Allostasis and the development of internalizing and externalizing problems: Changing relations with physiological systems across adolescence

Allostatic Load in Childhood, Adolescence, and Young Adulthood: Are Assumptions of Measurement Invariance Warranted?

OVERVIEW

Allostatic load represents the cumulative toll of chronic mobilization of the body's stress response systems, as indexed by biomarkers. Higher levels of stress and disadvantage predict higher levels of allostatic load, which, in turn, predict poorer physical and mental health outcomes. To maximize the efficacy of prevention efforts, screening for stress- and disadvantage-associated health conditions must occur before middle age-that is, during childhood, adolescence, and young adulthood. However, this requires that models of allostatic load display properties of measurement invariance across age groups. Because most research on allostatic load has featured older adults, it is unclear if these requirements can be met.

METHODS

To address this question, we fit a series of exploratory and confirmatory analytic models to data on eight biomarkers using a nationally representative sample of N = 4260 children, adolescents, and young adults drawn from the National Health and Nutrition Examination Survey dataset.

RESULTS

Exploratory and confirmatory models indicated that, consistent with allostatic load theory, a unidimensional model was a good fit to the data. However, this model did not display properties of measurement invariance; post-hoc analyses suggested that the biomarkers included in the final confirmatory model were most strongly intercorrelated among young adults and most weakly intercorrelated among adolescents.

CONCLUSIONS

These results underscore the importance of testing assumptions about measurement invariance in allostatic load before drawing substantive conclusions about stress, disadvantage, and health by directly comparing levels of allostatic load across different stages of development, while underscoring the need to expand investigations of measurement invariance to samples of longitudinal data.

Adrenocortical and autonomic cross-system regulation in youth: A meta-analysis

Childhood and adolescence are salient periods for the development of adrenocortical and autonomic arms of the stress response system (SRS), setting the stage for subsequent health and adaptive functioning. Although adrenocortical and autonomic systems theoretically function in highly coordinated ways, the strength of the relationship between these systems remains unclear. We leveraged a multivariate mixed effects meta-analytic approach to assess associations between adrenocortical, sympathetic, and parasympathetic functioning at rest and reactivity during stress-inducing tasks across 52 studies (N = 7,671; 5-20 years old). Results suggested a modest positive relation between adrenocortical and sympathetic systems as well as between adrenocortical and parasympathetic systems. Moderation analyses indicated the strength of associations varied as a function of several methodological and sociodemographic characteristics. Environmental effects on cross-system regulation were less clear, perhaps due to underrepresentation of adverse-exposed youth in the included studies. Collectively, our findings call for greater methodological attention to the dynamical, non-linear nature of cross-system functioning, as well as the role of experience in their organization across development.

Allostatic Load in Children and Adolescents: A Systematic Review

INTRODUCTION

The concept of allostatic load encompasses the cumulative effects of both ordinary daily life events as well as major challenges, and also includes related health-damaging behavior. Allostatic overload ensues when environmental challenges exceed the individual's ability to cope. Identification of allostatic load is carried out through the use of biomarkers and clinimetric criteria. Studies are increasingly reported on allostatic load in younger populations, yet a systematic review is missing.

OBJECTIVE

The aim of the present systematic review was to summarize the current knowledge on allostatic load/overload among children and adolescents.

METHODS

PubMed, PsycINFO, Web of Science, and the Cochrane Library were searched from inception to April 2023. A manual search of the literature was also performed. We considered only studies in which allostatic load or overload were adequately described and assessed in either clinical or non-clinical populations younger than 18 years.

RESULTS

A total of 38 original investigations were included in this systematic review. Studies reported an association between allostatic load and sociodemographic characteristics (e.g., poverty, ethnicity, perceived discrimination, adverse childhood experiences) and environmental factors, as well as consequences of allostatic load on both physical and mental health among children and adolescents.

CONCLUSIONS

The findings indicate that greater allostatic load is associated with poorer health outcomes in both clinical and non-clinical pediatric populations, with possible enduring effects. The results support the clinical utility of the transdiagnostic identification of allostatic load and overload in children and adolescents across a variety of settings, with a number of potential clinical implications.

Mexican-origin youths' language brokering for fathers and mothers: Daily experiences and youths' diurnal cortisol slopes

This study examined the associations of language brokering stress intensity and exposure with Mexican-origin youths' cortisol responses when brokering for fathers and mothers, and the moderating role of youths' brokering efficacy in these relations. Participants were 289 adolescents (Mage  = 17.38, SD = .94, 52% girls) in immigrant families. When brokering for mothers, stress exposure was related to flatter (less healthy) same-day diurnal slopes in youth. When brokering for fathers, daily brokering efficacy buffered the detrimental link between stress intensity and youths' same-day cortisol slopes. When brokering for fathers/mothers, stress intensity and exposure were related to flatter (less healthy) next-day diurnal slopes. Although daily brokering stress can relate to youth physiologic functioning, feeling efficacious about brokering may buffer the negative ramifications of stress.

Evaluating measures of allostatic load in adolescents: A systematic review

BACKGROUND

Adolescents can experience heightened stress due to biopsychosocial changes that occur during this developmental stage. The 'wear and tear' of the physiological systems responsible for managing our stress response can lead to dysregulation of these systems, known as allostatic load (AL). AL is commonly measured within adult populations, however, inconsistencies exist across measures used to quantify the effects of stress on health. The aim of this review was to identify variations in measures across AL studies, and to consider how specific measures may be more appropriate for use within adolescent populations.

METHOD

Pubmed, PsycINFO, PsycARTICLES, Academic Search Complete, were searched in July 2020, using search terms 'allostatic load' and 'adolescence'. AL studies (1988-2020) with an adolescent population (age 10-24 years) were included. 354 records were screened by two reviewers and 41 full-text articles were assessed for eligibility.

RESULTS

25 studies were included in final synthesis. Biomarkers of AL ranged from 1 to 14. The most common index of AL consisted of 6 biomarkers; cortisol, epinephrine, norepinephrine, systolic blood pressure, diastolic blood pressure, and body-mass index.

FINDINGS

Defining measures of AL during adolescence may help to identify vulnerabilities specific to adolescents, which may shape their lifelong health trajectories.

