Psychological stress in childhood and susceptibility to the chronic diseases of aging: moving toward a model of behavioral and biological mechanisms

Childhood adversity and DNA methylation of genes involved in the hypothalamus-pituitary-adrenal axis and immune system: whole-genome and candidate-gene associations

In recent years, translational research involving humans and animals has uncovered biological and physiological pathways that explain associations between early adverse circumstances and long-term mental and physical health outcomes. In this article, we summarize the human and animal literature demonstrating that epigenetic alterations in key biological systems, the hypothalamus-pituitary-adrenal axis and immune system, may underlie such disparities. We review evidence suggesting that changes in DNA methylation profiles of the genome may be responsible for the alterations in hypothalamus-pituitary-adrenal axis and immune system trajectories. Using some preliminary data, we demonstrate how explorations of genome-wide and candidate-gene DNA methylation profiles may inform hypotheses and guide future research efforts in these areas. We conclude our article by discussing the many important future directions, merging perspectives from developmental psychology, molecular genetics, neuroendocrinology, and immunology, that are essential for furthering our understanding of how early adverse circumstances may shape developmental trajectories, particularly in the areas of stress reactivity and physical or mental health.

Potential epigenetic mechanism(s) associated with the persistence of psychoneurological symptoms in women receiving chemotherapy for breast cancer: a hypothesis

Due to recent treatment advances, there have been improvements in the proportion of women surviving a diagnosis of breast cancer (BC). However, many of these survivors report persistent adverse side effects following treatment, such as cognitive dysfunction, depressive symptoms, anxiety, fatigue, sleep disturbances, and pain. Investigators have examined circulating levels of inflammatory markers, particularly serum cytokines, for a potential causal relationship to the development/persistence of these psychoneurological symptoms (PNS). While inflammatory activation, resulting from perceived stress or other factors, may directly contribute to the development of PNS, we offer an alternative hypothesis, suggesting that these symptoms are an early step in a cascade of biological changes leading to epigenetic alterations at the level of deoxyribonucleic acid (DNA) methylation, histone modifications, and/or chromatin structure/chromosomal instability. Given that epigenetic patterns have plasticity, if this conjectured relationship between epigenomic/acquired genomic alterations and the development/persistence of PNS is confirmed, it could provide foundational knowledge for future research leading to the recognition of predictive markers and/or treatments to alleviate PNS in women with BC. In this article, we discuss an evolving theory of the biological basis of PNS, integrating knowledge related to inflammation and DNA repair in the context of genetic and epigenetic science to expand the paradigm for understanding symptom acquisition/persistence following chemotherapy.

Annual Research Review: Resilient functioning in maltreated children--past, present, and future perspectives

BACKGROUND

Through a process of probabilistic epigenesis, child maltreatment progressively contributes to compromised adaptation on a variety of developmental domains central to successful adjustment. These developmental failures pose significant risk for the emergence of psychopathology across the life course. In addition to the psychological consequences of maltreatment, a growing body of research has documented the deleterious effects of abuse and neglect on biological processes. Nonetheless, not all maltreated children develop maladaptively. Indeed, some percentage of maltreated children develops in a resilient fashion despite the significant adversity and stress they experience.

METHODS

The literature on the determinants of resilience in maltreated children is selectively reviewed and criteria for the inclusion of the studies are delineated.

RESULTS

The majority of the research on the contributors to resilient functioning has focused on a single level of analysis and on psychosocial processes. Multilevel investigations have begun to appear, resulting in several studies on the processes to resilient functioning that integrate biological/genetic and psychological domains.

CONCLUSIONS

Much additional research on the determinants of resilient functioning must be completed before we possess adequate knowledge based on a multiple levels of analysis approach that is commensurate with the complexity inherent in this dynamic developmental process. Suggestions for future research on the development of resilient functioning in maltreated children are proffered and intervention implications are discussed.

Predicting adult physical illness from infant attachment: a prospective longitudinal study

OBJECTIVE

Recent epidemiological and longitudinal studies indicate that attachment relationships may be a significant predictor of physical health in adulthood. This study is among the few to prospectively link attachment classifications assessed in infancy to physical health outcomes 30 years later in adulthood, controlling for various health-related confounds.

METHODS

Participants were 163 individuals involved in a 32-year longitudinal study of risk and adaptation who have been followed since birth. Attachment classifications were assessed at ages 12 and 18 months using the Ainsworth Strange Situation Procedure. Stability of attachment security was derived from these assessments. At age 32, participants completed a questionnaire asking about the presence of or treatment for current physical illnesses.

RESULTS

Binary logistic regression analyses controlling for health-related confounds at age 32 indicated that individuals who were insecurely attached (i.e., anxious-resistant or anxious-avoidant) during infancy were more likely to report an inflammation-based illness in adulthood than those classified as securely attached during infancy. There also was a trend whereby individuals classified as anxious-resistant reported more nonspecific symptoms in adulthood than those classified as either anxious-avoidant or secure. Individuals who were continuously insecure during infancy were more likely to report all types of physical illness in adulthood.

CONCLUSION

These findings reveal the lasting effect of early interpersonal relationships on physical health and suggests that infancy may be a fruitful point for prevention efforts. The widespread influence that attachment has on endogenous and exogenous health-related processes may make it particularly potent in the prevention of later physical health problems.

