between mothers' and children's HCC, as well as their associations with maternal affection, depended on the difference between children's and mothers' HCC. Furthermore, this HCC difference significantly predicted children's PTSS. Hence, in order to understand the mechanisms underlying children's PTSS, it is essential to consider maternal variables and differential effects within samples. We discussed possible explanations for those findings.

Hair cortisol, perceived stress, and social support in mother-child dyads living in an urban neighborhood

Women and children belonging to a racial/ethnic minority bear a disproportionate burden of psychosocial stress that increases their vulnerability to adverse health outcomes. Hair cortisol has been rapidly advanced as a biomarker of the intensity and course of the stress response over time and may provide an opportunity to increase our understanding of the role of psychological stress in health. However, research on the link between hair cortisol levels and subjective measures of maternal and child stress among low-income and minority individuals is limited. The goal of this study was to examine the association between stress and hair cortisol in low income, minority women and children who experience disproportionate exposure to chronic stress. A convenience sample of 54 minority mother/child dyads from a busy primary care clinic in the second poorest medium-sized city in the US participated in the study. Mothers self-reported perceived stress, social support, household characteristics and other demographic factors, and their children (ages 7-14 years) reported on the perceived level of safety in their neighborhood and exposure to violence as markers of child stress. Three-centimeter hair samples were collected from both mothers and children during the clinic visit, and hair cortisol levels were assessed via enzyme-linked immunosorbent assays. Linear regression models examined associations between maternal and child hair cortisol, and between hair cortisol and perceived stress level in women, and moderation by social support. Maternal hair cortisol was not significantly associated with mother's perceived stress. Maternal and child hair cortisol levels were positively associated (p = .007) but this association was not moderated by maternal perceived social support. These findings suggest that hair cortisol is strongly associated among this sample of minority mother-child dyads and is not moderated by social support.

Hair cortisol concentrations as an indicator of potential HPA axis hyperactivation in risk for psychosis

A chronic hyperactivation of the hypothalamic-pituitary-adrenal (HPA) axis is assumed to be an important indicator of vulnerability for psychosis. Despite the considerable research on this topic, putative social origins of HPA axis hyperactivation have received little attention in the literature so far. Also, the inconsistency of previous findings calls for new and reliable methods in the assessment of HPA axis activation. To address these issues, we used hair cortisol concentrations as an indicator of chronic HPA axis activation in participants at elevated risk for psychosis (clinical risk: n = 43, familial risk: n = 32) and low-risk controls (n = 35), and assessed its relation with a variety of social stressors. We also tested the interaction effect between social stressors and familial risk status on hair cortisol concentrations (moderation analysis). Participants at elevated risk for psychosis did not show significantly higher hair cortisol concentrations than low-risk controls. However, severe social stressors (child abuse experiences, traumatic events) predicted hair cortisol concentrations in the total sample. This relationship was not significantly moderated by familial risk status (as a marker of genetic risk). The results challenge the assumption that HPA axis hyperactivation is an early vulnerability indicator for psychosis but leave the possibility that it manifests only at more severe risk stages. Furthermore, the findings suggest that acquired experiences contribute to the emergence of HPA axis hyperactivation, which might occur via a gene-environment correlation rather than via a gene-environment interaction.

The effects of two early parenting interventions on child aggression and risk for violence in Brazil (The PIÁ Trial): protocol for a randomised controlled trial

BACKGROUND

Children in many low- and middle-income countries (LMICs) are at high risk for exposure to violence and later violent behaviour. The World Health Organization has declared an urgent need for the evaluation and implementation of low-cost parenting interventions in LMICs to prevent violence. Two areas of significant early risk are harsh parenting and poor child cognitive and socio-emotional development. Parenting interventions suitable for LMIC contexts have been developed targeting these risk factors and have been shown to have promising effects. However, their impact on child aggression, a key precursor of violence, has yet to be determined. The Pelotas Trial of Parenting Interventions for Aggression (PIÁ) has been designed to address this issue.

