Hypothalamic-pituitary-adrenal axis reactivity in the preschool-age offspring of depressed parents: moderation by early parenting

The interplay of family history of depression and early trauma: associations with lifetime and current depression in the German national cohort (NAKO)

Introduction

Family history of depression and childhood maltreatment are established risk factors for depression. However, how these factors are interrelated and jointly influence depression risk is not well understood. The present study investigated (i) if childhood maltreatment is associated with a family history of depression (ii) if family history and childhood maltreatment are associated with increased lifetime and current depression, and whether both factors interact beyond their main effects, and (iii) if family history affects lifetime and current depression via childhood maltreatment.

Methods

Analyses were based on a subgroup of the first 100,000 participants of the German National Cohort (NAKO), with complete information (58,703 participants, mean age = 51.2 years, 53% female). Parental family history of depression was assessed via self-report, childhood maltreatment with the Childhood Trauma Screener (CTS), lifetime depression with self-reported physician's diagnosis and the Mini-International Neuropsychiatric Interview (MINI), and current depressive symptoms with the depression scale of the Patient Health Questionnaire (PHQ-9). Generalized linear models were used to test main and interaction effects. Mediation was tested using causal mediation analyses.

Results

Higher frequencies of the childhood maltreatment measures were found in subjects reporting a positive family history of depression. Family history and childhood maltreatment were independently associated with increased depression. No statistical interactions of family history and childhood maltreatment were found for the lifetime depression measures. For current depressive symptoms (PHQ-9 sum score), an interaction was found, with stronger associations of childhood maltreatment and depression in subjects with a positive family history. Childhood maltreatment was estimated to mediate 7%-12% of the effect of family history on depression, with higher mediated proportions in subjects whose parents had a depression onset below 40 years. Abuse showed stronger associations with family history and depression, and higher mediated proportions of family history effects on depression than neglect.

Discussion

The present study confirms the association of childhood maltreatment and family history with depression in a large population-based cohort. While analyses provide little evidence for the joint effects of both risk factors on depression beyond their individual effects, results are consistent with family history affecting depression via childhood maltreatment to a small extent.

Maternal depression and child telomere length: The role of genetic sensitivity

BACKGROUND

The stress of a mother's depression may increasingly tax psychobiological systems that help children with self-regulation, increasing children's allostatic load over time. Some evidence supports children exposed to maternal depression tend to have shorter telomeres and tend to have more somatic and psychological problems. Children having one or more A1 alleles of dopamine receptor 2 (DRD2, rs1800497), tend to have greater sensitivity to maternal depression and could experience more adverse child outcomes that contribute to greater allostatic load.

METHODS

Using the Future Families and Child Wellbeing dataset, secondary-data analyses were used to test the effect of repeated exposure to maternal depression during early childhood on children's telomere length during middle childhood moderated by children's DRD2 genotype (N = 2884).

RESULTS

Greater maternal depression was not significantly associated with shorter child telomere length and this association was not moderated by DRD2 genotypes while controlling for factors associated with child telomere length.

IMPLICATIONS

The effect of maternal depression on children's TL may not be significant in populations from diverse racial-ethnic and family backgrounds during middle childhood. These findings could help further our current understanding psychobiological systems affected by maternal depression that result in adverse child outcomes.

LIMITATIONS

Even though this study used a relatively large and diverse sample, replication of DRD2 moderation in even larger samples is an important next step.

Early childhood stress responses to psychosocial stressors: The state of the science

The aim of this systematic review was to better understand whether and to what extent psychosocial stressors are associated with hypothalamic-pituitary-adrenal axis or autonomic nervous system stress responses in young children (1-6 years of age). Studies were classified by psychosocial stressors from the ecobiodevelopmental model: social and economic resources, maternal mental health, parent-child relationships, and the physical environment. Of the 2388 identified studies, 32 met full inclusion criteria, including over 9107 children. Child physiologic stress responses were measured as hair and urinary cortisol and cortisone, salivary diurnal and reactive cortisol, salivary reactive alpha-amylase, and respiratory sinus arrhythmia. There were 107 identified relations between psychosocial stressors and physiologic stress responses. Nearly two thirds of these relations suggested that children have dysregulated stress responses as either significantly blunted (n = 27) or increased (n = 37); 43 relations were not significant. Children most consistently had significantly dysregulated stress responses if they experienced postnatal maternal depression or anxiety. Some reasons for the mixed findings may be related to characteristics of the child (i.e., moderators) or stressor, how the stress response or psychosocial stressor was measured, unmeasured variables (e.g., caregiving buffering), researcher degrees of freedom, or publication bias.

Basal and reactive cortisol: A systematic literature review of offspring of parents with depressive and bipolar disorders

One of the most consistent biological findings in the study of affective disorders is that those with depression commonly show abnormal cortisol response, which suggests dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. Children of parents with mood disorders offer the opportunity to explore the biological pathways that may confer risk for psychopathology. This review explores basal and reactive cortisol in the offspring of parents who are currently depressed or have had a history of a depressive or bipolar disorder. Using PRISMA guidelines, search terms yielded 2002 manuscripts. After screening, 87 of these manuscripts were included. Results from the literature suggest that while the degree and direction of dysregulation varies, offspring of a parent with depression tend to show elevations in both basal (particularly morning and evening) and reactive (tentatively for social stressors) cortisol levels. There were few studies focused on offspring of parents with bipolar disorder. This review also discusses implications and recommendations for future research regarding the HPA axis in the intergenerational transmission of depressive disorders.