The long-term impact of early adversity on late-life psychiatric disorders

Early adversity is a strong and enduring predictor of psychiatric disorders including mood disorders, anxiety disorders, substance abuse or dependence, and posttraumatic stress disorder. However, the mechanisms of this effect are not well understood. The purpose of this review is to summarize and integrate the current research knowledge pertaining to the long-term effects of early adversity on psychiatric disorders, particularly in late life. We explore definitional considerations including key dimensions of the experience such as type, severity, and timing of adversity relative to development. We then review the potential biological and environmental mediators and moderators of the relationships between early adversity and psychiatric disorders. We conclude with clinical implications, methodological challenges and suggestions for future research.

Ethnic Disparities in Disability Among Middle-Aged and Older Israeli Adults

Objectives: We examined the contribution of socioeconomic disadvantage and traumatic life events to ethnic disparities in disability among Israeli adults. Method: We used data from the Survey of Health, Aging and Retirement in Europe (SHARE-Israel), a sample of Israeli adults aged 50 or older ( N = 1,546). Disability measures included functional limitations, limitations in activities of daily living (ADL), and limitations in instrumental activities of daily living (IADL). Results: Arabs and immigrants from the Former Soviet Union (FSU) experienced higher rates of functional limitations and limitations in IADLs compared to veteran Jews. The rate of having limitations in ADLs was similar for Arabs and veteran Jews, but was higher for FSU immigrants compared to veteran Jews. Inclusion of education, income, and traumatic life events attenuated, but did not eliminate ethnic disparities in disability. Discussion: Identifying factors driving ethnic health disparities in Israel is imperative if we hope to achieve health equity.

Stigma as a fundamental cause of population health inequalities

Bodies of research pertaining to specific stigmatized statuses have typically developed in separate domains and have focused on single outcomes at 1 level of analysis, thereby obscuring the full significance of stigma as a fundamental driver of population health. Here we provide illustrative evidence on the health consequences of stigma and present a conceptual framework describing the psychological and structural pathways through which stigma influences health. Because of its pervasiveness, its disruption of multiple life domains (e.g., resources, social relationships, and coping behaviors), and its corrosive impact on the health of populations, stigma should be considered alongside the other major organizing concepts for research on social determinants of population health.

The Emerging Field of Human Social Genomics

Although we generally experience our bodies as being biologically stable across time and situations, an emerging field of research is demonstrating that external social conditions, especially our subjective perceptions of those conditions, can influence our most basic internal biological processes-namely, the expression of our genes. This research on human social genomics has begun to identify the types of genes that are subject to social-environmental regulation, the neural and molecular mechanisms that mediate the effects of social processes on gene expression, and the genetic polymorphisms that moderate individual differences in genomic sensitivity to social context. The molecular models resulting from this research provide new opportunities for understanding how social and genetic factors interact to shape complex behavioral phenotypes and susceptibility to disease. This research also sheds new light on the evolution of the human genome and challenges the fundamental belief that our molecular makeup is relatively stable and impermeable to social-environmental influence.

Household income is associated with the p53 mutation frequency in human breast tumors

BACKGROUND

A study from Scotland reported that the p53 mutation frequency in breast tumors is associated with socio-economic deprivation.

METHODS

We analyzed the association of the tumor p53 mutational status with tumor characteristics, education, and self-reported annual household income (HI) among 173 breast cancer patients from the greater Baltimore area, United States.

RESULTS

p53 mutational frequency was significantly associated with HI. Patients with < $15,000 HI had the highest p53 mutation frequency (21%), followed by the income group between $15,000 and $60,000 (18%), while those above $60,000 HI had the fewest mutations (5%). When dichotomized at $60,000, 26 out of 135 patients in the low income category had acquired a p53 mutation, while only 2 out of 38 with a high income carried a mutation (P < 0.05). In the adjusted logistic regression analysis with 3 income categories (trend test), the association between HI and p53 mutational status was independent of tumor characteristics, age, race/ethnicity, tobacco smoking and body mass. Further analyses revealed that HI may impact the p53 mutational frequency preferentially in patients who develop an estrogen receptor (ER)-negative disease. Within this group, 42% of the low income patients (< $15,000 HI) carried a mutation, followed by the middle income group (21%), while those above $60,000 HI did not carry mutations (Ptrend < 0.05).

CONCLUSIONS

HI is associated with the p53 mutational frequency in patients who develop an ER-negative disease. Furthermore, high income patients may acquire fewer p53 mutations than other patients, suggesting that lifetime exposures associated with socio-economic status may impact breast cancer biology.

Cortisol response to social stress in parentally bereaved youth

BACKGROUND

Parental bereavement is associated with increased risk for psychiatric illness and functional impairment in youth. Dysregulated hypothalamic-pituitary-adrenal (HPA) axis functioning may be one pathway through which bereaved children experience increased risk for poor outcomes. However, few studies have prospectively examined the association between parental bereavement and cortisol response while accounting for psychiatric disorders in both youth and their caregivers.

METHODS

One-hundred and eighty-one bereaved and nonbereaved offspring and their caregivers were assessed at multiple time points over a 5-year period after parental death. Offspring participated in an adaptation of the Trier Social Stress Task (TSST), and salivary cortisol samples were collected before and after exposure to social stressors. Mixed models for repeated measures were used to analyze the effects of bereavement status, psychiatric disorder in both offspring and caregiver, and demographic indices on trajectories of cortisol response.

