Advanced Pubertal Development Research Articles

Clinical Features and Decision making of Congenital Vaginal Agenesis Combined with Cervical Aplasia: Case Report and Literature Review

Objective: To present the case of a teenage girl with vaginal agenesis and review current literature on recommended courses of action. A 12-year-old girl with KBG genetic syndrome was admitted to the Pediatric Unit with recurrent acute abdominal pain, vomiting, dehydration, and primary amenorrhea. Physical examination revealed advanced pubertal development, and a negative swab test. Magnetic Resonance Imaging (MRI) showed complete vaginal agenesis, septated uterus with cervical aplasia, hematometra, and hematosalpinx. Open hysterectomy was decided upon due to acute abdominal pain and the risk of endometriosis and infection. She progressed favorably and was discharged two days after surgery. Conclusion: Congenital complete vaginal agenesis with cervical aplasia is a rare obstructive malformation of the genital tract. Generally, hysterectomy is recommended due to the high risk of stenosis, infection, and adhesions. Vaginoplasty is an option when the patient is mature enough to undergo the procedure. Attempts to preserve the uterus and fertility in patients with complete cervical atresia have a small sample size. In this case, the decision to perform a hysterectomy was considered the most appropriate to suit her social circumstances.

BrainAGE as a measure of maturation during early adolescence

Abstract The Brain-Age Gap Estimation (BrainAGE) is an important new tool that purports to evaluate brain maturity when used in adolescent populations. However, it is unclear whether BrainAGE tracks with other maturational metrics in adolescence. In the current study, we related BrainAGE to metrics of pubertal and cognitive development using both a previously validated model and a novel model trained specifically on an early adolescent population. The previously validated model was used to predict BrainAGE in two age bands, 9-11 and 10-13 years old, while the novel model was used with 9-11 year olds only. Across both models and age bands, an older BrainAGE was related to more advanced pubertal development. The relationship between BrainAGE and cognition was less clear, with conflicting relationships across the two models. Additionally, longitudinal analysis revealed moderate to high stability in BrainAGE across early adolescence. The results of the current study provide initial evidence that BrainAGE tracks with some metrics of maturation, including pubertal development. However, the conflicting results between BrainAGE and cognition lead us to question the utility of these models for non-biological processes.

Sex Hormones associated with Temporomandibular Pain on Palpation in Male Adolescents - Results of the Epidemiologic LIFE Child Study.

This study aimed to investigate whether the sex steroid precursor hormone dehydroepiandrosterone sulfate (DHEA-S), sex hormone-binding globulin (SHBG), and testosterone (TT) are associated with temporomandibular (TM) pain on palpation in male adolescents. Out of the LIFE Child study dataset containing 1,022 children and adolescents aged 10 to 18 years (496 males, 48.5%), we used a subsample of 273 male adolescents (mean age: 13.8 ± 2.3 years) in advanced pubertal development (PD) to analyze the association between hormones and TM pain. The Tanner scale was applied to describe the stage of PD. Pain on palpation of the temporalis and masseter muscles and the TM joints (palpation pain) was assessed using the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Serum levels of sex hormones (DHEA-S, SHBG, TT) were determined using standardized laboratory analyses. Free TT was estimated from the ratio between TT and SHBG (free androgen index = FAI). We calculated the risk of perceived positive palpation pain for male participants as a function of hormone levels (DHEA-S, FAI) taking into account age and body mass index (BMI). Among more developed (Tanner stage 4-5) male adolescents, 22.7% (n=62) reported palpation pain in the TM region. In these participants, FAI levels were approximately half that of individuals without such pain (p<0.01). DHEA-S levels were about 30% lower in the pain group (p<0.01). In multivariable regression analyses, the odds ratio (OR) for pain on palpation decreased to 0.75 (95% confidence interval [CI]: 0.57-0.98) per 10 units of FAI level compared to those without pain, after controlling for the effects of age and adjusted BMI. We observed the same effect for this subgroup per unit of DHEA-S serum level (OR=0.71; 95% CI: 0.53-0.94). At subclinical lower levels of serum free TT and DHEA-S, male adolescents are more likely to report pain on standardized palpation of the masticatory muscles and/or TM joints. This finding supports the hypothesis that sex hormones may influence pain reporting.

