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.

Maternal prenatal lead levels and neonatal brain volumes: Testing moderations by maternal depressive symptoms and family income.

There is considerable evidence that prenatal lead exposure is detrimental to child cognitive and socio-emotional development. Further evidence suggests that the effects of prenatal lead on developmental outcomes may be conditional upon exposure to social stressors, such as maternal depression and low socioeconomic status. However, no studies have examined associations between these co-occurring stressors during pregnancy and neonatal brain volumes. Leveraging a sample of 101 mother-infant dyads followed beginning in mid-pregnancy, we examined the main effects of prenatal urinary lead levels on neonatal lateralized brain volumes (left and right hippocampus, amygdala, cerebellum, frontal lobes) and total gray matter. We additionally tested for moderations between lead and depressive symptoms and between lead and family income relative to the federal poverty level (FPL) on the same neurodevelopmental outcomes. Analyses of main effects indicated that prenatal lead was significantly (ps < 0.05) associated with reduced right and left amygdala volumes (ßs = -0.23- -0.20). The testing and probing of cross-product interaction terms using simple slopes indicated that the negative effect of lead on the left amygdala was conditional upon mothers having low depressive symptoms or high income relative to the FPL. We interpret the results in the context of trajectories of prenatal and postnatal brain development and susceptibility to low levels of prenatal lead in the context of other social stressors.

The Mood, Mother and Child Study: Protocol for a Prospective Longitudinal Study and Randomized Controlled Trial.

BACKGROUND: Perinatal depression affects >400,000 mother-child dyads in the United States every year and is associated with numerous adverse maternal and child developmental outcomes. Previous research implicates the dysregulation of oxytocin and the hypothalamic-pituitary-adrenal (HPA) axis functioning in mothers and children as potential mechanisms mediating or moderating the transmission of risk associated with maternal depression. OBJECTIVE: The Mood, Mother and Child study will examine the psychobiological sources of risk and resilience within mother-child dyads affected by maternal depression. This manuscript describes (1) the study rationale and aims, (2) the research design and procedures and how they were altered in response to the COVID-19 pandemic, and (3) the data analysis plan to test the study hypotheses. METHODS: This is a prospective longitudinal study with an embedded randomized controlled trial that examines (1) correlations among postpartum depression and anxiety symptoms, maternal and child oxytocin and HPA axis functioning, and child developmental outcomes and (2) the causal relationship between exogenous oxytocin and HPA reactivity. This study is funded by the National Institute of Child Health and Human Development with institutional review board approval. RESULTS: Recruitment and data collection have commenced, and the expected results will be available in 2024. Analyses are presented for testing the proposed hypotheses. CONCLUSIONS: The unique combination of a prospective longitudinal research design with an embedded randomized controlled trial will allow the Mood, Mother and Child study to apply a developmental lens to the study of maternal depression and anxiety symptoms from birth to middle childhood and the psychobiological mechanisms promoting risk and resiliency for both mother and child outcomes. This will be the first study that simultaneously evaluates (1) the role of oxytocin using multiple methodologies, (2) the causal relationships between exogenous oxytocin and HPA axis functioning among mothers with differing levels of depression and anxiety symptoms, and (3) the multiple mediating and moderating roles of parenting behaviors and maternal and child psychobiological characteristics. The goals of these aims are to provide insights into the psychobiological effects of oxytocin in women and inform future clinical trials to treat perinatal mood disorders. TRIAL REGISTRATION: ClinicalTrials.gov NCT03593473; https://classic.clinicaltrials.gov/ct2/show/NCT03593473. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/51132.

Vagal Flexibility Moderates the Links between Observed Sensitive Caregiving in Infancy and Externalizing Behavior Problems in Middle Childhood.