Trajectory of Maternal Postpartum Depressive Symptoms Moderates the Bidirectional Associations between Maternal Intrusive Parenting and Infant Fear

BACKGROUND

The association between maternal intrusive parenting and infant fear remains poorly understood, especially in the persistence of maternal postpartum depression. The current study investigated the moderating role of maternal postpartum depressive symptoms on the bidirectional link between maternal intrusive parenting and infant fear, among a sample of low-income, rural mothers.

METHODS

. A sample of 1,292 mothers reported their depressive symptoms at 2, 6, 15, and 24 months postpartum, whereas their intrusive parenting behavior and infant fear were observed at infants age 6, 15, and 24 months.

RESULTS

. Latent growth curve models revealed that maternal postpartum depressive symptoms increased over 2 years. From 6 months to 24 months, maternal intrusive parenting remained stable, and infant fear increased. Moderation analyses revealed that when mothers had low levels of initial depressive symptoms, a higher initial level of maternal intrusive parenting predicted a faster increase of infant fear. Additionally, when mothers' depressive symptoms showed a fast increase, a higher initial level of infant fear predicted a faster reduction in maternal intrusive parenting.

LIMITATIONS

. The low-income, rural community sample limited the generalizability of the current findings.

CONCLUSIONS

. The interplay between maternal intrusive parenting and infant fear supports a transactional model of child development in the context of maternal depression, with implications for future research and intervention efforts.

Are Preschoolers' Neurobiological Stress Systems Responsive to Culturally Relevant Contexts?

Adults are biologically responsive to context, and their responses to particular situations may differ across cultures. However, are preschoolers' biological systems also responsive to situational contexts and cultures? Here, we show that children's neurobiological stress responses, as indexed by salivary cortisol, are activated and responsive to psychosocial stressors relevant to their sociocultural emphases. By examining cortisol changes across different contexts among 138 preschoolers living in the United States, China, and Japan, we found that an achievement-related stressor elicited an increased cortisol response among Chinese preschoolers, whereas interpersonal-related stressors elicited an increased cortisol response among Japanese preschoolers. By contrast, U.S. preschoolers showed decreased cortisol responses after these stressors but consistently higher levels of anticipatory responses to separation at the beginning of each session. Our findings suggest that children's neurobiological stress systems may be a critical biological mechanism allowing societal-level cultural phenomena to be embodied in individual-level responses, even among preschoolers.

A systematic review of caregiver-child physiological synchrony across systems: Associations with behavior and child functioning

Extensive research has established a positive association between caregiver-child behavioral synchrony and child developmental functioning. Burgeoning research examining physiological synchrony has yet to elucidate its impact for children's developing self-regulation. The objectives of this systematic review were to: 1) determine whether there is evidence that caregiver-child physiological synchrony promotes positive child development, 2) examine developmental differences in physiological synchrony and its correlates, and 3) explore whether context, risk, and/or stress influence patterns of synchrony. Sixty-nine studies met the following criteria on PubMed and PsycINFO: 1) peer-reviewed empirical articles in English that 2) examine autonomic, hypothalamic-pituitary-adrenocortical, and/or central nervous system activity 3) for caregivers and children 4) in response to a task and 5) directly examine the association between caregiver and child physiology. Findings varied based on developmental period and current behavioral context. Functional differences may exist across physiological systems and contexts. Synchrony may have different developmental consequences for dyads with and without certain risk factors. Few studies examine physiological synchrony across multiple systems or contexts, nor do they measure child characteristics associated with synchrony. Statistical and methodological challenges impede interpretation. Findings generally support the idea that physiological synchrony may support children's developing self-regulation. Longitudinal research is needed to examine child developmental outcomes over time.

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.

Maternal depression alters stress and immune biomarkers in mother and child

BACKGROUND

Exposure to maternal depression bears long-term negative consequences for children's well-being. Yet, no study has tested the joint contribution of maternal and child's hypothalamic pituitary axis and immune systems in mediating the effects of maternal depression on child psychopathology.

METHODS

We followed a birth cohort over-represented for maternal depression from birth to 10 years (N = 125). At 10 years, mother and child's cortisol (CT) and secretory immunoglobulin A (s-IgA), biomarkers of the stress and immune systems, were assayed, mother-child interaction observed, mothers and children underwent psychiatric diagnosis, and children's externalizing and internalizing symptoms reported.

RESULTS

Depressed mothers had higher CT and s-IgA levels and displayed more negative parenting, characterized by negative affect, intrusion, and criticism. Children of depressed mothers exhibited more Axis-I disorders, higher s-IgA levels, and greater social withdrawal. Structural equation modeling charted four paths by which maternal depression impacted child externalizing and internalizing symptoms: (a) increasing maternal CT, which linked with higher child CT and behavior problems; (b) augmenting maternal and child's immune response, which were associated with child symptoms; (c) enhancing negative parenting that predicted child social withdrawal and symptoms; and (d), via a combined endocrine-immune pathway suppressing symptom formation.

CONCLUSIONS

Our findings, the first to test stress and immune biomarkers in depressed mothers and their children in relation to social behavior, describe mechanisms of endocrine synchrony in shaping children's stress response and immunity, advocate the need to follow the long-term effects of maternal depression on children's health throughout life, and highlight maternal depression as an important public health concern.

