Early puberty and early sexual activity are associated with bulimic-type eating pathology in middle adolescence

Adolescent neurocognitive development and decision-making abilities regarding gender-affirming care

Recently, politicians and legislative bodies have cited neurodevelopmental literature to argue that brain immaturity undermines decision-making regarding gender-affirming care (GAC) in youth. Here, we review this literature as it applies to adolescents' ability to make decisions regarding GAC. The research shows that while adolescence is a time of peak risk-taking behavior that may lead to impulsive decisions, neurocognitive systems supporting adult-level decisions are available given deliberative processes that minimize influence of short-term rewards and peers. Since GAC decisions occur over an extended period and with support from adult caregivers and clinicians, adolescents can engage adult-level decision-making in this context. We also weigh the benefits of providing GAC access during adolescence and consider the significant costs of blocking or delaying GAC. Transgender and non-binary (TNB) adolescents face significant mental health challenges, many of which are mitigated by GAC access. Further, initiating the GAC process during adolescence, which we define as beginning at pubertal onset, leads to better long-term mental health outcomes than waiting until adulthood. Taken together, existing research indicates that many adolescents can make informed decisions regarding gender-affirming care, and that this care is critical for the well-being of TNB youth. We highlight relevant considerations for policy makers, researchers, and clinicians.

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.

Sexual self-concept, functioning, and practices of women with binge eating episodes

PURPOSE

Positive sexuality has received little empirical attention in relation to eating disorders. Two tendencies related to sexuality have been identified among women with anorexia nervosa (avoidance) and bulimia nervosa (disinhibition), but it is unclear if they also apply to women with binge eating episodes without compensatory behaviors. This study aimed at (1) exploring the sexual self-concept, functioning, and practices of women with binge eating episodes with or without comorbid restrictive and/or compensatory behaviors, considering past experiences of violence, and (2) verifying the presence of distinct profiles of sexual dispositions among this population.

METHODS

In total, 253 women reporting recurrent episodes of loss of control related to food intake in the past 5 years, completed a web-based questionnaire. Descriptive and correlational analyses were conducted to outline participants' sexual self-concept, functioning, and practices and to examine the relationship between these factors. A two-step cluster analysis was also performed to determine whether participants presented distinct profiles of sexual dispositions.

RESULTS

Participants were generally characterized by a negative sexual self-concept and poor sexual functioning. While a first subgroup of participants displayed a pattern of sexual difficulties and avoidance, a second subgroup had a positive sexual self-concept, better sexual functioning and a wider range of sexual practices. Subgroups did not differ relative to binge eating.

CONCLUSIONS

Sexuality offers a platform for positive embodiment, which can lead to the improvement of body image and mind-body connection and may thus constitute an essential clinical target to improve treatment related to binge eating episodes.

LEVEL OF EVIDENCE

Level II: The experimental study is a non-randomized controlled trial.

The effects of obesity on the menstrual cycle

The prevalence of childhood and adolescent obesity has significantly increased in the United States and worldwide since the 1970s, a trend that has been accelerated by the COVID-19 pandemic. The complications of obesity range from negative effects on the cardiovascular, endocrine, hepatobiliary, and musculoskeletal systems to higher rates of mental health conditions such as depression and eating disorders among affected individuals. Among adolescent girls, childhood obesity has been associated with the earlier onset of puberty and menarche, which can result in negative psychosocial consequences, as well as adverse effects on physical health in adulthood. The hormones leptin, kisspeptin and insulin, and their actions on the hypothalamic-pituitary-ovarian axis, have been implicated in the relationship between childhood obesity and the earlier onset of puberty. Obesity in adolescence is also associated with greater menstrual cycle irregularity and the polycystic ovary syndrome (PCOS), which can result in infrequent or absent menstrual periods, and heavy menstrual bleeding. Hyperandrogenism, higher testosterone and fasting insulin levels, and lower levels of sex hormone-binding globulin, similar to the laboratory findings seen in patients with PCOS, are also seen in individuals with obesity, and help to explain the overlap in phenotype between patients with obesity and those with PCOS. Finally, obesity has been associated with higher rates of premenstrual disorders, including premenstrual syndrome and premenstrual dysphoric disorder, and dysmenorrhea, although the data on dysmenorrhea appears to be mixed. Discussing healthy lifestyle changes and identifying and managing menstrual abnormalities in adolescents with obesity are key to reducing the obstetric and gynecologic complications of obesity in adulthood, including infertility, pregnancy complications, and endometrial cancer.

Risk of eating disorders in a representative sample of Italian adolescents: prevalence and association with self-reported interpersonal factors

PURPOSE

Adolescence represents a critical period for the onset of eating disorders (EDs). The present study aimed to provide the prevalence of individuals at risk for EDs psychopathology in a representative population of adolescents aged 14-19 and to characterize this population regarding interpersonal and psychological factors.

METHODS

The percentage of participants at risk for EDs in a representative high school population was assessed through the SCOFF screening questionnaire (cut-off score: 3) in the total sample (N: 6551) and in gender-based subgroups for different body mass index (BMI) categories. Odds ratios for being at risk of ED (SCOFF ≥ 3) were esteemed in a multivariable analysis including self-reported parental education, quality of family and peer relationships, bullying victimization, age at first sexual intercourse, and psychological distress.

RESULTS

A SCOFF score ≥ 3 was found in 31.0% of participants (boys: 19.4%; girls: 44.6%), with a greater prevalence among higher BMI categories. Bad family relationships, being bullied, having the first sexual intercourse before the age of 14, and experiencing high distress were associated with this risk condition. Among girls, bad peer relationships were associated with a low-risk SCOFF score.