METHODS

We are conducting a randomised controlled trial to evaluate two early parenting interventions for mothers of children aged between 30 and 42 months in a Brazilian city. The first of these, dialogic book-sharing (DBS), aims to promote child cognitive and socio-emotional development; and the second, the ACT Raising Safe Kids Program (ACT), is designed to reduce harsh parenting. These interventions are being compared with a control group receiving neither intervention. Three hundred and sixty-nine families in a birth cohort are being randomly allocated to one of the three groups (DBS, ACT, Control). Facilitators deliver the interventions to groups of five to 10 mothers at weekly sessions for 8 weeks in DBS and 9 weeks in ACT. Independent assessments of parenting and child development are being made before the interventions, shortly afterwards, and at follow-up 6 months later. The primary outcome is child aggression, and the two main secondary outcomes are: (1) child cognitive and socio-emotional development and (2) harsh parenting. Longer-term outcomes will be investigated as the birth cohort is followed into late childhood, adolescence, and adulthood.

DISCUSSION

The Pelotas Trial of Parenting Interventions for Aggression (PIÁ) aims to evaluate the impact of two early parenting interventions on child aggression and several other key risk factors for the development of violence, including aspects of parenting and child cognition and socio-emotional functioning. The study is being carried out in a LMIC context where violence constitutes a major social and health burden. Since the two interventions are brief and, with modest levels of training, readily deliverable in LMIC settings, a demonstration that they benefit parenting and reduce risk factors for violence would be of major significance.

TRIAL REGISTRATION

Brazilian Ministry of Health Register of Clinical Trials, ID: RBR-2kwfsk . Registered on 6 June 2018.

The association between adversity and hair cortisol levels in humans: A meta-analysis

Adverse life events are associated with a constellation of negative health outcomes. Theory and research suggest that the hypothalamic-pituitary-adrenal (HPA) axis acts as one mechanism connecting adverse experiences with negative health outcomes. However, this relation is complicated by the potential for adversity to be associated with both hyperactivity and hypoactivity of the HPA axis, as assessed in both animal and human studies. Over the past decade, methodological advances have enabled the sampling of cortisol stored in hair, which provides a marker of HPA axis activity over a several-month period. The present meta-analysis included 28 studies to assess the strength and direction of the relation between adverse experiences and hair cortisol levels. Analyses were conducted using multilevel modeling (MLM) to quantify the magnitude of effects and mixture modeling to identify distinct subgroups of studies. Results of MLM analyses indicated that the overall effect size was small but significant d = 0.213, 95% CI [0.034, 0.397]. There was also significant between-study variance (τ = 0.155, 95% CI [0.065, 0.367]). Mixture modeling to identify distinct classes of studies based on effect size and direction resulted in a 2-class model: The first class included four studies with an overall negative and moderate effect size (d = -0.478, 95% CI [-0.639, -0.318]), and the second class included the remaining 24 studies with an overall positive and significant, albeit small, effect size (d = 0.141, 95% CI [0.084, 0.199]). Moderator analyses indicated that the strength and direction of the association between adversity and hair cortisol were moderated by features of the adversity exposure (e.g., type of adversity, timing of adversity), characteristics of the samples (e.g., clinical status, racial distribution), and features of the publication (e.g., publication type, geographic region of study). The findings refine our understanding of the long-term impact of adversity on dysregulation of the HPA axis, particularly as reflected in hair cortisol measures.