Associations between autonomic nervous system activity and risk-taking and internalizing behavior in young adolescents

Dysregulated autonomic nervous system (ANS) activity has been associated with adolescent risk‐taking and internalizing behavior, but previous results in community samples have been mixed. We investigated whether ANS activity was associated with higher risk‐taking and internalizing behavior in young adolescents (age 11/12; n = 875), and whether adolescents' gender, parents' parenting style or a combination of both moderated these associations. Adolescents and their parents were recruited as part of the population‐based, longitudinal Amsterdam Born Children and their Development (ABCD) study. Risk‐taking behavior was assessed with the Balloon Analogue Risk Task and the personality characteristics sensation seeking and impulsivity, measured with the Substance Use Risk Profile Scale (SURPS). Internalizing behavior was assessed via the SURPS subscales anxiety sensitivity and hopelessness. Authoritative (AUTH‐SW) and authoritarian (AUTH‐S) parenting styles were measured with the Parenting Styles and Dimensions Questionnaire. Resting ANS activity was assessed via heart rate and respiratory sinus arrhythmia (RSA). Hierarchical, multivariable regression analyses showed higher RSA, but not heart rate, being associated with higher risk‐taking behavior and sensation seeking. The associations between ANS activity and risk‐taking variables were not significantly moderated by gender, parenting, or interactions between gender and parenting. Our findings suggest that RSA activity may be a relevant factor in mild to moderate risk‐taking behavior in adolescents from the general population, regardless of their gender or the type of parenting they experience.

Dysregulated autonomic nervous system activity has been associated with adolescent risk‐taking and internalizing behavior, but previous results in community samples have been mixed. Our findings suggest that in adolescents from the general population, respiratory sinus arrhythmia activity may be a relevant factor in mild to moderate risk‐taking behavior but not in internalizing behavior, regardless of adolescents' gender or the type of parenting they experience.

Are All Purposes Worth Having? Integrating Content and Strength in Purpose Research

A prevailing belief is that a sense of purpose in life is worth having, based on evidence that it predicts greater psychological functioning, social relationships, physical health, and longevity. Yet, whether the benefits of having a sense of purpose persist across all contents – or the actual substance of one’s aspirations – lingers as a critical blind spot within this literature. Here, we contend that an ecological systems perspective is needed to contextualize how purpose content either enables or extinguishes the benefits of feeling purposeful. We nominate congruence (the fit between a purpose and ecological conditions) and feasibility (the ease with which a purpose can be pursued) as measurable features of purpose content that fuse people and contexts and potentiate whether a sense of purpose proves favorable. Greater congruence and feasibility should orchestrate support for purpose-related goals, actions, and justifications, thus amplifying the likelihood of positive outcomes. Practical strategies for integrating the congruence and feasibility of individuals’ aspirations within the study of purpose are discussed.

[LIFE Child Depression - a prospective longitudinal cohort study on the origin of depressive disorders between childhood and early adulthood]

LIFE Child Depression - a prospective longitudinal cohort study on the origin of depressive disorders between childhood and early adulthood LIFE Child Depression is a prospective longitudinal study on the origin and course of depressive symptoms and disorders between child- and adulthood. The aim of the study is to identify patterns of developmental courses of symptoms and disorders and to investigate the interplay of psychosocial, biological and genetic risk and protective factors in the development of depressive disorders. The present paper gives an overview on results of the study. The sample was already assessed three times. A clinical sample was recruited from two local child psychiatric in- and outpatient services in Leipzig, a control sample was recruited from a children's health check program at our medical faculty (LIFE Child Health) and from the local registration office. We found some important context- and parent-associated risk factors for depressive disorders, such as negative life events, low socioeconomic status and depression in mothers (but not in fathers). Moreover, we found some characteristic biological and cognitive-emotional characteristics of children with depressive disorders, such as low stress-related cortisol, low evaluation of own performance, and more negative cognitions in dealing with stressful situations, low self-esteem and a general impairment of emotional processing of human faces. Only some of the risk factors were found to be specific to depression. Instead, most of them can be regarded as general risk factors for psychological disorders in childhood. It is also noteworthy, that some of the risk associations were gender-specific and need to be looked at from a differential point of view. Our study gives important indications for prevention for children at risk for depressive disorders as well as for therapeutic approaches.

Associations between multisystem stress reactivity and peer nominated aggression in early childhood vary by sex

There is emerging evidence that the development of problematic aggression in childhood may be associated with specific physiological stress response patterns, with both biological overactivation and underactivation implicated. This study tested associations between sex-specific patterns of stress responses across the sympathetic nervous system (SNS) and hypothalamic-pituitary-adrenal (HPA) axis and peer nominations of aggression among 271 kindergarten children (Mean age = 5.32 years; 52% Female; 44% White). Upon entry to kindergarten, children participated in a multidomain standardized stress paradigm. Changes in pre-ejection period (PEP) and salivary cortisol were assessed. On a separate day, children provided peer ratings of physical and relational aggression in a standardized interview. As expected, there was a significant three-way interaction between PEP, cortisol reactivity, and sex, but only for physical aggression. Among boys, cortisol reactivity was positively associated with physical aggression only for those with higher SNS reactivity. Findings suggest that for boys, asymmetrical and symmetrical HPA/SNS reactivity may be associated with lower and higher risk for peer-directed physical aggression, respectively. Understanding the complex associations between multisystem physiology, child sex and peer-directed aggression in early childhood may offer insight into individual differences underlying the emergence of behavioral dysregulation in early peer contexts.

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.

Challenges to Identity Integration Indirectly Link Experiences of Heterosexist and Racist Discrimination to Lower Waking Salivary Cortisol in Sexually Diverse Latinx Emerging Adults

Heterosexist and racist discrimination may adversely impact neurobiological processes implicated in the physical and psychosocial well-being of sexually diverse Latinx people. Yet, little is known about how experiences of both heterosexist and racist discrimination are associated with adrenocortical and psychological functioning in groups of people with multiply marginalized social group identities. Through the application of the intersectionality, minority stress, and allostatic load frameworks, it was hypothesized that experiences of heterosexist and racist discrimination would be associated with disruptions to diurnal salivary cortisol patterns and challenges to identity integration. A group of sexually diverse (self-identified lesbian, gay, bisexual, and queer) Latinx emerging adults (N = 51; ages 18-29, M = 24.06 years; SD = 2.73) provided saliva samples and completed a series of questionnaires during a four-day testing protocol. Heterosexist and racist discrimination were both positively associated with challenges to identity integration. Challenges to identity integration, in turn, were associated with lower intercepts of diurnal cortisol slopes, and heterosexist and racist discrimination were indirectly associated with lower cortisol intercepts via challenges to identity integration. These findings suggest that experiences of heterosexist and racist discrimination may interconnect by challenging sexual and ethnic/racial identity integration and disrupting adaptive adrenocortical regulation among sexually diverse Latinx emerging adults.