CONCLUSION

A remarkable percentage of adolescents reported significant body image or eating concerns. Screening programs are deeply needed, and particular attention should be devoted to interpersonal factors, such as the quality of family relationships and interactions with peers, which represent potential indicators of this vulnerability.

LEVEL OF EVIDENCE

Level V - Cross-sectional study.

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.

Earlier onset of menstruation is related to increased body mass index in adulthood and altered functional correlations between visual, task control and somatosensory brain networks

Later onset of puberty has been associated with lower body mass index (BMI) in adulthood independent of childhood BMI. However, how the relationship between time of onset of puberty and BMI in adulthood is associated with neurocognitive outcomes is largely unstudied. In the present study, women were sampled from the Human Connectome Project 1200 parcellation, timeseries and netmats1 release (PTN) release. Inclusion criteria were: four (15 minutes) resting state fMRI scans, current measured BMI, self-reported age at onset of menstruation (a proxy of age at onset of puberty) and no endocrine complications (eg, polycystic ovarian syndrome). The effect of age at onset of menstruation, measured BMI at scan date and the interaction of age at onset of menstruation by BMI on brain functional correlation was modelled using fslnets (https://fsl.fmrib.ox.ac.uk/fsl/fslwiki/FSLNets) controlling for race and age at scan. Corrected significance was set at a family-wise error probability (pFWE) < 0.05. A final sample of n = 510 (age 29.5 years ± 3.6, BMI at scan 25.9 ± 5.6 and age at onset of menstruation 12.7 ± 1.6 were included. Age at onset of menstruation was negatively associated with BMI at scan (r = - 0.19, P < 0.001). The interaction between age at onset of menstruation and BMI at scan was associated with stronger correlation between a somatosensory and visual network (t = 3.45, pFWE = 0.026) and a visual network and cingulo-opercular task control network (t = 4.74, pFWE = 0.0002). Post-hoc analyses of behavioural/cognitive measures showed no effect of the interaction between BMI and age at onset of menstruation on behavioural/cognitive measures. However, post-hoc analyses of heritability showed adult BMI and the correlation between the visual and somatosensory networks have high heritability. In sum, we report increased correlation between visual, taste-associated and self-control brain regions in women at high BMI with later age at onset of menstruation.

Polycystic Ovary Syndrome: A Brain Disorder Characterized by Eating Problems Originating during Puberty and Adolescence

Polycystic ovary syndrome (PCOS) is an endocrine condition associated with reproductive and psychiatric disorders, and with obesity. Eating disorders, such as bulimia and recurrent dieting, are also linked to PCOS. They can lead to the epigenetic dysregulation of the hypothalamic-pituitary-gonadal (HPG) axis, thereby impacting on ovarian folliculogenesis. We postulate that PCOS is induced by psychological distress and episodes of overeating and/or dieting during puberty and adolescence, when body dissatisfaction and emotional distress are often present. We propose that upregulated activation of the central HPG axis during this period can be epigenetically altered by psychological stressors and by bulimia/recurrent dieting, which are common during adolescence and which can lead to PCOS. This hypothesis is based on events that occur during a largely neglected stage of female reproductive development. To date, most research into the origins of PCOS has focused on the prenatal induction of this disorder, particularly in utero androgenization and the role of anti-Müllerian hormone. Establishing causality in our peripubertal model requires prospective cohort studies from infancy. Mechanistic studies should consider the role of the gut microbiota in addition to the epigenetic regulation of (neuro) hormones. Finally, clinicians should consider the importance of underlying chronic psychological distress and eating disorders in PCOS.

The First Ejaculation: A Male Pubertal Milestone Comparable to Menarche?

Boys experience their first ejaculation (thorarche) during adolescence, but this event is often overlooked as a milestone in male adolescent development. The purpose of this article is to draw attention to thorarche and consider it in comparison with the female milestone of menarche. A critical analysis is provided of how thorarche has been interpreted to date and the complexities in construing thorarche from a biological perspective are outlined. Despite potential tenability of characterizing thorarche as a comparable milestone to menarche, two particular points challenge this notion: (a) While thorarche may befall the boy involuntarily, it may also be induced by the boy's own will; and (b) Thorarche occurs concomitantly with (pubertal) orgasmarche and has an innate connection with sexuality. The answer to the title question remains contentious, but open topics for future research are noted throughout the article as essential steps towards attaining a better understanding of thorarche.

Relationships between eating disorder psychopathology, sexual hormones and sexual behaviours

A growing body of evidences demonstrated that sexuality is an important topic in the clinical research of eating disorders (EDs), due to its association with specific psychopathological features, and etiological factors. The present review took into consideration the complex relationship between sexual behaviours, hormonal alterations and EDs psychopathology. Studies pertaining sexual behaviours in EDs were divided into those focusing on sexual dysfunctions, and those related to risky sexual behaviours. The limited number of studies on sexual dysfunctions, reported a controversial association with weight status and hormonal alterations, and a clear relationship with severity of specific psychopathology (e.g. body image disturbance). Risky sexual behaviours have been associated with impulsivity and dissociation, as well as with abnormal stress response. Finally, both restriction and uncontrolled eating have been found to be responsible for several complex metabolic alterations, determining varied sexual and gynecologic problems, such as amenorrhea, hypogonadism, genital vascular problems, infertility, and miscarriage, although it is also possible that alterations in feeding and stress hormones contribute to altered eating behaviour.

