The PedBE clock accurately estimates DNA methylation age in pediatric buccal cells.

The development of biological markers of aging has primarily focused on adult samples. Epigenetic clocks are a promising tool for measuring biological age that show impressive accuracy across most tissues and age ranges. In adults, deviations from the DNA methylation (DNAm) age prediction are correlated with several age-related phenotypes, such as mortality and frailty. In children, however, fewer such associations have been made, possibly because DNAm changes are more dynamic in pediatric populations as compared to adults. To address this gap, we aimed to develop a highly accurate, noninvasive, biological measure of age specific to pediatric samples using buccal epithelial cell DNAm. We gathered 1,721 genome-wide DNAm profiles from 11 different cohorts of typically developing individuals aged 0 to 20 y old. Elastic net penalized regression was used to select 94 CpG sites from a training dataset (n = 1,032), with performance assessed in a separate test dataset (n = 689). DNAm at these 94 CpG sites was highly predictive of age in the test cohort (median absolute error = 0.35 y). The Pediatric-Buccal-Epigenetic (PedBE) clock was characterized in additional cohorts, showcasing the accuracy in longitudinal data, the performance in nonbuccal tissues and adult age ranges, and the association with obstetric outcomes. The PedBE tool for measuring biological age in children might help in understanding the environmental and contextual factors that shape the DNA methylome during child development, and how it, in turn, might relate to child health and disease.

Rumination and Moderators of Multifinality: Predicting Internalizing Symptoms and Alcohol Use During Adolescence.

Rumination, a perseverative cognitive process that involves repetitively and passively focusing on negative emotions, is a transdiagnostic risk factor for the development of psychopathology. Although rumination has been linked to various forms of psychopathology including depression, anxiety, and alcohol misuse, little is known about the conditions that lead to multifinality. Here, we test putative moderators (Nolen-Hoeksema & Watkins, 2011) of the association between rumination and subsequent internalizing symptoms and frequency of alcohol use during adolescence. Participants included 388 youth (52% girls; 90% Caucasian) in a longitudinal birth cohort study who completed questionnaires in Grades 9 and 11. Brooding, a maladaptive form of rumination measured in Grade 9, was associated with greater internalizing symptoms in Grade 11 and greater perceived peer rejection in Grade 9 amplified this association. Brooding was also associated with greater frequency of alcohol use among adolescents who reported having more friends who use alcohol. Gender differences were also examined. Findings provide support for some of the predictions regarding moderators of multifinality made by Nolen-Hoeksema and Watkins. Implications of understanding divergent trajectories in the prevention of psychopathology are discussed.

Neuroendocrine coupling across adolescence and the longitudinal influence of early life stress.

Drawing on conceptual models illustrating the advantages of a multisystemic, interactive, developmental approach to understanding development, the present study examines the covariation of stress and sex hormones across the adolescent transition and the effect of early life stress (ELS) on neuroendocrine coupling to gain insight into atypical development. Morning levels of cortisol, testosterone, and dehydroepiandrosterone (DHEA) were assessed at ages 11, 13, and 15; ELS was assessed during the infancy and preschool periods. Hierarchical linear modeling revealed that cortisol-DHEA coupling patterns progressed to tight, positive coupling across adolescence. Cortisol-testosterone coupling was positive at age 11 but became more negative at ages 13 and 15. Exposure to ELS resulted in more adultlike neuroendocrine coupling patterns earlier in life than non-exposed youth; however the effect of ELS on cortisol-testosterone coupling was unique to girls. Results illustrate trajectories of neuroendocrine coupling that may be unique to adolescence. Moderation by ELS suggests that early stress exposure may prompt earlier adultlike neuroendocrine coupling, particularly within girls, which may contribute to early pubertal development.

Adolescent internalizing symptoms and negative life events: the sensitizing effects of earlier life stress and cortisol.