This study explored how patterns of physiological stress reactivity underpin individual differences in sensitivity to early rearing experiences and childhood risk for psychopathology. To examine individual differences in parasympathetic functioning, past research has largely relied on static measures of stress reactivity (i.e., residual and change scores) in infancy which may not adequately capture the dynamic nature of regulation across contexts. Using data from a prospective longitudinal study of 206 children (56% African Americans) and their families, this study addressed these gaps by employing the latent basis growth curve model to characterize the dynamic, non-linear patterns of change in infants' respiratory sinus arrhythmia (i.e., vagal flexibility) across the Face-to-Face Still-Face Paradigm. Furthermore, it investigated whether and how infants' vagal flexibility moderates the links between sensitive parenting, observed during a free play task when children were 6 months of age, and parent-report of children's externalizing problems at 7 years of age. Results of the structural equation models revealed that infants' vagal flexibility moderates the predictive relations between sensitive parenting in infancy and children's later externalizing problems. Simple slope analyses revealed that low vagal flexibility, characterized by less suppression and flatter recovery patterns, exacerbated risk for externalizing psychopathology in the context of insensitive parenting. Children with low vagal flexibility also benefited most from sensitive parenting, as indicated by the lower number of externalizing problems. Findings are interpreted in the light of the biological sensitivity to context model and provide evidence for vagal flexibility as a biomarker of individual's sensitivity to early rearing contexts.

Sexual Minority Stressors and Intimate Partner Violence Among Same-Sex Couples: Commitment as a Resource.

Accumulating evidence has been found for the associations from sexual minority stressors to intimate partner violence (IPV) among same-sex couples. Yet key gaps still exist, including the rare utilization of couple dyadic data, the understudied moderating and mediating mechanisms, and the few studies conducted during the transitional period of same-sex marriage legalization. To address these gaps, we used cross-sectional, dyadic data collected from 144 US same-sex couples during the 2014-2015 national campaign for the legalization of same-sex marriage. Guided by the systemic transactional model (STM), we examined associations from sexual minority stressors (including both internalized homophobia and discrimination) to same-sex IPV and tested whether commitment moderated or mediated these associations. Overall, we found evidence supporting the STM: (1) High internalized homophobia and discrimination were related to high prevalence and/or frequency of IPV perpetration; (2) high commitment attenuated positive associations between high discrimination and high prevalence and/or frequency of IPV perpetration; and (3) high internalized homophobia was related to low commitment, which in turn was related to high prevalence and/or frequency of IPV perpetration. Collectively, our study identified commitment as both a moderator and mediator in associations from sexual minority stressors to same-sex IPV. Further, the roles of commitment (i.e., moderator or mediator) depend on whether the focal sexual minority stressors are distal and more intermittent (i.e., heterosexist discrimination) or proximal and more constant (i.e., internalized homophobia).

Parenting and maternal reported child sleep problems in infancy predict school-age aggression and inattention.

OBJECTIVE: To examine caregiving predictors of maternal reported sleep problems and child behavioral and cognitive outcomes in early childhood. DESIGN: A prospective longitudinal study from 6 to 84 months of age. SETTING: Lab visits, assessments, and questionnaires conducted with a community-based sample. PARTICIPANTS: One hundred sixty-four African American and White children, their mothers, and teachers. MEASUREMENT: Parenting behavior was measured during a free-play task at 6 months of age, maternal-report of child sleep problems was completed at 6 timepoints, and teacher report of child aggression and attention was collected in kindergarten and second grade. RESULTS: Latent growth curve modeling revealed that maternal reported sleep problems decreased in children from 18 to 84 months and harsh-intrusive parenting at 6 months predicted sleep problems at 18 months. Maternal reported sleep problems at 18 months predicted aggressive behaviors in kindergarten and second grade. CONCLUSION: Parenting at 6 months of age exerts an influence on sleep quality at 18 months which is associated with aggressive behavior in early childhood.

Profiles of family-based social experiences in the first 3 years predict early cognitive, behavioral, and socioemotional competencies.

This study utilized latent profile analyses to identify unique configurations of children's family-based social experiences during the first 3 years of life and examine differences across profiles with respect to developmental outcomes at 36 and 48 months of age. Seven family process variables were used: maternal emotional functioning, maternal sensitivity, negative controlling parenting, cognitive stimulation, corporal punishment, adult-adult aggression, and household disorganization. Data were collected by the Family Life Project (N = 1,087), a longitudinal study of families living in low-wealth, nonurban areas, for whom the biological mother was the child's primary caregiver from 6 to 36 months of age. On average, mothers were 26 years of age at 2 months of child age. Approximately 36% of the families lived below the federal poverty limit, and 41% identified as Black; 49% of children were female. Latent profile analyses identified four groups: (a) positive exposure (b) average exposure, (c) problematic adult functioning, and (d) problematic parenting . Comparisons indicate that children in the positive exposure profile had the highest levels of socioemotional and cognitive outcomes compared to overall profiles. Children in the problematic adult functioning and problematic parenting profiles had the most problematic child outcomes, with children in the problematic parenting profile scoring lowest overall. Results indicate that there is configural heterogeneity in family-based social experiences at the highest levels of risk and that exposures to problematic parenting may be more consequential for later child outcomes than exposures to problematic adult functioning in the absence of compromised caregiving. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Attachment quality assessed from children's family drawings links to child conduct problems and callous-unemotional behaviors.