Heritability of Age at Menarche in South Korean Female Twins

Genetic and environmental influences on age at menarche (AAM) have rarely been examined in Asian females. This study aimed to investigate the heritability of AAM in South Korean female twins. The AAM data from 1370 female twins (933 monozygotic [MZ] twins, 294 dizygotic [DZ] twins and 160 female members of opposite-sex DZ twins) born between 1988 and 2001 were analyzed. The age of the sample at the time of the assessment ranged from 16 to 28 years with a mean of 19.3 (SD = 2.2) years. The mean AAM in the total sample was 12.49 (SD = 1.41) years. Although the mean AAM decreased with increasing birth years, it levelled off in birth years 2000-2001. Maximum likelihood MZ and DZ twin correlations were 0.72 [95% CI (0.67, 0.76)] and 0.35 [95% CI (0.19, 0.50)], respectively. The results of model-fitting analysis indicated that the additive genetic and individual-specific environmental effects were 72% [95% CI (67%, 76%)] and 28% [95% CI (24%, 33%)], respectively. Neither nonadditive genetic nor shared environmental effects were significant.

Evolutionary Psychology of Eating Disorders: An Explorative Study in Patients With Anorexia Nervosa and Bulimia Nervosa

Prior research on non-clinical samples has lent support to the sexual competition hypothesis for eating disorders (SCH) where the drive for thinness can be seen as an originally adaptive strategy for women to preserve a nubile female shape, which, when driven to an extreme, may cause eating disorders. Restrictive versus impulsive eating behavior may also be relevant for individual differences in allocation of resources to either mating effort or somatic growth, reflected in an evolutionary concept called “Life History Theory” (LHT). In this study, we aimed to test the SCH and predictions from LHT in female patients with clinically manifest eating disorders. Accordingly, 20 women diagnosed with anorexia nervosa (AN), 20 with bulimia nervosa (BN), and 29 age-matched controls completed a package of questionnaires comprising measures for behavioral features and attitudes related to eating behavior, intrasexual competition, life history strategy, executive functioning and mating effort. In line with predictions, we found that relatively faster life history strategies were associated with poorer executive functioning, lower perceived own mate value, greater intrasexual competition for mates but not for status, and, in part, with greater disordered eating behavior. Comparisons between AN and BN revealed that individuals with BN tended to pursue a “fast” life history strategy, whereas people with AN were more similar to controls in pursuing a “slow” life history strategy. Moreover, intrasexual competition for mates was significantly predicted by the severity of disordered eating behavior. Together, our findings lend partial support to the SCH for eating disorders. We discuss the implications and limitations of our study findings.

Timing of spermarche and menarche among urban students in Guangzhou, China: trends from 2005 to 2012 and association with Obesity

In Guangzhou, China, whether the trend of a decreasing pubertal age has continued in recent years remained unknown, and the association between obesity and early puberty was still controversial. Herein, we conducted a serial cross-sectional study using data from physical fitness surveillance (2005–2012), to determine the recent trends in age at spermarche and menarche among students in Guangzhou, and to investigate whether elevated BMI modified timing of spermarche and menarche. This study included 1,278,258 urban students. In boys, no significant differences were observed in median ages of spermarche (MAS) from 2005 to 2012, with overlapping 95% CIs. Similar results were observed for median ages of menarche (MAM) in girls. The Cox-Stuart trend test showed neither upward nor downward shift in MAS and MAM over time (P = 0.625; 1.000). Each year, both MAS and MAM decreased with increasing BMI. Furthermore, a higher BMI was associated with early age at spermarche and menarche, with ORs of 1.052 (95% CI = 1.045–1.059) and 1.233 (95% CI = 1.220–1.247) in 2012 for boys and girls, respectively. In conclusion, the pubertal timing has been stable in urban students from 2005 to 2012. Furthermore, obesity was associated with early timing of spermarche and menarche.

Identification of differential genomic DNA Methylation in the hypothalamus of pubertal rat using reduced representation Bisulfite sequencing

BACKGROUND

There are many variables affecting the onset of puberty in animals, including genetic, nutritional, and environmental factors. Recent studies suggest that epigenetic regulation, especially DNA methylation, plays a majorrole in the regulation of puberty. However, there have been no reports on DNA methylation of the pubertal genome.

METHODS

We investigated DNA methylation in the female rat hypothalamus at prepuberty and puberty using reduced representation bisulfite sequencing technology. The identified genes and signaling pathways exhibiting changes to DNA methylation in pubertal rats were determined by Gene Ontogeny and Kyoto Encyclopedia of Genes and Genomes analysis.

RESULTS

The distribution of the three types of methylated C bases in promoter and CpG island (CGI) regions in the hypothalamus was as follows: 87.79% CG, 3.05% CHG, 9.16% CHH for promoters, and 88.35% CG, 3.21% CHG, 88.35% CHH for CGI in prepubertal rats; and 90.78% CG, 2.13% CHG, 7.09% CHH for promoters, and 88.59% CG, 88.59% CHG, 8.35% CHH for CGI in pubertal animals. CG showed the highest percentage of methylation, and was the highest methylation state in CGI. Compared to prepubertal hyoyhalamus samples, we identified ten genes with altered methylation in promoter regions in the pubertal hypothalamus samples, and 43 genes with altered methylation in the CGI. Changes in DNA methylation were found in gonadotropin-releasing hormone signaling pathways, and the oocyte meiosis pathway.