Although adolescence is marked by increased negative life events and internalizing problems, few studies investigate this association as an ongoing longitudinal process. Moreover, while there are considerable individual differences in the degree to which these phenomena are linked, little is known about the origins of these differences. The present study examines early life stress (ELS) exposure and early-adolescent longitudinal afternoon cortisol level as predictors of the covariation between internalizing symptoms and negative life events across high school. ELS was assessed by maternal report during infancy, and the measure of cortisol was derived from assessments at ages 11, 13, and 15 years. Life events and internalizing symptoms were assessed at ages 15, 17, and 18 years. A two-level hierarchical linear model revealed that ELS and cortisol were independent predictors of the covariation of internalizing symptoms and negative life events. Compared to those with lower levels of ELS, ELS-exposed adolescents displayed tighter covariation between internalizing symptoms and negative life events. Adolescents with lower longitudinal afternoon cortisol displayed tighter covariation between negative life events and internalizing symptoms, while those with higher cortisol demonstrated weaker covariation, partially due to increased levels of internalizing symptoms when faced with fewer negative life events.

The symphonic structure of childhood stress reactivity: patterns of sympathetic, parasympathetic, and adrenocortical responses to psychological challenge.

Despite widespread recognition that the physiological systems underlying stress reactivity are well coordinated at a neurobiological level, surprisingly little empirical attention has been given to delineating precisely how the systems actually interact with one another when confronted with stress. We examined cross-system response proclivities in anticipation of and following standardized laboratory challenges in 664 4- to 14-year-olds from four independent studies. In each study, measures of stress reactivity within both the locus coeruleus-norepinephrine system (i.e., the sympathetic and parasympathetic branches of the autonomic nervous system) and the corticotrophin releasing hormone system (i.e., the hypothalamic-pituitary-adrenal axis) were collected. Latent profile analyses revealed six distinctive patterns that recurred across the samples: moderate reactivity (average cross-system activation; 52%-80% of children across samples), parasympathetic-specific reactivity (2%-36%), anticipatory arousal (4%-9%), multisystem reactivity (7%-14%), hypothalamic-pituitary-adrenal axis specific reactivity (6%-7%), and underarousal (0%-2%). Groups meaningfully differed in socioeconomic status, family adversity, and age. Results highlight the sample-level reliability of children's neuroendocrine responses to stress and suggest important cross-system regularities that are linked to development and prior experiences and may have implications for subsequent physical and mental morbidity.

Epigenetic vestiges of early developmental adversity: childhood stress exposure and DNA methylation in adolescence.

Fifteen-year-old adolescents (N = 109) in a longitudinal study of child development were recruited to examine differences in DNA methylation in relation to parent reports of adversity during the adolescents' infancy and preschool periods. Microarray technology applied to 28,000 cytosine-guanine dinucleotide sites within DNA derived from buccal epithelial cells showed differential methylation among adolescents whose parents reported high levels of stress during their children's early lives. Maternal stressors in infancy and paternal stressors in the preschool years were most strongly predictive of differential methylation, and the patterning of such epigenetic marks varied by children's gender. To the authors' knowledge, this is the first report of prospective associations between adversities in early childhood and the epigenetic conformation of adolescents' genomic DNA.

Longitudinal stability and developmental properties of salivary cortisol levels and circadian rhythms from childhood to adolescence.

This study aimed to (1) identify a stable, trait-like component to cortisol and its circadian rhythm, and (2) investigate individual differences in developmental trajectories of HPA-axis maturation. Multiple salivary cortisol samples were collected longitudinally across four assessments from age 9 (3rd grade) through age 15 (9th grade) in a community sample of children (N = 357). Sophisticated statistical models examined cortisol levels and its rhythm over time; effects of age, puberty and gender were primarily considered. In addition to situation-specific and stable short-term or epoch-specific cortisol components, there is a stable, trait-like component of cortisol levels and circadian rhythm across multiple years covering the transition from childhood into adolescence. Youth had higher cortisol and flatter circadian rhythms as they got older and more physically developed. Girls had higher cortisol, stronger circadian rhythms, and greater developmental influences across adolescence. Distinguishing a stable, trait-like component of cortisol level and its circadian rhythm provides the empirical foundation for investigating putative mechanisms underlying individual differences in HPA functioning. The findings also provide important descriptive information about maturational processes influencing HPA-axis development.

