Childhood Social Disadvantage and Pubertal Timing: A National Birth Cohort From Australia

Long-term Neighborhood Poverty Effects on Internalizing Symptoms in Adolescents: Mediated Through Allostatic Load and Pubertal Timing

PURPOSE

The long-term effect of neighborhood poverty on internalizing symptoms in adolescents and the biological mechanisms underlying this association remain unclear. We defined neighborhood poverty at the village level in two dimensions: intensity (i.e., poverty rate) and duration. This study investigated how the poverty rate and duration of exposure to neighborhood poverty interact to predict internalizing symptoms in adolescents through biological mechanisms (i.e., allostatic load and early pubertal timing).

METHODS

A total of 418 adolescents (50.2% girls; 11-14 years old; mean age = 12.57 years) living in rural China participated in two waves of data collection. Path analysis was conducted to examine the mediating role of allostatic load and pubertal timing in the relationship between the duration of exposure to neighborhood poverty and internalizing symptoms. Moreover, the interactive effect between the poverty rate and duration of neighborhood poverty on the allostatic load was tested.

RESULTS

The positive association between the duration of exposure to neighborhood poverty and internalizing symptoms of adolescents was explained by elevated allostatic load and early pubertal timing after adjusting for gender, age, prior family socioeconomic states and internalizing symptoms. The duration in neighborhood poverty was a stronger predictor of allostatic load for adolescents living in high poverty rate neighborhoods than for those living in low poverty rate neighborhoods.

DISCUSSION

Neighborhood poverty gets "under the skin" through biological pathways and affects internalizing symptoms among adolescents. The findings highlight the importance of considering different dimensions of neighborhood poverty (e.g., intensity and duration) on adolescents' health.

Distinct Constellations of Common Risk Factors Differentially Relate to Executive-Function Ability in Children

Executive functioning (EF) has been shown to relate to academic achievement and well-being. Independent bodies of work have aimed to understand what environmental or personal attributes influence EF ability. However, most research has not considered how constellations of risk factors create distinct patterns of influence on EF ability. The current study tested a sample of children aged 9 to 10 years from the United States (N = 10,323, 48.06% female, Mage = 9.9 years, age range = 8.9-11.08 years) using a latent profile analysis (LPA) to detect subgroups that varied in their combinations of various risk factors. Six distinct groups of risk factors for children emerged, which in turn related to different average EF abilities. We found that family socioeconomic measures related to a subgroup having above- or below-average EF ability, but we also found an effect on EF across different risk factors. These results inform our understanding of individual variations in EF ability and highlight the idea that EF interventions should consider risk holistically.

Skin-deep Resilience and Early Adolescence: Neighborhood Disadvantage, Executive Functioning, and Pubertal Development in Minority Youth

Skin-deep resilience, in which youth overcome adversity and achieve success in psychological and academic domains but at a cost to their physiological well-being, has been documented in late adolescence and adulthood. However, its potential to emerge at earlier developmental stages is unknown. To address this gap, secondary data analyses were executed using waves 1 and 2 of the Adolescent Brain Cognitive Development study (n = 7712; ages 9-10 years at baseline [mean: 9.92; SD = 0.63]; 47.1% female; 66.1% White, 13.4% Black, and 20.6% Hispanic). The results indicated high levels of executive functioning were associated with improved psychological and behavioral outcomes at one-year follow-up. However, for racial and ethnic minority (i.e., Black or Hispanic) youth from disadvantaged neighborhoods, high levels of executive functioning were also associated with accelerated pubertal development. No significant interaction was observed among White youth. The findings suggest the skin-deep resilience pattern may be evident in early adolescence.

Pubertal timing, sex hormone levels, and associations between early life adversity and accelerated development amongst 11-year-old children of parents with schizophrenia or bipolar disorder and controls: The Danish high risk and Resilience study via 11

Background

Children of parents with severe mental illness have several known risk factors for altered pubertal timing. Pubertal timing is important for children's physical and emotional development. We aimed to examine pubertal timing and associations between pubertal timing, early life adversity and child problem behavior including psychiatric diagnoses among children of parents with schizophrenia or bipolar disorder and controls.

Methods

Self-reported Tanner stage (mean age 11.9, range 10.87-12.67), sex hormone levels, home environment, placement out of home, and problem behavior including psychiatric diagnoses of children at familial high-risk (FHR) of schizophrenia (FHR-SZ), bipolar disorder (FHR-BP) and population-based controls (PBC) were assessed.

Results

A total of 465 children participated in the study (Tanner assessment N = 417, sex hormones N = 293). Assessed with self-reported Tanner, no difference in pubertal timing was found between groups (p = 0.09). Hormone levels did not differ between groups except for inhibin B (mean (SD) = 55.86 (29.13) pg/mL for FHR-SZ girls vs 84.98 (47.98) pg/mL) for PBC girls (p < 0.001)) and for follicle stimulating hormone (FSH) (mean (SD) = 5.82 (1.45) U/L for FHR-BP girls vs 4.54 (1.68) U/L for PBC girls (p < 0.001)). FHR children who were placed out of home (17 children, 3.8% of participants) had higher Tanner stages than those living at home (p < 0.001). Timing was not associated with level of problem behavior or psychiatric diagnoses.

Conclusions

FHR children did not differ from controls in pubertal timing. Early life adversity assessed as placement out of home may be associated with accelerated pubertal timing among children of parents with schizophrenia or bipolar disorder.

How pubertal timing and self-regulation predict adolescent sexual activity in resource-poor environments

Studies found support for a link between pubertal timing and self-regulation in low-resource environments. This link could potentially explain a link between pubertal timing and early risk behavior. This study builds on this body of research by examining the mediated effect of pubertal timing on sexual activity through self-regulation in 728 adolescents and their families in a group with poor resources and a group with adequate resources. Income-to-Needs (ITN) was measured at age 7.5 to establish two groups (low-ITN and Medium/High-ITN). Pubertal timing was measured at age 10.5, self-regulation was assessed at age 14 and operationalized with effortful control, and sexual activity was assessed at age 16. Structural equation modeling was employed to test the hypothesized model in both groups. The link between pubertal timing and sexual activity mediated by effortful control was only significant in the low-ITN group. Specifically, more advanced pubertal maturity was associated with lower levels of adolescents' effortful control, which in turn was associated with more sexual activity at age 16. Findings were partially replicated with a drug use index replacing sexual activity. This study shows a different operating link from pubertal timing to effortful control and subsequent risk behavior in resource-poor environments. Implications are discussed.

The rise and fall of SES gradients in heights around the world

We use data from a large sample of low- and middle-income countries to study the association (or "gradient") between child height and maternal education. We show that the gap in height between high- and low-SES children is small at birth, rises throughout childhood, and declines in adolescence as girls and boys go through puberty. This inverted U-shaped pattern is consistent with a degree of catch-up in linear height among children of low- relative to high-SES families, in partial contrast to the argument that height deficits cannot be overcome after the early years of life. This finding appears to be explained by the association between SES and the timing of puberty and therefore of the adolescent growth spurt: low-SES children start their adolescent growth spurt later and stop growing at later ages as well.