RESULTS

After controlling for demographic variables and offspring depression, bereaved offspring demonstrated significantly different trajectories of cortisol response compared with nonbereaved offspring, characterized by higher total cortisol output and an absence of cortisol reactivity to acute social stress. Within the bereaved group, offspring of parents who died by sudden natural death demonstrated significant cortisol reactivity to social stress compared with offspring whose parents died by suicide, who demonstrated more blunted trajectory of cortisol response.

CONCLUSIONS

Parentally bereaved youth demonstrate higher cortisol output than nonbereaved youth but are less able to mount an acute response in the face of social stressors.

Childhood abuse and inflammatory responses to daily stressors

BACKGROUND

Childhood abuse leads to greater morbidity and mortality in adulthood. Dysregulated physiological stress responses may underlie the greater health risk among abused individuals.

PURPOSE

This study evaluated the impact of childhood abuse on inflammatory responses to naturalistically occurring daily stressors.

METHODS

In this cross-sectional study of 130 older adults, recent daily stressors and childhood abuse history were evaluated using the Daily Inventory of Stressful Events and the Childhood Trauma Questionnaire. Blood samples provided data on circulating interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and C-reactive protein (CRP).

RESULTS

Childhood abuse history moderated IL-6 levels but not TNF-α and CRP responses to daily stressors. Individuals with a childhood abuse history who experienced multiple stressors in the past 24 h had IL-6 levels 2.35 times greater than those of participants who reported multiple daily stressors but no early abuse history.

CONCLUSION

Childhood abuse substantially enhances IL-6 responses to daily stressors in adulthood.

Dysregulated diurnal cortisol pattern is associated with glucocorticoid resistance in women with major depressive disorder

Dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis is believed to play a role in the pathophysiology of depression. To investigate mechanisms that may underlie this effect, we examined several indices of HPA axis function - specifically, diurnal cortisol slope, cortisol awakening response, and suppression of cortisol release following dexamethasone administration - in 26 pre-menopausal depressed women and 23 never depressed women who were matched for age and body mass index. Salivary cortisol samples were collected at waking, 30 min after waking, and at bedtime over three consecutive days. On the third day, immediately after the bedtime sample, participants ingested a 0.5mg dexamethasone tablet; they then collected cortisol samples at waking and 30 min after waking the following morning. As predicted, depressed women exhibited flatter diurnal cortisol rhythms and more impaired suppression of cortisol following dexamethasone administration than non-depressed women over the three sampling days. In addition, flatter diurnal cortisol slopes were associated with reduced cortisol response to dexamethasone treatment, both for all women and for depressed women when considered separately. Finally, greater self-reported depression severity was associated with flatter diurnal cortisol slopes and with less dexamethasone-related cortisol suppression for depressed women. Depression in women thus appears to be characterized by altered HPA axis functioning, as indexed by flatter diurnal cortisol slopes and an associated impaired sensitivity of cortisol to dexamethasone. Given that altered HPA axis functioning has been implicated in several somatic conditions, the present findings may be relevant for understanding the pathophysiology of both depression and depression-related physical disease.

Childhood adversity and cell-mediated immunity in young adulthood: does type and timing matter?

Childhood adversity can have powerful effects on health over the life course. Persistent changes in cell-mediated immune function may be one pathway linking adverse childhood experiences with later disease risk. However, limited research has examined childhood adversity in relation to cell-mediated immune function, and in particular, immune response to latent viruses in adulthood. The present study investigated the association of two types of childhood adversity, socioeconomic disadvantage during adolescence and abuse prior to age 18, with Epstein-Barr Virus (EBV) antibody titers in a large nationally representative sample of young adults aged 24-32years. Data were drawn from the National Longitudinal Study on Adolescent Health, Wave 4 (n=13,162). We examined the associations of three indicators of adolescent SES (parental education, household income, and occupational status) and frequency and timing of physical and sexual abuse with EBV antibodies, controlling for age, sex, race/ethnicity, and presence of a smoker in the household during adolescence. Lower parental occupational status and some categories of lower education were associated with elevated EBV antibodies (p<.05), and individuals who reported sexual abuse that occurred more than 10times had elevated EBV antibodies relative to individuals who were not sexually abused (p=0.03). Among individuals exposed to physical abuse, those who were first abused at age 3-5years had heightened EBV antibodies relative to those first abused during adolescence (p=0.004). This study extends prior research linking early adversity and immune function, and provides initial evidence that childhood adversity has a persistent influence on immune responses to latent infection in adulthood.

Increased frequency of micronuclei in adults with a history of childhood sexual abuse: a discordant monozygotic twin study

BACKGROUND

Childhood sexual abuse (CSA) is a traumatic life event associated with an increased lifetime risk for psychopathology/morbidity. The long-term biological consequences of CSA-elicited stress on chromosomal stability in adults are unknown. The primary aim of this study was to determine if the rate of acquired chromosomal changes, measured using the cytokinesis-block micronucleus assay on stimulated peripheral blood lymphocytes, differs in adult female monozygotic twins discordant for CSA.

METHODS

Monozygotic twin pairs discordant for CSA were identified from a larger population-based sample of female adult twins for whom the experience of CSA was assessed by self-report (51 individuals including a reference sample). Micronuclei (MN) contain chromatin from structurally normal or abnormal chromosomes that are excluded from the daughter nuclei during cell division and serve as a biomarker to assess acquired chromosomal instability.

RESULTS

Female twins exposed to CSA exhibited a 1.63-fold average increase in their frequency of MN compared to their nonexposed genetically identical cotwins (Paired t-test, t₁₆ = 2.65, P = 0.017). No additional effects of familial factors were detected after controlling for the effect of CSA exposure. A significant interaction between CSA history and age was observed, suggesting that the biological effects of CSA on MN formation may be cumulative.