CONCLUSION

Our results demonstrate changes in DNA methylation occur in female rats from prepuberty to puberty suggestng DNA methylation may play a crucial role in the regulation of puberty onset. This study provides essential information for future studies on the role of epigenetics in the regulation of puberty.

Comparison of Clinical, Maternal, and Self Pubertal Assessments: Implications for Health Studies

BACKGROUND

Most epidemiologic studies of puberty have only 1 source of pubertal development information (maternal, self or clinical). Interpretation of results across studies requires data on reliability and validity across sources.

METHODS

The LEGACY Girls Study, a 5-site prospective study of girls aged 6 to 13 years (n = 1040) collected information on breast and pubic hair development from mothers (for all daughters) and daughters (if ≥10 years) according to Tanner stage (T1-5) drawings. At 2 LEGACY sites, girls (n = 282) were also examined in the clinic by trained professionals. We assessed agreement (κ) and validity (sensitivity and specificity) with the clinical assessment (gold standard) for both the mothers' and daughters' assessment in the subcohort of 282. In the entire cohort, we examined the agreement between mothers and daughters.

RESULTS

Compared with clinical assessment, sensitivity of maternal assessment for breast development was 77.2 and specificity was 94.3. In girls aged ≥11 years, self-assessment had higher sensitivity and specificity than maternal report. Specificity for both mothers and self, but not sensitivity, was significantly lower for overweight girls. In the overall cohort, maternal and daughter agreement for breast development and pubic hair development (T2+ vs T1) were similar (0.66, [95% confidence interval 0.58-0.75] and 0.69 [95% confidence interval 0.61-0.77], respectively), but declined with age. Mothers were more likely to report a lower Tanner stage for both breast and pubic hair compared with self-assessments.

CONCLUSIONS

These differences in validity should be considered in studies measuring pubertal changes longitudinally when they do not have access to clinical assessments.

Age at menarche, reactions to menarche and attitudes towards menstruation among Mexican adolescent girls

OBJECTIVE

To investigate the relationships between menarcheal timing and both menarcheal experience and attitudes toward menstruation in Mexican girls.

DESIGN

Cross-sectional survey.

SETTINGS

Sample of adolescents attending 10 different public schools.

PARTICIPANTS

Mexican postmenarcheal adolescents, aged 11-16 years.

INTERVENTION

Participants answered 1 questionnaire about menarcheal experience and another about attitudes towards menstruation.

RESULTS

Early maturers (menarche before 11 years) were more likely than average (menarche at 11 or 12 years) or late maturers (menarche at 13 or more years) to state they had not known what they should do at the moment they got their first period (P < .01), that they had not felt prepared to start menstruating (P < .05), and that they thought they must keep secret the fact of already having had their first period (P < .05). Concerning their emotional reactions to menarche, early maturers were the most likely to have felt scared (P < .05), worried (P < .05) and sad (P < .05) and were the least likely to have felt calm (P < .05). They were also the most likely to show current secretive attitudes towards menstruation (P < .01). Finally, late maturers showed more positive attitudes toward menstruation than their peers (P < .01).

CONCLUSIONS

These results could be useful for developing resources to help early maturing girls manage menstruation. Since these girls have limited or in some cases no time for preparation, they need special support.

Genetic and environmental effects on age at menarche, and its relationship with reproductive health in twins

INTRODUCTION:

Menarche or first menstrual period is a landmark in reproductive life span and it is the most prominent change of puberty. The timing of menarche can be under the influence of genes as well as individual environmental factors interacting with genetic factors.

OBJECTIVE:

Our study objectives were (a) to investigate the heritability of age of menarche in twins, (b) to obtain the association between age of menarche and childhood factors, and reproductive events/behavior, (c) to examine whether or not having a male co-twin affects early/late menarche.

METHODOLOGY:

A group of female-female identical (n = 108, 54 pairs), non-identical twins (n = 68, 34 pairs) and 17 females from opposite-sex twin sets were identified from twin registries of Malaysia and Iran. Genetic analysis was performed via two methods of Falconers’ formula and maximum likelihood.

RESULTS:

Heritability was found to be 66% using Falconers’ formula and 15% using univariate twin analysis. Model analysis revealed that shared environmental factors have a major contribution in determining the age of menarche (82%) followed by non-shared environment (18%).

DISCUSSION:

Result of this study is consistent with that of the literature. Timing of menarche could be under the influence of shared and non-shared environmental effects. Hirsutism was found to have a higher frequency among subjects with late menarche. There was no significant difference in age of menarche between females of opposite-sex twins and females of same-sex twins.

CONCLUSION:

It is concluded that twin models provide a powerful means of examining the total genetic contribution to age of menarche. Longitudinal studies of twins may clarify the type of environmental effects that determine the age of menarche.

Menarche and Eating Disorders

160 undergraduate women ( M age = 20.3, SD = 1.52) were assessed for depression, drug abuse, and eating disorders. The age of menarche was positively correlated with higher scores on a screening measure for eating disorders, a finding opposite to past studies for adolescent girls.