Early family context and development of adolescent ruminative style: moderation by temperament.

We know very little about the development of rumination, the tendency to passively brood about negative feelings. Because rumination is a risk factor for many forms of psychopathology, especially depression, such knowledge could prove important for preventing negative mental health outcomes in youth. This study examined developmental origins of rumination in a longitudinal sample (N=337; 51% girls) studied in preschool (ages 3½ and 4½ years) and early adolescence (ages 13 and 15 years). Results indicated that family context and child temperament, assessed during the preschool period, were risk factors for a ruminative style in adolescence. Specifically, early family contexts characterised by over-controlling parenting and a family style of negative-submissive expressivity predicted higher levels of later rumination. These associations were moderated by children's temperamental characteristics of negative affect and effortful control. Further, the interaction of these temperament factors exerted an additional influence on later rumination. Implications for prevention and intervention efforts are discussed.

Behavioral and emotional symptoms of post-institutionalized children in middle childhood.

BACKGROUND: Experience in institutional/orphanage care has been linked to increased mental health problems. Research suggests that children adopted from institutions experience specific difficulties related to inattention/overactivity. Evidence of internalizing and conduct problems relative to non-adopted peers has been found in early childhood and early adolescence, but problems may not differ from other adopted children. This study clarifies the understanding of behavioral and emotional symptoms of post-institutionalized (PI) children during middle childhood. METHODS: Eight- to eleven-year-old PI children (n=68) and two comparison groups, children internationally adopted from foster care (n=74) and non-adopted children (n=76), and their parents completed the MacArthur Health and Behavior Questionnaire related to attention-deficit/hyperactivity disorder (ADHD), externalizing, and internalizing symptoms. Group means for symptom level and number of children with symptoms above clinical cutoffs were compared. RESULTS: PI children displayed an increased level of ADHD symptoms per parent report. PI child and parent report indicated a higher number of PI children above clinical ADHD cutoff. Both groups of internationally adopted (IA) children had higher levels of externalizing symptoms relative to non-adopted children, with parent report indicating higher numbers of IA children above the externalizing clinical threshold. Informants differed in their report of internalizing symptoms. Parents indicated that both IA groups displayed increased internalizing symptom levels and greater numbers above clinical threshold; however, children reported this to be true only for the PI group. CONCLUSIONS: PI children differ from non-adopted peers across symptom domains in middle childhood. Whether these concerns were more broadly associated with international adoption rather than institutional care depended on symptom domain and informant. An understanding of this variability may be beneficial for treatment and intervention.

Biological sensitivity to context moderates the effects of the early teacher-child relationship on the development of mental health by adolescence.

The moderating effects of biological sensitivity to context (physiological and behavioral stress reactivity) on the association between the early teacher-child relationship and the development of adolescent mental health problems were examined in a community sample of 96 children. Grade 1 measures of biological sensitivity to context included physiological (i.e., slope of mean arterial pressure across a 20- to 30-min stress protocol) and behavioral (i.e., temperamental inhibition/disinhibition) markers. Grade 1 measures of the teacher-child relationship included positive (i.e., closeness) and negative (i.e., conflict) qualities. Mental health symptoms were assessed at Grades 1 and 7. Results of a multiple regression analysis indicated substantial association of the teacher-child relationship with the development of adolescent mental health symptoms, especially for more reactive children. In addition to teacher-child relationship main effects, all four Reactivity x Teacher-Child Relationship interaction terms were statistically significant when controlling for Grade 1 symptom severity, suggesting that both physiological and behavioral reactivity moderate the association of both adverse and supportive aspects of the teacher-child relationship with Grade 7 symptom severity over and above Grade 1 severity. There were important differences, depending on which stress reactivity measure was considered. The importance of these findings for recent theoretical arguments regarding biological sensitivity to context and differential susceptibility is discussed.

Influence of early life stress on later hypothalamic-pituitary-adrenal axis functioning and its covariation with mental health symptoms: a study of the allostatic process from childhood into adolescence.

