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

Racism and hypothalamic-pituitary-adrenal axis functioning in childhood as risks for health disparities across the lifespan

Racism is a primary social determinant of health and chronic stressor that affects the physical and mental health of People of Color and Indigenous Individuals (POCI) and perpetuates racial and ethnic health disparities. Despite the impact of racism on POCI, the mechanisms through which experiences of racism result in negative health outcomes remain understudied, in particular among children. Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is one of the possible mechanisms. Frequent and prolonged exposure to chronic stressors may result in dysregulation of the HPA axis, and in turn cause adverse physical and psychological health outcomes for POCI children. This paper argues for the importance of examining HPA axis dysregulation as a mechanism that links racism during early childhood to negative health outcomes over the lifespan. Several studies have explored the relationship between racism and HPA axis dysregulation during adulthood and adolescence and have found associations between racism and salivary and hair cortisol. Recent studies have identified racial and ethnic differences in cortisol levels during early childhood, but only one study, to our knowledge, explored whether the differences are attributed to racism. In this paper, we conduct a review of the existing literature on the links between racism and HPA axis dysregulation during adulthood and adolescence given the dearth of studies exploring this relationship during early childhood. We also highlight the importance of utilizing an intersectionality framework in the study of racism and health to provide a more comprehensive and nuanced understanding of health disparities among and within racial/ethnic groups. Using this evidence along with consideration of relevant models, we propose how HPA axis dysregulation identified early in life may foreshadow children's increased risk for negative health outcomes from racism and other systems of oppression and signal the need for prevention and intervention.

Child Temperamental Negative Affectivity Moderates the Relation between Interparental Conflict and Child Cortisol Recovery

This study examined the relation between interparental conflict and cortisol recovery, with child temperamental negative affectivity as the moderator. Children (n = 118) ages 9 to 11 years observed an argument between their parents in the lab and provided saliva samples for cortisol assays. Children also reported levels of interparental conflict, and mothers reported their child's negative affectivity. Results showed that youths with high levels of negative affectivity experienced less cortisol recovery as interparental conflict levels increased. Further, demonstrating some support for differential susceptibility, youths with higher levels of negative affectivity exhibited less recovery at high levels of parental conflict but greater recovery at low levels of parental conflict, compared to peers with lower scores on negative affectivity. We also found that children with low levels of negative affectivity exhibited greater recovery as rates of interparental conflict increased. In summary, this study sheds light on sources of variability in cortisol recovery as it relates to interparental disharmony.

Stress and diurnal cortisol among Latino/a college students: A multi-risk model approach

The transition to college is a time of increased opportunity and stress spanning multiple domains. Adolescents who encounter significant stress during this transition may be vulnerable to adverse outcomes due to a "wear and tear" of the hypothalamic pituitary adrenal (HPA) axis. Latino/a students may be particularly at-risk for heightened stress exposure due to experiences of both minority-specific and general life stress. Despite this, little is known regarding the cumulative impact of multiple stressors on Latino/a students' HPA axis functioning. The present study employed a "multi-risk model" approach to examine additive, common, and cumulative effects of multiple stress forms (general, academic, social, financial, bicultural, ethnic/racial discrimination) on diurnal cortisol in a sample of first-year Latino/a college students (N = 196; 64.4% female; Mage = 18.95). Results indicated that no stress forms were additively associated with the cortisol awakening response (CAR), but general stress was associated with a flatter diurnal cortisol slope (DCS) and bicultural stress was linked with a steeper DCS. A college stress latent factor was associated with a lower CAR, whereas a latent factor of discrimination was not associated with diurnal cortisol. Cumulative risk was linked with a lower CAR. Findings highlight the physiological correlates of various stressors experienced by Latino/a college students.

The Development of Stress Reactivity and Regulation in Children and Adolescents

Adversity experienced in early life can have detrimental effects on physical and mental health. One pathway in which these effects occur is through the hypothalamic-pituitary-adrenal (HPA) axis, a key physiological stress-mediating system. In this review, we discuss the theoretical perspectives that guide stress reactivity and regulation research, the anatomy and physiology of the axis, developmental changes in the axis and its regulation, brain systems regulating stress, the role of genetic and epigenetics variation in axis development, sensitive periods in stress system calibration, the social regulation of stress (i.e., social buffering), and emerging research areas in the study of stress physiology and development. Understanding the development of stress reactivity and regulation is crucial for uncovering how early adverse experiences influence mental and physical health.

Short-term cortisol adaption to discrimination and Mexican-origin adolescents' mental and sleep health

Discrimination experiences are a salient contributor to the health disparities facing Latina/x/o youth. The biopsychosocial model of minority health posits that discrimination influences health through wear and tear on the biological stress responses, including the hypothalamic-pituitary-adrenal (HPA) axis, which is a primary stress response system in the body. Emerging evidence suggests that discrimination alters the secretion of cortisol, the end product of the HPA axis, yet, whether the daily processes between discrimination and diurnal cortisol response influence mental and sleep health remains unanswered. This study integrated daily diary and post-diary survey data to examine whether daily diurnal cortisol responses to discrimination influence adolescents' mental (depressive symptoms, anxiety) and sleep (sleep quality, duration) health in a sample of Mexican-origin youth (N = 282; M age = 17.10; 55% female). Results showed that adolescents who experienced more discrimination across the four-day diary period exhibited steeper diurnal cortisol slopes and lower evening cortisol; however, such physiological responses tended to be associated with poorer adolescents' mental and sleep health. The current study underscores the potential adaptation cost associated with short-term cortisol adaptation in the face of discrimination.