Chronic stress in peer relationships moderates the association between pubertal development and neural response to emotional faces in adolescence

Adolescence is a period of heightened risk for multiple forms of psychopathology, partly due to greater exposure to interpersonal stress. One way that interpersonal stress may increase risk for psychopathology is by altering the normative development of neural systems that support socio-affective processing. The late positive potential (LPP) is an event-related potential component that reflects sustained attention to motivationally-salient information and is a promising marker of risk for stress-related psychopathology. However, it is not clear how the LPP to socio-affective information changes across adolescence, nor whether exposure to stress with peers interferes with normative developmental differences in the LPP to socio-affective content during this period. In 92 adolescent girls (10–19 years old), we assessed the LPP to task-irrelevant emotional and neutral faces, as well as behavioural measures of interference following the presentation of these faces. Adolescents at more advanced stages of puberty showed a smaller LPP to emotional faces, but adolescents exposed to greater peer stress exhibited a larger LPP to these stimuli. Additionally, for girls exposed to lower levels of peer stress, more advanced pubertal development was associated with a smaller LPP to emotional faces, whereas for girls exposed to higher levels of peer stress, the association between pubertal development and the LPP to emotional faces was not significant. Neither stress nor pubertal stage was significantly associated with behavioural measures. Combined, these data suggest that one pathway through which stress exposure increases risk for psychopathology during adolescence is by interfering with the normative development of socio-affective processing.

Impulsivity as a Predictor of Early Dating Initiation in 11-12-Year-Old Youth.

As early initiation of dating behaviors is associated with risky sexual behaviors (e.g., higher number of sexual partners, sex with strangers), the current study examined determinants of early dating behaviors, focusing on impulsivity. Participants were 11-12-year-old boys (n = 109) and girls (n = 61) recruited from a psychiatric clinic and ads targeted to the general public. Ordered logistic regression models were used to examine the association between each facet of impulsivity (negative urgency, positive urgency, lack of premeditation, lack of perseverance, and sensation seeking) and dating behaviors. Youth with higher sensation seeking and negative urgency was more likely to initiate dating behaviors at early ages compared to those with lower scores on those measures. Further, we found that female gender and higher parental education were associated with lower risk of initiating dating behaviors at early age. Advanced pubertal development was associated with higher risk for early dating. Our findings can inform prevention efforts, identifying sensation seeking and negative urgency as predictors of youths' early engagement in dating behaviors, which can be a precursor of early sexual debut and risky sexual behaviors.

Factors Underpinning the Shift to Eveningness during Early Adolescence: Pubertal Development and Family Conflicts

Biological and psychosocial factors have been related to the shift to eveningness during early adolescence but it is necessary to study them from a longitudinal perspective. This longitudinal study examined the contribution of these factors to the onset of a shift towards eveningness in early adolescence. A sample of 440 (49.9% boys) Spanish adolescents were assessed for pubertal development, family conflicts, and morningness/eveningness. The same measures were taken twice at the age of 12 and one year later (T1: M = 12.47, SD = 0.75 and T2: M = 13.64, SD = 0.78). Pubertal development and family conflicts were considered predictors of morningness/eveningness in a mixed-effects multilevel model. The developmental shift towards eveningness appeared in girls but not in boys. The shift was related to more advanced pubertal development and more conflicts in the family. This study has implications for shaping healthy sleep habits in adolescents and possible interventions focused on family dynamics.

Salivary testosterone in male and female youth with and without autism spectrum disorder: considerations of development, sex, and diagnosis