Age-Adapted Stress Task in Preschoolers Does not Lead to Uniform Stress Responses

Acute stress response measures serve as an indicator of physiological functioning, but have previously led to contradictory results in young children due to age-related cortisol hypo-responsivity and methodological inconsistencies in assessment. The aim of this study was to investigate stress responses during a validated age-adapted socio-evaluative stress task in children aged 2-6 years in a child care environment and to detect socio-demographic, task- and child-related characteristics of stress responses. Stress responses were assessed in 323 children for salivary cortisol and salivary alpha amylase (sAA), and in 328 children for changes in heart rate variability (HRV). These data were then associated with socio-demographic (e.g. SES), task-related (e.g. task length) and child-related characteristics (e.g. self-regulation) of stress responses using multilevel models. Analyses revealed elevated sympathetic reactivity (sAA: Coeff=0.053, p=0.004) and reduced HRV (Coeff=-0.465, p<0.001), but no hypothalamic-pituitary-adrenal (HPA) response (Coeff=0.017, p=0.08) during the stress task. Child's age (Coeff=-5.82, p<0.001) and movement during the task (Coeff=-0.17, p=0.015) were associated with acute cortisol release, while diurnal sAA was associated with acute sAA release (Coeff=0.24, p<0.001). Age (Coeff=-0.15, p=0.006) and duration of the task (Coeff=0.13, p=0.015) were further associated with change of HRV under acute stress condition. Children showed inconsistent stress responses which contradicts the assumption of a parallel activation of both stress systems in a valid stress task for young children and might be explained by a pre-arousal to the task of young children in a child care setting. Further results confirm that child- and task-related conditions need to be considered when assessing stress responses in these young children.

Wearable sensors detect childhood internalizing disorders during mood induction task

There is a significant need to develop objective measures for identifying children under the age of 8 who have anxiety and depression. If left untreated, early internalizing symptoms can lead to adolescent and adult internalizing disorders as well as comorbidity which can yield significant health problems later in life including increased risk for suicide. To this end, we propose the use of an instrumented fear induction task for identifying children with internalizing disorders, and demonstrate its efficacy in a sample of 63 children between the ages of 3 and 7. In so doing, we extract objective measures that capture the full six degree-of-freedom movement of a child using data from a belt-worn inertial measurement unit (IMU) and relate them to behavioral fear codes, parent-reported child symptoms and clinician-rated child internalizing diagnoses. We find that IMU motion data, but not behavioral codes, are associated with parent-reported child symptoms and clinician-reported child internalizing diagnosis in this sample. These results demonstrate that IMU motion data are sensitive to behaviors indicative of child psychopathology. Moreover, the proposed IMU-based approach has increased feasibility of collection and processing compared to behavioral codes, and therefore should be explored further in future studies.

Emotion socialization as a predictor of physiological and psychological responses to stress

Reactivity patterns to acute stress are important indicators of physical and mental health. However, the relationships between emotion socialization and stress responses are not well understood. This study aimed to examine whether parental responses to negative emotions predicted physiological and psychological responses to acute stress in late adolescence and emerging adulthood, and whether these relationships varied by gender and ethnicity. Participants were 973 individuals (mean age=19.20years; 50% male; 63% African American, 34% European American) who reported on parental emotion socialization. Participants completed a standardized social stress test (the Trier Social Stress Test; TSST). Heart rate, blood pressure and salivary samples were assessed from baseline throughout the task and during recovery period. Psychological responses to stress were measured immediately after the TSST. Unsupportive parental responses to children's negative emotions were associated with blunted cortisol reactivity and greater negative emotions to a psychosocial stress task in females and African American youth, whereas supportive parental responses predicted greater cortisol reactivity and lower negative emotions to stress in European American youth, as well as less negative emotions in males. However, parental responses to negative emotions did not predict heart rate or SBP reactivity to the TSST. Findings suggest that parental emotion socialization may be an important factor influencing HPA axis reactivity and psychological responses to stress, with important differences across gender and ethnic youth subgroups.

The interaction between parenting and children's cortisol reactivity at age 3 predicts increases in children's internalizing and externalizing symptoms at age 6

Little is known about the role of stress reactivity in the emergence of psychopathology across early childhood. In this longitudinal study, we tested the hypothesis that child cortisol reactivity at age 3 moderates associations between early parenting and children's internalizing and externalizing symptoms from age 3 to age 6. One hundred and sixty children were assessed at age 3, and 135 children were reassessed at age 6. At age 3, we exposed children to stress-inducing laboratory tasks, during which we obtained four salivary cortisol samples, and parental hostility was assessed using an observational parent-child interaction task. At ages 3 and 6, child psychiatric symptoms were assessed using a clinical interview with parents. The results indicated that the combination of high child cortisol reactivity and high observed parental hostility at age 3 was associated with greater concurrent externalizing symptoms at age 3 and predicted increases in internalizing and externalizing symptoms from age 3 to age 6. Findings highlight that increased stress reactivity, within the context of hostile parenting, plays a role in the emergence of psychopathology from preschool to school entry.