Race, cortisol, and subclinical cardiovascular disease in 9- to 11-year-old children

BACKGROUND

Non-Hispanic Black Americans have a greater risk for certain subtypes of cardiovascular disease (CVD; e.g., stroke and heart failure) relative to non-Hispanic White Americans. Moreover, Black relative to White adults consistently show elevated cortisol, a CVD risk. The impact of race, environmental stress, and cortisol on subclinical CVD has yet to be fully researched in children.

METHOD

We assessed diurnal salivary cortisol slopes and hair cortisol in a sample of 9- to 11-year-old children (N = 271; 54% female) with roughly half self-identifying as either Black (57%) or White (43%). Two subclinical CVD indicators were assessed: carotid-femoral pulse wave velocity (cfPWV) and carotid intima-media thickness (cIMT). We assessed numerous environmental stress indicators.

RESULTS

After adjusting for covariates, we found that Black children had significantly flatter diurnal cortisol slopes, higher hair cortisol, and thicker IMT than White children. Significant pathways were found: race → salivary cortisol slope → cfPWV (effect = -0.059, 95% CI [-0.116, -0.002]) and race → hair cortisol → cIMT (effect = -0.008, [-0.016, -0.002]). Black children also experienced significantly more environmental stress than White children; however, only income inequality served as a significant indirect pathway from race to salivary cortisol (effect = 0.029, [0.003, 0.060]).

CONCLUSIONS

Relative to White children, Black children had significantly greater hair cortisol and flatter diurnal slopes which, in turn, were associated with greater subclinical CVD. As suggested by a significant indirect pathway, income inequality might partially explain the race-cortisol association. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Everyday perceptions of safety and racial disparities in hair cortisol concentration

OBJECTIVE

Black-White disparities in physiological stress during adolescence are increasingly evident but remain incompletely understood. We examine the role of real-time perceptions of safety in the context of everyday routines to gain insight into the sources of observed adolescent racial differences in chronic stress as measured by hair cortisol concentration (HCC).

METHOD

We combined social survey, ecological momentary assessment (EMA), and hair cortisol data on 690 Black and White youth ages 11-17 from wave 1 of the Adolescent Health and Development in Context (AHDC) study to investigate racial differences in physiological stress. Individual-level, reliability-adjusted measures of perceived unsafety outside the home were drawn from a week-long smartphone-based EMA and tested for association with hair cortisol concentration.

RESULTS

We observed a statistically significant interaction (p < .05) between race and perceptions of unsafety. For Black youth, perceived unsafety was associated with higher HCC (p < .05). We observed no evidence of an association between perceptions of safety and expected HCC for White youth. For youth who perceive their out-of-home activity locations to be consistently safe, the racial difference in expected HCC was not statistically significant. At the high end of perceived unsafety, however, Black-White differences in HCC were pronounced (0.75 standard deviations at the 95th percentile on perceived unsafety; p < .001).

DISCUSSION

These findings call attention to the role of everyday perceptions of safety across non-home routine activity contexts in explaining race differences in chronic stress as assessed by hair cortisol concentrations. Future research may benefit from data on in situ experiences to capture disparities in psychological and physiological stress.

Lifetime discrimination, habitual and daily everyday discrimination, and diurnal cortisol among older African Americans adults

Experiences of discrimination can be major life events or daily chronic hassles that occur in various social contexts (e.g., housing, education, employment) and have been found to predict adverse health outcomes, including dysregulation of the Hypothalamic-Pituitary-Adrenal (HPA) axis. Previous work on daily cortisol dynamics has generally revealed an association between discrimination and flatter cortisol slopes, particularly among racial minorities. However, most of the existing studies have focused on youth and young adults, with little work among older adults. The current study aimed to investigate the relationship between three measures of discrimination (lifetime discrimination, habitual everyday discrimination, and daily everyday discrimination) and diurnal cortisol secretion in a sample of 203 older African Americans. Study results indicated that individuals reporting higher levels of lifetime discrimination experienced morning hypocortisolism and flatter diurnal cortisol slopes. Exploratory analyses also showed that prior daily everyday discrimination was significantly associated with blunted cortisol awakening response (CAR) the next day. Our findings underline the role of discrimination in modulating daily cortisol dynamics among older African American adults and advance knowledge on how social stressors influence healthy aging.

Prenatal substance exposure, early-life adversity, and parenting: Associations with adolescent stress response

We tested a conceptual model examining associations between prenatal substance exposure and adolescent cortisol reactivity profiles in response to an acute social evaluative stressor. We included cortisol reactivity in infancy, and direct and interactive effects of early-life adversity and parenting behaviors (sensitivity, harshness) from infancy to early school age on adolescent cortisol reactivity profiles in model testing. Participants were 216 families (51% female children; 116 cocaine-exposed) recruited at birth, oversampled for prenatal substance exposure, and assessed from infancy to early adolescence (EA). Majority of participants self-identified as Black (72% mothers, 57.2% adolescents), and caregivers were primarily from low-income families (76%), were single (86%), and had high school or below education (70%) at recruitment. Latent profile analyses identified three cortisol reactivity patterns including elevated (20.4%), moderate (63.1%), and blunted (16.5%) reactivity groups. Prenatal tobacco exposure was associated with higher likelihood of membership in the elevated reactivity compared to the moderate reactivity group. Higher caregiver sensitivity in early life was associated with lower likelihood of membership in the elevated reactivity group. Prenatal cocaine exposure was associated with higher maternal harshness. Interaction effects among early-life adversity and parenting indicated that caregiver sensitivity buffered, and harshness exacerbated, the likelihood that high early adversity would be associated with the elevated and blunted reactivity groups. Results highlight the potential importance of prenatal alcohol and tobacco exposure for cortisol reactivity and the role of parenting as exacerbating or buffering the impact of early-life adversity on adolescent stress response.

