Variation in hypothalamic-pituitary-adrenal axis activity among bullied and non-bullied children

Do Hormone Levels Influence Bullying during Childhood and Adolescence? A Systematic Review of the Literature

(1) Background: Bullying is one of the most common forms of aggressive behavior during childhood and adolescence. Some decades ago, researchers began exploring the basis of peer victimization from a biological perspective. Specifically, the Hypothalamic-Pituitary-Adrenal (HPA) and Hypothalamic-Pituitary-Gonadal (HPG) axes have been studied in relation to status-relevant behaviors, such as bullying. (2) Methods: We conducted a systematic review following the PRISMA guide and registered the review protocol at PROSPERO (CRD42023494738). We searched for relevant studies in PubMed, Psycinfo, Scopus, and Web of Science, and assessed them using the Robins E-tool. (3) Results: Our search yielded 152 studies, of which 33 were included in the review. These studies explored the association between testosterone and cortisol levels with bullying behavior, finding diverse results. Most of the studies were rated as having a low risk of bias. (4) Conclusions: This study not only enhances our understanding of bullying, but also provides guidance for the development of prevention and management programs for it. In the future, researchers should continue exploring the joint effects of different hormones on the HPA and HPG axis, using a broader set of biomarkers.

War exposure, post-traumatic stress symptoms and hair cortisol concentrations in Syrian refugee children

Altered secretion of cortisol, the primary effector of the hypothalamus-pituitary-adrenal axis, has been proposed as a means by which traumatic experiences compromise later mental health. However, despite the popularity of cortisol as a potential biomarker for stress and adversity, findings are inconsistent, and little is known about the impact of war-related trauma on stress physiology of children and adolescents. Here we aimed to evaluate the relationships between war exposure, current living conditions, hair cortisol concentrations (HCC) and post-traumatic stress disorder (PTSD) symptoms in a large cohort of Syrian refugee children and adolescents (6-18 years) and their caregiver. This longitudinal observational study assessed Syrian refugee children and adolescents in two waves, 1 year apart, within informal tented settlements in Lebanon. The relationships between war exposure, time since leaving Syria, PTSD symptoms and HCC were investigated using linear mixed-model regression utilising both waves of data collected (Y1: N = 1574, Y2: N = 923). Hair cortisol concentration was positively, but weakly associated with the number of war-related events experienced. This was limited to those who were at least 12 years old at the time of war exposure. Conversely, HCC decreased with time since leaving Syria. HCC was also associated with PTSD symptoms but not with the quality of their current living conditions. This study revealed that changes to hypothalamic-pituitary-adrenal axis activity may accompany both earlier war exposure and current PTSD symptoms in children and adolescents. Additionally, early adolescence may be a particularly sensitive time in terms of trauma-related changes to the hypothalamic-pituitary-adrenal axis.

Gender-Specific Significance of Peer Abuse during Childhood and Adolescence on Physical and Mental Health in Adulthood-Results from a Cross-Sectional Study in a Sample of Hospital Patients

Peer abuse (PA) is a widespread and gender-sensitive form of Adverse Childhood Experiences (ACEs). However, research on its influence on physical and mental health in adulthood remains scarce. The aim of this study was to investigate gender-specific associations between PA and physical and mental health in adulthood in a sample of general hospital patients. A cross-sectional study at the University Hospital of Innsbruck was conducted. Data on ACEs, physical and mental health were collected using self-report questionnaires. We compared patients with no ACEs, PA only, ACEs without PA, and ACEs with PA using gender-specific binary logistic regressions to investigate the association of PA with physical and mental health. A total of 2,392 patients were included in the analyses. Women reported more emotional PA (13.1% vs. 9.4%; p = 0.006), while men reported more physical PA (8.3% vs. 5.2%; p = 0.003). PA was associated with a higher likelihood for depression (OR = 2.6), somatization (OR = 2.1), as well as worse physical health (OR = 2.1) in women but not in men. This study is the first to present data on the gender-specific detrimental effect of PA on physical and mental health in adulthood. Especially for women, PA poses a significant health risk. Thus, we should be aware of these effects and offer adequate support for affected individuals.

Hair cortisol as a biomarker of chronic stress in preadolescents: influence of school context and bullying

Bullying has been identified as the most common form of aggression and a major source of stress among children and adolescents. The main objective of this study was to analyze the association that school context in general and bullying in particular might have with hair cortisol concentration (HCC), examining the effect of executive function and sex on this association. The study included 659 11-year-old preadolescents from the cohorts of Gipuzkoa and Sabadell of the INMA (INfancia y Medio Ambiente-Children and Environment) project. We gathered information about school-related factors (bullying, school environment, problems with peers and academic performance) and executive function (risky decision-making). Hair samples were collected to measure cortisol concentrations and Structural Equation Modeling was used to examine associations between school-related factors, executive function and HCC. Results showed that being involved as a bully/victim was related to higher HCC and, higher HCC was associated with poorer executive function. This study may contribute to a better understanding of the consequences that chronic exposure to a stressful factors may have on preadolescents' health and developmental outcomes. Besides, our results are relevant for designing programs for prevention and intervention, which could modify individual physiological responses to stress and reduce the effects of stress on the health.

Do prepubertal hormones, 2D:4D index and psychosocial context jointly explain 11-year-old preadolescents' involvement in bullying?

BACKGROUND

Bullying is a type of aggressive behavior that occurs repeatedly and intentionally in school environments and where there is a power imbalance. The main objective of this study was to analyze the association that hormones and the psychosocial context jointly have with bullying behavior.

METHOD

Participants were 302 11-year-old preadolescents from the Gipuzkoan cohort of the INMA Project. Bullying was assessed using the Olweus Bully/victim Questionnaire. Prenatal sexual hormones were assessed by calculating 2D:4D ratio and in order to measure prepubertal testosterone and cortisol levels saliva samples were collected within a week of each other. Additionally, various psychosocial factors were evaluated: executive function, family context, school environment and social context. To analyze our complex hypothesis, six metamodels were tested using structural equation modeling.

RESULTS

In relation to victims, results showed that victimization was related to worse school environment' perception in boys, and higher stress and conflict in the family in girls. In the case of their involvement in bullying as a bully, lower salivary cortisol levels, worse school environment' perception and lower peers and social support was related to being more frequently involved as a bully in boys, while having more family stress and conflict was related with being a bully in girls.

CONCLUSIONS

This approach makes it possible not only to explore the different biological and psychosocial factors affect bullying behavior, but also to explore associations between the predictor variables.