CONCLUSIONS

These data support a direct link between CSA exposure and MN formation measured in adults that is not attributable to genetic or environmental factors shared by siblings. Further research is warranted to understand the biological basis for the observed increase in acquired chromosomal findings in people exposed to CSA and to determine if acquired somatic chromosomal abnormalities/somatic clonal mosaicism might mediate the adult pathology associated with CSA.

The Biological Residue of Childhood Poverty

Children raised in poverty are prone to physical health problems late in life. To understand these findings and address the scientific challenge they represent, we must formulate integrative conceptual frameworks at the crossroads of behavioral and biomedical science, with a strong developmental emphasis. In this article, we outline such a framework and discuss research bearing on its validity. We address how childhood poverty gets under the skin, at the level of tissues and organs, in a manner that affects later disease risks. We also tackle questions about resilience; Even with lengthy exposure to childhood poverty, why do only a subset of people acquire diseases? Why are some individuals protected while others remain vulnerable? Maternal nurturance might be a source of resilience, buffering children from the long-term health consequences of poverty. We conclude with research priorities.

Routine versus catastrophic influences on the developing child

Exposure to toxic stress accelerates the wear and tear on children's developing bodies and leaves a lasting mark on adult health. Prior research has focused mainly on children exposed to extreme forms of adversity, such as maltreatment and extreme neglect. However, repeated exposure to less severe, but often chronic stressors is likely to play as large, if not larger, of a role in forecasting children's future mental and physical health. New tools from neuroscience, biology, epigenetics, and the social sciences are helping to isolate when and how the foundations for adult health are shaped by childhood experiences. We are now in the position to understand how adversity, in both extreme and more mundane forms, contributes to the adult health burden and to identify features in children's families and environments that can be strengthened to buffer the effects of toxic stressors. We are also positioned to develop and implement innovative approaches to child policy and practice that are rooted in an understanding of how exposure to toxic stressors can become biologically embedded. The stage is set for the creation of new interventions--on both grand and micro scales--to reduce previously intractable health disparities.

The evolutionary significance of depression in Pathogen Host Defense (PATHOS-D)

Given the manifold ways that depression impairs Darwinian fitness, the persistence in the human genome of risk alleles for the disorder remains a much debated mystery. Evolutionary theories that view depressive symptoms as adaptive fail to provide parsimonious explanations for why even mild depressive symptoms impair fitness-relevant social functioning, whereas theories that suggest that depression is maladaptive fail to account for the high prevalence of depression risk alleles in human populations. These limitations warrant novel explanations for the origin and persistence of depression risk alleles. Accordingly, studies on risk alleles for depression were identified using PubMed and Ovid MEDLINE to examine data supporting the hypothesis that risk alleles for depression originated and have been retained in the human genome because these alleles promote pathogen host defense, which includes an integrated suite of immunological and behavioral responses to infection. Depression risk alleles identified by both candidate gene and genome-wide association study (GWAS) methodologies were found to be regularly associated with immune responses to infection that were likely to enhance survival in the ancestral environment. Moreover, data support the role of specific depressive symptoms in pathogen host defense including hyperthermia, reduced bodily iron stores, conservation/withdrawal behavior, hypervigilance and anorexia. By shifting the adaptive context of depression risk alleles from relations with conspecifics to relations with the microbial world, the Pathogen Host Defense (PATHOS-D) hypothesis provides a novel explanation for how depression can be nonadaptive in the social realm, whereas its risk alleles are nonetheless represented at prevalence rates that bespeak an adaptive function.

Stressful early life experiences and immune dysregulation across the lifespan

There is considerable evidence that stressful early life events influence a variety of physical health problems later in life. Childhood adversity has been linked to elevated rates of morbidity and mortality from a number of chronic diseases. Immune dysregulation may be one potential pathway that explains this link. In this mini-review, we summarize human studies demonstrating that severe early life stressors have lasting immune consequences. We propose a model outlining potential biobehavioral pathways that explain how early life stressors leave people vulnerable to these maladaptive outcomes. Finally, we suggest ideas for future work to test different aspects of this model.

Divorce and Death: A Case Study for Health Psychology

Marital separation and divorce are associated with increased risk for early death, and the magnitude of this association rivals that of many well-established public health factors. In the case of divorce, however, the mechanisms explaining precisely why and how some people are at risk for early death remain unclear. This paper reviews what is known about the association between divorce and risk for all-cause mortality, then discusses four emerging themes in this area of research: the biological intermediaries linking divorce to pathophysiology and disease onset, moving beyond the statistical mean, focusing research on the diathesis-stress model, and studying how opportunity foreclosures may place people on a trajectory toward poor distal health outcomes. These ideas are grounded in a set of public lay commentaries about the association between divorce and death; in this way, the paper seeks to integrate current research ideas with how the general public thinks about divorce and its correlates. Although this paper focuses on divorce, many of the emerging themes are applicable to the study of psychosocial stress and health more generally. Therefore, the study of divorce and death provides a good case study for health psychology and considers new questions that can be pursued in a variety of research areas.