Maternal stress and mental health before pregnancy and offspring diurnal cortisol in early childhood

The current study investigates whether prepregnancy maternal posttraumatic stress disorder (PTSD) symptoms, depressive symptoms, and stress predict children's cortisol diurnal slopes and cortisol awakening responses (CARs) adjusting for relevant variables. Mothers were enrolled after delivering a baby and followed through their subsequent pregnancy with 5 years of longitudinal data on their subsequent child. This prospective design allowed assessment of PTSD symptoms, depressive symptoms, and perceived stress prior to pregnancy. Children provided three saliva samples per day on three consecutive days at two timepoints in early childhood (M age = 3.7 years, SD = 0.38; M age = 5.04 years, SD = 0.43). Mothers' PTSD symptoms prior to pregnancy were significantly associated with flatter child diurnal cortisol slopes at 4 and 5 years, but not with child CAR. Findings at the age of 4 years, but not 5 years, remained statistically significant after adjustment for maternal socioeconomic status, race/ethnicity, child age, and other covariates. In contrast, maternal prepregnancy depressive symptoms and perceived stress did not significantly predict cortisol slopes or CAR. Results suggest that maternal prepregnancy PTSD symptoms may contribute to variation in early childhood physiology. This study extends earlier work demonstrating risk of adverse outcomes among children whose mothers experienced trauma but associations cannot be disentangled from effects of prenatal mental health of mothers on children's early childhood.

Race/ethnicity and age associations with hair cortisol concentrations among children studied longitudinally from early through middle childhood

A total of 513 children were included in this secondary analysis of data from the NET-Works trial of low income children at risk for obesity. The purpose of the analysis was to examine HCC longitudinally over 5 assessments from early through middle childhood with the goal of i) determining if there were racial/ethnic differences in HCC, and if so, how early in childhood these differences could be observed; and (ii) whether racial/ethnic differences in HCC reflected structural and family-level indicators of disadvantage. The sample consisted of children from diverse racial/ethnic backgrounds: Black, including Hispanic Black (N = 156), non-Hispanic White (N = 67) and Non-Black Hispanic (N = 290) children. As the largest group, the last group was used as the reference group in analyses. Structural and family-level indicators of disadvantage, including the neighborhood child opportunity index (COI), family income, and parent perceived neighborhood safety, were collected at each assessment. The results showed higher HCC among Black children beginning as early as 2-4 years of age than non-Black Hispanic children who did not differ from non-Hispanic White children. Although family income and COI were lower for children from minoritized racial-ethnic backgrounds, entering these measures as covariates did not reduce the difference in HCC between Black children and the other two groups. The results also showed that HCC initially decreased with age and then plateaued, with no evidence that this pattern differed by race/ethnicity. Because of the potential health risks of chronically elevated cortisol concentrations, these data argue for increased attention to the myriad of factors (oppressive structures, systems, and interpersonal experiences) that likely contribute to elevated cortisol levels among Black children.

Parenting and Adjustment Problems among Preschoolers during COVID-19

A critical area of developmental science explores factors that confer risk or protection as young children and their families experience stressful circumstances related to sociohistorical events. This study contributes to this important area by assessing relations between family context and child adjustment as children transitioned from preschool to home learning during COVID-19, and whether children higher in stress levels, indexed by morning basal cortisol, were more strongly affected. Parents of 74 children (M _age  = 53.56 months, SD _age = 3.68 months) completed reports spanning the home learning transition; children's pre-COVID-19 transition salivary cortisol levels were assessed. Path analyses were used to test the preregistered study aims. Significant interactions were decomposed using simple slopes and Preacher's Regions of Significance (ROS) method. Across the COVID-19 transition to home-based school, children with higher morning basal cortisol experienced the sharpest increase in anger when exposed to harsh/inconsistent parenting contexts. Importantly, these effects held when controlling for household chaos, socioeconomic resources, and supportive parenting. Parallel models with supportive parenting were also tested and are discussed. This study is one of the first to test and provide support for biological sensitivity to context theory within the context of a natural experiment like COVID-19.

Cortisol in early childhood moderates the association between family routines and observed affective balance in children from low-income backgrounds

The study of emotion regulation often addresses control of negative emotion. Researchers have proposed that affective balance is an indicator of emotion regulation that incorporates the role of positive emotion in the context of negative emotional experiences. Environmental and individual factors, such as family processes and biological stress regulation, are known to shape emotion regulation. The present study investigated whether child diurnal cortisol, an indicator of biological stress regulation, moderated the association between family routines and observed affective balance. Children (N = 222; M age = 4.70 years, SD = 0.60) from low-income households provided saliva samples to measure diurnal cortisol and completed a behavioral task designed to elicit negative emotions. Affective balance was defined as the difference score between the proportion of positive and negative emotional expressions displayed during the task. A higher affective balance score indicated greater positive compared with negative emotional displays. Simple slope analyses indicated that for children with a low morning cortisol intercept, more frequent family routines were associated with more affective balance. This pattern was not observed in children with average or high morning cortisol. Positive family routines may play an important role in shaping affective balance among children with disrupted cortisol levels from low-income backgrounds.