Social Safety Theory: Conceptual foundation, underlying mechanisms, and future directions

Classic theories of stress and health are largely based on assumptions regarding how different psychosocial stressors influence biological processes that, in turn, affect human health and behavior. Although theoretically rich, this work has yielded little consensus and led to numerous conceptual, measurement, and reproducibility issues. Social Safety Theory aims to address these issues by using the primary goal and regulatory logic of the human brain and immune system as the basis for specifying the social-environmental situations to which these systems should respond most strongly to maximize reproductive success and survival. This analysis gave rise to the integrated, multi-level formulation described herein, which transforms thinking about stress biology and provides a biologically based, evolutionary account for how and why experiences of social safety and social threat are strongly related to health, well-being, aging, and longevity. In doing so, the theory advances a testable framework for investigating the biopsychosocial roots of health disparities as well as how health-relevant biopsychosocial processes crystalize over time and how perceptions of the social environment interact with childhood microbial environment, birth cohort, culture, air pollution, genetics, sleep, diet, personality, and self-harm to affect health. The theory also highlights several interventions for reducing social threat and promoting resilience.

Neighborhood Racial and Economic Privilege and Timing of Pubertal Onset in Girls

PURPOSE

Early puberty is associated with adverse health outcomes over the life course, and Black and Hispanic girls experience puberty earlier than girls of other racial/ethnic backgrounds. Neighborhood racial and economic privilege may contribute to these disparities by conferring differential exposure to mechanisms (e.g., stress, obesity, endocrine disruptors) underlying early puberty. We examined associations between neighborhood privilege, measured by the Index of Concentration at the Extremes (ICE), and age at pubic hair onset (pubarche) and breast development onset (thelarche) in a large multiethnic cohort.

METHODS

A cohort of 46,299 girls born 2005-2011 at Kaiser Permanente Northern California medical facilities were followed until 2021. Pubertal development was assessed routinely by pediatricians using the Sexual Maturity Rating scale. ICE quintiles for race/ethnicity, income, and income + race/ethnicity were calculated using American Community Survey 2010 5-year estimates and linked to census tract at birth. We fit multilevel Weibull regression models accommodating left, right, and interval censoring for all analyses.

RESULTS

ICE measures were monotonically associated with pubertal onset, with the strongest associations observed for ICE-race/ethnicity. Adjusting for maternal education, age at delivery, and parity, girls from the least versus most privileged ICE-race/ethnicity quintiles were at increased risk for earlier pubarche (hazard ratio: 1.30, 95% confidence interval: 1.21, 1.38) and thelarche (hazard ratio: 1.45, 95% confidence interval: 1.36, 1.54). These associations remained significant after adjusting for girls' race/ethnicity and childhood body mass index. Additionally, adjustment for ICE partially attenuated Black-White and Hispanic-White disparities in pubertal onset.

DISCUSSION

Neighborhood privilege may contribute to pubertal timing and related disparities.

Gender differentials in the timing and prognostic factors of pubarche in Nigeria

Paucity of data exists on the timing of puberty, particularly the pubarche, in developing countries, which has hitherto limited the knowledge of the timing of pubarche, and assistance offered by physicians to anxious young people in Nigeria. Factors associated with the timings of puberty and pubarche are not well documented in Nigeria. We hypothesized that the timing of pubarche in Nigeria differs by geographical regions and other characteristics. We assessed the timing of pubarche among adolescents and young adults in Nigeria and identified prognostic factors of the timing by obtaining information on youths' sexual and reproductive developments in a population survey among in-school and out-of-school youths aged 15 to 24 years in Nigeria. A total of 1174 boys and 1004 girls provided valid information on pubarche. Results of time-to-event analysis of the data showed that mean age at pubarche among males aged 15 to 19 years and 20 to 24 years was 13.5 (SD = 1.63 years) and 14.2 (SD = 2.18 years) (respectively) compared with 13.0 (SD = 1.57 years) and 13.5 (SD = 2.06 years) among females of the same age. Median time to pubarche was 14 (Interquartile range (IQR) = 3) years and 13 (IQR = 3) years among the males and females, respectively. Cumulatively, 37% of the males had attained pubarche by age 13 years versus 53% among females, 57% vs 72% at age 14, and 73% vs 81% at age 15. The likelihood of pubarche among males was delayed by 5% compared with females (Time Ratio (TR) = 1.05: 95% CI = 1.03-1.05). Every additional one-year in the ages of both males and females increases the risk of pubarche by 1%. Similar to the females, males residents in Northeast (aTR = 1.14, 95% CI: 1.07-1.21), in the Northwest (aTR = 1.20, 95% CI: 1.13-1.27) and in the Southwest (aTR = 1.18, 95% CI: 1.11-1.26) had delayed pubarche than males from the South East. Yoruba males had delayed pubarche than Ibo males (aTR = 1.06, 95% CI: 1.01-1.12). Age at pubarche among adolescents and young adults in Nigeria differed among males and females with earlier onset among females. Pubarche timing varied mainly by ethnicity, region, and location of residence. Our findings will aid medical practitioners in providing appropriate advice and support on pubarche-related issues among adolescents in Nigeria as it could help douse pubarche anxiousness in relation to request for medical assistance.

Early menarche and adult major depressive disorder among Japanese women: The role of childhood traumatic experience and socioeconomic conditions in young adulthood

Aim

The aim of this study is to examine the long-term impact of early menarche with adult depression, and to assess whether this association was explained by childhood traumatic experience and socioeconomic condition in early adulthood.

Methods

The data were derived from World Mental Health Survey Japan Second, a cross-sectional survey conducted among Japanese community residents between 2013 and 2015. We used the data of female respondents aged 20-75 years (N = 1171). Hazard ratio (HR) of the onset of major depression up to 40 years was calculated for an early-menarche group and a non-early-menarche group, respectively. Kaplan-Meier curve and log-rank statistics were used to examine the difference in failure. Cox proportional hazard models were administered for the association of major depression with early-menarche and early-life psychosocial factors.

Results

Risk for major depressive disorders were three to four times higher in an early-menarche group, and the differences in survival functions were significant (p < 0.001). HR of early menarche was 2.79 (95% CI = 1.29-6.02), and was slightly changed when childhood traumatic experience and socioeconomic conditions in young adulthood were added in the model (HR = 2.88, 95% CI = 1.30-6.38; HR = 3.19, 95% CI = 1.41-7.21).

Conclusion

Early menarche was significantly associated with increased risk for depression by the age of 40 years. Childhood trauma and socioeconomic hardship in early adulthood did not account for the association. Both physical and psychosocial risk factors in early life need to be addressed for preventing women's depression.