Under the skin: does psychiatric outcome of bullying victimization in school persist over time? A prospective intervention study

BACKGROUND

Research has shown a direct path between peer victimization and poor mental health outcomes. However, the impact of bullying prevention on mental health is a largely unexplored field. Therefore, our study examined the longitudinal association between bullying development and trajectories of psychiatric symptoms (emotional problems, total difficulties, nonsuicidal self-injury, and suicidality) and health-related quality of life (HRQL) during the implementation of school-based bullying prevention.

METHODS

Data of 4,873 pupils (grades 5-13) were collected in 23 schools implementing the Olweus Bullying Prevention Program (OBPP). Self-report questionnaires were administered at three annual assessment waves and individual codes enabled the association of repeated assessments to the same pupil. Latent growth curve models (LGCMs) were used to examine the relation among bullying status and mental health outcome with mixed-effects linear regressions estimating the association of changes in bullying with changes in continuous scores and mixed-effects logistic regressions for categorical variables.

RESULTS

Latent growth curve models revealed an improvement of mental health and HRQL through the termination of bullying for every outcome variable of interest (all p < .001). Correspondingly, we found an explicit increase in psychopathology as well as decrease in HRQL within one year as a result of developing victimization (all p < .001). Interestingly, the growth of psychopathology associated with the onset of bullying was significantly steeper than its decline associated with the termination of bullying. The postulated cumulative effect of ongoing bullying for a further year could only be shown for HRQL (p = .025) and total difficulties (p = .034), but not for specific mental health problems (all p > .117).

CONCLUSIONS

Latent growth curve models clearly showed that the adverse psychosocial consequences of bullying arise quickly but seem to reduce much slower and partly persist over time. Future long-term studies are necessary to clarify if mental health problems will return to baseline after several years or if residual symptoms will remain.

The Unique Contribution of Past Bullying Experiences to the Presence of Psychosis-Like Experiences in University Students

OBJECTIVES

Both bullying and psychosis-like experiences (PLEs) have gained much attention in recent years, but their interactions are not fully unraveled. The aim of the current study was to validate the Chinese version of Bullying Scale for Adults (C-BSA), and to investigate whether past bullying experiences independently predict the presence of PLEs in university students.

METHODS

The validity and reliability of the C-BSA were determined in two independent samples. A battery of psychological inventories was also administered to assess the presence of PLEs, maltreatment history in the family, and current depression and anxiety, including the 15-item positive subscale of the community assessment of psychic experiences (CAPE-p15), the Chinese version of the Childhood Trauma Questionnaire (CTQ), Self-Rating Depression Scale (SDS), and Self-Rating Anxiety Scale (SAS).

RESULTS

In the construction sample (N = 629), a Cronbach's α of 0.921 indicated a good internal consistency of C-BSA. The exploratory factor analysis (EFA) yielded a four-factor model and a three-factor model, and both were verified by using the confirmatory factorial analysis (CFA) in the validation sample (N = 629). The total scores of C-BSA were significantly correlated with that of CTQ, CAPE-p15, SDS, and SAS. Multivariate logistic regression revealed that bullying was associated with 2.0 or 3.7 times of risk for the presence of PLEs (numbers of bullying types < = 3 or > 3, respectively) after controlling for CTQ, SDS, and SAS scores.

CONCLUSIONS

C-BSA has shown good psychometric properties in college students. The contribution of past bullying experiences to the present PLEs seems to be independent of other childhood trauma, current depression, and anxiety.

Prior night sleep moderates the daily spillover between conflict with peers and family and diurnal cortisol

We investigated whether daily experiences of conflict with family and peers were associated with fluctuations in diurnal cortisol, and whether sleep buffers the associations between conflict and diurnal cortisol. A racially diverse sample of 370 adolescents (ages 11-18; 57.3% female) provided daily diaries for 5 days and saliva samples for 4 days. Hierarchical linear models tested how peer and family conflict were associated with diurnal cortisol (i.e., total cortisol output, cortisol slope, and cortisol awakening response) the next day, and whether these associations were moderated by sleep duration the previous night. When adolescents experienced peer conflict, they showed higher area under the curve (AUC) the next day if they had slept less the night prior to conflict, but relatively lower cortisol awakening response (CAR) and flatter cortisol slope the next day if they had slept more the night prior to conflict. When adolescents experienced family conflict, they also showed higher AUC the next day if they had slept less the night prior to conflict, but higher CAR the next day if they had slept more the night prior to conflict. Family conflict and sleep were not directly or interactively related to cortisol slope.

Indirect effects of HPA axis dysregulation in the association between peer victimization and depressed affect during early adolescence

OBJECTIVE

Previous research has identified a link between peer victimization and depressive symptoms during adolescence. The goal of the current study is to examine the possible indirect effects of HPA axis dysregulation in the link between adolescent peer victimization and depressive symptoms.

METHOD

A total of 113 boys (n = 61) and girls (n = 52) participants from grade 5 (M age = 10.31 years) and grade 6 (M age = 11.33 years) who were predominantly European-Canadian completed self-report measures of peer victimization and depressed affect as well as, measures of salivary cortisol and self-reports of negative experiences collected in conjunction with one another five times per day over the course of four school days.

RESULTS

Multi-level structural equation modeling found that peer victimization was indirectly associated with depressive symptoms via blunted cortisol reactivity (i.e. increases in cortisol in response to a negative event) but only at high rates of chronic peer victimization.

CONCLUSION

The findings suggest that future studies should focus on HPA axis dysregulation for better understand the development, as well as the stability of depression over time and that interventions targeting peer victimization may want to put a special focus on those who are chronically experiencing peer victimization over time.

Adverse Childhood Events and Health Biomarkers: A Systematic Review

Background: This systematic review aimed to summarize evidence reporting epigenetic and/or neuro-immuno-endocrine embedding of adverse childhood events (ACEs) in children, with a particular focus on the short-term biological effect of those experiences.

Methods: A search was conducted in PsycINFO®, PubMed®, Isi Web of Knowledge and Scopus, until July 2019, to identify papers reporting the short-term biological effects of exposure to ACEs.

Results: The search identified 58 studies, that were included in the review. Regarding exposure, the type of ACE more frequently reported was sexual abuse (n = 26), followed by life stressors (n = 20) and physical abuse (n = 19). The majority (n = 17) of studies showed a positive association between ACEs and biomarkers of the immune system. Regarding DNA methylation 18 studies showed more methylation in participants exposed to ACEs. Two studies presented the effect of ACEs on telomere length and showed that exposure was associated with shorter telomere length.