Co-activation of SAM and HPA responses to acute stress: A review of the literature and test of differential associations with preadolescents' internalizing and externalizing

Understanding co-activation patterns of the hypothalamic-pituitary-adrenal axis (HPA) and sympathetic adrenal medullary (SAM) during early adolescence may illuminate risk for development of internalizing and externalizing problems. The present study advances empirical work on the topic by examining SAM-HPA co-activation during both the reactivity and recovery phases of the stress response following acute stress exposure. Fourth and fifth grade boys and girls (N = 149) provided cortisol and alpha-amylase via saliva at seven times throughout a 95-min assessment in which they were administered the modified Trier Social Stress Test. Parents reported on adolescents' life stress, pubertal development, medication use, and externalizing problems. Adolescents reported their own internalizing symptoms. Multiple linear regressions tested both direct and interactive effects of SAM and HPA reactivity and recovery on internalizing and externalizing problems. Results from these analyses showed that whereas SAM and HPA reactivity interacted to predict internalizing symptoms, it was their interaction during the recovery phase that predicted externalizing. Concurrent high SAM and HPA reactivity scores predicted high levels of internalizing and concurrently low SAM and HPA recovery scores predicted high levels of externalizing. Implications of the findings for further study and clinical application are discussed.

Chronicity of mental comorbidity in children with new-onset physical illness

BACKGROUND

Evidence suggests that physical and mental illnesses are strongly correlated in children. This study examined patterns of the chronicity of multimorbidity (co-occurring physical and mental illness); estimated homotypic continuity; and modelled factors associated with chronicity in children newly diagnosed with a chronic physical illness.

METHODS

Children aged 6-16 years diagnosed with one of asthma, diabetes, epilepsy, food allergy, or juvenile arthritis were recruited from two children's hospitals and followed for 6 months. Child mental illness was measured using the parent-reported Mini International Neuropsychiatric Interview and Ontario Child Health Study Emotional Behavioural Scales at baseline and 6 months later. Children were stratified into three groups: no multimorbidity, acute (multimorbidity at only one assessment), and persistent (multimorbidity at both assessments).

RESULTS

Forty-nine children were available for analysis: no multimorbidity (n = 18), acute (n = 13), and persistent (n = 18). Homotypic continuity was highest for conduct disorder (67.5%) and lowest for major depression (16.7%). Unadjusted analyses showed positive associations between child and parent behavioural symptoms, as well as family functioning with persistent multimorbidity. These associations remained after adjustment, ranging from odds ratio (OR) = 1.29 [1.01, 1.64] for depression to OR = 1.61 [1.11, 2.33] and OR = 1.61 [1.10, 2.35] for attention-deficit hyperactivity and oppositional defiant, respectively, in child models. In parent models, associations remained for parental anxiety (OR = 1.18 [1.04, 1.34]) and stress (OR = 1.15 [1.02, 1.31]).

CONCLUSIONS

Multimorbidity is persistent in children newly diagnosed with physical illnesses, regardless of the mental comorbidity experienced. Integrating family-centred mental health services soon after the diagnosis of a physical illness should be prioritized in pediatric settings.

Parental depression moderates the relationships of cortisol and testosterone with children's symptoms

BACKGROUND

Previous research on the hormone-symptom relationship in children suggests that certain hormone patterns may be associated with symptoms, but only under certain circumstances. Having a parent with a history of depression may be one circumstance under which dysregulated hormone patterns are especially associated with emotional and behavioral symptoms in children. The current study sought to explore these relationships in a community sample of 389 9-year-old children.

METHODS

Children's salivary cortisol and testosterone levels were collected at home over three consecutive days; parental psychiatric histories were assessed using semi-structured diagnostic interviews; and children's internalizing and externalizing symptoms were rated by the child's mother.

RESULTS

Having two parents with a history of depression moderated the associations of reduced total daily cortisol output with higher externalizing scores, as well as the association of reduced testosterone with higher internalizing scores. A maternal history of depression, on the other hand, moderated the relationship between higher cortisol awakening response and higher internalizing scores. Furthermore, lower daily cortisol output was associated with higher internalizing scores among girls, but not boys, with two parents with a history depression.

LIMITATIONS

Limitations include the cross-sectional nature of the current analyses, as well as the limited racial, ethnic, and geographical diversity of the sample.

CONCLUSIONS

Taken together, the current results suggest that the relationship between hormones and internalizing and externalizing symptoms in children may vary as a function of parental depression and child sex, knowledge that may inform intervention efforts aimed at preventing psychopathology in children whose parents have a history of depression.

Parasympathetic Regulation and Inhibitory Control Predict the Development of Externalizing Problems in Early Childhood

The current report examined the longitudinal relations between cognitive self-regulation, physiological self-regulation, and externalizing problems. At age 4 (n = 98; 49 girls) and 6 (n = 87; 42 girls), children completed the Day-Night task, which taps the inhibitory control dimension of executive function. During the task, cardiac activity was measured and respiratory sinus arrhythmia (RSA) was derived as an index of parasympathetic activity. Mothers reported on externalizing problems. A cross-lagged path model was used to estimate longitudinal predictions while controlling for stability in all constructs over time. Earlier inhibitory control negatively predicted later externalizing problems, but not vice versa. However, RSA reactivity moderated this link; better inhibitory control predicted fewer externalizing problems only when reactivity to the Day-Night task ranged from mild RSA suppression to RSA augmentation. Externalizing problems at 6 years were highest among preschoolers who augmented RSA but showed poor inhibitory control performance, suggesting that risk for psychopathology may be better delineated by viewing self-regulation from an integrated, multi-system perspective.

Cortisol stress reactivity moderates the effects of parental corporal punishment on Chinese preschoolers' executive function

BACKGROUND

To date whether the effects of parental corporal punishment (CP) on executive function (EF) distinct components are different is less clear. Moreover, theory and empirical work suggest that physiological regulation system may help to explain the individual differences in the developmental outcomes associated with parental CP.

OBJECTIVE

This study examined the effects of parental CP on Chinese preschoolers' EF and whether the cortisol stress reactivity would moderate such effects.

PARTICIPANTS AND SETTING

One hundred and fifty-two preschool-aged children and their parents from Beijing China participated in the present study.

METHODS

Parental CP was reported by fathers and mothers respectively in the first year of the study (2015, spring), and children's EF was assessed and salivary cortisol was collected in the second year (2016, spring).

RESULTS

Both paternal and maternal CP were negatively correlated with children's EF one year later, and the relation between maternal, but not paternal CP and children's EF was moderated by cortisol stress reactivity. Specifically, compared to children with high cortisol stress reactivity levels, children with low cortisol stress reactivity levels who experienced maternal CP in the past year showed poorer global EF and working memory.

CONCLUSIONS

Findings highlight the critical importance of examining the interactive effects of individual physiological level and environmental-level risks on young children's self-regulation outcomes.