Early life stress and telomere length: investigating the connection and possible mechanisms: a critical survey of the evidence base, research methodology and basic biology

How can adverse experiences in early life, such as maltreatment, exert such powerful negative effects on health decades later? The answer may lie in changes to DNA. New research suggests that exposure to stress can accelerate the erosion of DNA segments called telomeres. Shorter telomere length correlates with chronological age and also disease morbidity and mortality. Thus, telomere erosion is a potential mechanism linking childhood stress to health problems later in life. However, an array of mechanistic, methodological, and basic biological questions must be addressed in order to translate telomere discoveries into clinical applications for monitoring health and predicting disease risk. This paper covers the current state of the science and lays out new research directions.

Fatigue, brain, behavior, and immunity: summary of the 2012 Named Series on fatigue

The focus on fatigue for the 2012 Named Series in brain, behavior, and immunity reflects the growing wave of research examining immune underpinnings of fatigue in healthy and clinical populations. Fatigue is prevalent in the general population and in patients with a variety of medical conditions. However, the etiology of fatigue remains elusive. Psychoneuroimmunological approaches to fatigue have yielded important advances in our understanding of this complex symptom and are represented in the twelve articles included in the Named Series. These articles include animal and human models of fatigue and cross a variety of different medical conditions, including cancer, chronic fatigue syndrome, and diabetes. This review briefly summarizes the articles included in the series and highlights the themes that have emerged from this body of work.

How Do Interactions Between Early Caregiving Environment and Genes Influence Health and Behavior?

To promote optimal health and behavioral outcomes in children, nurses have long supported parents in providing the best possible care and nurturance to their offspring. A growing body of neuroscience research argues convincingly for the combined influences of genes and early caregiving on producing an individual's unique health and behavioral phenotype. In this article, we systematically review studies that demonstrate the relationship between qualities of early caregiving and genetic propensity to health and behavioral outcomes. From an initial set of 255 articles, 24 articles met our inclusion criteria. The outcomes fall into four distinct groups: hypothalamic-pituitary-adrenal (HPA) response to stress, externalizing behavior, internalizing behavior, and disorganized attachment. In the articles, authors examined genes that code for the 5-hydroxy tryptamine (serotonin) transporter genes linked polymorphic region [5- HTTLPR] serotonin transporter promoter, D4 dopamine receptor, brain-derived neurotrophic factor, and monoamine oxidase A promoter. The reviewed studies suggest that the effect of the early rearing environment on gene expression relates mainly to HPA response to stress, whereas interactions between genes and caregiving mainly relate to behavior and attachment. Findings have implications for nurses focused on advocacy, prevention, and intervention to support the healthy development of children in families faced with adversity.

Leveraging the biology of adversity to address the roots of disparities in health and development

Extensive evidence that personal experiences and environmental exposures are embedded biologically (for better or for worse) and the cumulative knowledge of more than four decades of intervention research provide a promising opportunity to mobilize evolving scientific insights to catalyze a new era of more effective early childhood policy and practice. Drawing on emerging hypotheses about causal mechanisms that link early adversity with lifelong impairments in learning, behavior, and health, this paper proposes an enhanced theory of change to promote better outcomes for vulnerable, young children by strengthening caregiver and community capacities to reduce or mitigate the impacts of toxic stress, rather than simply providing developmental enrichment for the children and parenting education for their mothers.

Resilience and measured gene–environment interactions

The past decade has witnessed an exponential growth in studies that have attempted to identify the genetic polymporphisms that moderate the influence of environmental risks on mental disorders. What tends to be neglected in these Gene × Environment (G × E) interaction studies has been a focus on resilience, which refers to a dynamic pattern of positive adaptation despite the experience of a significant trauma or adversity. In this article, we argue that one step toward advancing the field of developmental psychopathology would be for G × E research to consider resilience instead of focusing almost exclusively on mental disorders. After providing an up-to-date summary on the expanding definitions and models of resilience, and the available evidence regarding measured G × E studies of childhood maltreatment, we discuss why resilience would be a worthwhile phenotype for studies of measured G × E. First, although G × E hypotheses require that there be an environmental risk (e-risk) involved in a causal process that leads to psychopathology, e-risks are typically not included in the diagnostic criteria for most psychiatric disorders. In contrast, resilience by definition includes an e-risk. Second, G × E hypotheses require that there is evidence of variability in response to an environmental stressor, and resilience often represents the positive end on this continuum of adaptation. Third, both resilience and G × E are best understood from a developmental perspective. Fourth, although resilient outcomes are not public health concerns, the types of adversities (e.g., childhood maltreatment, poverty, or exposure to natural disasters) that are often investigated in studies of resilience certainly are. Understanding how some individuals, perhaps because of their genetic makeup, are able to withstand such adversities can inform prevention and intervention efforts to improve mental health.

Neighborhood disadvantage and adolescent stress reactivity

Lower socioeconomic status (SES) is associated with higher levels of life stress, which in turn affect stress physiology. SES is related to basal cortisol and diurnal change, but it is not clear if SES is associated with cortisol reactivity to stress. To address this question, we examined the relationship between two indices of SES, parental education and concentrated neighborhood disadvantage, and the cortisol reactivity of African–American adolescents to a modified version of the Trier Social Stress Test (TSST). We found that concentrated disadvantage was associated with cortisol reactivity and this relationship was moderated by gender, such that higher concentrated disadvantage predicted higher cortisol reactivity and steeper recovery in boys but not in girls. Parental education, alone or as moderated by gender, did not predict reactivity or recovery, while neither education nor concentrated disadvantage predicted estimates of baseline cortisol. This finding is consistent with animal literature showing differential vulnerability, by gender, to the effects of adverse early experience on stress regulation and the differential effects of neighborhood disadvantage in adolescent males and females. This suggests that the mechanisms underlying SES differences in brain development and particularly reactivity to environmental stressors may vary across genders.