Hair cortisol, allostatic load, and depressive symptoms in Australian Aboriginal and Torres Strait Islander people

Chronic stress and adversity are associated with poor mental health and are thought to contribute to the existing mental health gap between Aboriginal and Torres Strait Islander people and other Australians. Hair cortisol and allostatic load (AL) are indices of sustained stress and may be mediators of the effects of stress on health. The aim of this study was to examine the relationship between hair cortisol, AL, and depressive symptoms. This cross-sectional study comprised 329 Aboriginal and Torres Strait Islander adolescents and adults recruited at two health screening programs operating in three communities in north Queensland. We measured hair cortisol and calculated an AL index from 10 biomarkers. We assessed depressive symptoms with a version of the Patient Health Questionnaire-9 adapted for Aboriginal and Torres Strait Islander people (aPHQ-9). We found differences in cortisol and AL between the screening programs and communities, which were not explained by depressive symptoms. Overall aPHQ-9 scores were unrelated to hair cortisol (p = .25 and p = .94) and AL (p = .30 and p = .88) when age, gender and smoking were taken into account. However, anhedonia (p = .007) and insomnia (p = .006) sub-scores were each significantly associated with AL in one study site. Our present data did not demonstrate overall associations of stress biomarkers and multisystem dysregulation with depressive symptoms, which suggests that the relationship between cumulative stress and depression may be better explained by other factors in this population. The specific association between anhedonia and insomnia with AL indicates that chronic multisystem dysregulation plays a role in these features of depression in this population. Lay summary Our study investigated the relationship between symptoms of depression and two biological pathways thought to mediate depression risk - the stress hormone cortisol and allostatic load (AL) - in an Australian Aboriginal and Torres Strait Islander population. Overall, cortisol and AL were unrelated to depression. However, AL was selectively associated with anhedonia (lack of motivation or drive) and sleep disturbances. These results suggest that metabolic dysregulation measured as AL may be relevant to the depression risk in this population.

Perceived stress and reference ranges of hair cortisol in healthy adolescents

Background

Chronic stress during adolescence has usually been evaluated through subjective measures, leaving aside objective measures such as hair cortisol concentrations. Therefore, the aim of this study was to provide reference ranges for hair cortisol concentrations by sex and age and to study the relationship between subjective and objective measures of stress and temporal stability.

Methods

The participants were 170 adolescents aged between 12 and 14 years (mean = 12.78 years; standard deviation = 0.71 years; 52.40% girls) who completed the Perceived Stress Scale 4 and had their hair sampled.

Results

The results revealed hair cortisol concentrations ranging from 0.07 pg/mg to 9.54 pg/mg. Subjective and objective measures of stress were not related, nor was there intraindividual stability of the hair cortisol concentrations. Girls had higher hair cortisol concentrations, and there were no age differences.

Conclusions

This research provides cortisol reference values for adolescents that will allow the early detection of chronic stress. Such detection methods make it possible to prevent problems arising from stress because we can act more quickly and the treatments will be more effective. The study suggests that there is no relationship between perceived and objective stress; while perceived stress remained stable, the levels of hair cortisol were increased at 6 months. Despite the interesting findings of the study, there are some limitations: the sample was not obtained through probabilistic sampling, the age range was narrow, and some demographic, anthropomorphic and clinical factors are missing, which make the generalization of results difficult.

Hair cortisol and cortisone as markers of stress in Indigenous and non-Indigenous young adults

Chronic, ongoing stress can impact negatively on health and wellbeing. Indigenous Australians are at an increased risk of experiencing multiple stressors. Hair glucocorticoids have been used as a marker for chronic stress. This study aimed to assess the associations of hair cortisol and cortisone with sociodemographic (age, gender, Indigenous Identification), substance use, emotional wellbeing, and emotional stress, in a cohort at increased risk of stressful events and psychological distress. Cross-sectional data (age 21-28 years) are presented from two Australian longitudinal studies; the Aboriginal Birth Cohort (n = 253) and non-Indigenous Top End Cohort (n = 72). A third of the cohort reported psychological distress, with Indigenous participants reporting higher rates of stressful events compared to non-Indigenous (6 vs. 1; p < .001). Significantly higher levels of cortisone were seen in Indigenous women compared to non-Indigenous women (β 0.21; p = .003). A positive association with age was present in hair cortisol and cortisone in Indigenous young adults (β 0.29 and β 0.41; p < .001, respectively). No association with substance use, emotional wellbeing or emotional stress was seen. Sub-analysis in women suggested a possible curvilinear relationship between hair cortisone and the number of stressful events. In this culturally diverse cohort, hair sampling provides a noninvasive, easily conducted and generally well tolerated mechanism to measure stress markers. The association with age, even in this narrow age range, likely represents the manifold changes in circumstances (financial independence, becoming parents, increased risk of substance use and mental illness) that occur during this transitional period of life, particularly for young Indigenous women. LAY ABSTRACT Chronic stress can impact negatively on health and emotional wellbeing. A hair sample is an easy way to measure chronic stress in Indigenous and non-Indigenous young people. The markers of chronic stress, cortisol and cortisone, were different between Indigenous and non-Indigenous, men and women and increased with age in Indigenous young adults.