The role of bicultural adaptation, familism, and family conflict in Mexican American adolescents' cortisol reactivity

Scarce research has examined stress responsivity among Latino youths, and no studies have focused on the role of acculturation in shaping cortisol stress response in this population. This study assessed Mexican American adolescents' Mexican and Anglo cultural orientations and examined prospective associations between their patterns of bicultural orientation and hypothalamic-pituitary-adrenal cortisol reactivity to an adapted Trier Social Stress Test. The sample included 264 youths from a longitudinal birth cohort study who completed the Trier Social Stress Test and provided saliva samples at age 14. The youths completed assessments of cultural orientation at age 12, and family conflict and familism at age 14. Analyses testing the interactive effects of Anglo and Mexican orientation showed significant associations with cortisol responsivity, including the reactivity slope, peak levels, and recovery, but these associations were not mediated by family conflict nor familism values. Findings revealed that bicultural youth (high on both Anglo and Mexican orientations) showed an expected pattern of high cortisol responsivity, which may be adaptive in the context of a strong acute stressor, whereas individuals endorsing only high levels of Anglo orientation had a blunted cortisol response. Findings are discussed in relation to research on biculturalism and the trade-offs and potential recalibration of a contextually responsive hypothalamic-pituitary-adrenal axis for acculturating adolescents.

Homotypic and heterotypic continuity of internalizing and externalizing symptoms from ages 3 to 12: The moderating role of diurnal cortisol

Psychological symptoms that arise in early childhood can follow a multitude of patterns into adolescence, including homotypic continuity (i.e., similar symptoms over time) and heterotypic continuity (i.e., a shift in symptoms over time). However, we know very little about the factors that distinguish homotypic vs. heterotypic continuity of early internalizing and externalizing symptoms over development. In a separate line of research, diurnal cortisol has been shown to predict later internalizing and externalizing problems. In the current study, we tested whether diurnal cortisol patterns moderated the course of internalizing and externalizing symptoms from preschool to early adolescence. 554 children (54% male) and parents participated in a longitudinal study. Parents reported on their children's internalizing and externalizing symptoms at ages 3 and 12, and children collected diurnal saliva samples at age 9. Results showed that a steeper cortisol decline at age 9 combined with high internalizing or externalizing problems at age 3 predicted higher internalizing problems at age 12. A more blunted cortisol decline combined with early internalizing or externalizing problems predicted higher externalizing problems in early adolescence. These results illustrate the moderating role of stress system functioning in homotypic and heterotypic patterns of psychopathology from preschool to early adolescence.

How children's anxiety symptoms impact the functioning of the hypothalamus-pituitary-adrenal axis over time: A cross-lagged panel approach using hierarchical linear modeling

Anxiety symptoms in childhood and adolescence can have a long-term negative impact on mental and physical health. Although studies have shown dysregulation of the hypothalamus-pituitary-adrenal axis is associated with anxiety disorders, it is unclear how and in what direction children's experiences of anxiety symptoms, which include physiological and cognitive-emotional dimensions, impact the functioning of the hypothalamus-pituitary-adrenal axis over time. We hypothesized that higher physiological symptoms would be contemporaneously associated with hypercortisolism, whereas cognitive-emotional symptoms would be more chronic, reflecting traitlike stability, and would predict hypocortisolism over time. One hundred twenty children from the Concordia Longitudinal Risk Research Project were followed in successive data collection waves approximately 3 years apart from childhood through midadolescence. Between ages 10-12 and 13-15, children completed self-report questionnaires of anxiety symptoms and provided salivary cortisol samples at 2-hr intervals over 2 consecutive days. The results from hierarchical linear modeling showed that higher physiological symptoms were concurrently associated with hypercortisolism, involving cortisol levels that remained elevated over the day. In contrast, longitudinal results over the 3 years between data collection waves showed that chronic worry and social concerns predicted hypocortisolism, showing a low and blunted diurnal cortisol profile. These results have implications for broadening our understanding of the links between anxiety, the stress response system, and health across the course of development.

Annual Research Review: Early adversity, the hypothalamic-pituitary-adrenocortical axis, and child psychopathology

BACKGROUND

Research on early adversity, stress biology, and child development has grown exponentially in recent years.

FINDINGS

We review the current evidence for the hypothalamic-pituitary-adrenocortical (HPA) axis as a stress-mediating mechanism between various forms of childhood adversity and psychopathology. We begin with a review of the neurobiology of the axis and evidence for relations between early adversity-HPA axis activity and HPA axis activity-psychopathology, as well as discuss the role of regulatory mechanisms and sensitive periods in development.

CONCLUSIONS

We call attention to critical gaps in the literature to highlight next steps in this research including focus on developmental timing, sex differences, stress buffering, and epigenetic regulation. A better understanding of individual differences in the adversity-HPA axis-psychopathology associations will require continued work addressing how multiple biological and behavioral systems work in concert to shape development.

Person-centered examination of salivary cortisol and alpha-amylase responses to psychosocial stress: Links to preadolescent behavioral functioning and coping

This study adopted a person-centered approach to identify preadolescent salivary cortisol (sC) and alpha-amylase (sAA) co-activation response patterns and examine links to behavioral functioning and coping. Children (N = 151, 51.7% male) were exposed to the Trier Social Stress Test (TSST) and one of two randomly-assigned, post-TSST coping conditions: distraction or avoidance. Multi-trajectory modeling yielded four child subgroups. Child internalizing and externalizing positively predicted High sC-High sAA relative to Low sC-Low sAA and Low sC-High sAA relative to High sC-Low sAA subgroup membership, respectively. Low sC-Low sAA children demonstrated more efficient sC recovery when primed with distraction and more protracted sC recovery when primed with avoidance. For High sC-High sAA, internalizing children, the opposite was true. Findings illustrate adjustment-linked variability in preadolescent sC-sAA co-activation response patterns that further articulates for whom effortful coping works to effectively manage stressor-induced neuroendocrine activation.

Endocrinological and subjective stress responses in children with depressive, anxiety, or externalizing disorders

In this study, we used a stress test to investigate endocrinological and subjective stress responses of 8- to 14-year-old children with internalizing or externalizing disorders and healthy controls. The sample (N = 170) consisted of clinical and community children. Parents were given a diagnostic interview to diagnose their children's psychiatric condition. We measured saliva cortisol and subjectively experienced arousal in children before and after the Trier Social Stress Test for Children. Children also rated their performance immediately after the stress test, and 1 hr later they rated their positive and negative thoughts about this stressful event. Children with internalizing or externalizing disorders exhibited a blunted cortisol response compared to healthy controls. Depressed children rated their test performance lower and reported more negative thoughts after the test in comparison to healthy controls, anxious children reported more arousal before and after the task, and children with externalizing disorders reported more positive thoughts. In regression analyses, cortisol and subjective stress responses were both predictive of psychiatric disorders. The study extends previous work on the relation between psychiatric disorders and children's stress responses to an experimentally induced stress task by including a broad range of psychiatric disorders and by integrating endocrinological and subjective stress responses.