Child anxiety symptoms related to longitudinal cortisol trajectories and acute stress responses: evidence of developmental stress sensitization

Cross-sectional research suggests that individuals at risk for internalizing disorders show differential activation levels and/or dynamics of stress-sensitive physiological systems, possibly reflecting a process of stress sensitization. However, there is little longitudinal research to clarify how the development of these systems over time relates to activation during acute stress, and how aspects of such activation map onto internalizing symptoms. We investigated children's (n = 107) diurnal hypothalamic-pituitary-adrenal activity via salivary cortisol (morning and evening levels) across 29 assessments spanning 6+ years, and related longitudinal patterns to acute stress responses at the end of this period (age 9-10). Associations with child psychiatric symptoms at age 10 were also examined to determine internalizing risk profiles. Increasing morning cortisol levels across assessments predicted less of a cortisol decline following interpersonal stress at age 9, and higher cortisol levels during performance stress at age 10. These same profiles of high and/or sustained cortisol elevation during psychosocial stress were associated with child anxiety symptoms. Results suggest developmental sensitization to stress-reflected in rising morning cortisol and eventual hyperactivation during acute stress exposure-may distinguish children at risk for internalizing disorders.

The Swiss Preschoolers' health study (SPLASHY): objectives and design of a prospective multi-site cohort study assessing psychological and physiological health in young children

Background

Children’s psychological and physiological health can be summarized as the child’s thinking, feeling, behaving, eating, growing, and moving. Children’s psychological and physiological health conditions are influenced by today’s life challenges: Thus, stress exposure and lack of physical activity represent important health challenges in older children. However, corresponding evidence for young children is scarce. The aim of Swiss Preschoolers’ Health Study (SPLASHY) is to examine the role of stress and physical activity on children’s psychological and physiological health, particularly on cognitive functioning, psychological well-being, adiposity and motor skills in children at an early stage of childhood. We will also assess the role of child and environmental characteristics and aim to define sensitive time points.

Methods/design

In a total of 84 child care centers, children at preschool age (2–6 years) are recruited and are assessed immediately and one year later. Assessments include direct measurements of the children in the child care centers and at home as well as assessments of children’s behavior and environmental factors through informants (parents and child care educators).

Discussion

SPLASHY is one of the first studies in early childhood aiming to investigate the influence of stress and physical activity on children’s psychological and physiological health in a community-based longitudinal design.

Trial registration

Current Controlled Trials ISRCTN41045021 (date of registration: 21.03.14)

Self-Reported and Observed Punitive Parenting Prospectively Predicts Increased Error-Related Brain Activity in Six-Year-Old Children

The error-related negativity (ERN) is a negative deflection in the event-related potential (ERP) occurring approximately 50 ms after error commission at fronto-central electrode sites and is thought to reflect the activation of a generic error monitoring system. Several studies have reported an increased ERN in clinically anxious children, and suggest that anxious children are more sensitive to error commission--although the mechanisms underlying this association are not clear. We have previously found that punishing errors results in a larger ERN, an effect that persists after punishment ends. It is possible that learning-related experiences that impact sensitivity to errors may lead to an increased ERN. In particular, punitive parenting might sensitize children to errors and increase their ERN. We tested this possibility in the current study by prospectively examining the relationship between parenting style during early childhood and children's ERN approximately 3 years later. Initially, 295 parents and children (approximately 3 years old) participated in a structured observational measure of parenting behavior, and parents completed a self-report measure of parenting style. At a follow-up assessment approximately 3 years later, the ERN was elicited during a Go/No-Go task, and diagnostic interviews were completed with parents to assess child psychopathology. Results suggested that both observational measures of hostile parenting and self-report measures of authoritarian parenting style uniquely predicted a larger ERN in children 3 years later. We previously reported that children in this sample with anxiety disorders were characterized by an increased ERN. A mediation analysis indicated that ERN magnitude mediated the relationship between harsh parenting and child anxiety disorder. Results suggest that parenting may shape children's error processing through environmental conditioning and thereby risk for anxiety, although future work is needed to confirm this hypothesis.

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.

Maternal intimate partner violence exposure, child cortisol reactivity and child asthma

Psychosocial stressors like intimate partner violence (IPV) exposure are associated with increased risk of childhood asthma. Longitudinal studies have not investigated the role of hypothalamic-pituitary-adrenal (HPA) axis reactivity (and associated alterations in cortisol release) in the child IPV exposure-asthma association. We sought to investigate this association, and to assess whether this relationship differs by child HPA reactivity. This secondary analysis used longitudinal cohort data from the Family Life Project. Participants included 1,292 low-income children and mothers; maternal interview and child biomarker data, including maternal report of IPV and child asthma, and child salivary cortisol obtained with validated stress reactivity paradigms, were collected when the child was 7, 15, 24, 35, and 48 months. Using structural equation modeling, maternal IPV when the child was 7 months of age predicted subsequent reports of childhood asthma (B=0.18, p=.002). This association differed according to the child's HPA reactivity status, with IPV exposed children who were HPA reactors at 7 and 15 months of age--defined as a ≥10% increase in cortisol level twenty minutes post peak arousal during the challenge tasks and a raw increase of at least .02μg/dl--being significantly at risk for asthma (7 months: B=0.17, p=.02; 15 months: B=0.17, p=.02). Our findings provide support that children who are physiologically reactive are the most vulnerable to adverse health outcomes when faced with environmental stressors.