Does pubertal stage mediate the association between family environment and structure and function of the amygdala-mPFC circuit? A replication study of the longitudinal ABCD cohort

Psychosocial acceleration theory suggests that early stress accelerates pubertal development. Using half of the baseline Adolescent Brain and Cognitive Development (ABCD) cohort, Thijssen et al. (2020) provide support that accelerated puberty following stressful family environments may promote neurodevelopment. Here, we replicate and extend those analyses using 1) data from the second half of the ABCD sample (n = 3300 +, ages 9-10), and 2) longitudinal imaging data from the original sample (n = 1800 +, ages 11-12). A family environment latent variable was created and related to anterior cingulate cortex (ACC) thickness, area, white matter fractional anisotropy, amygdala volume, and cingulo-opercular network (CON)-amygdala resting-state functional connectivity. Results from the independent sample replicate the mediating effects of family environment through pubertal stage on amygdala-CON functional connectivity. Sex-stratified analyses show indirect effects via pubertal stage in girls; boys show evidence for direct associations. Analyses using wave 2 imaging data or wave 2-wave 1 difference scores from the originally-analyzed sample replicate the resting-state indirect effects. The current paper replicates the mediating role for puberty in the association between family environment and neurodevelopment. As both direct and indirect associations were found, puberty may be one of multiple mechanisms driving accelerated neurodevelopment following environmental stress.

Association of early menarche with elevated BMI, lower body height and relative leg length among 14- to 16-year-old post-menarcheal girls from a Maya community in Yucatan, Mexico

Human body segments have different timing and tempo of growth. Early menarche (EM) as an indicator of early reproductive maturity results in a shortened height and leg length. Relatively larger trunk may increase risk for more body fat deposit and higher body mass index (BMI) due to the allometry of total body fat with body proportions. The objective of the study was to assess the association of EM with BMI, absolute body size [height, sitting height (SH), subischial leg length (SLL)] and relative body dimensions [sitting height to subischial leg length ratio (SHSLLR), relative subischial leg length (RSLL)] among 14- to 16-year-old post-menarcheal girls from a rural Maya community in Quintana Roo, Yucatan, Mexico. In a cross-sectional study, post-menarcheal girls (n=51) aged 14 to 16 years had EM (n=22) (<12 years of age) and not early menarche (NEM, n=29). Anthropometric measurements of height, weight, and SH were recorded. Derived variables were BMI, height and BMI-for-age z-scores, SLL, SHSLLR, and RSLL. Mean value of age at menarche (AM) was 13 years (EM 11 years, NEM 14 years). Mean values of height (EM 159 cm, NEM 164 cm), BMI (EM 20 kg/m2, NEM 19 kg/m2), sitting height (EM 81 cm, NEM 78 cm), SLL (EM 79 cm, NEM 85 cm), SHSLLR (EM 102.93%, NEM 92.03%), and RSLL (EM 49%, NEM 52%) were different (p<0.05) in the two groups. BMI showed significant negative correlation with AM (Pearson’s r=-0.29, p<0.04). Linear regression models adjusted for age showed that EM had different interrelationships (p<0.05) with body dimensions: positive with BMI, SH, SHSLLR, and negative with height, SLL, and RSLL. Earlier AM was associated with higher BMI, SH, SHSLLR and lower SLL, RSLL, explaining lower body height and leg length among the participant EM girls. In the light of life history theory, EM results in a growth trade-off, short stature and larger trunk relative to leg length that might enhance risk for body fat gain.

Socioeconomic Status Is Related to Pubertal Development in a German Cohort

INTRODUCTION

Current health literature suggests that there has been a decline in the age of pubertal onset and that pubertal onset/duration of puberty may, besides weight status, be influenced by socioeconomic context.

OBJECTIVE

The goal of this study was to determine whether pubertal onset/duration and puberty-triggering hormones luteinizing hormone (LH) and follicle-stimulating hormone (FSH) vary according to socioeconomic status (SES). Moreover, we aimed to propose cutoff values of serum LH and FSH for predicting gonadarche in boys.

METHODS

2,657 apparently healthy children and adolescents between 5.5 and 18 years from the area of Leipzig were recruited from the LIFE Child study. Age at pubertal onset/end of puberty was given in 738/573 children, respectively. Anthropometric parameters of puberty, blood measurements of LH and FSH, and questionnaires assessing SES were evaluated.

RESULTS

Lower SES was associated with earlier thelarche and longer duration of puberty in overweight/obese girls, whereas age of menarche was not affected. In boys with low SES, a trend versus earlier puberty onset can be seen. Lower SES was significantly associated with boys' age at mutation. No significant differences in boys' and girls' serum levels of LH and FSH during puberty according to SES were observed. Serum LH levels of 0.56 IU/L and serum FSH levels of 1.74 IU/L showed the best prediction of gonadarche in boys.

CONCLUSION

Puberty onset/duration and boys' age at mutation is affected by SES. The proposed cutoff levels for serum LH and FSH could provide a serological tool to determine gonadarche in boys.

The Effect of Neighborhood-level Resources on Children's Physical Development: Trajectories of Body Mass Index and Pubertal Development and the Influence of Child Biological Sex

Growing research substantiates the role of neighborhood disadvantage in contributing to early pubertal maturation and higher body mass index; however, previous studies in this area have design limitations. Specifically, many studies have been cross-sectional, have used singular indicators of neighborhood disadvantage (e.g., poverty), and have provided mixed findings about the role of biological sex. The present study addresses these gaps by examining how neighborhood resources (spanning educational, health/environmental, and social/economic domains) predict trajectories of pubertal maturation and body mass index using longitudinal multi-wave data. Furthermore, multigroup analyses assessed how these associations may differ by child biological sex. Participants in this study (n = 505; 54% male) were assessed every 3 years at age 9 (M = 9.17, SD = 0.39), age 12 (M = 12.63, SD = 0.43), and age 15 (M = 15.23, SD = 0.37). Approximately 12% of the sample identified as Hispanic, and 11% as non-White. Using multigroup latent growth analyses, the study examined how neighborhood resources predicted trajectories of pubertal maturation and body mass index using multi-wave data across middle childhood through mid-adolescence. The findings suggested that greater neighborhood resources were cross-sectionally associated with lower pubertal development and predicted slower trajectories across time. Although all girls in the study eventually progressed through pubertal development, girls in lower resourced neighborhoods experienced a much earlier onset of puberty. Additionally, greater neighborhood resources predicted lower BMI both cross sectionally and longitudinally. Specifically, higher resourced neighborhoods were protective against obesity risk for both boys and girls across mid-childhood through mid-adolescence. In sum, the study highlights the role of broader neighborhood factors on early maturity risk for female children, and obesity risk for children regardless of biological sex.

Neighborhood disadvantage and longitudinal brain-predicted-age trajectory during adolescence

Neighborhood disadvantage has consistently been linked to alterations in brain structure; however, positive environmental (e.g., positive parenting) and psychological factors (e.g., temperament) may buffer these effects. We aimed to investigate associations between neighborhood disadvantage and deviations from typical neurodevelopmental trajectories during adolescence, and examine the moderating role of positive parenting and temperamental effortful control (EC). Using a large dataset (n = 1313), a normative model of brain morphology was established, which was then used to predict the age of youth from a longitudinal dataset (n = 166, three time-points at age 12, 16, and 19). Using linear mixed models, we investigated whether trajectories of the difference between brain-predicted-age and chronological age (brainAGE) were associated with neighborhood disadvantage, and whether positive parenting (positive behavior during a problem-solving task) and EC moderated these associations. We found that neighborhood disadvantage was associated with positive brainAGE during early adolescence and a deceleration (decreasing brainAGE) thereafter. EC moderated this association such that in disadvantaged adolescents, low EC was associated with delayed development (negative brainAGE) during late adolescence. Findings provide evidence for complex associations between environmental and psychological factors, and brain maturation. They suggest that neighborhood disadvantage may have long-term effects on neurodevelopment during adolescence, but high EC could buffer these effects.