Exploring the bio-behavioural link between stress, allostatic load & micronutrient status: A cross-sectional study among adolescent boys

Background & objectives:

Allostatic load (AL) is a cumulative measure of physiological deregulation and is influenced by multiple factors including nutrition. The objectives of the study were to assess AL among adolescent boys (15-19 yr) and delineate its association with psychological stress and micronutrient status.

Methods:

A cross-sectional, school-based study was conducted among 370 adolescent boys of five higher secondary schools from Hyderabad, India. Perceived stress, adolescent life event stress (ALES), psychological morbidity and coping were measured. Biomarkers of AL included dehydroepiandrosterone sulphate, 12-h urinary cortisol, interleukin-6, C-reactive protein, lipid profile, body mass index and blood pressure. Micronutrient status with respect to iron (haemoglobin, ferritin, hepcidin, soluble transferrin receptor), folate, vitamins B12, C and A were analyzed in a sub-sample of 146 boys. AL score ≥3 was calculated from eight biomarkers.

Results:

Fourteen per cent participants had no AL but 34.3 per cent had AL score of ≥ 3. Unadjusted means of ALES scores were significantly different (P = 0.045) among participants with low [mean, 95% confidence interval (CI): 580, 531-629] and high (663, 605-721) AL. After controlling for confounders, the means were significantly different for controllable life event sub-scale of ALES (P = 0.048). Adjusted hepcidin concentrations were significantly higher among participants with high AL (means, 95% CI, 27.2, 24.0-30.8 for high AL; 22.1, 20.2-24.2 μg/l for low AL, P = 0.014).

Interpretation & conclusions:

Build-up of AL was found in adolescent boys and was positively associated with life event stress. Iron nutrition and stress exhibited a positive association through hepcidin. The study provides a link between iron nutrition, physiological deregulation and stress.

Neurobiological stress responses predict aggression in boys with oppositional defiant disorder/conduct disorder: a 1-year follow-up intervention study

To improve outcome for children with antisocial and aggressive behavior, it is important to know which individual characteristics contribute to reductions in problem behavior. The predictive value of a parent training (Parent Management Training Oregon; PMTO), parenting practices (monitoring, discipline, and punishment), and child neurobiological function (heart rate, cortisol) on the course of aggression was investigated. 64 boys with oppositional defiant disorder or conduct disorder (8-12 years) participated; parents of 22 boys took part in PMTO. All data were collected before the start of the PMTO, and aggression ratings were collected three times, before PMTO, and at 6 and 12 month follow-up. Parent training predicted a decline in aggression at 6 and 12 months. Child neurobiological variables, i.e., higher cortisol stress reactivity and better cortisol recovery, also predicted a decline in aggression at 6 and 12 months. Heart rate and parenting practices were not related to the course of aggression. These results indicate that child neurobiological factors can predict persistence or reduction of aggression in boys with ODD/CD, and have unique prognostic value on top of the parent training effects.

Perceived Discrimination, Racial Identity, and Multisystem Stress Response to Social Evaluative Threat Among African American Men and Women

OBJECTIVE

Understanding individual differences in the psychobiology of the stress response is critical to grasping how psychosocial factors contribute to racial and ethnic health disparities. However, the ways in which environmentally sensitive biological systems coordinate in response to acute stress is not well understood. We used a social-evaluative stress task to investigate coordination among the autonomic nervous system, hypothalamic-pituitary-adrenal axis, and immune/inflammatory system in a community sample of 85 healthy African American men and women.

METHODS

Six saliva samples, 2 at each of baseline, event, and recovery phases of the stressor task, were assayed for cortisol, dehydroepiandrosterone-sulfate, salivary alpha-amylase, and salivary C-reactive protein. Individual differences in perceived discrimination and racial identity were also measured.

RESULTS

Factor analysis demonstrated that stress systems were largely dissociated before stressor exposure but became aligned during event and recovery phases into functional biological stress responses (factor loadings ≥ .58). Coordinated responses were related to interactions of perceived discrimination and racial identity: when racial identity was strong, highly perceived discrimination was associated with low hypothalamic-pituitary-adrenal axis activity at baseline (B's = .68-.72, p < .001), low stress mobilization during the task (B's = .46-.62, p < .049), and a robust inflammatory response (salivary C-reactive protein) during recovery (B's = .72-.94, p < .002).

CONCLUSION

Culturally relevant social perceptions may be linked to a specific pattern of changing alignment in biological components of the stress response. Better understanding these links may significantly advance understanding of stress-related illnesses and disparities.

Adolescent Conflict Appraisals Moderate the Link Between Marital Conflict and Physiological Stress Reactivity

The goal of this study was to advance understanding of how adolescent conflict appraisals contribute uniquely, and in combination with interparental conflict behavior, to individual differences in adolescent physiological reactivity. Saliva samples were collected from 153 adolescents (52% female; ages 10-17 years) before and after the Trier Social Stress Test. Saliva was assayed for cortisol and alpha-amylase. Results revealed interactive effects between marital conflict and conflict appraisals. For youth who appraised parental conflict negatively (particularly as threatening), negative marital conflict predicted dampened reactivity; for youth who appraised parental conflict less negatively, negative marital conflict predicted heightened reactivity. These findings support the notion that the family context and youth appraisals of family relationships are linked with individual differences in biological sensitivity to context.

The role of anxiety in cortisol stress response and cortisol recovery in boys with oppositional defiant disorder/conduct disorder

Children with antisocial and aggressive behaviors have been found to show abnormal neurobiological responses to stress, specifically impaired cortisol stress reactivity. The role of individual characteristics, such as comorbid anxiety, in the stress response is far less studied. Furthermore, this study extended previous studies in that not only baseline and reactivity to a psychosocial stressor were examined, but also recovery from a stressor. These three phases of cortisol could be impacted differentially in boys with oppositional defiant disorder/conduct disorder (ODD/CD) with (+ANX) and without anxiety (-ANX). The results revealed that cortisol patterns in response to psychosocial stress were different for boys with ODD/CD+ANX (n=32), ODD/CD-ANX (n=22) and non-clinical controls (NC) (n=34), with age range of 7.8-12.9 years. The ODD/CD-ANX group showed lower overall cortisol levels than the NC group. When considering the three phases of cortisol separately, the ODD/CD-ANX group had lower baseline cortisol levels relative to the other groups, whereas the ODD/CD+ANX showed an impaired cortisol recovery response. Within those with ODD/CD, callous-unemotional traits were predictive of high baseline cortisol levels. Also, anxiety predicted high baseline and recovery cortisol levels, whereas a high number of CD symptoms predicted reduced cortisol stress reactivity. These results clearly indicate that comorbid anxiety is an important factor in explaining differences in stress response profiles in boys with ODD/CD; although boys with CD/ODD are generally characterized by an impaired cortisol stress response, we found that those with comorbid anxiety showed impaired cortisol recovery, whereas those without anxiety showed reduced baseline cortisol levels.