BackgroundPuberty is characterized by significant physical, hormonal, and psychological changes, which may be especially challenging for individuals with autism spectrum disorder (ASD). Although the etiology of ASD remains uncertain, studies suggest imbalances in hormones, such as testosterone, may modulate the autism phenotype. While differences in fetal and postnatal testosterone have been reported, there is limited literature regarding testosterone variations during adolescence in ASD. We investigated morning salivary testosterone levels in youth with ASD and typical development (TD) to explore hypothesized differences, expecting elevated hormonal levels in ASD compared to TD.MethodsYouth with ASD (n = 140) and TD (n = 104), ages 10 to 13 years, were enrolled as part of a longitudinal study on pubertal development. Pubertal stage was determined by gold standard physical examination, and salivary testosterone was collected in the morning immediately upon waking and 30 min after waking and averaged across 3 days. Diagnostic (ASD/TD) and sex (male/female) differences, as well as interactions with age and puberty, were examined using robust linear mixed effect models.ResultsYouth with ASD showed significantly elevated testosterone concentrations compared to same-age TD peers. After the inclusion of natural cubic splines to account for nonlinearity in age, a significant age-by-sex interaction emerged with distinct developmental slopes for males and females. At younger ages, females had higher testosterone, until about 11.5 years of age, when levels began to plateau, while male testosterone concentrations continued to rapidly increase and surpass females. As expected, more advanced pubertal development was associated with elevated testosterone. In contrast, no significant effect of parent-reported social communication symptoms was observed.LimitationsLimitations include an unequal sex distribution, non-representative sample (e.g., cognition and race/ethnicity), and inability to examine afternoon/evening testosterone due to detection limits.ConclusionsTestosterone may play a unique role in the presentation of ASD, especially during periods of dynamic hormonal changes including puberty. Inherent developmental (age, puberty) and sex-based (male, female) factors play a more prominent role in changes in testosterone levels during adolescence. Even so, future research is warranted to determine the differential expression and impact of exposure to excess testosterone during the pubertal transition for youth with ASD.

Dehydroepiandrosterone sulphate levels at 7 years old are positively associated with more advanced pubertal development between 10 and 13 years old in girls.

We aimed to explore the association between dehydroepiandrosterone sulphate (DHEAS) levels at age 7, pubertal development between ages 10 and 13, and age at menarche. This is alongitudinal study of 603 individuals (301 girls, 302 boys) from the Generation XXI cohort. Evaluation of the participants at ages 7, 10 and 13 included anthropometry and Tanner staging. Pubertal development between ages 10 and 13 was categorized using latent class analysis, based on Tanner stages. The association between DHEAS at age 7 and pubertal development between ages 10 and 13 was conducted with binomial logistic regression, adjusted for BMI z-score. The variation of age at menarche in relation to DHEAS levels at age 7, controlling for maternal age at menarche, birth weight z-score and BMI z-score, was estimated fitting a linear regression model. Pubertal development at ages 10-13 was categorized intotwo classes-Class 1 had a higher probability for the lower Tanner stage (less advanced sexual maturation) and Class 2 had a higher probability for the higher Tanner stage (more advanced sexual maturation). In girls, taking Class 1 as a reference, Class 2 was positively associated with BMI z-score and DHEAS. In boys, Class 2 was positively associated with BMI, but not with DHEAS. DHEAS levels at age 7 were negatively associated with age at menarche, after adjustment for maternal age at menarche, birth weight and BMI. In girls, but not in boys, DHEAS at age 7 was positively associated with more advanced pubertal development between ages 10 and 13, and with earlier age at menarche.

Intergenerational transmission of depression risk: Mothers' neural response to reward and history of depression are associated with daughters' neural response to reward across adolescence.

Impaired reward responsiveness, a construct of the RDoC positive valence systems (PVS), prospectively predicts depression onset and may therefore represent an important marker of risk. Neural structures implicated in reward processing undergo substantial change during adolescence, a period of heightened risk for depression, particularly for those with a family history of the disorder. However, it is not clear whether familial transmission of PVS functioning also changes across adolescence, nor whether a family history of depression influences normative development of the PVS. To address these questions, mothers and their adolescent daughters each completed a monetary reward guessing task while an electroencephalogram was recorded (N = 109 dyads). Daughters' pubertal status significantly moderated the association between mothers' and daughters' reward processing in the delta frequency, such that there was a negative association for daughters in early puberty that shifted toward a positive association in later puberty. Furthermore, for never-depressed daughters without a maternal history of depression, more advanced pubertal development was associated with increased reward-related power in the delta frequency, whereas, for daughters with a maternal history of depression, more advanced pubertal development was associated with reduced power in the delta frequency. These data indicate that biomarkers of risk for psychopathology may differ as a function of both familial risk and developmental status. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Prenatal Environmental Exposure to Persistent Organic Pollutants and Reproductive Hormone Profile and Pubertal Development in Dutch Adolescents.

Persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), may interfere with hormonal processes. Knowledge about the effects of prenatal exposure to PCBs and their hydroxylated metabolites (OH-PCBs) on pubertal development is limited. Therefore, the aim of the current study was to determine whether prenatal environmental PCB and OH-PCB exposure are associated with reproductive hormone levels and pubertal characteristics in 13- to 15-year-old children. In this Dutch observational cohort study, 194 mother–infant pairs were included (1998–2002). Maternal pregnancy serum levels of PCBs, OH-PCBs, and other POPs were measured. At follow-up (2014–2016), we measured serum or plasma levels of reproductive hormones in their children. We assessed Tanner stages and testicular volume (by clinician or standardized self-assessment), and participants completed questionnaires on pubertal onset. In total, 101 adolescents (14.4 ± 0.8 years; 53.7% of invited) participated, and 55 were boys. In boys, higher prenatal PCB levels were associated with higher testosterone levels, higher pubic hair stage, larger testicular volume, and younger age at onset of growth spurt and voice break. In girls, higher prenatal PCB levels were associated with higher stages for breast development. In conclusion, higher prenatal PCB exposure could be associated with more advanced pubertal development in 13- to 15-year-old children.

Risk for social anxiety in early adolescence: Longitudinal impact of pubertal development, appearance comparisons, and peer connections.

ObjectivesThe aims of this study were to determine the impact of adolescent-relevant risk factors on changes in social anxiety symptoms from pre-to early-adolescence. MethodsFrom 2016 to 2018, 528 youth (51% boys) were tested in three annual waves across grades 6, 7, and 8 (M ages 11.2, 12.7, 13.7 years). Through online surveys youth reported on peer relationships that were combined into two latent factors: 1) appearance comparisons, comprising youth reports of appearance comparisons relative to others in general and while using social media, along with perceived attractiveness; and 2) positive peer connections, comprising youth reports of group affiliation, school belonging, and peer victimisation. Youth and their parents also reported on the youth's level of pubertal development as well as the youth's level of social anxiety using previously validated questionnaires. Social anxiety was also assessed with structured diagnostic interview. ResultsSeparate cross-lagged panel models were used to model longitudinal associations between all risk factors and youth, parent, and interviewer-reported measures of social anxiety. Of the associations tested, only appearance comparisons directly predicted increases in social anxiety symptoms 12 months later across all models. More advanced pubertal development was associated with increased appearance comparisons the following year. On the other hand, higher levels of social anxiety predicted subsequent reductions in positive peer connections in parent and interviewer models. ConclusionsThese results highlight the important and interconnected impact of pubertal development and appearance comparisons on both the development of social anxiety symptoms during early adolescence, as well as the social consequences of social anxiety.

Modeling environment through a general exposome factor in two independent adolescent cohorts.

Exposures to perinatal, familial, social, and physical environmental stimuli can have substantial effects on human development. We aimed to generate a single measure that capture's the complex network structure of the environment (ie, exposome) using multi-level data (participant's report, parent report, and geocoded measures) of environmental exposures (primarily from the psychosocial environment) in two independent adolescent cohorts: The Adolescent Brain Cognitive Development Study (ABCD Study, N = 11 235; mean age, 10.9 years; 47.7% females) and an age- and sex-matched sample from the Philadelphia Neurodevelopmental Cohort (PNC, N = 4993). We conducted a series of data-driven iterative factor analyses and bifactor modeling in the ABCD Study, reducing dimensionality from 348 variables tapping to environment to six orthogonal exposome subfactors and a general (adverse) exposome factor. The general exposome factor was associated with overall psychopathology (B = 0.28, 95% CI, 0.26-0.3) and key health-related outcomes: obesity (odds ratio [OR] , 1.4; 95% CI, 1.3-1.5) and advanced pubertal development (OR, 1.3; 95% CI, 1.2-1.5). A similar approach in PNC reduced dimensionality of environment from 29 variables to 4 exposome subfactors and a general exposome factor. PNC analyses yielded consistent associations of the general exposome factor with psychopathology (B = 0.15; 95% CI, 0.13-0.17), obesity (OR, 1.4; 95% CI, 1.3-1.6), and advanced pubertal development (OR, 1.3; 95% CI, 1-1.6). In both cohorts, inclusion of exposome factors greatly increased variance explained in overall psychopathology compared with models relying solely on demographics and parental education (from <4% to >38% in ABCD; from <4% to >18.5% in PNC). Findings suggest that a general exposome factor capturing multi-level environmental exposures can be derived and can consistently explain variance in youth's mental and general health.