OBJECTIVE: Recently, there has been considerable research on the origins of childhood conduct problems (CP) and callous-unemotional (CU) behaviors. This study examined associations between children's attachment representations and CP and CU behaviors during middle childhood. METHOD: At 1st grade, 1,292 children (57% European American, 42.5% African American, 0.5% other race; 50.9% girls) completed a drawing of their family, which was coded by trained raters to assess attachment representations. Primary caregivers reported on children's CP and CU behaviors. RESULTS: Children with disorganized representations showed more CP and CU behaviors than children with secure and resistant representations. They were also more likely than those with secure representations to show elevated CP without CU behaviors, CU behaviors only, and co-occurring CP and CU behaviors. CONCLUSION: These findings provide support for attachment disorganization as a correlate of CP and CU behaviors and suggest that attachment representations are likely important proximal influences on children's behavior.

Towards an understanding of neurophysiological self-regulation in early childhood: A heuristic and a new approach.

Self-regulation in early childhood encompasses both "top down," volitional processes, as well as the "bottom up" activity of three neurophysiological systems: the parasympathetic nervous system (PNS), the sympathetic nervous system (SNS), and the hypothalamic-pituitary-adrenal (HPA) axis. In this paper we briefly review the structure, function, and early development of each of these systems and then explain why neurophysiological self-regulation is most accurately defined as a function of their joint activity. We note that while there are a number of predictive models that employ this definition, the field would benefit from a straightforward heuristic and aligned methods of visualization and analysis. We then present one such heuristic, which we call neurophysiological space, and outline how it may facilitate a new, collaborative approach to building a better understanding of self-regulation in early childhood. We conclude with a presentation of early education as one setting in which our heuristic and methods could be applied.

The neurophysiological embedding of child maltreatment.

Maltreatment adversely impacts the development of children across a host of domains. One way in which maltreatment may exert its deleterious effects is by becoming embedded in the activity of neurophysiological systems that regulate metabolic function. This paper reviews the literature regarding the association between childhood maltreatment and the activity of three systems: the parasympathetic nervous system, the sympathetic nervous system, and the hypothalamic-pituitary-adrenal axis. A particular emphasis is placed on the extent to which the literature supports a common account of activity across these systems under conditions of homeostasis and stress. The paper concludes with an outline of directions for future research and the implications of the literature for policy and practice.

Poverty, Caregiving, and HPA-Axis Activity in Early Childhood.

The association between poverty and the activity of the hypothalamic pituitary adrenal (HPA) axis in early childhood is well established. Both ecological and transactional theories suggest that one way in which poverty may influence children's HPA-axis activity is through its effects on parents' behaviors, and over the past three decades a substantial literature has accumulated indicating that variations in these behaviors are associated with individual differences in young children's HPA-axis activity. More recent research suggests that non-parental caregiving behaviors are associated with HPA-axis activity in early childhood as well. Here we systematically review the literature on the association between both parental and non-parental caregiving behaviors in the context of poverty and the activity of the HPA-axis in early childhood. We conclude by noting commonalities across these two literatures and their implications for future research.

Early life predictors of attention deficit/hyperactivity disorder symptomatology profiles from early through middle childhood.

