Prevalence of precocious puberty among Chinese children: a school population-based study

Effect of TSH on aromatase expression of ovarian granulosa cells in obese mice

PURPOSE

Aromatase plays an important role in ovarian development, the normal progress of the menstrual cycle, and fertility status. Elevated aromatase activity is linked to obesity. There is a bidirectional relationship between obesity and thyroid function. Few studies have investigated the relationship between TSH and ovarian aromatase in obesity. Our aim was to investigate the effect of TSH on aromatase expression of ovarian granulosa cells in obese mice.

METHODS

Female mice pups were divided into an obesity group and a control group. Obese parameters and the time of pubertal onset were recorded. At the age of 5 weeks, blood and tissues were obtained. Serum aromatase and hormone concentrations were measured using ELISA. The granulosa cells were isolated and exposed to variable concentrations (0 μM, 1 μM, 10 μM, 100 μM) of TSH. The expression of CYP19A1 mRNA and protein were assessed via RT-qPCR and western blot.

RESULTS

In female mice, body weight, Lee's obesity index, and serum levels of E2, aromatase, and TSH were significantly higher in the obesity group compared to the control group, whereas the time of pubertal onset and serum T3 and T4 concentrations were significantly lower (all P < 0.001). In granulosa cells, the expression of CYP19A1 mRNA in the obesity group was lower than that in the control group at 1 μM and 100 μM concentrations of TSH (both P < 0.001). The expression of CYP19A1 protein in the obesity group was higher than that in the control group after TSH stimulation (P = 0.014, P < 0.001, and P = 0.004, respectively). With the increase of TSH concentrations, the expression of CYP19A1 mRNA and protein in the two groups significantly increased (all P < 0.001).

CONCLUSION

Early puberty and elevated serum aromatase and TSH levels were found in obese female mice. In the granulosa cells of obese mice, TSH directly regulates aromatase expression in a dose-dependent manner.

Childhood Obesity, Hypothalamic Inflammation, and the Onset of Puberty: A Narrative Review

The onset of puberty, which is under the control of the hypothalamic-pituitary-gonadal (HPG) axis, is influenced by various factors, including obesity, which has been associated with the earlier onset of puberty. Obesity-induced hypothalamic inflammation may cause premature activation of gonadotropin-releasing hormone (GnRH) neurons, resulting in the development of precocious or early puberty. Mechanisms involving phoenixin action and hypothalamic microglial cells are implicated. Furthermore, obesity induces structural and cellular brain alterations, disrupting metabolic regulation. Imaging studies reveal neuroinflammatory changes in obese individuals, impacting pubertal timing. Magnetic resonance spectroscopy enables the assessment of the brain's neurochemical composition by measuring key metabolites, highlighting potential pathways involved in neurological changes associated with obesity. In this article, we present evidence indicating a potential association among obesity, hypothalamic inflammation, and precocious puberty.

Diagnostic Value of Single LH and LH/FSH Ratio at 60-minute after GnRHa Stimulation Test for Central Precocious Puberty

OBJECTIVES

To evaluate the diagnostic value of luteinizing hormone (LH) and LH/follicle stimulating hormone (FSH) ratio at 60 min after gonadotropin-releasing hormone analogs (GnRHa) stimulation test for central precocious puberty (CPP) in girls.

METHODS

Two hundred and fifty-seven girls, aged 3 to 7.5 y, suspected of precocious puberty at authors' hospital from April 2020 through November 2023 were enrolled in the study. The blood was taken at 0, 30, 60 min after GnRHa stimulation test, and LH and LH/FSH were detected by chemiluminescence assay. The diagnostic efficacy was analysed by Mann-Whitney U test, spearman's correlation analysis and receiver operating characteristic (ROC) analysis. The proportion of obesity was analysed by Chi-square test.

RESULTS

LH and LH/FSH at different times were statistically significantly different (P <0.05) between the CPP and non-CPP groups. Spearman's correlation analysis showed that the level of LH and LH/FSH at 60 min had the strongest consistency with the peak of LH (r = 0.9988, P <0.001) and LH/FSH (r = 0.9981, P <0.001). ROC curve analysis showed that the area under the ROC curves at 60 min of LH and LH/FSH were 0.975 and 0.997 with a cut-off value of 5.70 IU/L and 0.609, respectively.

CONCLUSIONS

The peak of LH and LH/FSH in the diagnosis of CPP can be determined by LH and LH/FSH at 60 min after the triptorelin acetate is injected. This will reduce the number of blood draws required compared with the traditional stimulation test, which is more effective and acceptable for children.