The onset of pubertal development and actigraphy-assessed sleep during middle childhood: Racial, gender, and genetic effects

ObjectiveThis study (1) examined pubertal development in relation to actigraphy-assessed sleep in twin children, and tested whether associations differed by child race and gender, (2) modeled genetic and environmental influences on pubertal development and sleep indicators, and (3) examined genetic and environmental influences on the covariation of puberty and sleep. DesignThe classic twin design was used to examine genetic and environmental contributions to puberty and sleep and their associations. SettingData were collected from community-dwelling urban and rural families of twins in the southwestern U.S. ParticipantsThe racially and socioeconomically diverse sample included 596 twin children (Mage = 8.41, SD = 0.69; 51.7% female; 66.3% white; 33.7% Hispanic; 170 monozygotic, 236 same-sex dizygotic, 188 opposite-sex dizygotic). MeasurementsPubertal development was assessed via parent report. Children wore actigraph watches for 7 nights (M = 6.81, SD = 0.67) to capture sleep duration, efficiency, midpoint, onset latency, and duration variability. ResultsIn contrast to extant literature with older youth, more advanced pubertal development was associated with longer sleep durations in Hispanic and white girls and higher sleep efficiency in white girls, though Hispanic girls demonstrated later sleep midpoints. Pubertal development was moderately heritable and there was a genetic influence on the covariance between puberty and sleep indicators. ConclusionsThis was the first study to examine the genetic and environmental influences on the covariation between puberty and sleep, and found genetic underpinnings between pubertal development and actigraphy-assessed sleep duration and efficiency, though sleep and puberty were almost entirely independent in twins at this age.

The Chinese Adolescent Cohort Study: Design, Implementation, and Major Findings.

The importance of diet quality on children's growth is being increasingly recognized. The Chinese Adolescent Cohort (CAC) is a longitudinal cohort study to comprehensively investigate the health impacts of nutritional factors on child growth. From 2013 to 2018, 6,967 children aged 6–8 years have been recruited from 23 primary schools in Sichuan, Guizhou, and Chongqing, which have been planned to be followed up annually until their age of 15 years. Regular assessments included the measurement of height, weight, waist circumference, and skinfold thicknesses; pubertal development was examined by trained investigators according to Tanner stages; dietary intake was obtained by three 24-h recalls and food frequency questionnaire; validated questionnaires were used to estimate socio-demographic characteristics, physical activity, and sedentary behaviors. Findings from the CAC baseline and the first follow-up data suggested that higher protein intake among girls and unhealthy eating habits among children might increase the risk for childhood obesity. Also, higher intakes of grain and meat and lower overall diet quality and intakes of dietary fiber and tuber might be associated with advanced pubertal development. Those results indicated that the CAC study could contribute to the development of strategies for optimizing Chinese children's health.

143 The Shared and Unique Genetic Influences of Pubertal Development and Objective Sleep During Middle Childhood

Abstract Introduction More advanced pubertal development has negative impacts on sleep quality and quantity in adolescents (Foley et al., 2018). Pubertal development and sleep both have high genetic influences, while environmental factors are also evident (Breitenstein et al., 2020; Dick et al., 2001). To elucidate underlying relations between pubertal development and sleep, the present study examined the genetic and environmental influences on the covariation of these health processes using a twin study design. Methods This racially and socioeconomically diverse sample included 596 twin children (Mage=8.41, SD=.69; 51.7% female; 66.3% White; 33.7% Hispanic; 156 monozygotic, 217 same-sex dizygotic, and 179 opposite-sex dizygotic). Children wore wrist-based accelerometers (Motion Logger Micro Watch; Ambulatory Monitoring, Inc, Ardsley, NY USA) on their non-dominant wrist for 7 nights (M= 6.81, SD= .67) to measure their sleep (efficiency, duration). Primary caregivers completed Zygosity Questionnaire for Young Twins (Goldsmith, 1991), as well as the Pubertal Development Scale (Petersen et al., 1988) for each twin, and puberty composite scores for males and females were used (Coleman &amp; Coleman, 2002). Bivariate Cholesky decompositions were fit in OpenMX to estimate genetic and environmental influences on the covariance between pubertal development and sleep (Boker et al., 2011). The -2 log-likelihood chi-square test of fit and the Akaike’s Information Criterion were used to find the most parsimonious solution. Results 261 White (68.9%) and 135 Hispanic (77.1%) participants had initiated puberty. Pubertal development was positively correlated with sleep efficiency (r =.15) and sleep duration (r =.15). Pubertal development, sleep efficiency, and sleep duration were all heritable at 59%, 54%, and 73%, respectively. The AE-A-AE twin model was the best-fitting model for both bivariate models, with additive genetics accounting for 86% and 90% of the shared covariance between pubertal development and sleep efficiency and duration, respectively. Conclusion The genetic association between pubertal development and sleep suggests a third variable influence, and Wang and colleagues (2020) have identified genetic variants that partially explain the association. Future directions include longitudinal analyses across the pubertal transition as environmental demands increase. Support (if any) Supported by the US Eunice Kennedy Shriver National Institute of Child Health and Human Development: R01 HD079520 to Kathryn Lemery-Chalfant and Leah Doane.