Conclusion: Overall the associations observed across studies followed the hypothesis that ACEs are associated with biological risk already at early ages. This is supporting evidence that ACEs appear to get “under the skin” and induce physiological changes and these alterations might be strongly associated with later development of disease.

Daily provision of instrumental and emotional support to friends is associated with diurnal cortisol during adolescence

This study investigates how adolescents' daily prosocial behaviors to friends are related to diurnal cortisol using between- and within-subject analyses. Further, we examine whether role fulfillment (i.e., feeling like a good friend) moderates links between prosocial behaviors and cortisol. Ethnically diverse adolescents (N = 370; ages 11-18) reported whether they provided instrumental and emotional support to friends for 5 days, and provided four saliva samples/day for 4 days. On the daily level, providing emotional support predicted lower cortisol awakening response the next day, and providing instrumental assistance to friends was associated with a flatter cortisol slope the same day (a cardiovascular risk factor). Adolescents also provided more emotional support on days they had lower CAR and steeper cortisol slopes. On the average level, providing more instrumental support was associated with steeper cortisol slopes among adolescents who felt high levels of role fulfillment, but not among adolescents who felt low levels of role fulfillment. Providing instrumental support may be physiologically taxing from day to day but, across the long term, linked to lower cardiovascular risk for adolescents who experience helping as highly fulfilling.

Gender is Key: Girls' and Boys' Cortisol Differs as a Factor of Socioeconomic Status and Social Experiences During Early Adolescence

The risks associated with negative peer relationships and low socioeconomic status (SES), and how they impact diurnal cortisol and the cortisol response to negative experiences, have never been studied together in early adolescents; this study aims to fill this gap in the literature. Saliva was collected from 95 early adolescents (M_age = 10.80, SD = 0.72) and daily diaries were completed 30 min after awakening, beginning of school, 15 min after first recess, 15 min after lunch, and at the end of the school day across four consecutive days. Hierarchical Linear Modelling was used to estimate the within- and between-person variances of diurnal cortisol and the cortisol response to stress in the context of SES and peer experiences. Cortisol secretion differed by gender and was predicted by SES and social status within the peer group. Low-SES early adolescents had higher morning cortisol. Girls who were from higher SES families had the steepest diurnal cortisol slope. Non-accepted early adolescents had low cortisol in response to both positive and negative social experiences. The findings from this study clarify the impact of both SES and peer relations on early adolescent psychophysiological development.

Associations between developmental trajectories of peer victimization, hair cortisol, and depressive symptoms: a longitudinal study

BACKGROUND

Peer victimization has been associated with long-lasting risks for mental health. Prior research suggests that stress-related systems underlying adaptation to changing environments may be at play. To date, inconsistent findings have been reported for the hypothalamic-pituitary-adrenal (HPA) axis, and its end product cortisol. This study tested whether peer victimization was associated with hair cortisol concentrations (HCC), and whether this association varied according to sex, timing, and changes in exposure. We also examined whether peer victimization differentially predicted depressive symptoms according to HCC.

METHODS

The sample comprised 556 adolescents (42.0%; 231 males) who provided hair for cortisol measurement at 17 years of age. Peer victimization was reported at seven occasions between the ages of 6 and 15 years.

RESULTS

Peer victimization was nonlinearly associated with HCC for boys only, whereas changes in peer victimization were related to HCC for boys and girls. Peer victimization predicted more depressive symptoms for all participants, except those with lower HCC.

CONCLUSIONS

Our findings provide further support for persistent dysregulation of the HPA axis following exposure to chronic adversity, of which the expression may change according to sex and the severity of victimization.

Future Directions in Peer Relations Research

Peer relationships among youth have been examined as predictors of mental health outcomes for at least fifty years, revealing dozens of discrete peer constructs that each are associated with adjustment in childhood, adolescence, and later in adulthood. Future research may benefit by examining a range of new outcomes and psychological processes that have been discussed recently in related literatures. This paper reviews recent research on interpersonal determinants of physical health outcomes, and opportunities for greater examination of 1) peer influence processes toward health risk behaviors; 2) neural correlates of peer adversity; 3) adverse peer experiences that may affect physiological markers of stress response; and 4) immune system markers of peer adversity. Additional future directions include the study of differences in the forms and functions of peer interactions within the digital age.

Early Life Stress and Pediatric Posttraumatic Stress Disorder

Traumatic stress exposure during critical periods of development may have essential and long-lasting effects on the physical and mental health of individuals. Two thirds of youth are exposed to potentially traumatic experiences by the age of 17, and approximately 5% of adolescents meet lifetime criteria for posttraumatic stress disorder (PTSD). The role of the stress system is the maintenance of homeostasis in the presence of real/perceived and acute/chronic stressors. Early-life stress (ELS) has an impact on neuronal brain networks involved in stress reactions, and could exert a programming effect on glucocorticoid signaling. Studies on pediatric PTSD reveal diverse neuroendocrine responses to adverse events and related long-term neuroendocrine and epigenetic alterations. Neuroendocrine, neuroimaging, and genetic studies in children with PTSD and ELS experiences are crucial in understanding risk and resilience factors, and also the natural history of PTSD.

Bullying Victimization and Trauma

Bullying victimization and trauma research traditions operate quite separately. Hence, it is unclear from the literature whether bullying victimization should be considered as a form of interpersonal trauma. We review studies that connect bullying victimization with symptoms of PTSD, and in doing so, demonstrate that a conceptual understanding of the consequences of childhood bullying needs to be framed within a developmental perspective. We discuss two potential diagnoses that ought to be considered in the context of bullying victimization: (1) developmental trauma disorder, which was suggested but not accepted as a new diagnosis in the DSM-5 and (2) complex post-traumatic stress disorder, which has been included in the ICD-11. Our conclusion is that these frameworks capture the complexity of the symptoms associated with bullying victimization better than PTSD. We encourage practitioners to understand how exposure to bullying interacts with development at different ages when addressing the consequences for targets and when designing interventions that account for the duration, intensity, and sequelae of this type of interpersonal trauma.

Health consequences of bullying in the healthcare workplace: A systematic review

AIMS

To review both mental and physical health consequences of bullying for healthcare employees.

DESIGN

Systematic literature review.

DATA SOURCES

EMBASE, MEDLINE, PsycINFO, PUBMED and Web of Science Core Collection were searched for articles published between 2005 - January 2017.

REVIEW METHODS

This review was conducted using the framework described by Khan and reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Two independent reviewers performed systematic data extraction and appraised the methodological quality of included articles. A pooled mean prevalence of bullying was estimated.