Differential relations between youth internalizing/externalizing problems and cortisol responses to performance vs. interpersonal stress

Efforts to define hypothalamic-pituitary-adrenal (HPA) axis profiles conferring risk for psychopathology have yielded inconclusive results, perhaps in part due to limited assessment of the stress response. In particular, research has typically focused on HPA responses to performance tasks, while neglecting the interpersonal stressors that become salient during adolescence. In this study we investigated links between psychosocial adjustment - youth internalizing and externalizing problems, as well as competence - and HPA responses to both performance and interpersonal stressors in a normative sample of children and adolescents. Participants (n = 59) completed a set of performance (public speaking, mental arithmetic, mirror tracing) and/or interpersonal (peer rejection) tasks and gave nine saliva samples, which were assayed for cortisol. Hierarchical linear models of cortisol response trajectories in relation to child behavior checklist (CBCL) scores revealed stressor- and sex-specific associations. Whereas internalizing problems related to earlier peaking, less dynamic cortisol responses to interpersonal stress (across males and females), externalizing problems related to lower, earlier peaking and less dynamic cortisol responses to performance stress for males only, and competence-related to later peaking cortisol responses to interpersonal stress for females only. Implications for understanding contextual stress profiles underlying different forms of psychopathology are discussed.

Coordination of cortisol response to social evaluative threat with autonomic and inflammatory responses is moderated by stress appraisals and affect

Recent approaches to stress regulation have emphasized coordination among multiple biological systems. This study builds on evidence that hypothalamic-pituitary-adrenal (HPA) axis activity should be considered in coordination with other stress-sensitive biological systems to characterize healthy responses. Healthy African-Americans (n=115) completed the Trier Social Stress Test, and biological responses were assessed through salivary cortisol, dehydroepiandrosterone-sulfate (DHEA-S), alpha amylase (sAA), and C-reactive protein (sCRP). Multilevel modeling demonstrated that cortisol responses typically aligned with changes in DHEA-S, sAA, and sCRP across the session. At the same time, the degree of cortisol coordination with sAA and sCRP varied by participants' subjective stress following the task; participants with higher secondary stress appraisals showed greater cortisol-sAA alignment, whereas those experiencing more negative affect showed greater cortisol-sCRP alignment. Results highlight the importance of a multisystem approach to stress and suggest that positive HPA axis coordination with the autonomic response, but not with the immune/inflammatory response, may be adaptive.

Dispositional and Environmental Predictors of the Development of Internalizing Problems in Childhood: Testing a Multilevel Model

This investigation evaluated a multilevel model of dispositional and environmental factors contributing to the development of internalizing problems from preschool-age to school-age. In a sample of 375 families (185 daughters, 190 sons) drawn from three independent samples, preschoolers' behavioral inhibition, cortisol and gender were examined as moderators of the links between mothers' negative parenting behavior, negative emotional characteristics, and socioeconomic status when children were 3.95 years, and their internalizing problems when they were 8.34 years. Children's dispositional characteristics moderated all associations between these environmental factors and mother-reported internalizing problems in patterns that were consistent with either diathesis-stress or differential-susceptibility models of individual-environment interaction, and with gender models of developmental psychopathology. Greater inhibition and lower socioeconomic status were directly predictive of more teacher reported internalizing problems. These findings highlight the importance of using multilevel models within a bioecological framework to understand the complex pathways through which internalizing difficulties develop.

Early childhood cortisol reactivity moderates the effects of parent-child relationship quality on the development of children's temperament in early childhood

Positive parenting has been related both to lower cortisol reactivity and more adaptive temperament traits in children, whereas elevated cortisol reactivity may be related to maladaptive temperament traits, such as higher negative emotionality (NE) and lower positive emotionality (PE). However, no studies have examined whether hypothalamic-pituitary-adrenal axis activity, as measured by cortisol reactivity, moderates the effect of the quality of the parent-child relationship on changes in temperament in early childhood. In this study, 126 3-year-olds were administered the Laboratory Temperament Assessment Battery (Lab-TAB; Goldsmith et al., 1995) as a measure of temperamental NE and PE. Salivary cortisol was collected from the child at 4 time points during this task. The primary parent and the child completed the Teaching Tasks battery (Egeland et al., 1995), from which the quality of the relationship was coded. At age 6, children completed the Lab-TAB again. From age 3 to 6, adjusting for age 3 PE or NE, a better quality relationship with their primary parent predicted decreases in NE for children with elevated cortisol reactivity and predicted increases in PE for children with low cortisol reactivity. Results have implications for our understanding of the interaction of biological stress systems and the parent-child relationship in the development of temperament in childhood.

Neuroendocrine coupling across adolescence and the longitudinal influence of early life stress

Drawing on conceptual models illustrating the advantages of a multisystemic, interactive, developmental approach to understanding development, the present study examines the covariation of stress and sex hormones across the adolescent transition and the effect of early life stress (ELS) on neuroendocrine coupling to gain insight into atypical development. Morning levels of cortisol, testosterone, and dehydroepiandrosterone (DHEA) were assessed at ages 11, 13, and 15; ELS was assessed during the infancy and preschool periods. Hierarchical linear modeling revealed that cortisol-DHEA coupling patterns progressed to tight, positive coupling across adolescence. Cortisol-testosterone coupling was positive at age 11 but became more negative at ages 13 and 15. Exposure to ELS resulted in more adultlike neuroendocrine coupling patterns earlier in life than non-exposed youth; however the effect of ELS on cortisol-testosterone coupling was unique to girls. Results illustrate trajectories of neuroendocrine coupling that may be unique to adolescence. Moderation by ELS suggests that early stress exposure may prompt earlier adultlike neuroendocrine coupling, particularly within girls, which may contribute to early pubertal development.