Influences on the onset and tempo of puberty in human beings and implications for adolescent psychological development

This article is part of a Special Issue "Puberty and Adolescence". Historical records reveal a secular trend toward earlier onset of puberty in both males and females, often attributed to improvements in nutrition and health status. The trend stabilized during the mid 20th century in many countries, but recent studies describe a recurrence of a decrease in age of pubertal onset. There appears to be an associated change in pubertal tempo in girls, such that girls who enter puberty earlier have a longer duration of puberty. Puberty is influenced by genetic factors but since these effects cannot change dramatically over the past century, environmental effects, including endocrine disrupting chemicals (EDCs), and perinatal conditions offer alternative etiologies. Observations that the secular trends in puberty in girls parallel the obesity epidemic provide another plausible explanation. Early puberty has implications for poor behavioral and psychosocial outcomes as well as health later in life. Irrespective of the underlying cause of the ongoing trend toward early puberty, experts in the field have debated whether these trends should lead clinicians to reconsider a lower age of normal puberty, or whether such a new definition will mask a pathologic etiology.

Puberty as a critical risk period for eating disorders: a review of human and animal studies

This article is part of a Special Issue "Puberty and Adolescence". Puberty is one of the most frequently discussed risk periods for the development of eating disorders. Prevailing theories propose environmentally mediated sources of risk arising from the psychosocial effects (e.g., increased body dissatisfaction, decreased self-esteem) of pubertal development in girls. However, recent research highlights the potential role of ovarian hormones in phenotypic and genetic risk for eating disorders during puberty. The goal of this paper is to review data from human and animal studies in support of puberty as a critical risk period for eating disorders and evaluate the evidence for hormonal contributions. Data are consistent in suggesting that both pubertal status and pubertal timing significantly impact risk for most eating disorders in girls, such that advanced pubertal development and early pubertal timing are associated with increased rates of eating disorders and their symptoms in both cross-sectional and longitudinal research. Findings in boys have been much less consistent and suggest a smaller role for puberty in risk for eating disorders in boys. Twin and animal studies indicate that at least part of the female-specific risk is due to genetic factors associated with estrogen activation at puberty. In conclusion, data thus far support a role for puberty in risk for eating disorders and highlight the need for additional human and animal studies of hormonal and genetic risk for eating disorders during puberty.

Genome wide association study of age at menarche in the Japanese population

Age at menarche (AAM) is a complex trait involving both genetic and environmental factors. To identify the genetic factors associated with AAM, we conducted a large-scale meta-analysis of genome-wide association studies using more than 15,000 Japanese female samples. Here, we identified an association between SNP (single nucleotide polymorphism) rs364663 at the LIN28B locus and AAM, with a P-value of 5.49×10(-7) and an effect size of 0.089 (year). We also evaluated 33 SNPs that were previously reported to be associated with AAM in women of European ancestry. Among them, two SNPs rs4452860 and rs7028916 in TMEM38B indicated significant association with AAM in the same directions as reported in previous studies (P = 0.0013 with an effect size of 0.051) even after Bonferroni correction for the 33 SNPs. In addition, six loci in or near CCDC85A, LOC100421670, CA10, ZNF483, ARNTL, and RXRG exhibited suggestive association with AAM (P<0.05). Our findings elucidated the impact of genetic variations on AAM in the Japanese population.

Shared genetic effects between age at menarche and disordered eating

PURPOSE

An early age at menarche is associated with disordered eating in women. However, it is unclear whether they share genetic factors. The goal of the current study was to delineate the genetic correlation between age at menarche and disordered eating.

METHODS

Participants included 427 monozygotic and 329 dizygotic 16-17-year-old female twins from the Swedish Twin Study of Child and Adolescent Development. Disordered eating was assessed with the Eating Disorder Inventory-2. Age at menarche was assessed through self-report. A bivariate correlated factors model was used to delineate the genetic correlation between age at menarche and disordered eating.

RESULTS

The analysis revealed a negative genetic correlation of -.18 in the best-fit model, indicating that the genetic factors that influence younger age at menarche are associated with increased liability for disordered eating.

CONCLUSIONS

Future research should examine possible causes for this correlation, such as the estrogen system and gene-environment interactions.

Pubertal development predicts eating behaviors in adolescence

OBJECTIVE

Early maturing girls are at increased risk for disordered eating. However, it is unclear if the association between puberty and disordered eating continues throughout pubertal development and if a similar association is exhibited in boys.

METHOD

Participants included 1340 same- and 624 opposite-sex twins from the Swedish Twin Study of Child and Adolescent Development. Pubertal development was assessed at age 13-14 with the pubertal development scale. General disordered eating, measured with the eating disorder inventory-2 (EDI) was assessed at age 16-17, and dieting and purging behaviors were assessed at both ages 16-17 and 19-20. We applied analysis of variance and logistic regression analyses to determine whether pubertal development in early-to-mid adolescence predicted eating disorder-related behaviors in late adolescence and young adulthood.

RESULTS

Pubertal development in early-to-mid adolescence was significantly associated with EDI scores and dieting in late adolescence. No significant association was observed between pubertal development and dieting and purging in young adulthood.

DISCUSSION

Complex combinations of cultural and biological influences likely converge during pubertal development increasing vulnerability to disordered eating. The impact of pubertal development on disordered eating appears to be limited to the adolescent period.

Overweight and obese teenagers: why is adolescence a critical period?

This paper discusses the critical period of adolescence and its potential role in the development and persistence of obesity. The adolescent years are characteristic of changes in body composition (location and quantity of body fat), physical fitness and decreased insulin sensitivity during puberty. This period of growth and maturation is also marked with behavioural changes in diet, physical activity, sedentary behaviour and psychological health. Physical activity and sport participation decline during adolescence especially in teenage girls, while sedentary behaviour, risk for depression and body esteem issues increase during the teenage years. These physiological and behavioural changes during adolescence warrant the attention of health practitioners to prevent the onset and continuation of obesity throughout the lifespan.