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

BACKGROUND

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

METHODS

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

RESULTS

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

DISCUSSION

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

Parental buffering in the context of poverty: positive parenting behaviors differentiate young children's stress reactivity profiles

Experiencing poverty increases vulnerability for dysregulated hypothalamic–pituitary–adrenal (HPA) axis functioning and compromises long-term health. Positive parenting buffers children from HPA axis reactivity, yet this has primarily been documented among families not experiencing poverty. We tested the theorized power of positive parenting in 124 parent–child dyads recruited from Early Head Start (Mage = 25.21 months) by examining child cortisol trajectories using five samples collected across a standardized stress paradigm. Piecewise latent growth models revealed that positive parenting buffered children's stress responses when controlling for time of day, last stress task completed, and demographics. Positive parenting also interacted with income such that positive parenting was especially protective for cortisol reactivity in families experiencing greater poverty. Findings suggest that positive parenting behaviors are important for protecting children in families experiencing low income from heightened or prolonged physiologic stress reactivity to an acute stressor.

Relationships Between Pain, Life Stress, Sociodemographics, and Cortisol: Contributions of Pain Intensity and Financial Satisfaction

Objective

The relationship between psychosocial stress and chronic pain is bidirectional. An improved understanding regarding the relationships among chronic pain, life stress, and ethnicity/race will inform identification of factors contributing to health disparities in chronic pain and improve health outcomes. This study aims to assess relationships between measures of clinical pain, life stress, sociodemographics, and salivary cortisol levels.

Methods

A cross-sectional analysis involving data from 105 non-Hispanic White (NHW) and non-Hispanic Black (NHB) participants aged 45–85 years old with or at risk for knee osteoarthritis. Data included sociodemographics, clinical pain, psychosocial stress, and salivary cortisol across five time points over an approximate 12-hour period. Non-parametric correlation analysis, sociodemographic group comparisons, and regression analyses were performed.

Results

Clinical pain and psychosocial stress were associated with salivary cortisol levels, particularly morning waking and the evening to morning awakening slope. With the inclusion of recognized explanatory variables, the Graded Chronic Pain Scale characteristic pain intensity and financial satisfaction were identified as the primary pain and psychosocial measures associated with cortisol levels. Sociodemographic group differences were indicated such that NHB participants reported higher pain-related disability, higher levels of discrimination, lower financial and material satisfaction, and showed higher evening salivary cortisol levels compared to NHW participants. In combined pain and psychosocial stress analyses, greater financial satisfaction, lower pain intensity, and lower depression were associated with higher morning waking saliva cortisol levels while greater financial satisfaction was the only variable associated with greater evening to morning awakening slope.

Conclusion

Our findings show relationships among clinical pain, psychosocial stress, sociodemographic factors, and salivary cortisol levels. Importantly, with inclusion of recognized explanatory variables, financial satisfaction remained the primary factor accounting for differences in morning waking cortisol and evening to morning awakening cortisol slope in an ethnic/racially diverse group of middle aged and older adults with or at risk for knee osteoarthritis.

Associations between Effortful Control, Cortisol Awakening Response, and Depressive Problems in Latino Preadolescents

The present study examined associations between effortful control, a trait marker of self-regulation, adaptive HPA system functioning (as reflected by the CAR), and concurrent and longitudinal depressive problems, in a sample of preadolescent Latino youth (N = 119, mean age = 11.53 years, 59% female). We hypothesized that trait readiness for self-regulation (e.g., effortful control) could be related to physiological state readiness for self-regulation (e.g., CAR), and that both may counter depressive problems. We found that youth's CAR was positively associated with effortful control, and negatively with youth depressive problems. Effortful control and youth depressive problems were also negatively associated. Longitudinal relations of CAR and effortful control on depressive problems at T2 were not significant in the structural equation model after controlling for T1 depressive problems, although these variables were significant in the bivariate correlations. Results suggest that both trait-regulation and physiological regulation may counter depressive problems in Latino youth.

Racial/ethnic disparities in cortisol diurnal patterns and affect in adolescence

Racial/ethnic minorities are more vulnerable to mental and physical health problems, but we know little about the psychobiological underpinnings of these disparities. In this study, we examined racial/ethnic differences in cortisol diurnal patterns and affect as initial steps toward elucidating long-term health disparities. A racially/ethnically diverse (39.5% White, 60.5% minority) sample of 370 adolescents (57.3% female) between the ages of 11.9 and 18 years (M = 14.65 years, SD = 1.39) participated in this study. These adolescents provided 16 cortisol samples (4 samples per day across 4 days), allowing the computation of diurnal cortisol slopes, the cortisol awakening response, and diurnal cortisol output (area under the curve), as well as daily diary ratings of high-arousal and low-arousal positive and negative affect. Consistent with prior research, we found that racial/ethnic minorities (particularly African American and Latino youth) exhibited flatter diurnal cortisol slopes compared to White youth, F (1, 344.7) = 5.26, p = .02, effect size g = 0.25. Furthermore, African American and Asian American youth reported lower levels of positive affect (both high arousal and low arousal) compared to White youth. Racial/ethnic differences in affect did not explain differences in cortisol patterns, suggesting a need to refine our models of relations between affect and hypothalamic-pituitary-adrenocortical activity. We conclude by proposing that a deeper understanding of cultural development may help elucidate the complex associations between affect and hypothalamic-pituitary-adrenocortical functioning and how they explain racial/ethnic differences in both affect and stress biology.