RESULTS

Forty-five papers met inclusion criteria. Bullying prevalence ranged from 3.9% to 86.5%, with a pooled mean estimate of 26.3%. Perceived bullying was associated with mental health problems including psychological distress, depression and burnout, and physical health problems including insomnia and headache. Bullied staff took more sick leave.

CONCLUSION

Bullying occurs frequently amongst healthcare staff and is deleterious to health and occupational functionality.

Qualitative and Quantitative Evaluation of the Efficiency of the Application of Foams with False Xerostomia

Aims:

Xerostomia syndrome is a significant medical and social problem. It is manifested by objective and subjective symptoms of a “dry mouth” and a decrease in sialometry. The aim of the study was to determine the dental status of students of different nationalities, to identify xerostomia induced on a background of stress, and to assess the effectiveness of the use of moisturizing foams in alleviating xerostomia.

Materials and Methods:

A prospective cohort study survey (Fox test) of 100 students of the dental faculty was conducted to detect false xerostomia. The study involved 60 people with false xerostomia, divided into four groups of 15 each according to the nationality. The level of oral hygiene was determined using the Simplified Oral Hygiene and Silness-Loe indices and the rate of salivation was assessed with sialometry method by Pozharitskaya. Oral hygiene instructions were given to the participants. They were to apply moisturizing foams with lactoferrin, lactoperoxidase, and aloe vera, two–three times during the day for 3 weeks. A set of statistical programs was used (Microsoft Excel [2007] and the Statistical Package for the Social Sciences [SPSS], version 23) to perform Kolmogorov–Smirnov, Shapiro–Wilk, Kruskal–Wallis, and Wilcoxon tests.

Results:

A statistically significant improvement in oral hygiene was observed in all study participants. A significant increase was detected in the rate of salivation in students from Russia (P = 0.005), Transcaucasian countries (P = 0.006), and Arab countries (P = 0.005).

Conclusion:

It has been established that the use of moisturizing foam has a positive effect on the rate of salivation and improves the level of oral hygiene, thereby improving the quality of life for patients.

Childhood adversity and mechanistic links to hypertension risk in adulthood

Adverse childhood experiences (ACEs), defined as traumatic events in childhood that range from various forms of abuse to household challenges and dysfunction, have devastating consequences on adult health. Epidemiological studies in humans and animal models of early life stress (ELS) have revealed a strong association and insight into the mechanistic link between ACEs and increased risk of cardiovascular disease (CVD). This review focuses on the mechanistic links of ACEs in humans and ELS in mice and rats to vasoactive factors and immune mediators associated with CVD and hypertension risk, as well as sex differences in these phenomena. Major topics of discussion in this review are as follows: (a) epidemiological associations between ACEs and CVD risk focusing on hypertension, (b) evidence for association of ACE exposures to immune-mediated and/or vasoactive pathways, (c) rodent models of ELS-induced hypertension risk, (d) proinflammatory mediators and vasoactive factors as mechanisms of ELS-induced hypertension risk. We also provide some overall conclusions and directions of further research. LINKED ARTICLES: This article is part of a themed section on Immune Targets in Hypertension. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.12/issuetoc.

Effects of preferred music therapy on peer attachment, depression, and salivary cortisol among early adolescents in Taiwan

AIMS

To explore the effects of preferred music therapy on peer attachment, depression, and salivary cortisol among early adolescents.

BACKGROUND

As adolescents enter puberty, they start to seek partnering relationships among peers. Peer attachment is central for adolescents and greatly influences their physical and psychological development.

DESIGN

A pre-test-posttest control group design.

METHODS

The data were collected from July - October 2016. A total of 65 individuals were included. The treatment group received 40 min of music therapy twice per week over the course of 10 weeks. The control group maintained its typical routine. The research data were collected using structured questionnaires, including basic information, the Inventory of Peer Attachment, the Beck Depression Inventory-II questionnaires, and salivary cortisol concentrations. Statistical analysis methods included percentages, chi-square tests, t tests, analyses of covariance, and the Johnson-Neyman technique.

RESULTS

There were statistically significant differences in peer attachment, depression, and salivary cortisol levels in the music group compared to the control group (p < 0.05). Additionally, the findings showed that early adolescents with more severe depression experienced greater improvement through preferred music therapy.

CONCLUSION

The results allude to the beneficial effects of receiving preferred music therapy in terms of the peer attachment, depression, and salivary cortisol levels of early adolescents. Adjustments should be made based on the characteristics of student groups to develop suitable and safe music therapy and to reduce the risks of poor mental health.

Age and sex differences in the effects of peer victimization on depressive symptoms: Exploring sleep problems as a mediator

BACKGROUND

Peer victimization contributes to an elevated risk of adolescent depression. Although theoretical evidence has noted that peer victimization may disrupt sleep and subsequently increase levels of depressive symptoms, this pathway has never been tested. This study explores a novel mechanism leading from peer victimization to depressive symptoms through sleep problems and considers whether the direct and indirect pathways vary by age and sex of adolescents.

METHODS

Data were from 4072 adolescents (2042 males, 2030 females; age range 14-19 years) residing in northern Taiwan. Mediation analyses were first conducted to understand the mediating role of sleep problems in the association between peer victimization and depressive symptoms for males and females, respectively. Moderated mediation analyses were then applied to test age differences in the direct and indirect pathways from peer victimization to depressive symptoms.

RESULTS

Sleep problems mediated the association between peer victimization and depressive symptoms in adolescent females but not in males. Age further moderated the indirect pathway from peer victimization to depressive symptoms through sleep problems, such that the mediating effects of sleep problems increased with age and were only significant in older females. No age differences were observed for the direct effects of peer victimization on depressive symptoms in either males or females.

LIMITATIONS

Study was not designed to infer causality and all variables were assessed by self-report measures.

CONCLUSIONS

Our analyses revealed age and sex differences in the link from peer victimization to depressive symptoms through sleep problems. Efforts to reduce depressive symptoms in adolescent females who have experienced peer victimization may be made more effective by targeting sleep problems, especially in older female adolescents.

Bullying the Brain? Longitudinal Links Between Childhood Peer Victimization, Cortisol, and Adolescent Brain Structure

Background: Childhood peer victimization is a stressful life experience associated with long-lasting adverse psychological consequences. While there is some evidence that victimization is associated with alterations in brain function, little is known about effects on brain structure. This study explored the relationships between childhood peer victimization, cortisol, and adolescent ventrolateral prefrontal cortex (vlPFC) structure in a sample of healthy children.

Methods: A total of 50 (M_age = 9.29 years at baseline) children participated in this longitudinal study. We examined whether diurnal cortisol levels (assessed at baseline) moderated the link between children’s self-reported peer victimization (assessed at baseline) and vlPFC surface area, gray matter volume, and thickness 5 years later.