Age at menarche and digit ratio (2D:4D): relationships with body dissatisfaction, drive for thinness, and bulimia symptoms in women

This study examined the hypothesis that lower prenatal androgen exposure and earlier puberty are associated with more dysfunctional eating attitudes and behaviors. Relationships between both age at menarche (AAM) and 2D:4D (a marker of prenatal androgen exposure), and EDI-2-Body Dissatisfaction, EDI-2-Drive for Thinness, and EDI-2-Bulimia scores, were examined in women using correlations and regressions. Earlier menarche was associated with higher drive for thinness after controlling for BMI and negative affect, but only in women who were not exclusively heterosexual. Higher 2D:4D was associated with higher Bulimia and Body Dissatisfaction scores, but only in exclusively heterosexual women, and relationships disappeared when covariates were controlled. Later AAM and higher 2D:4D were unique predictors of higher Bulimia scores for exclusive heterosexuals when BMI was controlled. These findings suggest future research should examine sexual orientation as a mediator or moderator of prenatal and postnatal organizational hormonal effects on women's disordered eating attitudes and behaviors.

Perinatal environmental exposures affect mammary development, function, and cancer risk in adulthood

Puberty is an important transition that enables reproduction of mammalian species. Precocious puberty, specifically early thelarche (the appearance of breast "buds"), in girls of multiple ethnic backgrounds is a major health problem in the United States and other countries. The cause for a continued decrease in the age of breast development in girls is unknown, but environmental factors likely play a major role. Laboratory and epidemiological studies have identified several individual environmental factors that affect breast development, but further progress is needed. Current research needs include increased attention to and recording of prenatal and neonatal environmental exposures, testing of marketed chemicals for effects on the mammary gland, and understanding of the mammary gland-specific mechanisms that are altered by chemicals. Such research is required to halt the increasing trend toward puberty at earlier ages.

Pathways to early coital debut for adolescent girls: a recursive partitioning analysis

This study examined pathways to early coital debut among early to middle adolescent girls in the United States. In a two-year longitudinal study of 104 adolescent girls, recursive partitioning (RP) analyses were conducted to examine the specific factors that were related to engaging in first intercourse by the 10th grade among adolescent girls who had not yet engaged in sexual intercourse by the 8th grade. RP analyses identified subsamples of girls who had low, medium, and high likelihoods of engaging in early coital debut based on six variables (i.e., school aspirations, early physical intimacy experiences, depression, body objectification, body image, and relationship inauthenticity). For example, girls in the lowest likelihood group (3% had engaged in sex by the 10th grade) reported no prior experiences with being touched under their clothes, low body objectification, high aspirations to complete graduate education, and low depressive symptoms; girls in the highest likelihood group (75% had engaged in sex by the 10th grade) also reported no prior experiences with being touched under their clothes, but had high levels of body objectification. The implications of these analyses for the development of female adolescent sexuality, as well as for advances in quantitative methods, are discussed.

Binge eating proneness emerges during puberty in female rats: a longitudinal study

Puberty is a critical risk period for binge eating and eating disorders characterized by binge eating. Previous research focused almost entirely on psychosocial risk factors during puberty to the relative exclusion of biological influences. The current study addressed this gap by examining the emergence of binge eating during puberty in a rat model. We predicted that there would be minimal differences in binge eating proneness during pre-early puberty, but significant differences would emerge during puberty. Two independent samples of female Sprague-Dawley rats (n = 30 and n = 36) were followed longitudinally across pre-early puberty, mid-late puberty, and adulthood. Binge eating proneness was defined using the binge eating resistant (BER)/binge eating prone (BEP) model of binge eating that identifies BER and BEP rats in adulthood. Across two samples of rats, binge eating proneness emerged during puberty. Mixed linear models showed little difference in palatable food intake between BER and BEP rats during pre-early puberty, but significant group differences emerged during mid-late puberty and adulthood. Group differences could not be accounted for by changes in nonpalatable food intake or body weight. Similar to patterns in humans, individual differences in binge eating emerge during puberty in female rats. These findings provide strong confirming evidence for the importance of biological risk factors in developmental trajectories of binge eating risk across adolescence.

Risk factors, correlates, and markers in early-onset bulimia nervosa and EDNOS

OBJECTIVE

This study aimed to investigate the specific risk factors, correlates, and markers associated with the development of symptomatology of early-onset BN and subclinical BN.

METHOD

Two semi-structured interviews were used to examine symptomatology and antecedent factors of bulimic symptoms in a sample of British adolescents.

RESULTS

Adolescents with early-onset eating pathology were significantly more likely to report an earlier age of menarche than those developing the disorder at the typical age, and were found to have a different pathway of symptom development.

DISCUSSION

Increased awareness of this may help identify those particularly at risk for developing an early-onset of eating pathology.

Reported early family environment covaries with menarcheal age as a function of polymorphic variation in estrogen receptor-α

Age at menarche, a sentinel index of pubertal maturation, was examined in relation to early family relationships (conflict, cohesion) and polymorphic variation in the gene encoding estrogen receptor-α (ESR1) in a midlife sample of 455 European American women. Consistent with prior literature, women who reported being raised in families characterized by close interpersonal relationships and little conflict tended to reach menarche at a later age than participants reared in families lacking cohesion and prone to discord. Moreover, this association was moderated by ESR1 variation, such that quality of the family environment covaried positively with menarcheal age among participants homozygous for minor alleles of the two ESR1 polymorphisms studied here (rs9304799, rs2234693), but not among women of other ESR1 genotypes. In addition, (a) family relationship variables were unrelated to ESR1 variation, and (b) genotype-dependent effects of childhood environment on age at menarche could not be accounted for by personality traits elsewhere shown to explain heritable variation in reported family conflict and cohesion. These findings are consistent with theories of differential susceptibility to environmental influence, as well as the more specific hypothesis (by Belsky) that girls differ genetically in their sensitivity to rearing effects on pubertal maturation.