Innovations in biological assessments of chronic stress through hair and nail cortisol: Conceptual, developmental, and methodological issues

Much of the existing research on biological mechanisms underlying the stress experience has focused largely on moment-to-moment stress, rather than on chronic stress, an arguably more powerful predictor of long-term outcomes. Recent methodological innovations have paved the way for new lines of research on chronic stress, with promising implications for developmental researchers and for those who study health and adversity. In particular, there are increasing studies that have focused on chronic stress assessments by relying on cortisol derived from hair and nails as a biomarker for chronic stress. In this paper, we provide an overview of their use, describe how hair and nail cortisol ought to be conceptualized differently across the lifespan, how developmental factors may impact its interpretation, and the circumstances under which its use may be more methodologically sensible. The purpose of this review is to provoke further discussion and encourage careful research designs that utilize hair and nail cortisol for understanding the effects of chronic stress exposure from the early developmental period, across adverse contexts, and in association with psychological and physical health outcomes.

Correlates of hair cortisol concentrations in disadvantaged young children

Children from highly disadvantaged families tend to experience worse health, educational, and job outcomes than less disadvantaged peers. However, the mechanisms underlying these relationships remain to be explicated. In particular, few studies have investigated the relationships between the psychosocial influences that children are exposed to early in life and longer term cortisol output. This study aims to contribute to the literature by exploring how disadvantaged young children's experiences of family adversity, and parenting and family functioning, are related to their long-term cortisol levels. A sample of 60 children (26 males, mean = 4.25 years, SD = 1.68) and their mothers (mean = 34.18 years, SD = 7.11) from a low-income population took part in a single assessment. Mothers completed questionnaires on the family environment, parenting practices, and child behaviour. Children provided a hair sample for cortisol assay and anthropometric measures. A parsimonious multivariate regression model (including potential predictors identified by a selection algorithm) was used to investigate the correlates of hair cortisol concentration (HCC) in children. Higher levels of social exclusion, being male, and younger age were each associated with higher HCC. Maternal nurturing and emotion coaching were associated with lower HCC. Findings suggest that chronic stress may underlie relationships between adversity and its long-term effects and that HCC offers a promising method for examining chronic stress in children and evaluating interventions by which it can be ameliorated.

Maternal experiences of trauma and hair cortisol in early childhood in a prospective cohort

BACKGROUND AND OBJECTIVE

Maternal trauma can have intergenerational consequences but little is known about whether maternal traumas affect key biological domains associated with mental health in their offspring. The objective of this study was to examine maternal lifetime history of traumatic events through mid-gestation in relation to offspring cortisol production in early childhood.

METHODS

The sample was comprised of 660 children (49.9% Black, 44.4% White) from a longitudinal study of mother-offspring dyads in Shelby County, Tennessee, followed from mid-gestation to child age 4 years (enrolled 2006-2011). Maternal lifetime history of traumatic life events were assessed mid-gestation using the Traumatic Life Events Questionnaire. Total cortisol output among offspring was measured using hair cortisol concentrations at ages 1 to 4 years.