Assessment of the median ages at sexual maturation stages of Brazilian schoolchildren according to overweight status and type of school over a 5-year period: 2007-2012/2013

OBJECTIVES

A secular trend of earlier puberty has been observed in girls, and, although more uncertain in boys, is associated with an increasing trend in the prevalence of overweight and obesity. We aimed to compare the median ages of sexual maturation stages in schoolchildren from a city in southern Brazil over a 5-year period, according to weight status and type of school.

METHODS

Two cross-sectional studies were performed in 2007 and 2012/2013, including 2215 and 1614 schoolchildren, respectively. Body mass index z-scores were calculated and categorized as either nonoverweight or overweight (including obesity). The type of school was categorized as either public or private. Sexual maturation was self-assessed according to the Tanner stages. Mann-Whitney and Kruskal-Wallis tests were performed to compare the median ages of sexual maturation stages.

RESULTS

The median age decreased for almost all stages over the 5-year period in both sexes. In boys, the decrease ranged from 0.3 to 1.0 years (stages 2, 3, 4, and 5 for genitalia, and stages 2 and 4 for pubic hair), and from 0.3 to 0.7 years (stages 2, 3, and 4 for breast, and stages 3, 4, and 5 for pubic hair). In 2012, overweight students had lower median ages for most stages compared to those in 2007, especially in girls. Differences by type of school were balanced across years.

CONCLUSIONS

The median age of Tanner's stages after 5 years was reduced in both sexes. In overweight girls, the reduction was more pronounced. The results by type of school were inconsistent.

Environmentally relevant perinatal exposure to DBP disturbs testicular development and puberty onset in male mice

Di-n-butyl phthalate (DBP) is considered as a potential modifier of puberty. However, different results indicate that DBP plays an accelerated, delayed, or neutral role in the initiation of puberty. Furthermore, whether the effect of DBP on puberty will disrupt the function of reproductive system in the adults is still ambiguous. Therefore, we aimed to investigate the effect of maternal exposure to DBP on the onset of puberty in male offspring mice and the subsequent changes in the development of reproductive system. Here, pregnant mice were treated with 0 (control), 50, 250, or 500 mg/kg/day DBP in 1 mL/kg corn oil administered daily by oral gavage from gestation day (GD) 12.5 to parturition. Compared with the control group, the 50 mg/kg/day DBP group accelerated puberty onset and testicular development were quite remarkable in male offspring mice during early puberty. Furthermore, in 22-day male offspring mice, 50 mg/kg/day DBP induced increased levels of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone in serum, and promoted the expression of steroidogenesis-related genes in the testes. Testicular Leydig cells (LCs) were isolated from the testes of 3-week-old mice and treated with 0 (control), 0.1, 1 mM monobutyl phthalate (MBP, the active metabolite of DBP) for 24 h. Consistent with the in vivo results, the expression of steroidogenesis-related genes and testosterone production were increased in LCs following exposure to 0.1 mM MBP. In adulthood, testes of the male offspring mice exposed to all doses of DBP exhibited adverse morphology compared with the control group. These results demonstrated that maternal exposure to 50 mg/kg/day DBP induced earlier puberty and precocious development of the testis, and eventually damaged the reproductive system in the later life.

Childhood Socioeconomic Status and Menarche: A Prospective Study

PURPOSE

The relationship between socioeconomic status (SES) and menarche has implications for understanding social level influences on early life development and adult disease, including breast cancer, but remains ill defined. We report here results from the Breast Cancer and the Environment Research Program, which permitted a longitudinal study of age at menarche in relationship to childhood SES in a diverse cohort of 1,069 girls across three urban areas of the United States.

METHODS

We assessed the association of SES index quintiles with age at pubertal onset with breast budding and subsequent tempo to the age at menarche between 2004 and 2015 using multiple-event Cox regression models to estimate hazard ratios and 95% confidence intervals.

RESULTS

In an unadjusted model, lower SES was predictive of both earlier pubertal onset and tempo and thus earlier age at menarche in trends across quintiles. After adjusting for the potentially mediating effects of body mass index, SES trends remained significant for both outcomes. After adjusting for both body mass index and race/ethnicity, the association with SES remained substantial for pubertal onset but was much diminished and nonsignificant for tempo and thus age at menarche.

CONCLUSIONS

These results suggest that a lower SES environment and social adversity affect the age at menarche primarily by hastening pubertal onset rather than by shortening tempo.

Environmental influences on the pace of brain development

Childhood socio-economic status (SES), a measure of the availability of material and social resources, is one of the strongest predictors of lifelong well-being. Here we review evidence that experiences associated with childhood SES affect not only the outcome but also the pace of brain development. We argue that higher childhood SES is associated with protracted structural brain development and a prolonged trajectory of functional network segregation, ultimately leading to more efficient cortical networks in adulthood. We hypothesize that greater exposure to chronic stress accelerates brain maturation, whereas greater access to novel positive experiences decelerates maturation. We discuss the impact of variation in the pace of brain development on plasticity and learning. We provide a generative theoretical framework to catalyse future basic science and translational research on environmental influences on brain development.

Associations Between Neighborhood Disadvantage, Resting-State Functional Connectivity, and Behavior in the Adolescent Brain Cognitive Development Study: The Moderating Role of Positive Family and School Environments

BACKGROUND

Neighborhood disadvantage has consistently been associated with mental health and cognitive function, in addition to alterations in brain function and connectivity. However, positive environmental influences may buffer these effects. The aim of this study was to examine the association between neighborhood disadvantage and resting-state functional connectivity (rsFC), the moderating role of positive parenting and school environment, and relationships between disadvantage-associated rsFC patterns and mental health and cognition.

METHODS

In this preregistered study, we tested this hypothesis in a large sample of 7618 children (aged 9-10 years) from the Adolescent Brain Cognitive Development (ABCD) study. Specifically, we analyzed the relationship between neighborhood disadvantage and system-level FC. We also tested whether positive family and school environmental factors and sex moderated effects. Finally, we investigated multivariate relationships between disadvantage-associated rsFC patterns and cognition and mental health.

RESULTS

Disadvantage was associated with widespread alterations in FC across both higher-order (e.g., default mode network and dorsal attention network) and sensorimotor functional systems, some of which were moderated by positive environments. Implicated connections showed multivariate associations with behavior, whereby disadvantage-associated rsFC was generally associated with worse cognition and mental health. Disadvantage-associated connections also predicted variation in cognitive scores using machine learning models.

CONCLUSIONS

Our findings shed light on potential mechanisms (i.e., alteration of neural circuitry) through which neighborhood disadvantage may affect youth cognition and mental well-being. This work highlights the importance of positive family and school environments in mitigating some of these effects.

Correspondence Between Perceived Pubertal Development and Hormone Levels in 9-10 Year-Olds From the Adolescent Brain Cognitive Development Study

Aim

To examine individual variability between perceived physical features and hormones of pubertal maturation in 9-10-year-old children as a function of sociodemographic characteristics.