Integrating the Neurobiology of Minority Stress with an Intersectionality Framework for LGBTQ-Latinx Populations

The comprehensive lived experiences of lesbian, gay, bisexual, transgender, and queer (LGBTQ) individuals of color remain invisible in neurobiological studies of LGBTQ populations. Models of minority stress posit that LGBTQ and Latinx individuals experience and internalize sexual, ethnic, racial, and gender discrimination, which may adversely impact mental and physical health. However, the current minority stress models predominantly focus on single categorical social identities and do not account for interlocking systems and processes of oppression based on features of sexuality, race, ethnicity, sex, and gender, as explained by an intersectionality framework in feminist theory. Thus, it remains unclear how LGBTQ people of color internalize and navigate multiple cultural, institutional, and societal stressors, and, furthermore, how these sources of stress may affect health and well-being. A potential mechanism for this adverse internalization process is through the effects of stress on neurobiological regulation. This review will apply an intersectionality framework to the examination of how heterosexism, racism, and cissexism, as systems of oppression, create LGBTQ and Latinx lived experiences, and the differential impacts of these inequalities on neurobiological stress regulation. The overarching goal of this manuscript is to advocate for the application of intersectionality theory to advance the ecological validity of biopsychosocial models of multiple-minority stress.

Cortisol response to awakening in prepubertal children and adults: Magnitude and variability

Within the first 30-45 min after awakening, there is a characteristic rise in cortisol that is referred to as cortisol awakening response (CAR). Over the past decades, the CAR has become an important biomarker, mainly because of its reported association with health and disease. Previous research showed that the CAR can already be reliably assessed in infants and children. Yet, earlier findings on the influence of age have been inconsistent, and limited attention has been devoted to prepubertal children. Here, we aimed to contrast the magnitude and stability of the CAR in prepubertal children and adults. To this end, 24 healthy adults between 35 and 50 years of age and 24 healthy children between 6 and 9 years of age collected four salivary cortisol samples within 45 min after awakening on 4 separate days, 2 weekdays, and 2 weekend days. Our results showed that there was a marked CAR on weekdays and weekend days in both adults and children. In children, however, the CAR was overall significantly attenuated relative to adults. Moreover, while the cortisol increases after awakening were, both on weekdays and weekend days, highly correlated in adults, there were no such associations in children. Together, these data suggest that the CAR is less pronounced and less stable in prepubertal children compared to adults. Such age differences need to be taken into account when using the CAR as a biomarker in clinical settings.

Perceived discrimination and cardiovascular health disparities: a multisystem review and health neuroscience perspective

There are distinct racial disparities in cardiovascular disease (CVD) risk, with Black individuals at much greater risk than White individuals. Although many factors contribute to these disparities, recent attention has focused on the role of discrimination as a stress-related factor that contributes to racial disparities in CVD. As such, it is important to understand the mechanisms by which discrimination might affect CVD. Recent studies have examined these mechanisms by focusing on neurobiological mediators of CVD risk. Given this increase in studies, a systematic review of perceived discrimination and neurobiological mediators of CVD risk is warranted. Our review uses a multisystem approach to review studies on the relationship between perceived discrimination and (1) cardiovascular responses to stress, (2) hypothalamic-pituitary-adrenocortical axis function, and (3) the immune system, as well as (4) the brain systems thought to regulate these parameters of peripheral physiology. In addition to summarizing existing evidence, our review integrates these findings into a conceptual model describing multidirectional pathways linking perceived discrimination with a CVD risk.

Hypothalamic-Pituitary-Adrenal Reactivity to Acute Stress: an Investigation into the Roles of Perceived Stress and Family Resources

Rurally situated African Americans suffer from chronic exposure to stress that may have a deleterious effect on health outcomes. Unfortunately, research on potential mechanisms that underlie health disparities affecting the African American community has received limited focus in the scientific literature. This study investigated the relationship between perceived stress, family resources, and cortisol reactivity to acute stress. A rural sample of African American emerging adults (N = 60) completed a battery of assessments, the Trier Social Stress Test (TSST), and provided four samples of salivary cortisol: prior to receiving TSST instructions, prior to conducting the speech task, immediately following the TSST, and 15-20 min following the TSST. As predicted, cortisol levels increased in response to a controlled laboratory inducement of acute stress. Moreover, diminished levels of family resources were associated with blunted cortisol reactivity to acute stress. Of note, higher levels of perceived stress over the past month and being male were independently associated with lower levels of cortisol at baseline. Lack of family resources had a blunting relationship on the hypothalamic-pituitary-adrenal axis reactivity. These findings provide biomarker support for the relationship between family resources-an indicator associated with social determinants of health-and stress physiology within a controlled laboratory experiment. Identifying mechanisms that work toward explanation of within-group differences in African American health disparities is both needed and informative for culturally informed prevention and intervention efforts.

Stress-Related Biosocial Mechanisms of Discrimination and African American Health Inequities

This review describes stress-related biological mechanisms linking interpersonal racism to life course health trajectories among African Americans. Interpersonal racism, a form of social exclusion enacted via discrimination, remains a salient issue in the lives of African Americans, and it triggers a cascade of biological processes originating as perceived social exclusion and registering as social pain. Exposure to discrimination increases sympathetic nervous system activation and upregulates the HPA axis, increasing physiological wear and tear and elevating the risks of cardiometabolic conditions. Consequently, discrimination is associated with morbidities including low birth weight, hypertension, abdominal obesity, and cardiovascular disease. Biological measures can provide important analytic tools to study the interactions between social experiences such as racial discrimination and health outcomes over the life course. We make future recommendations for the study of discrimination and health outcomes, including the integration of neuroscience, genomics, and new health technologies; interdisciplinary engagement; and the diversification of scholars engaged in biosocial inequities research.