RESULTS

Associations of maternal trauma history with child hair cortisol varied by child's age. No association was observed at age 1 or 2. In adjusted regression models, at ages 3 and 4, offspring of mothers in the third (β = 0.99, P < .01), fourth (β=0.72, P < .05), and fifth (β=0.83, P < .01) quintiles of trauma exposure history had elevated (natural log) hair cortisol concentrations, relative to mothers in the lowest quintile (P-trend = 0.003). The associations were not attenuated after adjustment for theorized pathways, including premature birth, maternal postpartum depression, and maternal parenting stress.

CONCLUSIONS

Maternal lifetime trauma exposures are associated with offspring hair cortisol concentrations. Future research is needed to determine intermediary mechanisms and functional significance of elevated hair cortisol concentration in young children.

Childhood maltreatment, pituitary volume and adolescent hypothalamic-pituitary-adrenal axis - Evidence for a maltreatment-related attenuation

BACKGROUND

Alterations of the development of the hypothalamic-pituitary-adrenal axis (HPAA) have been suggested to be related to experiences of early maltreatment. It has been postulated that early stress (i.e., maltreatment) leads to initial hyperactivation of the HPAA, which subsequently may progress to hypoactivation during the course of adolescence, however empirical studies on this hypothesis are rare. In the current study, we aimed to examine the longitudinal relationships between childhood maltreatment, early adolescent pituitary gland volume (PGV) and mid-adolescent cortisol output in an existing data set to explore the utility of PGV as a measure of HPAA function, and as an indirect test of the attenuation hypothesis.

METHODS

The sample comprised 69 adolescents (30 females), subsampled from a larger longitudinal, community-based study on adolescent development. PGV, as an estimate of chronic childhood HPAA activity, was measured by magnetic resonance imaging during early adolescence (mean age 12.62 ± 0.45 years). Cortisol output was assessed via multiple salivary cortisol measures in mid-adolescence (mean age 15.52 ± 0.39 years). The cortisol awakening response (CAR) was calculated as a measure of HPAA functioning. Retrospective assessment of childhood maltreatment was performed using the Childhood Trauma Questionnaire (CTQ). Regression analyses were conducted to examine whether childhood maltreatment, PGV, and their interaction, predicted mid-adolescent CAR.

RESULTS

No main effect of PGV or maltreatment was found on adolescent CAR. PGV did however significantly interact with childhood maltreatment in predicting the CAR (t = -2.26; p = 0.024). Larger PGV positively predicted lower CAR in the context of relatively high childhood maltreatment (t = 2.032; p = 0.046), but showed no relationship in the context of relatively low maltreatment (t = 0.723; p = 0.472). Maltreatment also interacted with sex, such that (only) in females, higher levels of maltreatment predicted a lower CAR (t = -2.04, p = 0.042).

CONCLUSIONS

In the presence of childhood maltreatment, larger PGV was associated with lower CAR in adolescence, providing support for the application of PGV in studies of HPA axis function. Our finding is consistent with a maltreatment-related attenuation of HPAA functioning that may derive from a stress induced chronic hyperactivation during childhood. Prospective longitudinal studies are now required to further explicate these findings and relationships with psychopathology.

Measurement of cortisol, dehydroepiandrosterone, and testosterone in the hair of children: Preliminary results and promising indications

Hormone analysis is a valuable tool for understanding how physiology and behavior interact. Cortisol in hair has recently been examined as a measure of longer-term hormone output. The aim of this study was to investigate the relationships between other androgens in hair and anthropometric measures. In a child sample (n = 114, mean age: 8.5 years, 66 females) levels of cortisol, dehydroepiandrosterone (DHEA) and testosterone were assayed in the 0-3 cm section proximal to scalp. The 3-6 cm segment within a subsample of female participants (n = 35) was examined and compared. Results showed that testosterone strongly correlated with DHEA, and moderately correlated with cortisol (0-3 cm only). Higher hormone concentrations were present in the 3-6 cm segment. Finally, there was a weak positive association between DHEA and height. The replication of previously identified associations between androgens, particularly testosterone-DHEA, and with developmental measures suggests hair may offer a valid method of hormone measurement for DHEA and testosterone.