Methods

Cross-sectional metrics of puberty were utilized from the baseline assessment of the Adolescent Brain Cognitive Development (ABCD) Study-a multi-site sample of 9-10 year-olds (n = 11,875)-and included perceived physical features via the pubertal development scale (PDS) and child salivary hormone levels (dehydroepiandrosterone and testosterone in all, and estradiol in females). Multi-level models examined the relationships among sociodemographic measures, physical features, and hormone levels. A group factor analysis (GFA) was implemented to extract latent variables of pubertal maturation that integrated both measures of perceived physical features and hormone levels.

Results

PDS summary scores indicated more males (70%) than females (31%) were prepubertal. Perceived physical features and hormone levels were significantly associated with child's weight status and income, such that more mature scores were observed among children that were overweight/obese or from households with low-income. Results from the GFA identified two latent factors that described individual differences in pubertal maturation among both females and males, with factor 1 driven by higher hormone levels, and factor 2 driven by perceived physical maturation. The correspondence between latent factor 1 scores (hormones) and latent factor 2 scores (perceived physical maturation) revealed synchronous and asynchronous relationships between hormones and concomitant physical features in this large young adolescent sample.

Conclusions

Sociodemographic measures were associated with both objective hormone and self-report physical measures of pubertal maturation in a large, diverse sample of 9-10 year-olds. The latent variables of pubertal maturation described a complex interplay between perceived physical changes and hormone levels that hallmark sexual maturation, which future studies can examine in relation to trajectories of brain maturation, risk/resilience to substance use, and other mental health outcomes.

Early Life Adversity and Pubertal Timing: Implications for Cardiometabolic Health

OBJECTIVE

To identify early life adversity (ELA) risk factors for earlier pubertal timing, itself a risk factor for poor cardiometabolic health, and to determine whether such ELA-related risk may be mediated by pre-pubertal body mass index (BMI).

METHODS

Subjects included 426 female participants in a prospective birth cohort study, the NICHD Study of Early Child Care and Youth Development. Survival analysis models were fit to examine ELA exposures, representing childhood socioeconomic status (SES), maternal sensitivity, mother-child attachment, and negative life events, along with child health indicators and covariates, in relation to pubertal timing outcomes, including age at menarche and ages at Tanner stage II for breast and pubic hair development.

RESULTS

Higher childhood SES emerged as an independent predictor of older age at menarche, showing each one standard deviation increase in childhood SES corresponded to a 1.3% increase in age at menarche (factor change = 1.013; 1.003-1.022; p < .01), but did not predict breast or pubic hair development (ps > .05). In mediation analyses, indirect (mediated) effects of mother-child attachment on the pubertal timing outcomes, via pre-pubertal BMI, were all statistically significant (ps < .05).

CONCLUSIONS

Higher childhood SES predicted directly, and secure (vs. insecure) mother-child attachment predicted indirectly (via pre-pubertal BMI), later pubertal timing, suggesting these factors may protect girls from earlier pubertal development. By extension, clinical implications are that intervention strategies designed to lessen ELA- and pre-pubertal obesity-related risk may be effective in remediating life course pathways linking ELA, accelerated pubertal development, and cardiometabolic risk.

The geroscience agenda: Toxic stress, hormetic stress, and the rate of aging

Geroscience offers a counterpoint to the challenged pursuit of curing diseases of aging, by focusing on slowing the biological aging process for extended healthspan earlier in life. Remarkable progress has led this field toward animal trials and the next challenge lies with translation to humans. There is an emerging number of small human trials that can take advantage of new models integrating behavioral and social factors. Understanding dynamic aging mechanisms, given the powerful social determinants of aging (Crimmins, 2020) and human variability and environmental contexts (Moffitt, 2020), will be critical. Behavioral and social factors are intrinsic to aging. Toxic stressors broadly defined can lead to stress-acceleration of aging, either directly impacting aging processes or by shaping poor behavioral health, and underlie the socioeconomic disparities of aging. In contrast, hormetic stressors, acute intermittent stressors of moderate intensity, can produce stress resilience, the ability for quick recovery and possibly rejuvenation of cells and tissues. Although health research usually examines static biomarkers, aging is reflected in dynamic ability to recover from challenges pointing to new interventions and targets for examining mechanisms. A fuller model incorporating stress resilience provides innovative biobehavioral interventions, both for bolstering response to challenges, such as COVID-19, and for improving healthspan.

Child-related and parental predictors for thelarche in a general population of girls: the PANIC study

BACKGROUND

Obesity has been associated with earlier thelarche, whereas other predictors for it remain unclear.

METHODS

We studied child-related and parental predictors for earlier thelarche in 195 girls aged 6-8 years followed up for 2 years. A physician evaluated breast development by inspection and palpation. Body fat percentage (BF%) was measured by dual-energy X-ray absorptiometry, diet by food records, and physical activity and sedentary time by body movement and heart rate monitors. Parental education, smoking, and alcohol consumption and household income were assessed by questionnaires. Gestational age, birth weight, and maternal prepregnancy BMI were obtained from hospital registers. Predictors for thelarche were examined using logistic regression analysis adjusted for age and follow-up time.

RESULTS

The incidence of thelarche during 2 years increased by 11% (OR 1.11, CI 1.06-1.17, p < 0.001) for 1 unit increase in baseline BF%. Girls with a smoking parent had a 2.64 (95% CI 1.21-5.77, p = 0.015) times higher incidence of thelarche than other girls. The associations of lower parental education and higher maternal prepregnancy BMI with the higher incidence of thelarche were largely explained by BF%. Other possible predictors were not associated with thelarche.

CONCLUSIONS

Higher BF% and exposure to tobacco smoke are independent predictors for earlier thelarche.

Association of Early-Life Adversity With Measures of Accelerated Biological Aging Among Children in China

IMPORTANCE

A growing body of literature suggests that exposure to early-life adversity (ELA) is associated with accelerated biological aging, offering 1 mechanism through which ELA may be associated with an increased risk for age-related disease. These investigations, however, have been predominantly cross-sectional and focused on adults and females.

OBJECTIVE

To evaluate associations of threat-related (ie, physical abuse) and deprivation-related (ie, emotional neglect) ELA exposure with cellular and reproductive strategy metrics of biological aging among boys and girls with specific genetic backgrounds around the period of pubertal onset.

DESIGN, SETTING, AND PARTICIPANTS

In this cohort study, 997 boys and girls in grade 1 to grade 3 from 3 large elementary schools were recruited from Bengbu, Anhui Province, China, and were followed up from March 21, 2016 (baseline; wave 1), for 4 consecutive years, through March 25, 2019.

MAIN OUTCOMES AND MEASURES

The outcome was accelerated biological aging in both cellular and reproductive strategy metrics: telomere attrition and age at thelarche (for girls) and testicular maturation (for boys). Multi-informant assessment of exposure to threat-related and deprivation-related ELA was done at baseline (wave 1) and 1-year follow-up (wave 2). The polygenic risk score (PRS) was computed based on 17 single-nucleotide variations for early pubertal timing.