Social context matters: Ethnicity, discrimination and stress reactivity

Exposure to chronic discrimination is associated with increased morbidity and mortality. The study of biobehavioral pathways linking discrimination with health outcomes has mostly focused on the cardiovascular system, with fewer studies addressing the hypothalamus-pituitary-adrenal (HPA) axis. In this study we tested associations between Latino ethnicity, experiences of discrimination, and cortisol responses to an acute laboratory stressor. One hundred fifty eight individuals (92 female, 66 male) between the ages of 18 and 29 years participated in the study. Salivary cortisol was measured once before and eight times after administration of a laboratory stressor (the Trier Social Stress Test). Past experiences of discrimination were measured with the Experiences of Discrimination Scale. Findings from conditional process modeling suggest that Latino ethnicity predicted a) heightened cortisol reactivity and b) more pronounced cortisol recovery through discrimination experiences (mediator), and that this effect was further moderated by sex with a significant indirect effect only among males. The direct path from Latino ethnicity to cortisol reactivity or cortisol recovery was, however, not significant. In sum, findings suggest that Latino ethnicity and discrimination interact to predict cortisol dysregulation, which implies that an appropriate model for understanding minority health discrepancies must incorporate interactive processes and cannot simply rely on the effects of ethnicity or discrimination alone.

Sleep duration partially accounts for race differences in diurnal cortisol dynamics

OBJECTIVE

Emerging research demonstrates race differences in diurnal cortisol slope, an indicator of hypothalamic-pituitary-adrenocortical (HPA)-axis functioning associated with morbidity and mortality, with African Americans showing flatter diurnal slopes than their White counterparts. Sleep characteristics are associated with both race and with HPA-axis functioning. The present report examines whether sleep duration may account for race differences in cortisol dynamics.

METHOD

Participants were 424 employed African American and White adults (mean age = 42.8 years, 84.2% White, 53.6% female) with no cardiovascular disease (Adult Health and Behavior Project-Phase 2 [AHAB-II] cohort, University of Pittsburgh). Cortisol slope was calculated using 4 salivary cortisol readings, averaged over each of 4 days. Demographic (age, sex), psychosocial (socioeconomic status [SES], affect, discrimination), and health behaviors (smoking, alcohol use, physical activity) variables were used as covariates, and sleep (self-report and accelerometry) was also assessed.

RESULTS

African Americans had flatter slopes than Whites (F(1, 411) = 10.45, B = .02, p = .001) in models adjusting for demographic, psychosocial, and health behavior covariates. Shorter actigraphy-assessed total sleep time was a second significant predictor of flatter cortisol slopes (F(1, 411) = 25.27, B = -.0002, p < .0001). Total sleep time partially accounted for the relationship between race and diurnal slope [confidence interval = .05 (lower = .014, upper .04)].

CONCLUSIONS

African Americans have flatter diurnal cortisol slopes than their White counterparts, an effect that may be partially attributable to race differences in nightly sleep duration. Sleep parameters should be considered in further research on race and cortisol. (PsycINFO Database Record

Hair cortisol and lifetime discrimination: Moderation by subjective social status

Discrimination has been associated with elevated cortisol as measured in saliva, blood, and urine. This study investigated the association between lifetime discrimination and hair cortisol concentrations, considered a measure of chronic stress. We recruited 180 young adults from diverse backgrounds. Participant responses to lifetime discrimination, home stress, and subjective status measures were recorded. Lifetime discrimination significantly predicted hair cortisol concentrations, supporting past research that discrimination experiences impact neuroendocrine systems. To our knowledge, these are the first findings associating hair cortisol concentrations with discrimination and supports prior evidence positing discrimination as a chronic stressor that serves as a risk factor for chronic disease.

Cumulative Family Stress and Diurnal Cortisol Responses in Midwest Latino Families

Latino youth and their families have been shown to experience higher levels of stressors than the general population, as well as additional unique stressors such as racism, poverty, acculturation, and discrimination. Chronic or cumulative stress often disrupts physiological systems and can lead to dysregulation in diurnal cortisol responses. This study examined the associations between family stress and cortisol responses in 57 Latino mother-adolescent dyads ( N = 114) living in the Midwestern United States. Dyads collected saliva 6 times across two consecutive days and completed a survey. Results from repeated measures mixed-effect analysis found that both mothers and adolescents in the high-stress group had flatter cortisol awakening responses than those in the low-stress group, which indicated disruptions in their diurnal cortisol rhythms. These findings suggest that family stress can potentially influence the diurnal cortisol patterns of early Latino adolescents as well as adults, which may, in turn, lead to future health problems.