Correlates and consequences of toddler cortisol reactivity to fear

Cortisol reactivity to fear-eliciting stimuli during toddlerhood may represent an indicator of risk for anxiety spectrum problems and other maladjustment. Thus, it is important to understand factors that may contribute to cortisol reactivity as well as those that determine its predictive relation to early emerging anxiety. In this vein, the current study investigated maternal comforting behaviors, both solicited and unsolicited by the toddler, as correlates of cortisol reactivity at 2years of age. Furthermore, we investigated maternal comforting behaviors and behavioral indicators of fear in both a low-threat and a high-threat context as moderators of the relation between cortisol reactivity at age 2 and change in anxiety from age 2 to age 3. The sample comprised 99 2-year-old toddlers and their mothers. Toddlers provided saliva samples at baseline and after a fear-eliciting stimulus that were assayed for cortisol. Mothers were observed for comforting behavior while interacting with their toddlers in laboratory tasks and completed questionnaires about their toddlers' anxiety. Results indicated that unsolicited (spontaneous) comforting behavior related to toddler cortisol reactivity above and beyond solicited comforting and the level of fear toddlers displayed in the same task. Moreover, fear in a low-threat context, but not in a high-threat context, moderated the relation between cortisol reactivity and change in anxiety, such that cortisol reactivity had a positive relation to anxiety at extreme levels of low-threat fear. Results suggest the importance of considering the caregiving environment and context-specific fear in understanding the nature of cortisol reactivity during the toddler years.

Parental depression and child cognitive vulnerability predict children's cortisol reactivity

Risk for depression is expressed across multiple levels of analysis. For example, parental depression and cognitive vulnerability are known markers of depression risk, but no study has examined their interactive effects on children's cortisol reactivity, a likely mediator of early depression risk. We examined relations across these different levels of vulnerability using cross-sectional and longitudinal methods in two community samples of children. Children were assessed for cognitive vulnerability using self-reports (Study 1; n = 244) and tasks tapping memory and attentional bias (Study 2; n = 205), and their parents were assessed for depression history using structured clinical interviews. In both samples, children participated in standardized stress tasks and cortisol reactivity was assessed. Cross-sectionally and longitudinally, parental depression history and child cognitive vulnerability interacted to predict children's cortisol reactivity; associations between parent depression and elevated child cortisol activity were found when children also showed elevated depressotypic attributions as well as attentional and memory biases. Findings indicate that models of children's emerging depression risk may benefit from the examination of the interactive effects of multiple sources of vulnerability across levels of analysis.

Influence of maternal depression on children's brooding rumination: Moderation by CRHR1 TAT haplotype

There is growing evidence that brooding rumination plays a key role in the intergenerational transmission of major depressive disorder (MDD) and may be an endophenotype for depression risk. However, less is known about the mechanisms underlying this role. Therefore, the goal of the current study was to examine levels of brooding in children of mothers with a history of MDD (n = 129) compared to children of never depressed mothers (n = 126) and to determine whether the variation in a gene known to influence hypothalamic-pituitary-adrenal axis functioning--corticotropin-releasing hormone receptor 1 (CRHR1)--would moderate the link between maternal MDD and children's levels of brooding. We predicted children of mothers with a history of MDD would exhibit higher levels of brooding than children of mothers with no lifetime depression history but that this link would be stronger among children carrying no copies of the protective CRHR1 TAT haplotype. Our results supported these hypotheses and suggest that the development of brooding among children of depressed mothers, particularly children without the protective CRHR1 haplotype, may serve as an important mechanism of risk for the intergenerational transmission of depression.

Maternal postnatal depression predicts altered offspring biological stress reactivity in adulthood

The offspring of depressed parents have been found to show elevated basal levels of the stress hormone cortisol. Whether heightened cortisol stress reactivity is also present in this group has yet to be clearly demonstrated. We tested whether postnatal maternal depression predicts subsequent increases in offspring biological sensitivity to social stress, as indexed by elevated cortisol reactivity. Participants (mean age 22.4-years) derived from a 22-year prospective longitudinal study of the offspring of mothers who had postnatal depression (PND group; n=38) and a control group (n=38). Salivary cortisol response to a social-evaluative threat (Trier Social Stress Test) was measured. Hierarchical linear modelling indicated that PND group offspring showed greater cortisol reactivity to the stress test than control group participants. Group differences were not explained by offspring depressive or anxiety symptoms, experiences of negative life events, elevated basal cortisol at age 13-years, subsequent exposure to maternal depression, or other key covariates. The findings indicate that the presence of early maternal depression can predict offspring biological sensitivity to social stress in adulthood, with potential implications for broader functioning.

Mothers' early depressive symptoms predict children's low social competence in first grade: mediation by children's social cognition

BACKGROUND

This study examined whether social-cognitive processes in children mediate relations between mothers' depressive symptoms across the first 3 years and children's first-grade social competence. Three maladaptive cognitions were examined: self-perceived social inadequacy, hostile attribution, and aggressive response generation.

METHOD

One thousand three hundred and sixty-four mothers reported depressive symptoms across early development, first-grade children reported target social cognitions, and children's first-grade social competence was observed and reported by multiple informants.

RESULTS

Findings demonstrated that (a) mothers' average depressive symptoms from 6 to 36 months predicted children's maladaptive social cognition in first grade, (b) low mother-child responsiveness mediated this relation, and (c) maladaptive social cognition mediated relations between mothers' early depressive symptoms and low first-grade social competence independent of later depressive symptoms.

CONCLUSION

When mothers' depressive symptoms occur early in development, they may set in motion low-responsive dyadic patterns that promote children's maladaptive social cognition and, as a result, low social competence.