RESULTS

Of the 997 participants (579 girls [58.1%]; mean [SD] age at baseline, 8.0 [0.8] years), 550 (55.2%) reported exposure to threat-related ELA and 443 (44.4%) reported exposure to deprivation-related ELA. Threat-related ELA was associated with onset of thelarche 2.6 months earlier and deprivation-related ELA with onset of thelarche 3.3 months earlier in exposed girls than in unexposed peers; these associations were observed only among girls with a low PRS. Among boys, a similar pattern was found. Threat-related ELA was associated with testicular volume of 4 mL or more 1.4 months earlier and deprivation-related ELA was associated with testicular volume of 4 mL or more 2.3 months earlier than in unexposed peers but only among those with a low PRS. Boys and girls with greater exposure to threats showed a significantly higher percentage of telomere length change during 1-year follow-up, but only among those with low PRS (boys: β = 1.50; 95% CI, 0.80-2.21; P < .001; girls: β = 2.40; 95% CI, 1.78-3.05; P < .001) and moderate PRS (boys: β = 1.09; 95% CI, 0.43-1.75; P = .001; and girls: β = 1.27; 95% CI, 0.77-1.77; P < .001). No associations of deprivation-related ELA with percentage of telomere length change were found.

CONCLUSIONS AND RELEVANCE

This study suggests that the accelerating association of ELA with biological aging might occur at an earlier age and in a genetic background-dependent and dimension-specific manner.

Connections Between Obesity and Puberty: Invited by Manuel Tena-Sempere, Cordoba

The relationship between obesity and puberty remains controversial. Whereas cross-sectional and longitudinal studies show a clear shift toward earlier puberty in obese girls, the trend in obese boys remains less obvious. Overweight boys mature earlier whereas obese boys mature later compared to healthy weight boys. Newer epidemiologic studies attempt to address these knowledge gaps. This review provides a detailed overview of the recent literature regarding secular trends in pubertal onset and tempo, and the connection with obesity. Additionally, this review summarizes potential mediators that permit obesity to promote early puberty. Other factors such as socioeconomic status, in utero exposures, nutritional, and even endocrine disrupting chemicals can cause perturbation of both metabolism and the endocrine axis that can ultimately have effects on pubertal development.

Adverse adolescence experiences, feeling lonely across life stages and loneliness in adulthood

Loneliness is a mental health issue emerging over the life course. This study examines the latent structure of adult loneliness in a non-Western society and its association with adverse adolescence experiences (AAEs) as well as feeling lonely during middle school, high school, and college. Method: A cohort sample living in Northern Taiwan (N = 2,289) was analyzed from adolescence to adulthood. The de Jong Gierveld Loneliness Scale operationalized loneliness by a three-cluster model to present the latent structure of loneliness: emotional, serious emotional, and severe emotional/social loners. AAEs (e.g., abuse, neglect, and dysfunctional family) were measured by seven items. Multivariate multinomial logistic regression models were used to explore the longitudinal effects of AAEs and feeling lonely reported during middle school, high school, and college on adult loneliness. Results: AAEs and feeling lonely during adolescence were significantly associated with serious emotional loneliness and severe emotional/social loneliness during adulthood, even after adjusting for the individual’s characteristics. Attendance at a 4-year college was associated with decreased odds of serious emotional loneliness and severe emotional/social loneliness. Conclusions: Adults with AAEs and feelings of loneliness over life stages are more likely to report loneliness in the emotional and social domains.

Biological aging in childhood and adolescence following experiences of threat and deprivation: A systematic review and meta-analysis

Life history theory argues that exposure to early life adversity (ELA) accelerates development, although existing evidence for this varies. We present a meta-analysis and systematic review testing the hypothesis that ELA involving threat (e.g., violence exposure) will be associated with accelerated biological aging across multiple metrics, whereas exposure to deprivation (e.g., neglect, institutional rearing) and low-socioeconomic status (SES) will not. We meta-analyze 54 studies (n = 116,010) examining associations of ELA with pubertal timing and cellular aging (telomere length and DNA methylation age), systematically review 25 studies (n = 3,253) examining ELA and neural markers of accelerated development (cortical thickness and amygdala-prefrontal cortex functional connectivity) and evaluate whether associations of ELA with biological aging vary according to the nature of adversity experienced. ELA overall was associated with accelerated pubertal timing (d = -0.10) and cellular aging (d = -0.21), but these associations varied by adversity type. Moderator analysis revealed that ELA characterized by threat was associated with accelerated pubertal development (d = -0.26) and accelerated cellular aging (d = -0.43), but deprivation and SES were unrelated to accelerated development. Systematic review revealed associations between ELA and accelerated cortical thinning, with threat-related ELA consistently associated with thinning in ventromedial prefrontal cortex, and deprivation and SES associated with thinning in frontoparietal, default, and visual networks. There was no consistent association of ELA with amygdala-PFC connectivity. These findings suggest specificity in the types of early environmental experiences associated with accelerated biological aging and highlight the importance of evaluating how accelerated aging contributes to health disparities and whether this process can be mitigated through early intervention. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Early Pubertal Timing Mediates the Association between Low Socioeconomic Status and Poor Attention and Executive Functioning in a Diverse Community Sample of Adolescents

Low socioeconomic status (SES) may be associated with earlier pubertal timing and impaired attention and executive function (EF) in youth; however, whether pubertal timing mediates the relation between SES and attention or executive functioning remains unclear. Structural equation models tested concurrent and prospective relations between SES, pubertal timing, and attention and executive functioning measures in a gender and racially diverse sample of adolescents (N = 281, 45.6% male, 50.5% White/Caucasian, 46.3% Black/African American, 3.2% Biracial/other, and 44.5% low SES; complete data were not available on some measures). Youth from low SES families experienced earlier pubertal timing, and this accelerated development was associated with worse performance on attention and executive functioning tasks, both concurrently and longitudinally. These findings highlight a pathway by which youth from low socioeconomic backgrounds may develop worse attention and executive functioning abilities during adolescence.

Early Puberty and Telomere Length in Preadolescent Girls and Mothers

OBJECTIVE

To test the association between early puberty and telomere length in preadolescent girls and mothers from a large representative sample of US females.

STUDY DESIGN

We analyzed data from 1194 preadolescent girls and 2421 mothers from the Fragile Families and Child Wellbeing Study. Participants were from a population-based birth cohort (1998-2000) born in large US cities. Telomere length was assessed by quantitative polymerase chain reaction from saliva samples provided by preadolescent girls and mothers of preadolescent youth. Mothers completed a questionnaire about their child's pubertal development to determine concurrent Tanner stages and provided self-reports of her own age at menarche. Linear regression models were used to estimate the association between pubertal development (status and timing) and telomere length.

RESULTS

Early pubertal timing but not pubertal status was associated with shorter telomere length in preadolescent girls (P < .01). Early age at menarche was associated with shorter telomere length in a sample of mothers of preadolescent youth (P < .05).

CONCLUSIONS

Results provide evidence for the association between early puberty and shorter telomeres evidenced by associations in both preadolescent girls and mothers. Future research should address the limitations of this study by using longitudinal measurements of pubertal development assessed through medical examinations and repeated assessments of telomere length to capture telomere attrition.