Early pubertal onset and its relationship with sexual risk taking, substance use and anti-social behaviour: a preliminary cross-sectional study

Background

In many countries age at pubertal onset has declined substantially. Relatively little attention has been paid to how this decline may affect adolescent behaviours such as substance use, violence and unprotected sex and consequently impact on public health.

Methods

In the UK, two opportunistic samples (aged 16-45 years), paper-based (n = 976) and online (n = 1117), examined factors associated with earlier pubertal onset and whether earlier age of onset predicted sexual risk-taking, substance use and anti-social behaviours during early adolescence.

Results

Overall, 45.6% of females reported menarche ≤ 12 years and 53.3% of males were categorised as having pubertal onset ≤ 11 years. For both sexes earlier pubertal onset was associated with poorer parental socio-economic status. Other pre-pubertal predictors of early onset were being overweight, more childhood illnesses (females) and younger age at time of survey (males). For both sexes earlier puberty predicted having drunk alcohol, been drunk, smoked and used drugs <14 years as well as having a sexual debut and unprotected sex <16 years. Males with earlier pubertal onset were more likely to report fighting and aggressive responses to emotional upset during early adolescence while females were more likely to report being bullied and having taken more time off school.

Conclusion

Results provide sufficient evidence for changes in age of pubertal onset to be further explored as a potential influence on trends in adolescent risk behaviours. Further insight into the relationship between early puberty and both obesity and socio-economic status may help inform early interventions to tackle the development of risk behaviours and health inequalities during early adolescence.

Childhood risk factors for lifetime anorexia nervosa by age 30 years in a national birth cohort

OBJECTIVE

To examine whether previously identified childhood risk factors for anorexia nervosa (AN) predict self-reported lifetime AN by age 30 years in a prospective birth cohort.

METHOD

Using data from the 1970 British Cohort Study, at birth, 5, 10, and 30 years, we examined associations between suggested childhood risk factors and self-reported lifetime AN at 30 years, adjusted for sex and socioeconomic status.

RESULTS

Anorexia nervosa was independently predicted by female sex (odds ratio [OR] 22.1), infant feeding problems (OR 2.6), maternal depressive symptoms (OR 1.8), and a history of undereating (OR 2.7). High self-esteem (OR 0.3) and higher maternal body mass index (OR 0.91) were protective.

CONCLUSIONS

Of 22 suggested risk factors for AN, only four risk and two protective factors were confirmed in this prospective cohort study. We did not identify a role for perinatal factors, parenting, childhood body mass index, childhood emotional or sleep problems, academic ability, or exercise.

A genome-wide linkage scan for age at menarche in three populations of European descent

CONTEXT

Age at menarche (AAM) is an important trait both biologically and socially, a clearly defined event in female pubertal development, and has been associated with many clinically significant phenotypes.

OBJECTIVE

The objective of the study was to identify genetic loci influencing variation in AAM in large population-based samples from three countries.

DESIGN/PARTICIPANTS

Recalled AAM data were collected from 13,697 individuals and 4,899 pseudoindependent sister-pairs from three different populations (Australia, The Netherlands, and the United Kingdom) by mailed questionnaire or interview. Genome-wide variance components linkage analysis was implemented on each sample individually and in combination.

RESULTS

The mean, sd, and heritability of AAM across the three samples was 13.1 yr, 1.5 yr, and 0.69, respectively. No loci were detected that reached genome-wide significance in the combined analysis, but a suggestive locus was detected on chromosome 12 (logarithm of the odds = 2.0). Three loci of suggestive significance were seen in the U.K. sample on chromosomes 1, 4, and 18 (logarithm of the odds = 2.4, 2.2 and 3.2, respectively).

CONCLUSIONS

There was no evidence for common highly penetrant variants influencing AAM. Linkage and association suggest that one trait locus for AAM is located on chromosome 12, but further studies are required to replicate these results.

Psychosocial development and puberty

The context of adolescent development in which puberty occurs is briefly reviewed, along with the psychosocial impact on timing of puberty, girls' perception of puberty, and the impact of puberty on relationships with parents and on psychological health. This information can be integrated into clinical practice in order to provide the best care for adolescents, but, first, access to confidential and comprehensive care must be available.

Prognosis of adolescent partial syndromes of eating disorder

BACKGROUND

Partial syndromes of eating disorder are common in adolescents but the health significance of these syndromes remains uncertain.

AIMS

To document the health and social adjustment in young adulthood of females assessed as having a partial syndrome of eating disorder in adolescence.

METHOD

A community sample of 1943 participants was tracked over 10 years in an eight-wave cohort study. A partial syndrome was defined as the fulfilment of at least two DSM-IV criteria for either anorexia or bulimia nervosa at one assessment or more between the ages of 15 years and 17 years.

RESULTS

Partial syndromes were found in 9.4% of 15- to 17-year-old female participants and 1.4% of males. There were few instances of progression of partial syndromes to fully fledged anorexia and bulimia nervosa. However, among those with partial syndromes depressive and anxiety symptoms were two to three times higher in young adulthood, substance misuse was common, and a majority of those with a partial syndrome of anorexia nervosa were still underweight in their mid-20s.