Adolescent adrenocortical activity and adiposity: differences by sex and exposure to early maternal depression

Prior research has linked either basal cortisol levels or stress-induced cortisol responses to adiposity; however, it remains to be determined whether these distinct cortisol measures exert joint or independent effects. Further, it is unclear how they interact with individual and environmental characteristics to predict adiposity. The present study aims to address whether morning cortisol levels and cortisol responses to a psychosocial stressor independently and/or interactively influence body mass index (BMI) in 218 adolescents (117 female) participating in a longitudinal community study, and whether associations are moderated by sex and exposure to early maternal depression. Reports of maternal depressive symptoms were obtained in infancy and preschool. Salivary cortisol measures included a longitudinal morning cortisol measure comprising sampling points across ages 11, 13, 15, and 18 and measures of stress-induced cortisol responses assessed via the Trier Social Stress Test (TSST) at age 18. Lower morning cortisol and higher TSST cortisol reactivity independently predicted higher age 18 BMI. Morning cortisol also interacted with sex and exposure to early maternal depression to predict BMI. Specifically, girls exposed to lower levels of early maternal depression displayed a strong negative morning cortisol-BMI association, and girls exposed to higher levels of maternal depression demonstrated a weaker negative association. Among boys, those exposed to lower levels of maternal depression displayed no association, while those exposed to higher levels of maternal depression displayed a negative morning cortisol-BMI association. Results point to the independent, additive effects of morning and reactive cortisol in the prediction of BMI and suggest that exposure to early maternal depression may exert sexually dimorphic effects on normative cortisol-BMI associations.

Links between white matter microstructure and cortisol reactivity to stress in early childhood: evidence for moderation by parenting

Activity of the hypothalamic–pituitary–adrenal axis (measured via cortisol reactivity) may be a biological marker of risk for depression and anxiety, possibly even early in development. However, the structural neural correlates of early cortisol reactivity are not well known, although these would potentially inform broader models of mechanisms of risk, especially if the early environment further shapes these relationships. Therefore, we examined links between white matter architecture and young girls' cortisol reactivity and whether early caregiving moderated these links. We recruited 45 6-year-old girls based on whether they had previously shown high or low cortisol reactivity to a stress task at age 3. White matter integrity was assessed by calculating fractional anisotropy (FA) of diffusion-weighted magnetic resonance imaging scans. Parenting styles were measured via a standardized parent–child interaction task. Significant associations were found between FA in white matter regions adjacent to the left thalamus, the right anterior cingulate cortex, and the right superior frontal gyrus (all ps < .001). Further, positive early caregiving moderated the effect of high cortisol reactivity on white matter FA (all ps ≤ .05), with high stress reactive girls who received greater parent positive affect showing white matter structure more similar to that of low stress reactive girls. Results show associations between white matter integrity of various limbic regions of the brain and early cortisol reactivity to stress and provide preliminary support for the notion that parenting may moderate associations.

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We examined neural correlates of cortisol reactivity to stress in young girls.

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DTI was performed in young girls to examine white matter fractional anisotropy (FA).

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Lower FA was linked to high cortisol reactivity to stress.

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Differences in neuronal fiber projections were linked to cortisol reactivity.

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Parenting style buffered the effect of high cortisol reactivity on white matter FA.

Exposure to maternal distress in childhood and cortisol activity in young adulthood

Dysregulated cortisol is a risk factor for poor health outcomes. Children of distressed mothers exhibit dysregulated cortisol, yet it is unclear whether maternal distress predicts cortisol activity in later developmental stages. This longitudinal study examined the prospective relation between maternal distress during late childhood (9–12 years) and adolescence (15–19 years) and cortisol response in offspring in young adulthood (24–28 years). Data were collected from 51 recently divorced mothers and their children across 15 years. Higher maternal distress during late childhood was associated with lower total cortisol independent of levels of maternal distress in adolescence or young adulthood. Maternal distress during adolescence marginally predicted blunted cortisol when distress in childhood was low. Findings suggest that blunted cortisol activity in young adulthood may be a long-term consequence of exposure to maternal distress earlier in development.

Maternal parenting predicts infant biobehavioral regulation among women with a history of childhood maltreatment

Early biobehavioral regulation, a major influence of later adaptation, develops through dyadic interactions with caregivers. Thus, identification of maternal characteristics that can ameliorate or exacerbate infants' innate vulnerabilities is key for infant well-being and long-term healthy development. The present study evaluated the influence of maternal parenting, postpartum psychopathology, history of childhood maltreatment, and demographic risk on infant behavioral and physiological (i.e., salivary cortisol) regulation using the still-face paradigm. Our sample included 153 women with high rates of childhood maltreatment experiences. Mother-infant dyads completed a multimethod assessment at 7 months of age. Structural equation modeling showed that maternal positive (i.e., sensitive, warm, engaged, and joyful) and negative (i.e., overcontrolling and hostile) behaviors during interactions were associated with concurrent maternal depressive symptoms, single parent status, and low family income. In turn, positive parenting predicted improved infant behavioral regulation (i.e., positive affect and social behaviors following the stressor) and decreased cortisol reactivity (i.e., posttask levels that were similar to or lower than baseline cortisol). These findings suggest increased risk for those women experiencing high levels of depressive symptoms postpartum and highlight the importance of maternal positive interactive behaviors during the first year for children's neurodevelopment.