Regulating sadness and fear from outside and within: mothers' emotion socialization and adolescents' parasympathetic regulation predict the development of internalizing difficulties

Multilevel models of developmental psychopathology implicate both characteristics of the individual and their rearing environment in the etiology of internalizing problems and disorders. Maladaptive regulation of fear and sadness, the core of anxiety and depression, arises from the conjoint influences of ineffective parasympathetic regulation of emotion and ineffective emotion socialization experiences. In 171 youths (84 female, M = 13.69 years, SD = 1.84), we measured changes of respiratory sinus arrhythmia (RSA) in response to sadness- and fear-inducing film clips and maternal supportive and punitive responses to youths' internalizing emotions. Youths and mothers reported on youths' internalizing problems and anxiety and depression symptoms concurrently and 2 years later at Time 2. Maternal supportive emotion socialization predicted fewer, and punitive socialization predicted more, mother-reported internalizing problems at Time 2 only for youths who showed RSA suppression to fear-inducing films. More RSA suppression to sadness-inducing films predicted more youth-reported internalizing problems at Time 2 in girls only. In addition, less supportive emotion socialization predicted more youth-reported depression symptoms at Time 2 only for girls who showed more RSA suppression to sadness. RSA suppression to sadness versus fear might reflect different patterns of atypical parasympathetic regulation of emotional arousal, both of which increase the risk for internalizing difficulties in youths, and especially girls, who lack maternal support for regulating emotions.

A dual-axis approach to understanding neuroendocrine development

This introduction sets out to present a series of paper about a novel perspective regarding stress and sex hormones, or what the authors within this special issue term "coupling" of hypothalamic-pituitary-adrenal and--gonadal axes. This view postulates that these axes do not necessarily operate in opposition, but can operate together as evidenced empirically as a positive within-person association between stress hormones like cortisol or sex hormones like testosterone. A wealth of papers within the special issue demonstrate positive coupling across acute, diurnal, basal, and longitudinal timeframes and across several different types of contexts. Reviews were meant to challenge whether this was physiologically plausible. Consistently, sophisticated statistical models were utilized in order to show a template for how to model positive coupling and to ensure that coupling was a within-person phenomenon. We cautiously considered positive coupling until the consistency of observing coupling was robust enough for us to consider challenging the prevailing oppositional view of these axes. We do so to acknowledge that there are contexts, moments and stages in which the function of these axes should work together: for example when contexts are both stressful and challenging or at developmental stages (like adolescence) in which the youth must grow up despite the storm and stress of youth. We hope that by putting forward a functional dual-axis approach, the field will be able to consider when and how these axes work together.

Relational victimization, friendship, and adolescents' hypothalamic-pituitary-adrenal axis responses to an in vivo social stressor

Adolescents' peer experiences may have significant associations with biological stress-response systems, adding to or reducing allostatic load. This study examined relational victimization as a unique contributor to reactive hypothalamic-pituitary-adrenal (HPA) axis responses as well as friendship quality and behavior as factors that may promote HPA recovery following a stressor. A total of 62 adolescents (ages 12-16; 73% female) presenting with a wide range of life stressors and adjustment difficulties completed survey measures of peer victimization and friendship quality. Cortisol samples were collected before and after a lab-based interpersonally themed social stressor task to provide measures of HPA baseline, reactivity, and recovery. Following the stressor task, adolescents discussed their performance with a close friend; observational coding yielded measures of friends' responsiveness. Adolescents also reported positive and negative friendship qualities. Results suggested that higher levels of adolescents' relational victimization were associated with blunted cortisol reactivity, even after controlling for physical forms of victimization and other known predictors of HPA functioning (i.e., life stress or depressive symptoms). Friendship qualities (i.e., low negative qualities) and specific friendship behaviors (i.e., high levels of responsiveness) contributed to greater HPA regulation; however, consistent with theories of rumination, high friend responsiveness in the context of high levels of positive friendship quality contributed to less cortisol recovery. Findings extend prior work on the importance of relational victimization and dyadic peer relations as unique and salient correlates of adaptation in adolescence.

The symphonic structure of childhood stress reactivity: patterns of sympathetic, parasympathetic, and adrenocortical responses to psychological challenge

Despite widespread recognition that the physiological systems underlying stress reactivity are well coordinated at a neurobiological level, surprisingly little empirical attention has been given to delineating precisely how the systems actually interact with one another when confronted with stress. We examined cross-system response proclivities in anticipation of and following standardized laboratory challenges in 664 4- to 14-year-olds from four independent studies. In each study, measures of stress reactivity within both the locus coeruleus-norepinephrine system (i.e., the sympathetic and parasympathetic branches of the autonomic nervous system) and the corticotrophin releasing hormone system (i.e., the hypothalamic-pituitary-adrenal axis) were collected. Latent profile analyses revealed six distinctive patterns that recurred across the samples: moderate reactivity (average cross-system activation; 52%-80% of children across samples), parasympathetic-specific reactivity (2%-36%), anticipatory arousal (4%-9%), multisystem reactivity (7%-14%), hypothalamic-pituitary-adrenal axis specific reactivity (6%-7%), and underarousal (0%-2%). Groups meaningfully differed in socioeconomic status, family adversity, and age. Results highlight the sample-level reliability of children's neuroendocrine responses to stress and suggest important cross-system regularities that are linked to development and prior experiences and may have implications for subsequent physical and mental morbidity.

Pubertal maturation and cortisol level in response to a novel social environment among female adolescents

Research indicates changes in HPA-axis activity across puberty. The current study extends existing work by evaluating pubertal status and cortisol level in a novel social environment (research laboratory) while controlling for several important biological, behavioral, and psychological variables. Participants were 30 girls (ages 9-16 years) from the United States. Pubertal status was assessed via the Pubertal Development Scale. Salivary samples were collected at laboratory-introduction and a matched at-home period; laboratory-introduction levels were regressed on basal cortisol levels to create standardized residual scores. After controlling for covariates, pubertal status was positively associated with residualized cortisol values. Findings indicate more advanced puberty related to greater cortisol response to the laboratory; data are discussed in terms of future research and building biopsychosocial models of the puberty-psychopathology linkage.

Within-adolescent coupled changes in cortisol with DHEA and testosterone in response to three stressors during adolescence

It is hypothesized that hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes function together to maintain adaptive functioning during stressful situations differently in adolescence than the characteristic inverse relations found in adulthood. We examined within-person correlated changes (coupling) in cortisol, DHEA and testosterone in response to parent-adolescent conflict discussion, social performance, and venipuncture paradigms. Data are derived from two samples of boys and girls from the Northeastern US (213 adolescents aged 11-16, M=13.7, SD=1.5 years; 108 adolescents aged 9-14, M=11.99, SD=1.55) using different biological sampling vehicles (saliva and blood). Results consistently show that across samples, vehicles, and contexts, cortisol and DHEA and cortisol and testosterone are positively coupled in response to environmental stimuli. Findings underscore the importance of considering the effects of multiple hormones together in order to further our understanding of the biological underpinnings of behavior, especially during adolescence, as adolescence is a developmental transition period that may be qualitatively different from adulthood in terms of hormone functioning.