CONCLUSIONS

Given the level of subsequent psychopathology and social role impairment, there may be justification for initiating trials of preventive and early clinical intervention strategies for adolescent partial syndromes.

Public health implications of altered puberty timing

Changes in puberty timing have implications for the treatment of individual children, for the risk of later adult disease, and for chemical testing and risk assessment for the population. Children with early puberty are at a risk for accelerated skeletal maturation and short adult height, early sexual debut, potential sexual abuse, and psychosocial difficulties. Altered puberty timing is also of concern for the development of reproductive tract cancers later in life. For example, an early age of menarche is a risk factor for breast cancer. A low age at male puberty is associated with an increased risk for testicular cancer according to several, but not all, epidemiologic studies. Girls and, possibly, boys who exhibit premature adrenarche are at a higher risk for developing features of metabolic syndrome, including obesity, type 2 diabetes, and cardiovascular disease later in adulthood. Altered timing of puberty also has implications for behavioral disorders. For example, an early maturation is associated with a greater incidence of conduct and behavior disorders during adolescence. Finally, altered puberty timing is considered an adverse effect in reproductive toxicity risk assessment for chemicals. Recent US legislation has mandated improved chemical testing approaches for protecting children's health and screening for endocrine-disrupting agents, which has led to changes in the US Environmental Protection Agency's risk assessment and toxicity testing guidelines to include puberty-related assessments and to the validation of pubertal male and female rat assays for endocrine screening.

Menarche, puberty, and first sexual activities in eating-disordered patients as compared with a psychiatric and a nonpsychiatric control group

OBJECTIVE

To examine chronology and experience of menarche, puberty, and first sexual activities in eating-disordered patients as compared with a psychiatric and a nonpsychiatric control group.

METHOD

We interviewed 150 females, namely 50 patients with anorexia or bulimia nervosa (ED), 50 patients with polysubstance dependence (PSD-CO), and 50 healthy controls (HE-CO) (defined by DSM-IV) on chronology and their experience of menarche, puberty, and first sexual activities adjusted for childhood sexual abuse.

RESULTS

ED women were similar to HE-CO in age at menarche and most sexual milestones, but differed significantly from PSD-CO women, who were "early starters." Regarding their experience of menarche, pubertal body changes, and first sexual activities, however, ED women rated these variables significantly more negatively than did either of the comparison groups. These significant differences remained after adjusting for sexual abuse.

CONCLUSION

These findings suggest a negative body attitude in ED patients already at pubertal age, namely years before onset of the disorder. Prospective data are needed.

An association of early puberty with disordered eating and anxiety in a population of undergraduate women and men

Eating and anxiety disorders are more prevalent in females, increase during adolescence, and are associated with early pubertal development. This study examined whether timing of puberty onset is associated with disordered eating and anxiety in a large sample of postpubertal male and female undergraduate students. Self-report questionnaires assessed timing of puberty, disordered eating, anxiety, alcohol use, personality, and sensation seeking. Females scored significantly higher on measures of disordered eating (binge eating, dietary restraint, eating concerns, and weight and shape concerns) and anxiety (state and trait anxiety) than did males. In addition, early maturing women and men scored significantly higher on measures of disordered eating and anxiety than on time or late maturing women and men. Measures of alcohol use, sensation seeking, and personality characteristics differed in males and females but did not vary with pubertal timing. Findings suggest that early puberty is associated with disordered eating and anxiety, and this association may be due to an organizational effect of pubertal hormones. Despite important differences in body fat composition, both males and females experiencing early puberty had an increased incidence of disordered eating. The fact that early puberty was associated with increased eating and anxiety symptoms in both sexes suggests that puberty may influence these symptoms through both biological and psychosocial mechanisms.

Estimation of variance components for age at menarche in twin families

Age at menarche (AAM), time of first menstrual period, is an important developmental milestone in females. Follow-up data from 1,302 adolescent twins and their sisters were used to partition the normal variation in AAM. The proportion of censoring was 14.1%. Both a standard and a survival analysis method were used. The best fitting model from the survival analysis method was an ACE model, where 57% and 23% of the variance in AAM was explained by additive genetic and environmental effects, respectively. The best fitting model when using a standard variance decomposition method was an AE model, where 82% of the variance was explained by additive genetic effects. The lack of correspondence between the results of the two methods was an artefact of the different ascertainment of AAM reports from siblings and twins. After the removal of the sibling sample, both methods indicated that an ACE model was the most likely. Standard and survival analysis methods estimated the proportion of variance explained by additive effects to be 0.50 and 0.54, and common environmental effects to be 0.31 and 0.29, respectively. We conclude that variation in AAM can be explained by additive genetic and common environmental components.

Sexuality in the Child, Teen, and Young Adult: Concepts for the Clinician

This article discusses basic concepts of sexuality in children, adolescents, and young adults based on development stages. Sexual behavior of adolescents is a common phenomenon, leading to sexually transmitted diseases (STDs) and unwanted pregnancy. Clinicians should provide anticipatory guidance to help with healthy sexuality development while reducing negative aspects of human sexuality. Comprehensive sexuality education should be provided, with emphasis on avoiding unwanted sexual advances (including Internet dangers), bullying, pregnancy, and STDs. Clinicians can teach sexually active patients to use effective contraception and condoms for STD protection. Ensuring full immunization with the hepatitis B vaccine and the human papillomavirus vaccine also is important.