Mothers' early depressive symptoms and children's first-grade adjustment: a transactional analysis of child withdrawal as a mediator

BACKGROUND

The depression-inhibition hypothesis suggests that mothers' depressive symptoms undermine development because they lead children to withdraw from social contact. To test this, this study examined whether poor first-grade adjustment among children of mothers with depressive symptoms is mediated by the emergence of child withdrawal in early development.

METHOD

Based on 1,364 dyads, four waves of data spanning from 24 months to first grade (7 years) were used to examine paths by which children's withdrawal mediates relations between mothers' early depressive symptoms and three first-grade outcomes: social competence, academic performance, and externalizing behavior problems.

RESULTS

Structural equation modeling revealed three principal paths. First, direct relations were observed: Mothers' depressive symptoms predicted early child withdrawal and increases in child withdrawal over time, which predicted poor first-grade adjustment. Second, reciprocal relations were observed: Mothers' depressive symptoms predicted child withdrawal, which predicted increases in depressive symptoms. Third, relations via mother-child mutual responsiveness were observed: Depression-related increases in child withdrawal predicted declines in mutual responsiveness, which predicted poor first-grade adjustment.

CONCLUSION

The findings suggest that, due to its interdependence with maternal depression and low mother-child mutual responsiveness over time, child withdrawal may play an important role in the poor first-grade adjustment of children whose mothers are high in depressive symptoms.

Early exposure to parental depression and parenting: associations with young offspring's stress physiology and oppositional behavior

Hypothalamic-pituitary-adrenal (HPA) axis reactivity to stress is posited to play a role in the intergenerational transmission of risk for psychopathology and other negative outcomes in the offspring of depressed parents. We tested the hypothesis that the joint, interactive effects of exposure to parental depression during early childhood and parental hostility impact the development of young children's stress physiology and early emerging behavior problems. A sample of 165 preschool-age children (81 boys, 84 girls), of whom 103 had a parent with a history of depression, was exposed to a stress-inducing laboratory task, and five salivary cortisol samples were obtained. Parents completed clinical interviews and an observational parent-child interaction task. We found that the offspring exposed to maternal depression during early childhood and whose parents displayed hostile parenting behaviors during an observational task evidenced high and increasing cortisol levels in response to a laboratory stressor. In addition, the total amount of exposure to maternal depression over the child's life exerted a dose-response effect on the positive relation between parental hostility and child observed oppositional behavior. This study underscores the importance of the early rearing environment on young children's stress physiology and early emerging behavior problems.

Blunted stress cortisol reactivity and failure to acclimate to familiar stress in depressed and sub-syndromal children

Depressed adults have shown blunted or elevated cortisol reactivity in response to various forms of psychosocial stress. However, there have been few studies of cortisol reactivity in children who had early onset depression or a history of depression during the preschool-school period. The present study utilized a laboratory stress paradigm and collected salivary cortisol from preschoolers at baseline (ages 3-5 years) and 24-month follow-up (ages 5-7 years). Repeated-measures multivariate analyses of variance (MANOVAs) were used to compare cortisol reactivity to mild stress between children with Major Depressive Disorder (MDD), elevated symptoms of depression (sub-syndromal MDD), and healthy controls. For healthy children, a quadratic cortisol reactivity curve was found at baseline (n=73), which appeared flatter under similar stressful situations at follow-up (n=14), which may reflect acclimation to the paradigm. In contrast, children with MDD (n=46) and sub-syndromal MDD (n=76) showed a peak cortisol response to the novelty of lab arrival and then reduced and blunted responses to stressors at baseline. These cortisol responses persisted at follow-up in children with a history of MDD (n=41) or sub-syndromal MDD (n=73). These results suggest that the hypothalamic-pituitary-adrenal (HPA) axis shows a blunted response to stress and failed to acclimate to familiar stressful situations in depressed and sub-syndromal depressed children.

Mothers' depressive symptoms and infant negative emotionality in the prediction of child adjustment at age 3: Testing the maternal reactivity and child vulnerability hypotheses

This study examined individual differences in how mothers' depressive symptoms affect children's early adjustment. It tested whether problematic development among children high in negative emotionality is accentuated by (a) maternal reactivity, the negative reactivity of mothers with depressive symptoms to difficult child characteristics; and (b) child vulnerability, the susceptibility of negatively emotional children to the negative parenting of mothers with depressive symptoms. Based on 1,364 participants from the NICHD Study of Early Child Care, results showed that mothers' depressive symptoms predicted greater risk for adjustment problems at age 3 among children who as infants were high rather than low in negative emotionality. Increased risk was evident for behavior problems, low responsiveness, high separation distress, and low social competence. Mediational tests suggested that increased risk reflected maternal reactivity: the stronger mothers' depressive symptoms, the more they responded with negative parenting to children high in negative emotionality. The proposal that child vulnerability mediates the greater impact of mothers' depressive symptoms on negatively emotional children was verified only for separation distress. The results support the proposal that, when mothers are high in depressive symptoms, aversive characteristics of children and their behavior increasingly influence early adjustment and do so because they elicit negative parent behavior.