Joint association of overweight/obesity, high electronic screen time, and low physical activity time with early pubertal development in girls: a case-control study

To examine the joint association of electronic screen time (EST), moderate-to-vigorous physical activity time (MVPA) and overweight/obesity with early pubertal development (EPD) in girls. A case-control study of 177 EPD girls and 354 girls with normal pubertal development was conducted between October 2019 and August 2022. Overweight/obesity was defined as body mass index ≥ 85th percentiles for age and sex. We found a non-significant increase of EPD risk among girls with high EST alone [OR: 2.75 (0.65-11.58)] or low MVPA alone [OR: 2.54 (0.74-8.69)], but a significant increase of EPD risk among girls with overweight/obesity alone [OR: 4.91 (1.01-23.92)], compared to girls without any of the three risk factors (low MVPA, high EST and overweight/obesity). Girls with any two of the three risk factors faced increased risk of EPD, and girls with all three risk factors faced the highest risk of EPD [OR and 95% CI: 26.10 (6.40-106.45)]. Being overweight/obesity might be more important than having low MVPA or high EST as a correlate of EPD compared to girls without any of the three risk factors, but the co-presence of low MVPA, high EST and overweight/obesity would largely increase the risk of EPD in girls.

Association of obesity and menarche SNPs and interaction with environmental factors on precocious puberty

BACKGROUND

Obesity is an important cause for the precocious or early puberty. However, the association between obesity-related loci and the risk of precocious puberty as well as the effect of gene-environment interaction are unclear, especially in the Chinese children population.

METHODS

This was a case-control study using baseline data from two cohorts and hospital cases in China. 15 SNPs loci and several environmental factors were included in the analysis of 1201 participants. Chi-square test and logistic regression were used to analyze the association between SNPs and precocious puberty. Additionally, exploratory factor analysis was conducted on 13 environmental variables, and then to explore their interaction with genes on precocious puberty.

RESULTS

The effect allele C of rs571312, and G of rs12970134 MC4R were associated with precocious puberty in girls with obesity. Regarding the gene-environment interaction, we found that when girls were in the high socioeconomic status, the rs571312 (OR: 3.996; 95% CI: 1.694-9.423) and rs12970134 (OR: 3.529; 95% CI: 1.452-8.573) risk genotypes had a greater effect on precocious puberty.

CONCLUSIONS

The obesity risk gene polymorphisms MC4R rs571312 and rs12970134 were associated with precocious puberty in Chinese girls with obesity, and girls with risk genotypes and high socioeconomic status should be given extra attention.

IMPACT

This is the first study that identified the association between rs571312 and rs12970134 of MC4R gene and precocious puberty in Chinese children. We found that when girls were in the high socioeconomic status, the risk genotypes of rs571312 and rs12970134 had a greater effect on precocious puberty. The results of this study have great public health implications. It is recommended that girls who are in high socioeconomic status and have a high genetic risk for early sexual maturity should closely monitor their pubertal development and consider early intervention strategies.

Diagnostic value of adenohypophyseal MRI features in female children with precocious puberty

AIM

To evaluate the diagnostic value of adenohypophyseal magnetic resonance imaging (MRI) features for precocious puberty (PP) in female children and also to establish a non-invasive diagnostic approach in clinics.

MATERIALS AND METHODS

A total of 126 female children (37, 57, and 32 female children clinically diagnosed with central PP [CPP], incomplete PP [IPP], and controls, respectively) were enrolled in this study. Data were collected and analysed using analysis of variance. Pearson correlation and stepwise multivariate linear regression analysis were used to examine the association and build prediction models. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic efficacy.

RESULTS

The values of adenohypophysis volume (aPV), adenohypophysis height (aPH), and signal-intensity ratio (SIR), height, weight, and seven laboratory testing characteristics were correlated closely with the activation status of the hypothalamic-pituitary-gonad axis in the different groups (all p<0.05). Model 1 including aPV, weight, and aPH and Model 2 including SIR, aPV, and height were built to obtain predicted luteinising hormone (LH; R2 = 0.271) and LH/follicle stimulating hormone (FSH; R2 = 0.311). ROC analysis showed the predicted LH, predicted LH/FSH, and aPV were the top 3 best predictors in distinguishing CPP from controls (AUC = 0.969, 0.949, and 0.938) while predicted LH/FSH was the best predictor in distinguishing CPP from IPP and controls (AUC = 0.829 and 0.828).