Differential sensitization of parenting on early adolescent cortisol: Moderation by profiles of maternal stress

The hypothalamic-pituitary-adrenal (HPA) axis is a critical component of the body's stress-response neurobiological system, and its development and functioning are shaped by the social environment. Much of our understanding of the effects of the caregiving environment on the HPA axis is based on (a) parenting in young children and (b) individual maternal stressors, such as depression. Yet, less is known about how parenting behaviors and maternal stressors interact to influence child cortisol regulation, particularly in older children. With an ethnically diverse sample of 199 mothers and their early adolescent children (M=11.00years; 54% female), a profile analytic approach was used to investigate how multiple phenotypes of maternal stress co-occur and moderate the relation between parenting behaviors and youths' diurnal cortisol rhythms. Latent profile analysis yielded 4 profiles: current parenting stress, concurrent parenting and childhood stress, childhood stress, and low stress. For mothers with the concurrent parenting and childhood stress profile, inconsistent discipline, poor parental supervision, and harsh caregiving behaviors each were related to flattened diurnal cortisol rhythms in their adolescents. For mothers with the current parenting stress and childhood stress profiles, their use of inconsistent discipline was associated with flattened diurnal cortisol rhythms in their adolescents. For mothers with the low stress profile, none of the parenting behaviors was related to their adolescents' cortisol regulation. Findings suggest that based on mothers' stress profile, parenting behaviors are differentially related to youths' diurnal cortisol rhythms. Implications for parenting interventions are discussed.

Developmental histories of perceived racial discrimination and diurnal cortisol profiles in adulthood: A 20-year prospective study

Perceived racial discrimination (PRD) has been associated with altered diurnal cortisol rhythms in past cross-sectional research. We investigate whether developmental histories of PRD, assessed prospectively, are associated with adult diurnal cortisol profiles. One-hundred and twelve (N=50 Black, N=62 White) adults from the Maryland Adolescent Development in Context Study provided saliva samples in adulthood (at approximately age 32 years) at waking, 30min after waking, and at bedtime for 7 days. Diurnal cortisol measures were calculated, including waking cortisol levels, diurnal cortisol slopes, the cortisol awakening response (CAR), and average daily cortisol (AUC). These cortisol outcomes were predicted from measures of PRD obtained over a 20-year period beginning when individuals were in 7th grade (approximately age 12). Greater average PRD measured across the 20-year period predicted flatter adult diurnal cortisol slopes for both Black and White adults, and a lower CAR. Greater average PRD also predicted lower waking cortisol for Black, but not White adults. PRD experiences in adolescence accounted for many of these effects. When adolescent and young adult PRD are entered together predicting cortisol outcomes, PRD experiences in adolescence (but not young adulthood) significantly predicted flatter diurnal cortisol slopes for both Black and White adults. Adolescent, but not young adult PRD, also significantly predicted lower waking and lower average cortisol for Black adults. Young adult PRD was, however, a stronger predictor of the CAR, predicting a marginally lower CAR for Whites, and a significantly larger CAR for Blacks. Effects were robust to controlling for covariates including health behaviors, depression, income and parent education levels. PRD experiences interacted with parent education and income to predict aspects of the diurnal cortisol rhythm. Although these results suggest PRD influences on cortisol for both Blacks and Whites, the key findings suggest that the effects are more pervasive for Blacks, affecting multiple aspects of the cortisol diurnal rhythm. In addition, adolescence is a more sensitive developmental period than adulthood for the impacts of PRD on adult stress biology.

Race Effects on Conditioned Pain Modulation in Youth

Race and ethnicity shape the experience of pain in adults. African Americans typically exhibit greater pain intensity and evoked pain responsiveness than non-Hispanic whites. However, it remains unclear whether there are racial differences in conditioned pain modulation (CPM) and if these are present in youth. CPM refers to a reduction in perceived pain intensity for a test stimulus during application of a conditioning stimulus and may be especially relevant in determining risk for chronic pain. The present study assessed CPM to evoked thermal pain in 78 healthy youth (ages 10-17 years), 51% of whom were African American and 49% of whom were non-Hispanic white. African American youth reported lower mean conditioning pain ratings than non-Hispanic white youth, controlling for mean preconditioning pain ratings, which is consistent with stronger CPM. Multilevel models demonstrated stronger CPM effects in African American than non-Hispanic white youth, as evident in more rapid within-person decreases in pain ratings during the conditioning phase. These findings suggest that diminished CPM likely does not account for the enhanced responsiveness to evoked thermal pain observed in African American youth. These results may have implications for understanding racial differences in chronic pain experienced in adulthood. Perspective: This study evaluated conditioned pain modulation to evoked thermal pain in African American and non-Hispanic white youth. Findings could have implications for the development of personalized chronic pain treatment strategies that are informed by race and ethnicity.

The developmental course of salivary alpha-amylase and cortisol from 12 to 36 months: Relations with early poverty and later behavior problems

This study examined the development of baseline autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) physiological activity from 12 to 36 months as well as antecedents (poverty) and consequents (behavior problems) of individual differences in physiological development. Children (N=179; 50% poor; 56% African American; 52% male) provided saliva samples at 12, 18, 24, 30, and 36 months of age. Latent growth curve models indicated that nonlinear change was evident for both sAA and cortisol, with sAA increasing and cortisol decreasing with age. Children residing in poor households exhibited lower initial levels of sAA, but not cortisol. African-American children showed slightly smaller decreases in cortisol over time. Initial levels of sAA predicted higher levels of internalizing behaviors at 36 months and both initial levels of and total change in sAA predicted higher levels of externalizing behaviors at 36 months. There was no evidence that sAA or cortisol mediated the relationship between poverty and later behavior problems.