Disorders of Pubertal Onset

Evaluation of the child with abnormal pubertal development can be challenging for the primary care provider. Understanding the factors associated with timing of pubertal onset and the normal sequence of pubertal changes is useful in evaluation of children with puberty disorders. A thorough workup includes assessment of growth rate, Tanner staging, and rate of pubertal progression, in addition to an extensive history and physical examination to identify signs and symptoms of disorders associated with abnormal pubertal timing. Initial diagnostic studies will most often include a bone age, levels of gonadotropins, and levels of estradiol (for girls) or testosterone (for boys).

Earlier age at menarche as a transdiagnostic mechanism linking childhood trauma with multiple forms of psychopathology in adolescent girls

BACKGROUND

Although early life adversity (ELA) increases risk for psychopathology, mechanisms linking ELA with the onset of psychopathology remain poorly understood. Conceptual models have argued that ELA accelerates development. It is unknown whether all forms of ELA are associated with accelerated development or whether early maturation is a potential mechanism linking ELA with psychopathology. We examine whether two distinct dimensions of ELA - threat and deprivation - have differential associations with pubertal timing in girls, and evaluate whether accelerated pubertal timing is a mechanism linking ELA with the onset of adolescent psychopathology.

METHODS

Data were drawn from a large, nationally representative sample of 4937 adolescent girls. Multiple forms of ELA characterized by threat and deprivation were assessed along with age at menarche (AAM) and the onset of DSM-IV fear, distress, externalizing, and eating disorders.

RESULTS

Greater exposure to threat was associated with earlier AAM (B = -0.1, p = 0.001). Each 1-year increase in AAM was associated with reduced odds of fear, distress, and externalizing disorders post-menarche (ORs = 0.74-0.85). Earlier AAM significantly mediated the association between exposure to threat and post-menarche onset of distress (proportion mediated = 6.2%), fear (proportion mediated = 16.3%), and externalizing disorders (proportion mediated = 2.9%).

CONCLUSIONS

Accelerated pubertal development in girls may be one transdiagnostic pathway through which threat-related experiences confer risk for the adolescent onset of mental disorders. Early pubertal maturation is a marker that could be used in both medical and mental health settings to identify trauma-exposed youth that are at risk for developing a mental disorder during adolescence in order to better target early interventions.

Adverse Childhood Experiences and Early Pubertal Timing Among Girls: A Meta-Analysis

The association between adverse childhood experiences (ACEs) and pubertal timing has been a topic of enduring controversy. A systematic search of PubMed and Web of Science databases was undertaken to quantify the magnitude of total and specific forms of ACEs effects on early pubertal timing among girls. Our search identified 3280 records, of which 43 studies with 46 independent data sets met inclusion criteria. We estimated pooled effect sizes (Cohen’s ds) for the association between ACEs with early pubertal timing. Total ACEs was not associated with early pubertal timing. When we examined the specific types of ACEs, associations were small to medium for father absence (d = −0.40, 95% confidence interval [CI]: −0.63, −0.16) and small for sexual abuse (d = −0.13, CI: −0.17, −0.10) and family dysfunction (d = −0.08, CI: −0.11, −0.02). We identified considerable heterogeneity between estimates for almost all of the outcomes. ACEs exposure may affect female reproductive reproduction, particularly father absence, sexual abuse, and family dysfunction. We propose that future research in this area test a theoretical model linking adversity with earlier reproductive strategy, which includes early pubertal timing as a core component linking early adversity and stress physiology with poor health outcomes later in life in females.

Early life disadvantage, phenotypic programming, and health disparities

Much research finds that early life socioeconomic disadvantage predicts poorer health later in life, even among those whose conditions improve in adulthood. Although there are numerous factors that contribute to this association, recent research suggests that growing up in adverse socioecological environments may promote developmental patterns that facilitate pre-reproductive survival in harsh environments, but can also come at the cost of reduced longevity. Here, we review recent research demonstrating that early life exposure to low socioeconomic status can become embedded in the mechanisms that regulate (a) bodily inflammatory activity and (b) energy regulation in ways that contribute to poor health. This research offers new insights into ways that early life environments can get under one's skin to impact health and longevity.

Early menarche is associated with lower adult lung function: A longitudinal cohort study from the first to sixth decade of life

BACKGROUND AND OBJECTIVE

Early menarche is increasing in prevalence worldwide, prompting clinical and public health interest on its links with pulmonary function. We aimed to investigate the relationship between early menarche and lung function in middle age.

METHODS

The population-based Tasmanian Longitudinal Health Study (born 1961; n = 8583), was initiated in 1968. The 5th Decade follow-up data (mean age: 45 years) included age at menarche and complex lung function testing. The 6th Decade follow-up (age: 53 years) repeated spirometry and gas transfer factor. Multiple linear regression and mediation analyses were performed to determine the association between age at menarche and adult lung function and investigate biological pathways, including the proportion mediated by adult-attained height.

RESULTS

Girls reporting an early menarche (<12 years) were measured to be taller with greater lung function at age 7 years compared with those reporting menarche ≥12 years. By 45 years of age, they were shorter and had lower post-bronchodilator (BD) forced expiratory volume in 1 s (adjusted mean difference: -133 mL; 95% CI: -233, -33), forced vital capacity (-183 mL; 95% CI: -300, -65) and functional residual capacity (-168 mL; 95% CI: -315, -21). Magnitudes of spirometric deficits were similar at age 53 years. Forty percent of these total effects were mediated through adult-attained height.

CONCLUSION

Early menarche was associated with reduced adult lung function. This is the first study to investigate post-BD outcomes and quantify the partial role of adult height in this association.

More than a snapshot in time: pathways of disadvantage over childhood

Background

Disadvantage rarely manifests as a single event, but rather is the enduring context in which a child's development unfolds. We aimed to characterize patterns of stability and change in multiple aspects of disadvantage over the childhood period, in order to inform more precise and nuanced policy development.

Methods

Participants were from the Longitudinal Study of Australian Children birth cohort (n = 5107). Four lenses of disadvantage (sociodemographic, geographic environment, health conditions and risk factors), and a composite of these representing average exposure across all lenses, were assessed longitudinally from 0 to 9 years of age. Trajectory models identified groups of children with similar patterns of disadvantage over time for each of these lenses and for composite disadvantage. Concurrent validity of these trajectory groups was examined through associations with academic performance at 10-11 years.

Results

We found four distinct trajectories of children's exposure to composite disadvantage, which showed high levels of stability over time. In regard to the individual lenses of disadvantage, three exhibited notable change over time (the sociodemographic lens was the exception). Over a third of children (36.3%) were exposed to the 'most disadvantaged' trajectory in at least one lens. Trajectories of disadvantage were associated with academic performance, providing evidence of concurrent validity.

Conclusions

Children's overall level of composite disadvantage was stable over time, whereas geographic environments, health conditions and risk factors changed over time for some children. Measuring disadvantage as uni-dimensional, at a single time point, is likely to understate the true extent and persistence of disadvantage.