This study used repeated measures data to identify developmental profiles of elevated risk for ADHD (i.e., six or more inattentive and/or hyperactive-impulsive symptoms), with an interest in the age at which ADHD risk first emerged. Risk factors that were measured across the first 3 years of life were used to predict profile membership. Participants included 1,173 children who were drawn from the Family Life Project, an ongoing longitudinal study of children's development in low-income, nonmetropolitan communities. Four heuristic profiles of ADHD risk were identified. Approximately two thirds of children never exhibited elevated risk for ADHD. The remaining children were characterized by early childhood onset and persistent risk (5%), early childhood limited risk (10%), and middle childhood onset risk (19%). Pregnancy and delivery complications and harsh-intrusive caregiving behaviors operated as general risk for all ADHD profiles. Parental history of ADHD was uniquely predictive of early onset and persistent ADHD risk, and low primary caregiver education was uniquely predictive of early childhood limited ADHD risk. Results are discussed with respect to how changes to the age of onset criterion for ADHD in DSM5 may affect etiological research and the need for developmental models of ADHD that inform ADHD symptom persistence and desistance.

Parenting and Cortisol in Infancy Interactively Predict Conduct Problems and Callous-Unemotional Behaviors in Childhood.

This study examines observed maternal sensitivity, harsh-intrusion, and mental-state talk in infancy as predictors of conduct problems (CP) and callous-unemotional (CU) behaviors in middle childhood, as well as the extent to which infants' resting cortisol and cortisol reactivity moderate these associations. Using data from the Family Life Project (n = 1,292), results indicate that maternal sensitivity at 6 months predicts fewer CP at first grade, but only for infants who demonstrate high levels of cortisol reactivity. Maternal harsh intrusion predicts fewer empathic-prosocial behaviors, a component of CU behaviors, but only for infants who demonstrate high resting cortisol. Findings are discussed in the context of diathesis-stress and differential susceptibility models.

The Significance of Parenting and Parent-Child Relationships for Sexual and Gender Minority Adolescents.

Adolescents in 21st century America are experiencing the emergence of their sexual and gender identities in a heteronormative society that is steadily adopting more progressive views and policies related to sexual orientation and gender. However, despite these sociocultural changes, parent-child relationships remain as one of the strongest predictors of LGBT adolescent adjustment. This article reviews the extant literature on this topic from family systems and attachment perspectives while highlighting the significance of family experiences within a minority stress framework. The presentation is oriented around the coming out process, including factors influencing this experience and how postdisclosure parenting affects the health and well-being of LGBT adolescents. We end by discussing future directions and the challenges inherent to this research.

Otitis media and respiratory sinus arrhythmia across infancy and early childhood: Polyvagal processes?

Otitis media (OM)-or middle-ear inflammation-is the most widely diagnosed childhood illness, with evidence implicating OM in a range of distal problems (e.g., language delays, attention problems). Polyvagal theory (Porges, 1995, 2007) posits that there also are likely important connections between middle-ear functioning and children's developing parasympathetic nervous systems (PNS). Using prospective longitudinal data from the Family Life Project (n = 748), we tested within- and between-person relations between indicators of OM (middle-ear spectral gradient angle; SGA) and children's trajectories of respiratory sinus arrhythmia (RSA)-a marker of parasympathetic control of the heart-between the ages of 7 and 35 months. The results suggested that, irrespective of age, children with indications of chronic OM (low cumulative SGA) tended to show atypical RSA reactivity to moderate cognitive challenge, compared with the reactivity patterns of their low-OM-risk peers (mid-to-high cumulative SGA). Specifically, on average, low-OM-risk children showed RSA decreases in the context of challenge in infancy, with the magnitude of the decline weakening and eventually changing direction (i.e., RSA increase) by 35 months. In contrast, those with indicators of chronic OM evinced blunted RSA responses to challenge, irrespective of age. Within-person, temporal bouts of OM-risk were not predictive of within-person changes in RSA reactivity across early childhood. (PsycINFO Database Record

Sociodemographic risk, parenting, and inhibitory control in early childhood: the role of respiratory sinus arrhythmia.