Results: For boys, cortisol levels moderated the association between victimization and brain structure. For boys with a low daily cortisol output (assessed as area under the curve; AUC), high victimization was associated with a smaller right vlPFC surface area, and for boys with a high AUC, high victimization was associated with a larger right vlPFC surface area. In addition, for boys with a steeper diurnal slope, high victimization was associated with a smaller right vlPFC surface area, and for boys with a low flatter diurnal slope, high victimization was associated with a larger right vlPFC surface area.

Conclusion: These results indicate the differential influence of cortisol on the relationship between victimization and brain structure. Findings suggest that victimization may have differential effects on brain development in boys who are more versus less biologically sensitive to stress.

Developmental Trajectories of Early Life Stress and Trauma: A Narrative Review on Neurobiological Aspects Beyond Stress System Dysregulation

Early life stressors display a high universal prevalence and constitute a major public health problem. Prolonged psychoneurobiological alterations as sequelae of early life stress (ELS) could represent a developmental risk factor and mediate risk for disease, leading to higher physical and mental morbidity rates in later life. ELS could exert a programming effect on sensitive neuronal brain networks related to the stress response during critical periods of development and thus lead to enduring hyper- or hypo-activation of the stress system and altered glucocorticoid signaling. In addition, alterations in emotional and autonomic reactivity, circadian rhythm disruption, functional and structural changes in the brain, as well as immune and metabolic dysregulation have been lately identified as important risk factors for a chronically impaired homeostatic balance after ELS. Furthermore, human genetic background and epigenetic modifications through stress-related gene expression could interact with these alterations and explain inter-individual variation in vulnerability or resilience to stress. This narrative review presents relevant evidence from mainly human research on the ten most acknowledged neurobiological allostatic pathways exerting enduring adverse effects of ELS even decades later (hypothalamic-pituitary-adrenal axis, autonomic nervous system, immune system and inflammation, oxidative stress, cardiovascular system, gut microbiome, sleep and circadian system, genetics, epigenetics, structural, and functional brain correlates). Although most findings back a causal relation between ELS and psychobiological maladjustment in later life, the precise developmental trajectories and their temporal coincidence has not been elucidated as yet. Future studies should prospectively investigate putative mediators and their temporal sequence, while considering the potentially delayed time-frame for their phenotypical expression. Better screening strategies for ELS are needed for a better individual prevention and treatment.

Early life stress and trauma: developmental neuroendocrine aspects of prolonged stress system dysregulation

Experience of early life stress (ELS) and trauma is highly prevalent in the general population and has a high public health impact, as it can trigger a health-related risk cascade and lead to impaired homeostatic balance and elevated cacostatic load even decades later. The prolonged neuropsychobiological impact of ELS can, thus, be conceptualized as a common developmental risk factor for disease associated with increased physical and mental morbidity in later life. ELS during critical periods of brain development with elevated neuroplasticity could exert a programming effect on particular neuronal networks related to the stress response and lead to enduring neuroendocrine alterations, i.e., hyper- or hypoactivation of the stress system, associated with adult hypothalamic-pituitary-adrenal axis and glucocorticoid signaling dysregulation. This paper reviews the pathophysiology of the human stress response and provides evidence from human research on the most acknowledged stress axis-related neuroendocrine pathways exerting the enduring adverse effects of ELS and mediating the cumulative long-term risk of disease vulnerability in adulthood.

Peer victimization and diurnal cortisol rhythm among children affected by parental HIV: Mediating effects of emotional regulation and gender differences

The hypothalamic-pituitary-adrenal (HPA) axis activity has been demonstrated as one of the physiological mechanisms underlying the long-lasting effects of peer victimization on physical and mental health. However, the mechanisms linking peer victimization to dysregulations of HPA axis activity remain inadequately understood. The present study examined the potential mediating role of emotional regulation in the association between peer victimization and HPA axis activity in a large community-based sample of 645 children affected by parental HIV (Mage = 10.67 years, ranging from 8 to 15 years old). The three-level growth curve model revealed that higher peer victimization was associated with lower emotional regulation, which in turn was related to lower cortisol at awakening and more blunted diurnal slopes in girls, but not in boys. The findings highlight the protective effect of emotional regulation in relation to HPA axis activity in victimized children, particularly in girls.

"Dry mouth" and "Flammer" syndromes-neglected risks in adolescents and new concepts by predictive, preventive and personalised approach

Background

"Dry mouth" syndrome (chronic hyposalivation) can be caused by a number of pathophysiological conditions such as acute and chronic stress exposure, abnormal body weight (both too high and too low ones), eating disorders (such as anorexia nervosa), metabolic syndrome(s), Sjögren's and Sicca syndromes, drugs and head/neck radiotherapy application. In turn, the chronic hyposalivation as a suboptimal health condition significantly reduces quality of life, may indicate a systemic dehydration, provokes and contributes to a number of pathologies such as a strongly compromised protection of the oral cavity, chronic infections and inflammatory processes, periodontitis, voice and digestive disorders. Consequently, "dry mouth" syndrome might be extremely useful as an indicator for an in-depth diagnostics of both-co-existing and snowballing health-threating conditions. However, predictive diagnostics, targeted prevention and personalisation of treatments are evidently underdeveloped for individuals at high risk suffering from the "dry mouth" syndrome.

Working hypothesis and methodology

In the current study, we have hypothesised that individuals demonstrating "Flammer syndrome" (FS) phenotype may suffer from the "dry mouth" syndrome more frequently, due to disturbed microcirculation, psychological factors (obsessional personality/perfectionism), and diminished feeling of thirst with consequently insufficient daily liquid intake potentially resulting in the systemic dehydration with individually pronounced level of severity. If confirmed, FS phenotyping linked to the chronic hyposalivation might be predictive for individuals at risk identified by innovative screening programmes. To verify the working hypothesis, healthy individuals (negative control group) versus individuals with evident hyposalivation as well as patients diagnosed with periodontitis (positive control group) observed and treated at the dental clinic were investigated. The degree to which an individual is affected by hyposalivation was determined by the Bother xerostomia Index utilising a questionnaire of 10 issue-specific items and monitoring of a typically matt roof of the mouth in dental practice. An extent to which individuals included in the study are the carriers of the FS phenotype was estimated by the specialised 15-item questionnaire.