The hypothalamic-pituitary-adrenal (HPA) axis is a primary mechanism in the allostatic process through which early life stress (ELS) contributes to disease. Studies of the influence of ELS on children's HPA axis functioning have yielded inconsistent findings. To address this issue, the present study considers multiple types of ELS (maternal depression, paternal depression, and family expressed anger), mental health symptoms, and two components of HPA functioning (traitlike and epoch-specific activity) in a long-term prospective community study of 357 children. ELS was assessed during the infancy and preschool periods; mental health symptoms and cortisol were assessed at child ages 9, 11, 13, and 15 years. A three-level hierarchical linear model addressed questions regarding the influences of ELS on HPA functioning and its covariation with mental health symptoms. ELS influenced traitlike cortisol level and slope, with both hyper- and hypoarousal evident depending on type of ELS. Further, type(s) of ELS influenced covariation of epoch-specific HPA functioning and mental health symptoms, with a tighter coupling of HPA alterations with symptom severity among children exposed previously to ELS. Results highlight the importance of examining multiple types of ELS and dynamic HPA functioning in order to capture the allostatic process unfolding across the transition into adolescence.

Sex Differences in the Relationship Between Childhood Self-Regulation and Adolescent Adiposity.

OBJECTIVE: Research suggests that higher childhood self-regulation (CSR) predicts lower adiposity in adolescence. However, it is unclear whether this relationship differs by sex or by baseline weight status. Thus, this study investigated these questions in a longitudinal, community-based cohort. METHODS: The cohort included 221 girls and 214 boys. At age 9, CSR was assessed via parent/teacher reports of effortful control, and childhood BMI z scores (BMIz) were calculated from staff measurements. Late-adolescent waist-to-height ratio was based on staff measurements at age 18. RESULTS: CSR has a small inverse correlation with concurrent childhood BMIz in girls, but not in boys. Prospectively, however, CSR has a small inverse association with late-adolescent weight-to-height ratio in both sexes, after adjusting for childhood BMIz and other childhood predictors. This prospective association is marginally stronger for girls with higher (vs. lower) childhood BMIz. CONCLUSIONS: CSR inversely predicts changes in adiposity across adolescence in both sexes, with some evidence that this association is stronger for girls with higher (vs. lower) childhood adiposity. However, this inverse association between CSR and adiposity may emerge earlier in girls. Future research should examine the causal status of CSR and its relationship to behaviors (e.g., diet).

Gender differences in emotional reactivity of depressed and at-risk preschoolers: implications for gender specific manifestations of preschool depression.

We investigated whether differences in positive and negative emotional reactivity could be found in depressed preschoolers and preschoolers at risk for later internalizing symptoms relative to nondepressed/low risk comparison groups. Observational measures of emotional reactivity, used to derive a score of the balance between anger and sadness, were obtained and analyzed in independent samples. One study utilized cross-sectional data from preschoolers (M age = 4.6 years) with a current depressive syndrome and two nondepressed comparison groups. The other study utilized longitudinal data that assessed emotional reactivity at preschool age (M age = 4.5 years) and later mental health symptoms during the transition to primary school, allowing a retrospective determination of risk. Depressed and at-risk boys displayed more anger than sadness in contrast to girls in the same groups and in contrast to no disorder/low-risk controls. This finding was detected in depressed and "at risk for internalizing" boys who were not comorbid for externalizing problems.

Identification of early child and family risk factors for aggressive victim status in first grade.

This prospective investigation sought to discriminate children who were both aggressive towards and victimized by peers in the first grade, from those who were only aggressive, only victimized, or neither (i.e., socially adjusted), using early child and family risk factors. Two hundred thirty-eight children, their mothers, and teachers participated in a longitudinal study since birth. All three aggressor/victim subgroups showed greater temperamental dysregulation than the socially adjusted children, but only aggressive victims had significantly poorer social perception skills. Aggressive victims were distinguished from aggressors by greater exposure to maternal depression and from victims by lower levels of early inhibition, but they shared the experiences of negative family emotional expressiveness with aggressors and greater mother-child negativity with victims. The identification of early risk factors is crucial to prevention and early intervention efforts that have the potential to attenuate the long term emotional, social, and academic problems associated with aggressive victim status.