The Psychoneuroimmunology of Stress in Pregnancy

The rate of preterm birth in the United States remains high. In up to 40% of cases of preterm birth, the mothers are healthy women who have no clear risk factors. Accordingly, research has begun to explore the effect of prenatal stress on the risk of preterm birth and shortened gestational age at birth. There is increasing evidence that psychosocial stress throughout gestation increases the risk of preterm birth through changes in maternal endocrine, immune, and inflammatory activity during pregnancy. In this article, I describe foundational and current research examining the effects and biological mechanisms of prenatal stress in preterm birth and shortened gestational age at birth. I emphasize psychoneuroimmunology-focused studies showing that prenatal stress alters inflammatory and endocrine markers during gestation and that these changes are associated with preterm birth and shortened gestational age at birth.

Beating and insulting children as a risk for adult cancer, cardiac disease and asthma

The use of physical punishment for children is associated with poor psychological and behavioral outcomes, but the causal pathway is controversial, and the effects on later physical health unknown. We conducted a cross-sectional survey of asthma, cancer, and cardiac patients (150 in each category, 75 male) recruited from outpatient clinics and 250 healthy controls (125 male). All participants were 40-60 years old and citizens of Saudi Arabia, where the use of beating and insults is an acceptable parenting style. Demographic data and recalled frequency of beatings and insults as a child were assessed on an 8-point scale. Beating and insults were highly correlated (ρ = 0.846). Propensity score matching was used to control for demographic differences between the disease and healthy groups. After controlling for differences, more frequent beating (once or more per month) and insults were associated with a significantly increased risk for cancer (RR = 1.7), cardiac disease (RR = 1.3) and asthma (RR = 1.6), with evidence of increased risk for cancer and asthma with beating frequency of once every 6 months or more. Our results show that a threatening parenting style of beating and insults is associated with increased risk for somatic disease, possibly because this form of parenting induces stress. Our findings are consistent with previous research showing that child abuse and other early life stressors adversely affect adult somatic health, but provide evidence that the pathogenic effects occur also with chronic minor stress. A stress-inducing parenting style, even when normative, has long term adverse health consequences.

Social processes and disease in nonhuman primates: introduction to the special section

Most nonhuman primate species are remarkably social, but their social nature presents many challenges, including increased opportunities for pathogen transmission and development of disease (both physical and psychological). An interdisciplinary symposium was convened at the 2010 annual meeting of the American Society of Primatologists on the topic of social processes and disease in nonhuman primates, and four articles from that session, as well as a fifth that was separately solicited, appear in this special section. The articles reflect a variety of disciplines and perspectives that highlight the many ways that social processes can impact disease processes (and vice versa) in this highly social taxon. This is an increasingly active area of research interest as a consequence of technological developments and the availability of long-term field data. The continuing loss of primate habitat in the wild, climate change, and the need to manage high densities of primates in captivity, however, all add urgency to our need to better understand the bidirectional relationship between social factors and disease processes.

Do depressive traits and hostility predict age-related decline in general intelligence?

Certain personality traits are likely to be associated with stress and distress through the lifespan, and as a consequence these traits may influence the rate of age-related cognitive decline. The present study uses data from the Glostrup 1914 cohort to analyze potential effects of personality on decline in general intelligence over a 30-year period. The Minnesota Multiphasic Personality Inventory was administered at a 50-year baseline exam, and from this inventory the Obvious Depression Scale and an abbreviated version of the Cook-Medley Hostility Scale were derived. At the 50-year baseline and at the 60-, 70-, and 80-year followups the full version of Wechsler's Adult Intelligence Scale (WAIS) was administered to 673, 513, 136, and 184 participants. Mixed effects statistical models were used to evaluate both the effect of the personality scores on level of intelligence and the interaction between the personality scores and the time since followup. Analyses were adjusted for demographic background and a wide range of lifestyle factors. Both obvious depression and hostility were negatively associated with level of intelligence, but personality scores did not influence rate of decline in general intelligence.

Socioeconomic status and the health of youth: a multilevel, multidomain approach to conceptualizing pathways

Previous research has clearly established associations between low socioeconomic status (SES) and poor youth physical health outcomes. This article provides an overview of the main pathways through which low SES environments come to influence youth health. We focus on 2 prevalent chronic health problems in youth today, asthma and obesity. We review and propose a model that encompasses (a) multiple levels of influence, including the neighborhood, family and person level; (b) both social and physical domains in the environment; and finally (c) dynamic relationships between these factors. A synthesis of existing research and our proposed model draw attention to the notion of adverse physical and social exposures in youth's neighborhood environments altering family characteristics and youth psychosocial and behavioral profiles, thereby increasing youth's risk for health problems. We also note the importance of acknowledging reciprocal influences across levels and domains (e.g., between family and child) that create self-perpetuating patterns of influence that further accentuate the impact of these factors on youth health. Finally, we document that factors across levels can interact (e.g., environmental pollution levels with child stress) to create unique, synergistic effects on youth health. Our model stresses the importance of evaluating influences on youth's physical health not in isolation but in the context of the broader social and physical environments in which youth live. Understanding the complex relationships between the factors that link low SES to youth's long-term health trajectories is necessary for the creation and implementation of successful interventions and policies to ultimately reduce health disparities.