Results and conclusions

For both-the target group (hyposalivation) and positive control group (periodontitis)-FS phenotype was demonstrated to be more specific compared to the disease-free (negative control) group. Moreover, self-reports provided by interviewed adolescents of the target group frequently recorded remarkable discomfort related to "dry mouth" syndrome, acute and chronic otorhinolaryngological infections and even delayed wound healing. Further, interviewed adolescents do worry about the symptoms which might be indicative for potential diseases; they are also amazed that too little attention is currently paid to the issue by caregivers. In conclusion, FS questionnaire linked to the "dry mouth" syndrome is strongly recommended for application in primary healthcare. Consequently, targeted preventive measures can be triggered early in life. For example, traditional, complementary and alternative medicine demonstrates positive therapeutic effects in individuals suffering from xerostomia. For in-depth diagnostics, epi/genetic regulations involved into pathophysiologic mechanisms of hyposalivation in FS-affected individuals should be thoroughly investigated at molecular level. Identified biomarker panels might be of great clinical utility for predictive diagnostics and patient stratification that, further, would sufficiently improve personalised care to the patient.

The Role of the Lateral Hypothalamus in Violent Intraspecific Aggression-The Glucocorticoid Deficit Hypothesis

This review argues for a central role of the lateral hypothalamus in those deviant forms of aggression, which result from chronic glucocorticoid deficiency. Currently, this nucleus is considered a key region of the mechanisms that control predatory aggression. However, recent findings demonstrate that it is strongly activated by aggression in subjects with a chronically downregulated hypothalamus-pituitary-adrenocortical (HPA) axis; moreover, this activation is causally involved in the emergence of violent aggression. The review has two parts. In the first part, we review human findings demonstrating that under certain conditions, strong stressors downregulate the HPA-axis on the long run, and that the resulting glucocorticoid deficiency is associated with violent aggression including aggressive delinquency and aggression-related psychopathologies. The second part addresses neural mechanisms in animals. We show that the experimental downregulation of HPA-axis function elicits violent aggression in rodents, and the activation of the brain circuitry that originally subserves predatory aggression accompanies this change. The lateral hypothalamus is not only an integral part of this circuitry, but can elicit deviant and violent forms of aggression. Finally, we formulate a hypothesis on the pathway that connects unfavorable social conditions to violent aggression via the neural circuitry that includes the lateral hypothalamus.

Annual Research Review: The persistent and pervasive impact of being bullied in childhood and adolescence: implications for policy and practice

BACKGROUND

We have known for some time that being bullied was associated with children's and adolescents' adjustment difficulties and well-being. In recent years, we have come to recognise that the impact of childhood bullying victimisation on the development of mental health problems is more complex. This paper aims to review the evidence for an independent contribution of childhood bullying victimisation to the development of poor outcomes throughout the life span, including mental, physical and socioeconomic outcomes, and discuss the implications for policy and practice.

FINDINGS

Existing research indicates that (a) being bullied in childhood is associated with distress and symptoms of mental health problems. This large body of evidence supports actions aimed at reducing the occurrence of bullying behaviours; (b) the consequences of childhood bullying victimisation can persist up to midlife and, in addition to mental health, can impact physical and socioeconomic outcomes. These new findings indicate that interventions should also focus on supporting victims of bullying and helping them build resilience; (c) research has identified some factors that predispose children to be targeted by bullying behaviours. These studies suggest that public health interventions could aim at preventing children from becoming the target of bullying behaviours from an early age.

CONCLUSIONS

It is a truism to emphasise that further work is needed to understand why and how young people's aspirations are often cut short by this all too common adverse social experience. In parallel, we must develop effective strategies to tackle this form of abuse and its consequences for the victims. Addressing bullying in childhood could not only reduce children's and adolescents' mental health symptoms but also prevent psychiatric and socioeconomic difficulties up to adulthood and reduce considerable costs for society.

Bullying as a Stressor in Mid-Adolescent Girls and Boys-Associations with Perceived Stress, Recurrent Pain, and Salivary Cortisol

Bullying involves repeated exposure to negative actions while also invoking a power asymmetry between the involved parties. From a stress perspective, being bullied can be seen as a severe and chronic stressor, and an everyday social-evaluative threat, coupled with a shortage of effective social resources for dealing with this particular stressor. The aim of this study was to investigate whether exposure to bullying among mid-adolescent girls and boys is associated with subjective and objective stress-related outcomes in terms of perceived stress, recurrent pain, and salivary cortisol. The data came from the School Stress and Support Study (TriSSS) including students in grades 8-9 in two schools in Stockholm, Sweden, in 2010 (study sample n = 392; cortisol subsample n = 198). Bullying was self-reported and measured by multiple items. The statistical analyses included binary logistic and linear (OLS) regression. Being bullied was associated with greater perceived stress and an increased risk of recurrent pain, among both boys and girls. Also, bullied students had lower cortisol output (AUC_G) and lower cortisol awakening response (CAR_G) as compared to those who were not bullied. Gender-stratified analyses demonstrated that these associations were statistically significant for boys but not for girls. In conclusion, this study demonstrated that being bullied was related to both subjective and objective stress markers among mid-adolescent girls and boys, pointing to the necessity of continuously working against bullying.

Bullying victimisation and psychosis: The interdependence and independence of risk trajectories

A number of studies have noted an association between being the victim of bullying and psychotic symptoms. We offer an overview of the topic, focusing especially on a developmental perspective. We highlight the results of the latest studies on psychosis across the continuum and its relationship with bullying. Then we summarise the three main explanatory models investigated: developmental, biological and cognitive. We recommend that bullying in psychosis requires careful study of the developmental trajectories involved, and that research should now focus on how personal, social and biological factors interact.

LEARNING OBJECTIVES

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Developmental psychoneuroendocrine and psychoneuroimmune pathways from childhood adversity to disease

Childhood adversity has been repeatedly and robustly linked to physical and mental illness across the lifespan. Yet, the biological pathways through which this occurs remain unclear. Functioning of the inflammatory arm of the immune system and the hypothalamic-pituitary-adrenal (HPA)-axis are both hypothesized pathways through which childhood adversity leads to disease. This review provides a novel developmental framework for examining the role of adversity type and timing in inflammatory and HPA-axis functioning. In particular, we identify elements of childhood adversity that are salient to the developing organism: physical threat, disrupted caregiving, and unpredictable environmental conditions. We propose that existing, well-characterized animal models may be useful in differentiating the effects of these adversity elements and review both the animal and human literature that supports these ideas. To support these hypotheses, we also provide a detailed description of the development and structure of both the HPA-axis and the inflammatory arm of the immune system, as well as recent methodological advances in their measurement. Recommendations for future basic, developmental, translational, and clinical research are discussed.