Exploring risk factors for the emergence of children's mental health problems.

CONTEXT: Exploratory studies that generate testable models of how risk factors for childhood mental health problems work together over time are critical for developing effective prevention and treatment strategies. OBJECTIVE: To build models addressing the following 2 questions: (1) How early can we identify children at risk for mental health problems in third grade? (2) How do the risk factors work together over time? DESIGN AND PARTICIPANTS: We assessed a Wisconsin community sample 8 times, beginning during pregnancy. Three hundred seventy-nine families completed multi-informant reports (mothers, teachers, and children) of children's mental health symptoms in third grade. MAIN OUTCOME MEASURES: Symptom severity and directionality (externalizing vs internalizing). RESULTS: The hypothesis was generated that family socioeconomic status (SES) defined different pathways to symptom severity. In low/middle SES families, children were at risk if their mothers were distressed during the infancy period, which was then associated with more generalized maternal and child distress and dysregulation during the preschool period. In high SES families, the picture was more complex, beginning with parental histories of depression and family psychopathology, which then led to greater family stress in the infancy period and maternal and child distress and dysregulation during the preschool period. For all children, social and academic impairment during the school transition was an important mediator. Two pathways to later symptom directionality consisted of one beginning with child sex and the other with child temperament. CONCLUSIONS: Most risk factors predicted symptom severity and not directionality. The risk factors for internalizing and externalizing problems may be much the same, and the same preventive interventions might be effective for both classes of problems. Furthermore, at-risk children from high SES families might be identifiable as early as infancy, whereas those from lower SES families may be identifiable only as preschoolers.

Early adversity, elevated stress physiology, accelerated sexual maturation, and poor health in females.

Evolutionary-minded developmentalists studying predictive-adaptive-response processes linking childhood adversity with accelerated female reproductive development and health scientists investigating the developmental origins of health and disease (DOoHaD) may be tapping the same process, whereby longer-term health costs are traded off for increased probability of reproducing before dying via a process of accelerated reproductive maturation. Using data from 73 females, we test the following propositions using path analysis: (a) greater exposure to prenatal stress predicts greater maternal depression and negative parenting in infancy, (b) which predicts elevated basal cortisol at 4.5 years, (c) which predicts accelerated adrenarcheal development, (d) which predicts more physical and mental health problems at age 18. Results prove generally consistent with these propositions, including a direct link from cortisol to mental health problems. DOoHaD investigators should consider including early sexual maturation as a core component linking early adversity and stress physiology with poor health later in life in females.

Longitudinal associations between diurnal cortisol slope and alcohol use across adolescence: a seven-year prospective study.

A large body of research has linked hypothalamic-pituitary-adrenal (HPA) axis function and alcohol consumption, including work suggesting that flatter diurnal cortisol slopes are associated with greater alcohol use. A lack of longitudinal studies and a focus on adult and alcoholic populations leaves unclear whether such associations are also present in younger, non-clinical populations and whether flatter diurnal slopes are a consequence of or preexisting risk factor for alcohol use; however, theory suggests such associations may be mutually reinforcing. In a longitudinal, community sample of 200 (55% female) adolescents, the current study demonstrates that flatter diurnal cortisol slope at age 11 predicts higher levels of alcohol use from ages 15-18, and that heavier alcohol use in turn predicts further flattening of diurnal cortisol rhythm at age 18.5. This is the first study to demonstrate a longitudinal chain of associations between diurnal cortisol slope and alcohol use. Findings support contemporary theoretical models of the neurobiological processes underlying alcohol use and can inform future research on risk factors for and consequences of underage drinking.

Preschool externalizing behavior predicts gender-specific variation in adolescent neural structure.