Hormones: commentary. Riding the physiological roller coaster: adaptive significance of cortisol stress reactivity to social contexts

The authors conjecture that to understand normal stress regulation, including cortisol stress reactivity, it is important to understand why these biomarkers are released and what they function to accomplish within the individual. This perspective holds that high (or rising) cortisol has advantages and disadvantages that must be understood within a context to understand how individual differences unfold. This perspective is juxtaposed with a popular vantage point of this stress hormone or of stress exposure that emphasizes the deleterious consequences or problems of this hormone. While the costs and benefits of cortisol are emphasized for normal stress regulation, this dynamic context-dependent purpose of stress hormones should extend to the development of psychopathology as well. This functional and dynamic view of cortisol is helpful for interpreting why Tackett and colleagues (2014) appear to observe advantageous cortisol recovery from stress in individuals with elevated personality disorder symptoms.

Beyond allostatic load: Rethinking the role of stress in regulating human development

How do exposures to stress affect biobehavioral development and, through it, psychiatric and biomedical disorder? In the health sciences, the allostatic load model provides a widely accepted answer to this question: stress responses, while essential for survival, have negative long-term effects that promote illness. Thus, the benefits of mounting repeated biological responses to threat are traded off against costs to mental and physical health. The adaptive calibration model, an evolutionary–developmental theory of stress–health relations, extends this logic by conceptualizing these trade-offs as decision nodes in allocation of resources. Each decision node influences the next in a chain of resource allocations that become instantiated in the regulatory parameters of stress response systems. Over development, these parameters filter and embed information about key dimensions of environmental stress and support, mediating the organism's openness to environmental inputs, and function to regulate life history strategies to match those dimensions. Drawing on the adaptive calibration model, we propose that consideration of biological fitness trade-offs, as delineated by life history theory, is needed to more fully explain the complex relations between developmental exposures to stress, stress responsivity, behavioral strategies, and health. We conclude that the adaptive calibration model and allostatic load model are only partially complementary and, in some cases, support different approaches to intervention. In the long run, the field may be better served by a model informed by life history theory that addresses the adaptive role of stress response systems in regulating alternative developmental pathways.

Asymmetry in children's salivary cortisol and alpha-amylase in the context of marital conflict: links to children's emotional security and adjustment

Recent research supports the promise of examining interactive models of physiological processes on children's adjustment. The present study investigates interactions between children's autonomic nervous system activity and adrenocortical functioning in the context of marital discord; specifically, testing models of concurrent responses proposed by Bauer et al. ([2002] Developmental and Behavioral Pediatrics 23:102-113) in the prediction of children's behavioral responses to conflict and adjustment. Asymmetry and symmetry in children's salivary alpha-amylase and cortisol were examined in 195 children (M age = 8 years) in response to viewing conflict vignettes. Results were partially consistent with an interactive model in the context of high marital discord; asymmetry among higher alpha-amylase and lower cortisol related to higher emotional insecurity and concurrent and subsequent maladjustment. In contrast, patterns of symmetrical responses were related to greater maladjustment for children exposed to lower levels of marital discord, supporting an additive model. Findings support the importance of a multisystem approach to investigating the adaptiveness of children's physiological stress responses, while also highlighting the value of considering physiological responses in the context of family risk.

Psychopathy's influence on the coupling between hypothalamic-pituitary-adrenal and -gonadal axes among incarcerated adolescents

Conduct disorder (CD) is a heterogeneous diagnosis, leading researchers to initiate studies focused on neurobiological mechanisms underlying this disorder. One specifier of CD currently considered for inclusion in the DSM-V is callous-unemotional (CU) traits, a key component of psychopathy. CU traits are thought to have neuroendocrine underpinnings, yet little is known about hypothalamic-pituitary-adrenal (HPA) and -gonadal (HPG) hormones in the context of psychopathic traits. The current study sought to identify daily coupling patterns between HPA and HPG hormones in order to clarify distinct neurobiological underpinning associated with psychopathic/CU traits. Fifty incarcerated adolescent males who met criteria for CD were recruited and provided 10 saliva samples across 2 days. Participants completed the Psychopathy Checklist Youth Version (PCL:YV) and Inventory of Callous Unemotional Traits (ICU) on a third day. Diurnal cortisol, testosterone, and DHEA functioning was modeled via hierarchical linear modeling. Psychopathy subscales from the measures administered were used as predictors of daily coupling patterns between these hormones. Results indicated all three hormones were tightly coupled. Further, higher PCL-YV interpersonal scores related to greater coupling between all three hormones, whereas higher ICU callousness scores related to greater uncoupling of testosterone with cortisol and DHEA. The current study is novel in its emphasis on testing the coupling of HPA and HPG hormones among incarcerated adolescent males. Results suggest that affective and interpersonal psychopathic traits are marked by unique HPA- and HPG coupling.

Neighborhood disorder and telomeres: connecting children's exposure to community level stress and cellular response

Our objective was to explore the utility of salivary telomere length (sTL) as an early indicator of neighborhood-level social environmental risk during child development. We therefore tested the hypothesis that sTL would be associated with markers of social stress exposure in children. Children age 4-14 from 87 neighborhoods were recruited through five urban schools in New Orleans, Louisiana, U.S. Data were collected at the level of the child, family/household, and neighborhood. DNA was obtained from saliva using commercially available kits and sTL was determined for 104 children using quantitative PCR. Analysis was performed on 99 children who had complete data including sTL, social environmental stress, and additional covariates. The mean sTL value was 7.4 T/S (telomere signal/single-copy signal) ratio units (±2.4, range = 2.5-18.0), and 4.7% of the variance in sTL was attributed to differences across neighborhoods. Children living in neighborhoods characterized by high disorder had an sTL value 3.2 units lower than children not living in high disordered environments (p < 0.05) and their odds of having low relative sTL (defined as <1 standard deviation below standardized Z-score mean) values was 3.43 times that of children not living in high disorder environments (adjusted OR = 3.43, 95% CI = 1.22, 9.62). Our findings are consistent with previous studies in adults demonstrating a strong link between psychosocial stress and sTL obtained from peripheral blood, consistent with previous studies in youth demonstrating an association between early life stress and sTL obtained from buccal cell DNA and offer increased support for the hypothesis that sTL represents a non-invasive biological indicator of psychosocial stress exposure (i.e., neighborhood disorder) able to reflect differences in stress exposure levels even in young children.