Children's diurnal cortisol responses to negative events at school and home

This study examined the within-and between-person associations between daily negative events - peer problems, academic problems and interparental conflict - and diurnal cortisol in school-age children. Salivary cortisol levels were assessed four times per day (at wakeup, 30min later, just before dinner and at bedtime) on eight days in 47 youths ages 8-13 years old (60% female; M age=11.28, SD=1.50). The relative contributions of within- and between-person variances in each stressor were estimated in models predicting same-day diurnal cortisol slope, same-day bedtime cortisol, and next morning wakeup cortisol. Children who reported more peer problems on average showed flatter slopes of cortisol decline from wakeup to bedtime. However, children secreted more cortisol at wakeup following days when they had reported more peer or academic problems than usual. Interparental conflict was not significantly associated with diurnal cortisol. Findings from this study extend our understanding of short-term cortisol responses to naturally occurring problems in daily life, and help to differentiate these daily processes from the cumulative effects of chronic stress.

Is HPA axis reactivity in childhood gender-specific? A systematic review

BACKGROUND

In adults, hypothalamus-pituitary-adrenal (HPA) axis activity shows sexual dimorphism, and this is thought to be a mechanism underlying sex-specific disease incidence. Evidence is scarce on whether these sex differences are also present in childhood. In a meta-analysis, we recently found that basal (non-stimulated) cortisol in saliva and free cortisol in 24-h urine follow sex-specific patterns. We explored whether these findings could be extended with sex differences in HPA axis reactivity.

METHODS

From inception to January 2016, PubMed and EMBASE.com were searched for studies that assessed HPA axis reactivity in healthy girls and boys aged ≤18 years. Articles were systematically assessed and reported in the categories: (1) diurnal rhythm, (2) cortisol awakening response (CAR), (3) protocolled social stress tests similar or equal to the Trier Social Stress Test for children (TSST-C), (4) pharmacological (ACTH and CRH) stress tests, and (5) miscellaneous stress tests.

RESULTS

Two independent assessors selected 109 out of 6158 records for full-text screening, of which 81 studies (with a total of 14,591 subjects) were included. Studies showed that girls had a tendency towards a more variable diurnal rhythm (12 out of 29 studies), a higher CAR (8 out of 18 studies), and a stronger cortisol response to social stress tests (9 out of 21 studies). We found no evidence for sex differences in cortisol response after a pharmacological challenge or to miscellaneous stress tests.

DISCUSSION

Sex differences in HPA axis reactivity appear to be present in childhood, although evidence is not unequivocal. For a better evaluation of sex differences in HPA axis reactivity, standardization of protocols and reports of stress tests is warranted.

Responses to Interpersonal Stress: Normative Changes Across Childhood and the Impact of Peer Victimization

This research examined the development of stress responses across second to sixth grades and whether exposure to peer victimization alters stress response trajectories. Youth (338 girls; 298 boys; Mage  = 7.97 years, SD = .37) reported on stress responses; teachers and youth reported on peer victimization. Latent growth curve modeling revealed an increase in effortful engagement responses and a decrease in disengagement and involuntary engagement responses during this period. Peer victimization disrupted these normative trajectories, resulting in less effortful engagement and more effortful disengagement and involuntary stress responses in early adolescence. These findings suggest that early peer victimization sensitizes youth to stress by interfering with the development of effective coping and fostering maladaptive stress responses.

Environmental influence of problematic social relationships on adolescents' daily cortisol secretion: a monozygotic twin-difference study

BACKGROUND

This study investigated the potential environmental effects of peer victimization and the quality of relationships with parents and friends on diurnal cortisol secretion in mid-adolescence.

METHOD

This study used the monozygotic (MZ) twin-difference design to control for genetic effects and thus estimate the unique environmental influences on diurnal cortisol. Participants were 136 MZ twin pairs (74 female pairs) for whom cortisol was assessed four times per day over four collection days grouped in a 2-week period in grade 8 (mean age = 14.07 years). Participants also provided self-reports of peer victimization from grade 4 to grade 8 and of the relationship quality with the mother, father and best friend in grade 8.

RESULTS

The expected pattern of diurnal cortisol secretion was observed, with high levels at awakening followed by an increase 30 min later and a progressive decrease subsequently. Controlling for a host of confounders, only within-twin pair differences in peer victimization and a problematic relationship with the mother were significantly linked to twin differences in diurnal cortisol secretion. Specifically, whereas a more problematic mother-child relationship was associated with morning cortisol secretion, peer victimization was linked to cortisol secretion later in the day (diurnal slope).

CONCLUSIONS

Controlling for genetic influences and other confounders, stressful relationships with peers and the mother exert unique and time-specific environmental influences on the pattern of diurnal cortisol secretion in mid-adolescence.

Gender-specific differences in hypothalamus-pituitary-adrenal axis activity during childhood: a systematic review and meta-analysis

BACKGROUND

Gender-specific differences in hypothalamus-pituitary-adrenal (HPA) axis activity have been postulated to emerge during puberty. We conducted a systematic review and meta-analysis to test the hypothesis that gender-specific differences in HPA axis activity are already present in childhood.

METHODS

From inception to January 2016, PubMed and EMBASE.com were searched for studies that assessed non-stimulated cortisol in serum or saliva or cortisol in 24-h urine in healthy males and females aged ≤18 years. Studies that conform with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement were reported. Standardized mean differences (95% CIs) were calculated and analyzed using fixed-effect meta-analysis stratified for age: <8 years (prepubertal) and 8-18 years (peri-/postpubertal). For comparison, we ran the same analyses using random-effects models.

RESULTS

Two independent assessors selected 413 out of 6158 records (7%) for full-text screening, of which 79 articles were included. Of these, 58 (with data on 16,551 subjects) were included in the meta-analysis. Gender differences in cortisol metabolism differed per age group. Boys aged <8 years had 0.18 (0.06; 0.30) nmol/L higher serum and 0.21 (0.05; 0.37) nmol/L higher salivary cortisol levels, while between 8 and 18 years, boys had 0.34 (0.28; 0.40) nmol/L lower serum and 0.42 (0.38; 0.47) nmol/L lower salivary cortisol levels. In 24-h urine, cortisol was consistently higher in boys, being 0.34 (0.05; 0.64) and 0.32 (0.17; 0.47) μg/24 h higher in the <8- and 8-18-year groups, respectively. However, gender-differences in serum cortisol <8 years and between 8 and 18 years were absent when using random-effects models.

CONCLUSIONS

Gender differences in cortisol metabolism are already present in childhood, with higher salivary cortisol in boys aged <8 years compared to girls. This pattern was reversed after the age of 8 years. In contrast, the gender-specific difference in cortisol production as assessed through 24-h urine did not change with age. Although differences were small, and analyses of gender differences in serum cortisol were inconclusive, they might contribute to gender-specific origins of health and disease.