Low BMI, but not high BMI, influences the timing of puberty in boys.

Previous studies investigating the association between weight status and onset of puberty in boys have been equivocal. It is currently unclear to what extent weight class influences puberty onset and progression. To explore the relationship between degree of sexual maturation and anthropometric measures in Norwegian boys. The following endpoints were collected in a Norwegian cross-sectional study of 324 healthy boys aged 9-16: ultrasound-determined testicular volume (USTV), total serum testosterone, Tanner pubic hair stage, height, weight, waist circumference (WC), subscapular skinfolds (SSF), and body fat percentage (%BF). Testicular volume-for-age z-scores were used to classify "early," "average," or "late" maturing boys. Ordinal logistic regression analyses with a proportional odds model were applied to analyze the association between anthropometric variables and age-adjusted degree of pubertal development, with results expressed as age-adjusted odds ratios (AOR). Cumulative incidence curves for reaching pubertal milestones were stratified by BMI. Boys with a low BMI for age (BMIz <-1) were less likely to have reached a pubertal testicular volume (USTV≥2.7mL) or a pubertal serum level of testosterone (≥0.5nmol/L) compared to normal weight boys (AOR 0.3, p=0.038, AOR 0.3, p=0.026, respectively), and entered puberty on average with a delay of approximately eight months. Boys with high BMI for age (BMIz >1) exhibited a comparable timing as normal weight boys. The same was found for WC. Pubertal markers were not associated with SSF or %BF. By examining the association between puberty and weight status classified as low, average, or high, we found that a low BMI or WC for age were associated with a less advanced pubertal development and delayed timing of puberty in boys. No significant association was observed for a high BMI or WC. Moreover, no significant effects of SSF or %BF were observed. A low weight status should also be considered when assessing pubertal development in boys.

A longitudinal study investigating trajectories of sensitivity to threat over time and their association with alpha asymmetry among children and adolescents

Research has yet to investigate trajectories of sensitivity to threat across childhood and adolescence. Further, neural associations of these trajectories remain unknown. The current 3-year study used a latent class growth curve analysis to investigate whether there were distinct trajectories of sensitivity to threat among children and adolescents over time (N = 363; age range at Time 1 = 8–14). We also examined whether alpha asymmetry (a neural index of motivational tendencies) was associated with the different trajectories. Results revealed three distinct trajectory groups (1) high-stable sensitivity to threat, (2) moderate-increasing sensitivity to threat and (3) low-stable sensitivity to threat. The high-stable sensitivity to threat group had greater right frontal asymmetry activation (i.e., greater neural avoidance motivation) than the other two groups. Additionally, females, those with higher parental education, and individuals with more advanced pubertal development (but not age) had greater odds of being part of the high-stable sensitivity to threat group compared to the other groups. Of interest, puberty rather than age may be an important indicator of heightened sensitivity to threat.