Early-Life Adversity Accelerates Child and Adolescent Development

Most developmental work regards adverse developmental experiences as forces that undermine well-being. Here, I present an alternative—or complementary—view, summarizing recent evidence on puberty, endocrinology, cellular aging, and brain connectivity that collectively reveals developmental acceleration in response to contextual adversity. Findings are cast in evolutionary-developmental terms, highlighting the trade-off between accelerated aging and (a) increased morbidity and (b) premature mortality.

Timing of puberty and reserve capacity in adolescence as pathways to educational level in adulthood-a longitudinal study

BACKGROUND

Family socioeconomic status (SES) is related to a child's educational success. Intermediate pathways for this relationship, such as through pubertal timing and reserve capacity, occur in adolescence.

AIM

To study whether family SES affects a child's adult education through a psychosocial and behavioural pathway (reserve capacity) and/or a biological pathway (pubertal timing) or only through school achievement in adolescence.

SUBJECTS AND METHODS

Finnish adolescents sampled in five cross-sectional surveys from 1985 to 1995 (n = 37,876) were followed through the Registry of Completed Education and Degrees until 2009, when they were 29-43 years old. Family SES data also came from this registry. Structural equation modelling adjusted for ages at baseline and follow-up was used.

RESULTS

Low family SES increased the probability of low adult education, delayed pubertal timing (in boys), weak reserve capacity and low school achievement. Reserve capacity and school achievement directly affected adult education and mediated the relationship of family SES with the outcome. Delayed pubertal timing predicted low adult education, except when school achievement was added to the model.

CONCLUSIONS

The results show that family SES affects the child's adult education level through psychosocial and biobehavioural pathways, but the biological pathway is mediated by school achievement.

Developmental Adaptation to Stress: An Evolutionary Perspective

The assumption that early stress leads to dysregulation and impairment is widespread in developmental science and informs prevailing models (e.g., toxic stress). An alternative evolutionary–developmental approach, which complements the standard emphasis on dysregulation, proposes that early stress may prompt the development of costly but adaptive strategies that promote survival and reproduction under adverse conditions. In this review, we survey this growing theoretical and empirical literature, highlighting recent developments and outstanding questions. We review concepts of adaptive plasticity and conditional adaptation, introduce the life history framework and the adaptive calibration model, and consider how physiological stress response systems and related neuroendocrine processes may function as plasticity mechanisms. We then address the evolution of individual differences in susceptibility to the environment, which engenders systematic person–environment interactions in the effects of stress on development. Finally, we discuss stress-mediated regulation of pubertal development as a case study of how an evolutionary–developmental approach can foster theoretical integration.

The impact of the Wenchuan earthquake on early puberty: a natural experiment

Background

The factors influencing pubertal timing have gained much attention due to a secular trend toward earlier pubertal onset in many countries. However, no studies have investigated the association between the Great earthquake and early puberty. We aimed to assess whether the Wenchuan earthquake is associated with early puberty, in both boys and girls.

Methods

We used data from two circles of a survey on reproductive health in China to explore the impact of the Wenchuan earthquake on early puberty , and a total of 9,785 adolescents (4,830 boys, 49.36%) aged 12-20 years from 29 schools in eight provinces were recruited. Wenchuan earthquake exposure was defined as those Sichuan students who had not experienced oigarche/menarche before May 12, 2008. Early puberty was identified as a reported onset of oigarche/menarche at 11 years or earlier. We tested the association between the Wenchuan earthquake and early puberty in boys and girls. Then, subgroup analysis stratified by the age at earthquake exposure also was performed.

Results

In total, 8,883 adolescents (4,543 boys, 51.14%) with a mean (SD) age of 15.13 (1.81) were included in the final sample. In general, children exposed to the earthquake had three times greater risk of early puberty (boys, RR [95% CI] = 3.18 [2.21-4.57]; girls: RR [95%CI] =3.16 [2.65-3.78]). Subgroup analysis showed that the adjusted RR was 1.90 [1.19-3.03] for boys and 2.22 [1.75-2.80] for girls. Earthquake exposure predicted almost a fourfold (RR [95%CI] = 3.91 [1.31-11.72]) increased risk of early puberty in preschool girls, whereas the increase was about twofold (RR [95%CI] = 2.09 [1.65-2.64]) in schoolgirls. Among boys, only older age at earthquake exposure was linked to early puberty (RR [95%CI] = 1.93 [1.18-3.16]).

Conclusions

Wenchuan earthquake exposure increased the risk of early puberty in boys and girls, and preschoolers were more at risk than schoolchildren. The implications are relevant to support policies for those survivors, especially children, to better rebuild after disasters.

Sex- and brain region-specific patterns of gene expression associated with socially-mediated puberty in a eusocial mammal

The social environment can alter pubertal timing through neuroendocrine mechanisms that are not fully understood; it is thought that stress hormones (e.g., glucocorticoids or corticotropin-releasing hormone) influence the hypothalamic-pituitary-gonadal axis to inhibit puberty. Here, we use the eusocial naked mole-rat, a unique species in which social interactions in a colony (i.e. dominance of a breeding female) suppress puberty in subordinate animals. Removing subordinate naked mole-rats from this social context initiates puberty, allowing for experimental control of pubertal timing. The present study quantified gene expression for reproduction- and stress-relevant genes acting upstream of gonadotropin-releasing hormone in brain regions with reproductive and social functions in pre-pubertal, post-pubertal, and opposite sex-paired animals (which are in various stages of pubertal transition). Results indicate sex differences in patterns of neural gene expression. Known functions of genes in brain suggest stress as a key contributing factor in regulating male pubertal delay. Network analysis implicates neurokinin B (Tac3) in the arcuate nucleus of the hypothalamus as a key node in this pathway. Results also suggest an unappreciated role for the nucleus accumbens in regulating puberty.

Childhood Socioeconomic Position and Pubertal Onset in a Cohort of Multiethnic Girls: Implications for Breast Cancer

Background: Higher socioeconomic position (SEP) has been associated with increased risk of breast cancer. Its relationship with earlier age of pubertal onset, a risk factor for breast cancer, is less clear.Methods: We studied the relationship of SEP to pubertal onset in a multiethnic cohort of 1,237 girls ages 6 to 8 years at baseline. Girls in three U.S. cities were followed for 5 to 8 years with annual clinical examinations from 2004 to 2012. SEP measures were examined for associations with pubertal onset, assessed by breast budding (thelarche) and pubic hair development (adrenarche). Analyses were conducted with accelerated failure time models using a Weibull distribution, with left, right, and interval censoring.Results: Higher body mass index percentage at entry to the study and black or Hispanic race/ethnicity were the strongest predictors of age at pubertal onset. An SEP index comprising household family income, mother's education, and home ownership was an independent predictor of thelarche in adjusted models for all girls together and for white and Latina, separately, but not black girls, and the relationship varied by study site. The SEP index was not related to adrenarche in adjusted models. Overall, girls from the lowest quintile of SEP entered puberty on average 6% earlier than girls from the highest quintile (time ratio = 0.94; 95% confidence interval 0.91-0.97) in adjusted models.Conclusions: Our results suggest that early-life SEP may influence the timing of pubertal development.Impact: Factors related to lower SEP in childhood can adversely affect early development in ways that may increase the risk of breast cancer. Cancer Epidemiol Biomarkers Prev; 26(12); 1714-21. ©2017 AACR.