Rumination about Social Stress Mediates the Association between Peer Victimization and Depressive Symptoms during Middle Childhood

Although prior research has established a link between exposure to peer victimization and depressive symptoms, relatively little is known about the processes underlying this association. This study examined whether maladaptive responses to a novel social stressor - specifically, lower levels of problem solving or higher levels of rumination - mediate this association. Data were gathered from 130 children (64 boys, 66 girls; M age = 9.46, SD = .33) who participated in a laboratory social stressor task with an unfamiliar peer. Results indicated that prior exposure to peer victimization in the school context was associated with ruminative responses to the novel stressor, which mediated the association between victimization and depressive symptoms. These results indicate that ruminative responses to social stress outside of the victimization context may serve as one process explaining the association between victimization and heightened depressive symptoms.

Children and Adolescents and Digital Media

Today's children and adolescents are immersed in both traditional and new forms of digital media. Research on traditional media, such as television, has identified health concerns and negative outcomes that correlate with the duration and content of viewing. Over the past decade, the use of digital media, including interactive and social media, has grown, and research evidence suggests that these newer media offer both benefits and risks to the health of children and teenagers. Evidence-based benefits identified from the use of digital and social media include early learning, exposure to new ideas and knowledge, increased opportunities for social contact and support, and new opportunities to access health promotion messages and information. Risks of such media include negative health effects on sleep, attention, and learning; a higher incidence of obesity and depression; exposure to inaccurate, inappropriate, or unsafe content and contacts; and compromised privacy and confidentiality. This technical report reviews the literature regarding these opportunities and risks, framed around clinical questions, for children from birth to adulthood. To promote health and wellness in children and adolescents, it is important to maintain adequate physical activity, healthy nutrition, good sleep hygiene, and a nurturing social environment. A healthy Family Media Use Plan (www.healthychildren.org/MediaUsePlan) that is individualized for a specific child, teenager, or family can identify an appropriate balance between screen time/online time and other activities, set boundaries for accessing content, guide displays of personal information, encourage age-appropriate critical thinking and digital literacy, and support open family communication and implementation of consistent rules about media use.

Stress contagion in the classroom? The link between classroom teacher burnout and morning cortisol in elementary school students

OBJECTIVE

The purpose of this study was to explore the link between classroom teachers' burnout levels and students' physiological stress response. Drawing from a stress-contagion framework, we expected higher levels of teacher burnout to be related to elevated cortisol levels in elementary school students (N = 406, 50% female, Mean age = 11.26, SD = .89).

METHOD

Classroom teacher burnout was assessed with the Maslach Burnout Inventory modified for teachers. Salivary cortisol was collected as an indicator of students' hypothalamic-pituitary-adrenal (HPA) functioning. We collected salivary cortisol in children at 9 a.m., 11:30 a.m., and 2 p.m. in the classroom setting.

RESULTS

Using Multilevel Modeling, we found that children's morning cortisol levels significantly varied between classrooms (10% variability). Higher levels of classroom teacher burnout significantly predicted the variability in morning cortisol. Teacher burnout reduced the unexplained variability in cortisol at the classroom level to 4.6%.

CONCLUSION

This is the first study to show that teachers' occupational stress is linked to students' physiological stress regulation. We discuss the present findings in the context of potential stress contagion in the classroom, considering empirical and practical relevance.

Evidence of a unique and common genetic etiology between the CAR and the remaining part of the diurnal cycle: A study of 14 year-old twins

INTRODUCTION

By and large, studies have reported moderate contributions of genetic factors to cortisol secreted in the early morning and even smaller estimates later in the day. In contrast, the cortisol awakening response (CAR) has shown much stronger heritability estimates, which prompted the hypothesis that the etiology of cortisol secretion may vary according to the time of day. A direct test of this possibility has, however, not yet been performed.

OBJECTIVE

To describe the specific and common etiology of the CAR, awakening level and cortisol change from morning to evening in an age-homogenous sample of twin adolescents.

METHODS

A total of 592 participants of the Québec Newborn Twin Study, a population-based 1995-1998 cohort of families with twins in Canada, have collected saliva at awakening, 30 min later, at the end of afternoon and in the evening over four collection days.

RESULTS

Multivariate Cholesky models showed both specific and common sources of variance between the CAR, awakening and cortisol diurnal change. The CAR had the strongest heritability estimates, which, for the most part, did not overlap with the other indicators. Conversely, similar magnitudes of genetic and environmental contributions were detected at awakening and for diurnal change, which partially overlapped.

CONCLUSION

Our study unraveled differences between the latent etiologies of the CAR and the rest of the diurnal cycle, which may contribute to identify regulatory genes and environments and detangle how these indicators each relate to physical and mental health.

Understanding the Correlates of Face-to-Face and Cyberbullying Victimization Among U.S. Adolescents: A Social-Ecological Analysis

Using a national sample of 7,533 U.S. adolescents in grades 6-10, this study compares the social-ecological correlates of face-to-face and cyberbullying victimization. Results indicate that younger age, male sex, hours spent on social media, family socioeconomic status (SES; individual context), parental monitoring (family context), positive feelings about school, and perceived peer support in school (school context) were negatively associated with both forms of victimization. European American race, Hispanic/Latino race (individual), and family satisfaction (family context) were all significantly associated with less face-to-face victimization only, and school pressure (school context) was significantly associated with more face-to-face bullying. Peer groups accepted by parents (family context) were related to less cyberbullying victimization, and calling/texting friends were related to more cyberbullying victimization. Research and practice implications are discussed.

Relationship Between Peer Victimization and Posttraumatic Stress Among Primary School Children

Peer victimization is a common stressor experienced by children. Although peer victimization has been studied extensively, few studies have examined the potential link between peer victimization and posttraumatic stress disorder (PTSD), and no studies of which we are aware have examined this link among children in primary school. The paucity of studies examining the link between PTSD and peer victimization in primary school is surprising because peer victimization occurs more frequently and is more likely to be physical among 7- and 8-year-old children. This study assessed the relationship between peer victimization and PTSD in a sample of 358 elementary school children (ages 6-11 years). Results indicated that peer victimization accounted for 14.1% of PTSD symptom severity among boys and 10.1% among girls. Additionally, we found gender differences in the types of peer victimization that were most associated with PTSD symptom severity (d = 0.38). The long-term developmental consequences that may be associated with peer victimization-linked PTSD symptomatology are discussed.

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

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