\u2018Social screens\u2019 and \u2018the mainstream\u2019: longitudinal competitors of non-organized physical activity in the transition from childhood to adolescence

BackgroundPhysical activity (PA) tends to decline during late childhood and adolescence. In Australia, this decline has been shown to occur particularly in non-organized PA (e.g. active play and informal sport). Using a social marketing approach, segments of youth may be identified and targeted based on their profile of alternative activities that compete with non-organized PA during the transition to adolescence. The objectives of this study were to identify and describe segments of youth whose participation in non-organized PA declined between 11 and 13 years, based on changes in other potential competing activities during this period.MethodsData were sourced from Waves 4 and 5 of the Longitudinal Study of Australian Children. Participation in non-organized PA and thirteen alternative activities (e.g. video games, homework, sleep) were measured using 24-h time-use diaries. Analyses were limited to participants whose non-organized PA had declined between 11 and 13 years (n = 1043). Two-stage cluster analysis was conducted and segments were described using chi-square and t-tests.ResultsAmong the analytic sample, average non-organized PA participation declined by 87 min/day between 11y and 13y (p < 0.001). Two segments were identified (κ = 0.66). The ‘Social Screens’ segment (n = 143) had large increases in texting, emailing and social media use (+ 56 min/day, p < 0.001) and other internet use (+ 32 min/day, p < 0.001). Conversely, ‘the Mainstream’ segment (n = 900) had smaller increases in a wider range of activities, including other PA (organized PA, active transport, active chores/work) (+ 16.0 min/day, p < 0.001), homework/study (+ 9.5 min/day, p < 0.001) and electronic gaming (+ 6.7 min/day, p < 0.05). ‘Social Screens’ were more likely to attend public school, live in urban areas and have more advanced pubertal development (girls only). ‘The Mainstream’ were more likely to participate in PA and out-of-school activities.ConclusionsThe ‘Social Screens’ segment had a much larger increase in texting, emailing, social media and other internet use, and lower participation in overall PA and out-of-school activities, compared with ‘the Mainstream’. Future research may trial PA promotion strategies to replace benefits that this segment may seek in competing activities (e.g. social PA apps).

Differences in genetic and environmental influences on body weight and shape concerns across pubertal development in females

The heritability of disordered eating increases during puberty; however, prior studies have largely examined a composite score of disordered eating, rather than specific symptoms. Body weight and shape concerns cut across all eating disorder diagnoses and are some of the strongest prospective risk factors for the development of eating disorders. Yet, little is known about potential developmental increases or decreases in genetic and environmental influences for these key symptoms. This study examined differences in genetic and environmental effects on a range of body weight and shape concerns during puberty and compared results to findings for overall levels of disordered eating symptoms. Participants were 926 same-sex female twins (ages 8–16) from the Michigan State University Twin Registry. Well-validated questionnaires were used to examine pubertal maturation, overall levels of disordered eating, and a range of cognitive body weight/shape constructs: body dissatisfaction, weight/shape concerns, and weight preoccupation. Findings for overall levels of disordered eating were very similar to those obtained in previous work, with significantly increased genetic effects in girls at more advanced pubertal development. Importantly, these same pubertal increases in genetic influences were observed for body dissatisfaction and weight/shape concerns. However, no pubertal moderation of genetic effects was observed for weight preoccupation; instead, pubertal moderation of nonshared and shared environmental effects was observed. Our findings point to differences in the extent to which genetic and environmental factors contribute to various cognitive body weight and shape symptoms during puberty.

Pubertal Maturation and Trajectories of Depression During Early Adolescence.

Beginning at puberty, prevalence of depression in females rises dramatically. The physical changes of puberty coincide with a period of social flux, during which relationships become less stable and more prone to conflict. While this social upheaval is normatively distressing for girls, it may be especially so for girls with cognitive styles that leave them more susceptible to depression. The present study investigated depressive symptoms at two time points during early pubertal maturation. N = 110 girls (Mage = 11.57, SD = 0.98) reported on depressive symptomology, pubertal maturation, ruminative coping style, frequency of peer conflict, and rejection sensitivity. Multivariate analyses suggest more advanced pubertal development and greater rejection sensitivity at Time 1 predicted higher levels of depressive symptoms at Time 2, after accounting for baseline levels of depressive symptoms and all other social and cognitive correlates of depression. This effect was also found in early maturing girls. Menarche status was not significant. Since menarche occurs toward the end of puberty, results suggest that risk for worsening depression is not associated with completing puberty, or with menstruation itself. Rather, increases in depressive symptoms seem to be associated with physical changes that emerge early in the pubertal transition, especially for early maturing girls, paired with anticipatory concerns about social rejection.