BACKGROUND: Deficits of inhibitory control in early childhood are linked to externalizing behaviors and attention problems. While environmental factors and physiological processes are associated with its etiology, few studies have examined how these factors jointly predict inhibitory control. This study examined whether respiratory sinus arrhythmia (RSA) functioned as a mediator or moderator of both cumulative sociodemographic risk and parenting behaviors on inhibitory control during early childhood. METHODS: The sample included 206 children and their biological mothers. At 24, 30, and 36 months of child age dyads participated in a series of laboratory visits in which sociodemographic, parenting, and baseline RSA (RSAB) data were collected. Inhibitory control was assessed at 36 months using a gift-wrap delay task. RESULTS: A series of structural equation models yielded no evidence that RSAB mediated the relations of risk or parenting and inhibitory control. RSAB moderated the effects of risk, such that high-risk children with low RSAB performed more poorly on tasks of inhibitory control, while high-risk children with high RSAB did not. CONCLUSIONS: These results suggest that higher levels of RSAB may mitigate the influence of environmental risk on the development of inhibitory control early childhood.

Sexual Minority Stress and Same-Sex Relationship Well-Being: A Meta-Analysis of Research Prior to the U.S. Nationwide Legalization of Same-Sex Marriage.

Meta-analytic methods were used to analyze 179 effect sizes retrieved from 32 research reports on the implications that sexual minority stress may have for same-sex relationship well-being. Sexual minority stress (aggregated across different types of stress) was moderately and negatively associated with same-sex relationship well-being (aggregated across different dimensions of relationship well-being). Internalized homophobia was significantly and negatively associated with same-sex relationship well-being, whereas heterosexist discrimination and sexual orientation visibility management were not. Moreover, the effect size for internalized homophobia was significantly larger than those for heterosexist discrimination and sexual orientation visibility management. Sexual minority stress was significantly and negatively associated with same-sex relationship quality but not associated with closeness or stability. Sexual minority stress was significantly and negatively associated with relationship well-being among same-sex female couples but not among same-sex male couples. The current status of research approaches in this field was also summarized and discussed.

Intimate Partner Violence and Children's Attachment Representations during Middle Childhood.

Despite long-standing hypotheses that intimate partner violence (IPV) may undermine children's ability to form secure attachment representations, few studies have empirically investigated this association. Particularly lacking is research that examines IPV and attachment during middle childhood, a time when the way that children understand, represent, and process the behavior of others becomes particularly important. Using data from a sample of African American children living in rural, low-income communities (n = 98), the current study sought to address this gap by examining the association between physical IPV occurring early in children's lives and their attachment security during the first grade. Results indicate that, even after controlling for child- and family-level covariates, physical IPV was associated with a greater likelihood of being rated insecurely attached. This effect was above and beyond the influence of maternal parenting behaviors, demonstrating a unique effect of physical IPV on children's attachment representations during middle childhood.

Individual differences in the activity of the hypothalamic pituitary adrenal axis: Relations to age and cumulative risk in early childhood.

This study examined individual differences in the function of the hypothalamic-pituitary-adrenal (HPA) axis with regard to age and cumulative risk during challenging laboratory tasks administered at 6, 12, 24, and 36 months. Saliva samples were collected from a majority-minority sample of N=185 children (57% African American, 50% female) prior to and following these tasks and later assayed for cortisol. Cumulative distal risk was indexed via a composite of maternal marital status, maternal education, income-to-needs ratio, the number of children in the household, and maternal age at childbirth. Probing of hierarchical models in which cortisol levels and age were nested within child revealed significant differences in cortisol as a function of both age and cumulative risk, such that children exposed to high levels of risk exhibited higher levels of cortisol both within and across age. These results highlight the sensitivity of the HPA axis to environmental context at the level of the individual, even as that sensitivity is manifest against the background of species-typical biological development.

Associations between early caregiving and rural, low-SES, African-American children's representations of attachment relationships.

Little research has examined the legacy of early maternal care for later attachment representations among low-income and ethnic minority school-aged children. Using data from a sample of 276 rural, low-income, African-American families, this study examined associations between maternal care in infancy and children's representations of attachment figures in middle childhood. Maternal care was coded from 10-min home-based observations at 6, 15, and 24 months of age. Representations of attachment figures were assessed using the Manchester Child Attachment Story Task at 6 years of age. Sensitive maternal care in infancy was not significantly related to attachment security or episodic disorganized behaviors in children's representations. However, children exposed to more harsh-intrusive parenting during infancy displayed less secure representations of attachment figures in middle childhood and more episodic disorganized behaviors, even after controlling for numerous child and family contextual covariates. Findings inform conceptualizations of attachment formation among rural, low-income, African-American parent-child dyads.