Effortful control and parenting: associations with HPA axis reactivity in early childhood

While activation of the hypothalamic-pituitary-adrenal (HPA) axis is an adaptive response to stress, excessive HPA axis reactivity may be an important marker of childhood vulnerability to psychopathology. Parenting, including parent affect during parent-child interactions, may play an important role in shaping the developing HPA system; however, the association of parent affect may be moderated by child factors, especially children's emerging self-regulatory skills. We therefore tested the relationship between parent affectivity and 160 preschoolers' cortisol reactivity during a laboratory visit, examining children's effortful control (EC) as a moderator. Greater parent negative affectivity was related to greater initial and increasing cortisol over time, but only when children were low in EC. Higher parent positive affectivity was related to a higher baseline cortisol for children with low EC and lower baseline cortisol for children with high EC. Results indicate that children's EC moderates the extent to which parent affect shapes stress reactive systems in early childhood.

Pathways and processes of risk in associations among maternal antisocial personality symptoms, interparental aggression, and preschooler's psychopathology

Two studies examined the nature and processes underlying the joint role of interparental aggression and maternal antisocial personality as predictors of children's disruptive behavior problems. Participants for both studies included a high-risk sample of 201 mothers and their 2-year-old children in a longitudinal, multimethod design. Addressing the form of the interplay between interparental aggression and maternal antisocial personality as risk factors for concurrent and prospective levels of child disruptive problems, the Study 1 findings indicated that maternal antisocial personality was a predictor of the initial levels of preschooler's disruptive problems independent of the effects of interparental violence, comorbid forms of maternal psychopathology, and socioeconomic factors. In attesting to the salience of interparental aggression in the lives of young children, latent difference score analyses further revealed that interparental aggression mediated the link between maternal antisocial personality and subsequent changes in child disruptive problems over a 1-year period. To identify the family mechanisms that account for the two forms of intergenerational transmission of disruptive problems identified in Study 1, Study 2 explored the role of children's difficult temperament, emotional reactivity to interparental conflict, adrenocortical reactivity in a challenging parent-child task, and experiences with maternal parenting as mediating processes. Analyses identified child emotional reactivity to conflict and maternal unresponsiveness as mediators in pathways between interparental aggression and preschooler's disruptive problems. The findings further supported the role of blunted adrenocortical reactivity as an allostatic mediator of the associations between parental unresponsiveness and child disruptive problems.

Effects of prenatal and postnatal parent depressive symptoms on adopted child HPA regulation: independent and moderated influences

This study used a prospective adoption design to investigate effects of prenatal and postnatal parent depressive symptom exposure on child hypothalamic-pituitary-adrenal (HPA) activity and associated internalizing symptoms. Birth mother prenatal symptoms and adoptive mother/father postnatal (9-month, 27-month) symptoms were assessed with the Beck Depression Inventory in a sample of 192 families as part of the Early Growth and Development adoption Study. Child morning/evening cortisol levels and child symptoms of internalizing disorders (according to mother/father report on the Child Behavior Checklist) were assessed at 54 months, and birth mother diurnal cortisol was measured at 48 months postnatal. Hierarchical linear modeling was used to test main effects and interactions of parents' symptoms predicting child cortisol, controlling for birth mother cortisol. Prenatal exposure to birth mother symptoms predicted lower child cortisol (main effect), as did postnatal exposure to adoptive parent symptoms (interaction effects). Adoptive mother 9-month symptoms exacerbated cortisol-lowering effects of both concurrent paternal symptoms and later (27-month) maternal symptoms, and the effect of birth mother cortisol. Lower child cortisol, in turn, was associated with higher child internalizing symptoms. Implications are discussed with respect to the intergenerational transmission of depression risk.

Racial and ethnic differences in diurnal cortisol rhythms in preadolescents: the role of parental psychosocial risk and monitoring

Racial/ethnic minorities experience persistent health disparities due in part to their exposure to chronic SES and psychosocial risk. The hypothalamic-pituitary-adrenal axis and its hormonal end product, cortisol, are believed to mediate the associations between chronic stress and poor health. In this study, racial/ethnic differences in diurnal salivary cortisol rhythms in 179 preadolescent youths and the contributing roles of SES risk, psychosocial risk, perceived discrimination, harsh parenting, and parental monitoring were examined. The analyses revealed racial/ethnic differences in diurnal cortisol rhythms, with African Americans having significantly flatter morning-to-evening cortisol slopes than Caucasians and with Latinos having significantly lower evening cortisol levels than Caucasians. Greater psychosocial risk and less parental monitoring were associated with flatter cortisol slopes. Racial/ethnic differences on the cortisol measures persisted when controlling for SES, psychosocial risk, and parenting quality. The need to assess chronic risk across the lifespan and disentangle possible genetic from environmental contributors is discussed.

Infants' behavioral and physiological profile and mother–infant interaction

This study aims to (a) identify and profile groups of infants according to their behavioral and physiological characteristics, considering their neurobehavioral organization, social withdrawal behavior, and endocrine reactivity to stress, and to (b) analyze group differences in the quality of mother–infant interaction. Ninety-seven 8-week-old infants were examined using the Neonatal Behavioral Assessment Scale and the Alarm Distress Baby Scale. Cortisol levels were measured both before and after routine inoculation between 8 and 12 weeks. At 12 to 16 weeks mother–infant interaction was assessed using the Global Rating Scales of Mother–Infant Interaction. Three groups of infants were identified: (a) “withdrawn”; (b) “extroverted”; (c) “underaroused.” Differences between them were found regarding both infant and mother behaviors in the interaction and the overall quality of mother–infant interaction. The identification of behavioral and physiological profiles in infants is an important step in the study of developmental pathways.