Inflammatory pathways link socioeconomic inequalities to white matter architecture

Socioeconomic disadvantage confers risk for aspects of ill health that may be mediated by systemic inflammatory influences on the integrity of distributed brain networks. Following this hypothesis, we tested whether socioeconomic disadvantage related to the structural integrity of white matter tracts connecting brain regions of distributed networks, and whether such a relationship would be mediated by anthropometric, behavioral, and molecular risk factors associated with systemic inflammation. Otherwise healthy adults (N= 155, aged 30-50 years, 78 men) completed protocols assessing multilevel indicators of socioeconomic position (SEP), anthropometric and behavioral measures of adiposity and cigarette smoking, circulating levels of C-reactive protein (CRP), and white matter integrity by diffusion tensor imaging. Mediation modeling was used to test associations between SEP indicators and measures of white matter tract integrity, as well as indirect mediating paths. Measures of tract integrity followed a socioeconomic gradient: individuals completing more schooling, earning higher incomes, and residing in advantaged neighborhoods exhibited increases in white matter fractional anisotropy and decreases in radial diffusivity, relative to disadvantaged individuals. Moreover, analysis of indirect paths showed that adiposity, cigarette smoking, and CRP partially mediated these effects. Socioeconomic inequalities may relate to diverse health disparities via inflammatory pathways impacting the structural integrity of brain networks.

Childhood adversity and herpesvirus latency in breast cancer survivors

OBJECTIVE

Childhood adversity has been linked to greater emotional and physiological sensitivity to stress. Stress has well-documented effects on cellular immunity, including enhanced herpesvirus reactivation. This study assessed whether childhood adversity was associated with the expression of two latent herpesviruses, Epstein-Barr virus (EBV) and cytomegalovirus (CMV) in adults, and whether this association could be detected beyond the psychological distress women experienced in the aftermath of a breast cancer diagnosis and its treatment.

METHODS

One hundred and eight breast cancer survivors completed questionnaires and provided blood samples to assess EBV virus capsid antigen (VCA) IgG antibody titers and CMV IgG antibody titers.

RESULTS

Breast cancer survivors who experienced more childhood adversities had higher EBV and CMV antibody titers than those with fewer childhood adversities. Those who experienced more childhood adversities also had more depressive symptoms, less education, and poorer sleep quality than those with fewer childhood adversities. Depressive symptoms, education, sleep quality, age, BMI, cancer stage, comorbidities, and weekly alcohol consumption were not related to EBV or CMV antibody titers. Time since last treatment was negatively associated with EBV and CMV antibody titers. Elevated antibody titers to latent herpesviruses represent poorer cellular immune system control over viral latency; these data suggest that those with more childhood adversities have poorer cellular immune function.

CONCLUSIONS

These findings add to the emerging literature suggesting that adverse early experiences may make people more vulnerable to immune dysregulation in adulthood. The consequences of early adversity appear to persist across the life span.

Clustering of depression and inflammation in adolescents previously exposed to childhood adversity

BACKGROUND

There is mounting interest in the hypothesis that inflammation contributes to the pathogenesis of depression and underlies depressed patients' vulnerability to comorbid medical conditions. However, research on depression and inflammation has yielded conflicting findings, fostering speculation that these conditions associate only in certain subgroups, such as patients exposed to childhood adversity.

METHODS

We studied 147 female adolescents. All were in good health at baseline but at high risk for depression because of family history or cognitive vulnerability. Subjects were assessed every 6 months for 2.5 years, undergoing diagnostic interviews and venipuncture for measurement of two inflammatory biomarkers, C-reactive protein (CRP) and interleukin-6 (IL-6). Childhood adversity was indexed by parental separation, low socioeconomic status, and familial psychopathology.

RESULTS

Multilevel models indicated that childhood adversity promotes clustering of depression and inflammation. Among subjects exposed to high childhood adversity, the transition to depression was accompanied by increases in both CRP and IL-6. Higher CRP remained evident 6 months later, even after depressive symptoms had abated. These lingering effects were bidirectional, such that among subjects with childhood adversity, high IL-6 forecasted depression 6 months later, even after concurrent inflammation was considered. This coupling of depression and inflammation was not apparent in subjects without childhood adversity.

CONCLUSIONS

These findings suggest that childhood adversity promotes the formation of a neuroimmune pipeline in which inflammatory signaling between the brain and periphery is amplified. Once established, this pipeline leads to a coupling of depression and inflammation, which may contribute to later affective difficulties and biomedical complications.

Gene × Environment interaction and resilience: effects of child maltreatment and serotonin, corticotropin releasing hormone, dopamine, and oxytocin genes

In this investigation, gene-environment interaction effects in predicting resilience in adaptive functioning among maltreated and nonmaltreated low-income children (N = 595) were examined. A multicomponent index of resilient functioning was derived and levels of resilient functioning were identified. Variants in four genes (serotonin transporter linked polymorphic region, corticotropin releasing hormone receptor 1, dopamine receptor D4-521C/T, and oxytocin receptor) were investigated. In a series of analyses of covariance, child maltreatment demonstrated a strong negative main effect on children's resilient functioning, whereas no main effects for any of the genotypes of the respective genes were found. However, gene-environment interactions involving genotypes of each of the respective genes and maltreatment status were obtained. For each respective gene, among children with a specific genotype, the relative advantage in resilient functioning of nonmaltreated compared to maltreated children was stronger than was the case for nonmaltreated and maltreated children with other genotypes of the respective gene. Across the four genes, a composite of the genotypes that more strongly differentiated resilient functioning between nonmaltreated and maltreated children provided further evidence of genetic variations influencing resilient functioning in nonmaltreated children, whereas genetic variation had a negligible effect on promoting resilience among maltreated children. Additional effects were observed for children based on the number of subtypes of maltreatment children experienced, as well as for abuse and neglect subgroups. Finally, maltreated and nonmaltreated children with high levels of resilience differed in their average number of differentiating genotypes. These results suggest that differential resilient outcomes are based on the interaction between genes and developmental experiences.