Dysfunction in the prefrontal cortex, amygdala, and hippocampus is believed to underlie the development of much psychopathology. However, to date only limited longitudinal data relate early behavior with neural structure later in life. Our objective was to examine the relationship of early life externalizing behavior with adolescent brain structure. We report here the first longitudinal study linking externalizing behavior during preschool to brain structure during adolescence. We examined the relationship of preschool externalizing behavior with amygdala, hippocampus, and prefrontal cortex volumes at age 15 years in a community sample of 76 adolescents followed longitudinally since their mothers' pregnancy. A significant gender by externalizing behavior interaction revealed that males-but not females-with greater early childhood externalizing behavior had smaller amygdala volumes at adolescence (t = 2.33, p = .023). No significant results were found for the hippocampus or the prefrontal cortex. Greater early externalizing behavior also related to smaller volume of a cluster including the angular gyrus and tempoparietal junction across genders. Results were not attributable to the impact of preschool anxiety, preschool maternal stress, school-age internalizing or externalizing behaviors, or adolescent substance use. These findings demonstrate a novel, gender-specific relationship between early-childhood externalizing behavior and adolescent amygdala volume, as well as a cross-gender result for the angular gyrus and tempoparietal junction.

The confluence of mental, physical, social, and academic difficulties in middle childhood. II: developing the Macarthur health and Behavior Questionnaire.

OBJECTIVES: (1) To evaluate the psychometric properties of the MacArthur Health and Behavior Questionnaire (HBQ) in two studies of 4- to 8-year-old children and (2) to explore the empirical and theoretical implications of HBQ-based study findings. METHOD: Samples of children were recruited from (1) mental health clinics (n = 53) and community schools (n = 67) for a case-control study in three research sites and (2) a Wisconsin-based community cohort study of families and work, comprising children with high levels of internalizing and/or externalizing behavior problems and asymptomatic children (N = 122). Combinations of mothers, fathers, and teachers completed the HBQ at one or two time points in four geographically and culturally distinctive settings. RESULTS: Assessment of HBQ reliability showed high test-retest stability and cross-informant agreement. The instrument discriminated strongly and significantly among symptom groups (i.e., high internalizing, high externalizing, high both, and low both) and showed moderate to large effect sizes for between-group differences. Substantial covariance was also found among the HBQ mental, physical, social, and academic problem subscales. CONCLUSIONS: The HBQ is a reliable and valid parent- and teacher-report instrument for assessing multiple dimensions of health and dysfunction in middle childhood and for identifying children on whom more intensive diagnostic procedures may be warranted. Confluences among the four health dimensions suggest phenomenological and perhaps etiological commonalities among traditionally partitioned childhood difficulties and suggest possible artificiality in the conventional distinction between pediatric and child psychiatric morbidities.

Associations of child insomnia, sleep movement, and their persistence with mental health symptoms in childhood and adolescence.

STUDY OBJECTIVES: To examine the patterns of insomnia and sleep-related movement from ages 4.5 to 9 years, their concurrent associations with mental health symptoms in childhood, and the longitudinal associations of sleep-problem persistence with mental health symptoms at ages 9 and 18 years. DESIGN: A 14-year prospective follow-up study. Assessments included maternal report on the Children's Sleep Habits Questionnaire at ages 4.5 and 9, and child mental health symptoms via maternal report at age 4.5, multi-informant (child, teacher, mother) report at age 9, and adolescent report at age 18. SETTING: Community. PARTICIPANTS: A total of 396 children (51% female). INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Sleep problems were more common at age 4.5 than 9; symptoms of insomnia and abnormal sleep movement both had persistence rates of 9-10%. At age 4.5, insomnia was associated with hostile-aggressive and hyperactive-distractible behavior, but there were no significant associations for sleep movement. At age 9, both insomnia and sleep movement were associated with symptoms of depression, externalizing, and attention deficit hyperactivity disorder (ADHD). Insomnia persistence was associated with symptoms of depression, externalizing, and ADHD at age 9 and anxiety and externalizing at age 18; sleep- movement persistence was associated with externalizing and ADHD at age 9, and ADHD at age 18. The age 18 persistence effects for insomnia and anxiety and for sleep movement and ADHD were significant when controlling for earlier mental health. CONCLUSIONS: Childhood insomnia and sleep movement are common and associated with mental health symptoms. Their persistence from middle to late childhood predicts associations with specific types of mental health symptoms at age 18.