Extending the developmental origins of disease model: Impact of preconception stress exposure on offspring neurodevelopment

The concept of the developmental origins of health and disease via prenatal programming has informed many etiologic models of health and development. Extensive experimental research in non-human animal models has revealed the impact of in utero exposure to stress on fetal development and neurodevelopment later in life. Stress exposure, however, is unlikely to occur de novo following conception, and pregnancy health is not independent of the health of the system prior to conception. For these reasons, the preconception period is emerging as an important new focus for research on adverse birth outcomes and offspring neurodevelopment. In this review, we summarize the existing evidence for the role of preconception stress exposure on pregnancy health and offspring neurodevelopment across species and discuss the implications of this model for addressing health disparities in obstetrics and offspring outcomes.

Associations of perceived stress with the present and subsequent cortisol levels in fingernails among medical students: a prospective pilot study

Purpose

Cortisol in fingernails could retrospectively reflect cumulative stress over a long period. However, the association between fingernail cortisol and perceived stress needs to be validated. This exploratory study aimed to investigate the associations of perceived stress with the present and subsequent cortisol levels in fingernails of the subjective stress measurement among medical students.

Methods

Students were recruited from a medical university in Shenyang, China. The final sample consisted of 51 students (16 men, 35 women). On the Day 30 of our data and fingernail collection procedure, the 10-item Perceived Stress Scale was used to measure perceived stress. Fingernail samples were collected twice, on Days 15 (denoted as FD15) and 45 (denoted as FD45) of the procedure, and participants were asked to grow fingernails for 15 days in each collection. Cortisol was determined by an enzyme immunoassay method using the ELISA kit. Multiple linear regression was performed to examine the association between perceived stress and cortisol level. The Bonferroni correction was made for multiple comparisons.

Results

The level of cortisol was 5.65 pg/mg (SD =1.88) for FD15 and 5.41 pg/mg (SD =1.63) for FD45. Perceived stress was not associated with the cortisol level of FD15 (β=−0.014, P=0.924), but it was significantly and positively associated with the cortisol level of FD45 (β=0.436, P=0.003), which remained significant after Bonferroni correction. The associations between fingernail cortisol and demographic variables (gender, age, BMI, and physical activity) were not significant.

Conclusion

This study was the first to investigate fingernail cortisol in China. Perceived stress was positively associated with the subsequent cortisol levels in fingernails, but not the present. The findings suggested that fingernail cortisol could indicate stress exposure in the past. Furthermore, a simple and easy self-reported measure could reflect cumulative stress as measured by fingernail cortisol.

Early child adversity and psychopathology in adulthood: HPA axis and cognitive dysregulations as potential mechanisms

Early adversity (EA) has been shown to be a potent risk factor for developing a psychopathology in adulthood. Alterations of the stress system in addition to changes in brain development have been suggested to explain some of the psychopathologies associated with EA. The stress response involves the activation of the hypothalamic-pituitary-adrenal (HPA)-axis, which leads to the production of glucocorticoids (GCs; cortisol in humans). Being soluble in lipids, GCs easily cross the blood brain barrier and access GC receptors in the hippocampus, prefrontal cortex and amygdala. These three brain structures do not develop at the same rhythm in humans and recent models suggest that exposition to EA at different times throughout cerebral development can induce a differential vulnerability to diverse mental illnesses. Although these models are of interest, they do not provide any mechanism(s) through which exposition to EA could lead to an increased vulnerability to certain mental illnesses and not others. Interestingly, the main brain structures that are affected by the chronic secretion of stress hormones during childhood (hippocampus, prefrontal cortex and amygdala) are differentially involved in various cognitive functions (memory, emotion regulation, encoding of emotional memories, etc.). It is therefore proposed that exposure to EA, by affecting the development of specific brain structures, might alter the underlying cognitive process of these brain regions, and increase vulnerability to specific mental disorders in adulthood.