"Shift-and-Persist" Strategies: Why Low Socioeconomic Status Isn't Always Bad for Health

Some individuals, despite facing recurrent, severe adversities in life such as low socioeconomic status (SES), are nonetheless able to maintain good physical health. This article explores why these individuals deviate from the expected association of low SES and poor health and outlines a "shift-and-persist" model to explain the psychobiological mechanisms involved. This model proposes that, in the midst of adversity, some children find role models who teach them to trust others, better regulate their emotions, and focus on their futures. Over a lifetime, these low-SES children develop an approach to life that prioritizes shifting oneself (accepting stress for what it is and adapting the self through reappraisals) in combination with persisting (enduring life with strength by holding on to meaning and optimism). This combination of shift-and-persist strategies mitigates sympathetic-nervous-system and hypothalamic-pituitary-adrenocortical responses to the barrage of stressors that low-SES individuals confront. This tendency vectors individuals off the trajectory to chronic disease by forestalling pathogenic sequelae of stress reactivity, like insulin resistance, high blood pressure, and systemic inflammation. We outline evidence for the model and argue that efforts to identify resilience-promoting processes are important in this economic climate, given limited resources for improving the financial circumstances of disadvantaged individuals.

Conscientiousness and stress exposure and reactivity: a prospective study of adolescent females

Conscientiousness is associated with health, but the mechanisms remain poorly understood. To explore the role that stress might play, this study examined whether conscientiousness was associated with exposure and reactivity to life stress. This study followed 133 adolescent women every 6 months for 2.5 years. Participants completed a baseline measure of conscientiousness, and at each visit underwent a structured interview to catalogue episodic and chronic stress and had blood drawn to assess inflammatory processes. Participants higher in conscientiousness experienced fewer self-dependent episodic stressors and less academic and interpersonal chronic stress throughout the study. However, at times when they experienced higher levels of chronic interpersonal stress, they became more resistant to glucocorticoids. Higher levels of conscientiousness may protect adolescent women from exposure to certain stressors. However, when stress occurs, highly conscientious individuals may become more resistant to glucocorticoids, increasing their risk for processes that influence inflammatory conditions.

Protective factors for adults from low-childhood socioeconomic circumstances: the benefits of shift-and-persist for allostatic load

OBJECTIVE

Low socioeconomic status (SES) early in life is one of the most well-established social predictors of poor health. However, little is understood about why some adults who grew up in low-SES environments do not have poor health outcomes. This study examined whether the psychological characteristic of "shift-and-persist" protects adults from the physiological risks of growing up in low-SES households. Shift-and-persist consists of reframing appraisals of current stressors more positively (shifting), while simultaneously persisting with a focus on the future. We hypothesized that this characteristic would be associated with reduced physiological risk in low-childhood SES individuals.

METHODS

A national sample of 1207 adults (aged 25-74 years) from the Survey of Midlife Development in the United States completed psychological questionnaires and were queried about parent education. Biologic assessments consisted of 24 different measures across seven physiological systems, from which a composite measure representing cumulative physiological risk (allostatic load) was derived.

RESULTS

Among adults who grew up in low-SES households, those who engaged in high-shift-and-high-persist strategies had the lowest allostatic load (b = -0.15, p = .04). No benefit of shift-and-persist was found for those from higher-childhood SES backgrounds (p = .36).

CONCLUSIONS

Identifying the health-related protective qualities that naturally occur in some low-SES individuals represents one important approach for developing future health improvement interventions for those who start out life low in SES. Moreover, the psychological qualities that are protective from future disease risk for those from low-SES backgrounds are different from those beneficial to high-SES individuals.

Preschoolers' everyday conflict at home and diurnal cortisol patterns

OBJECTIVE

Early life family conflict is associated with physical health problems later in life, but little is known about the biological pathways through which conflict at home exerts it deleterious effects on health. The goal of this study was to investigate the associations between naturalistically assessed conflict in everyday family environments and diurnal cortisol in preschool-aged children.

DESIGN

Forty-four children aged 3-5 from two-parent families provided six saliva samples per day over 2 days from a Saturday morning through Sunday night. For a full day on either Saturday or Sunday, children wore a child version of the Electronically Activated Recorder, a digital voice recorder that records ambient sounds while participants go about their daily lives. Parents provided reports of child externalizing behaviors as well as daily reports of child conflicts.

MAIN OUTCOME MEASURES

Diurnal salivary cortisol over the two weekend days of the study.

RESULTS

Greater Electronically Activated Recorder-assessed child conflict at home was associated with children having lower cortisol at wakeup (p < .009) and flatter diurnal cortisol slopes (p < .007). These associations remained significant even after controlling for parent reports of child externalizing behaviors, parent reports of daily child conflicts, and child age and sex.

CONCLUSION

These findings indicate that taking into consideration everyday conflicts at home may be key to our understanding of stress-health links in young children.