Short-Term Resilience Processes in the Family

The authors review naturalistic studies of short-term processes that appear to promote resilience in children in the context of everyday family life and argue that warm and supportive family interactions foster resilience through their cumulative impact on children's emotional and physiological stress response systems. In the short-term, these family interactions promote the experience and expression of positive emotion and healthy patterns of diurnal cortisol. Over time, these internal resources - a propensity to experience positive emotion and a well-functioning hypothalamic-pituitary-adrenal axis system -enhance a child's capacity to avoid, or limit, the deleterious effects of adversity. This article highlights naturalistic research methods that are well suited to the study of these short-term resilience processes and points to clinical applications of our conceptual and methodological approach.

Associations between coping and diurnal cortisol among children affected by parental HIV/AIDS

OBJECTIVE

Prior research has shown that early life adversity is associated with physical health problems, but little is known about the health-related effects of coping in the context of having a parent with HIV/AIDS. The goal of this study was to investigate the associations between positive and negative coping strategies and diurnal cortisol among children affected by parental HIV/AIDS.

METHOD

Participants were 645 children aged 8-15 affected by parental HIV/AIDS, who provided 4 saliva samples per day over 3 days (2 weekdays and 1 weekend day) to assess diurnal cortisol. Positive and negative coping strategies were measured via self-report prior to saliva collection. Possible confounds of the associations between coping and diurnal cortisol also were assessed, including age, gender, socioeconomic status, parenting quality, parental death, other stressful life events, sleep quality, and perceived health status.

RESULTS

Greater positive coping (e.g., problem solving, cognitive reframing) was associated with children's higher morning cortisol (p = .037), whereas greater negative coping (e.g., fighting, breaking things) was independently associated with lower morning cortisol (p = .038) and a flatter diurnal cortisol slope (p = .003). These associations remained significant after controlling for potential confounds. Neither positive coping nor negative coping interacted with stressful life circumstances to predict cortisol (all ps > .27).

CONCLUSION

These findings indicate the extent to which a child's coping strategy is associated with indicators of stress biology in the context of having a parent with HIV/AIDS.

"More than skin deep": stress neurobiology and mental health consequences of racial discrimination

Ethnic minority groups across the world face a complex set of adverse social and psychological challenges linked to their minority status, often involving racial discrimination. Racial discrimination is increasingly recognized as an important contributing factor to health disparities among non-dominant ethnic minorities. A growing body of literature has recognized these health disparities and has investigated the relationship between racial discrimination and poor health outcomes. Chronically elevated cortisol levels and a dysregulated hypothalamic-pituitary-adrenal (HPA) axis appear to mediate effects of racial discrimination on allostatic load and disease. Racial discrimination seems to converge on the anterior cingulate cortex (ACC) and may impair the function of the prefrontal cortex (PFC), hence showing substantial similarities to chronic social stress. This review provides a summary of recent literature on hormonal and neural effects of racial discrimination and a synthesis of potential neurobiological pathways by which discrimination affects mental health.

Child diurnal cortisol rhythms, parenting quality, and externalizing behaviors in preadolescence

This study examined a neurobiologically informed model of the emergence of child externalizing behaviors in an ethnically diverse community sample of 232 9-12 year old children. Replicating extensive prior research, our analyses revealed that parents' inconsistent discipline and poor quality monitoring were predictive of child externalizing behavior. In addition, poor parental monitoring, but not inconsistent discipline, was associated with children having a significantly flatter morning-to-evening cortisol slope, which was in turn, related to higher levels of externalizing behaviors. An indirect effect of parental monitoring on externalizing behaviors, through child diurnal cortisol rhythms, was also supported. These findings highlight the role of the hypothalamic-pituitary-adrenal (HPA) axis and its hormonal end product, cortisol, in the relationship between the caregiving environment and the development of externalizing behaviors.

The association between cortisol and neighborhood disadvantage in a U.S. population-based sample of adolescents

The association between neighborhood conditions and cortisol is rarely studied in children or adolescents and has been hampered by small sample size and racial/ethnic and geographic homogeneity. Our objective was to estimate the association between neighborhood disadvantage and salivary cortisol levels in a large, geographically and racially/ethnically diverse sample of adolescents from the National Comorbidity Survey Replication Adolescent Supplement. Salivary cortisol was collected before and after an interview administered in the adolescent's home. We used a propensity score approach to match adolescents living in disadvantaged neighborhoods with those in non-disadvantaged neighborhoods to create two similar groups based on the time and day of cortisol collection as well as demographic characteristics. Adolescents living in disadvantaged neighborhoods had higher pre-interview cortisol levels and steeper rates of decline in cortisol levels over the course of the interview than similar adolescents in non-disadvantaged neighborhoods. This bolsters the evidence base suggesting that place may influence the stress response system.

Age-dependent and gender-dependent regulation of hypothalamic-adrenocorticotropic-adrenal axis

Tightly regulated output of glucocorticoids is critical to maintaining immune competence, the structure of neurons, muscle, and bone, blood pressure, glucose homeostasis, work capacity, and vitality in the human and experimental animal. Age, sex steroids, gender, stress, body composition, and disease govern glucocorticoid availability through incompletely understood mechanisms. According to an ensemble concept of neuroendocrine regulation, successful stress adaptations require repeated incremental signaling adjustments among hypothalamic corticotropin-releasing hormone and arginine vasopressin, pituitary adrenocorticotropic hormone, and adrenal corticosteroids. Signals are transduced via (positive) feedforward and (negative) feedback effects. Age and gonadal steroids strongly modulate stress-adaptive glucocorticoid secretion by such interlinked pathways.