CONCLUSION

The adenohypophysis volume itself and the prediction models including main adenohypophyseal MRI features increased diagnostic efficiency for PP and offered a non-invasive and credible diagnostic method.

Multi-omic analysis of precocious puberty girls: pathway changes and metabolite validation

Objective

Precocious puberty (PP) is a prevalent endocrine disorder affecting the physical and mental wellbeing of children. Identifying the triggering factors of PP has become a central issue. This study seeks to investigate the metabolomic and transcriptomic alterations in PP.

Material and methods

First, 37 school-aged girls diagnosed with PP and 25 age-matched prepubertal control girls were recruited, and the fecal samples were collected for non-targeted metabolomic analysis to screen for differentially expressed metabolites (DEMs). Subsequently, an animal model of PP was constructed by danazol administration to neonatal female rats, and both fecal non-targeted metabolomics and serum next-generation transcriptomic sequencing were performed to screen DEMs and differentially expressed genes (DEGs) in PP. Moreover, the DEM co-existing in clinical and animal models was administrated to PP rats to explore the role of the target metabolite in PP.

Results

A total of 24 DEMs in PP clinical samples and 180 DEMs and 425 DEGs in PP animal samples were identified. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that these DEMs and DEGs were enriched in disease-associated pathways, including fatty acid synthesis, glycerolipid metabolism, pyrimidine metabolism, steroid hormone biosynthesis, progesterone-mediated oocyte maturation, and gonadotropin-releasing hormone (GnRH) signaling pathway, forming a tight DEM-DEG pathway regulatory network. Further DEM validation demonstrated that thymine supplementation delayed the opening of the vagina and development of PP in model rats.

Conclusion

This study reveals that the metabolomic and transcriptomic changes, along with enriched pathways, are implicated in PP based on clinical and animal analyses. The findings may provide new strategies and research avenues for PP treatment.

Effects of the COVID-19 pandemic on the incidence of central precocious puberty; a narrative review

Central precocious puberty (CPP) is the premature activation of the hypothalamus-pituitary-gonadal axis, resulting in the early development of secondary sexual characteristics. CPP classically occurs before the age of 8 years in girls and 9 years in boys. The aetiology of this precocious onset of puberty is governed by complex mechanistic interactions between genetic and environmental factors. The rates of CPP have been documented to have been rising before the COVID-19 pandemic; despite this, the incidence of CPP has increased exponentially since the start of the pandemic. There are multiple theories potentially explaining this change in incidence of CPP over COVID-19. These include the direct effect of SARS-coV-2 infection, increasing body mass index of adolescents over sequential lockdowns, changes in sleep patterns, increased use of electronic devices and levels of stress, and additionally potential earlier detection of signs of CPP by parents and carers. Whilst there is evidence from observational cohorts, case studies and animal models for each of these factors, it is difficult to definitively prove which has had the greatest impact due to the mainly retrospective nature of the human research that has been conducted. Moreover, studies set in diverse settings with varying population make comparison complex. Additionally, each country responded differently to the COVID-19 pandemic and the lockdowns varied between locations, hence the effect of lockdown was not equal or universal. Despite this, similar trends have been identified, with various lifestyle changes that occurred over the pandemic being potentially influential factors on the development of CPP.

Prediction of body mass index and skeletal maturity for early menarche risk at menarche onset: a cross-sectional study of Chinese girls

BACKGROUND

This study aimed to assess the predictive value of body mass index (BMI) and skeletal maturity for the occurrence of early menarche in Chinese girls.

METHODS

A cross-sectional analysis was conducted on 785 girls aged 8.1-14.6 years who visited our hospital within 3 months of menarche onset. Early menarche was defined as menarche age (MA) <10 years. Skeletal maturity was classified based on the difference between bone age (BA) and chronological age (CA), termed BA-CA; advanced BA was defined as BA-CA>2 years.

RESULTS

The average MA was 10.7 (SD: 1.1) years, with a prevalence of early menarche of 23.3%. BA exhibited relative stability compared with MA, with an average of 12.8 (SD: 0.5) years at menarche onset. At menarche onset, the average height, weight and BMI were 149.1 (SD: 5.1) cm, 43.3 (SD: 7.2) kg and 19.4 (SD: 2.8) kg/m², respectively. Logistic regression analyses indicated that every 1-year increment in BA-CA was independently associated with a 18.90-fold higher risk of early menarche (95% CI 11.77 to 30.32), respectively, and remained statistically significant even after adjusting for height or mid-parental height. Furthermore, the prediction of BA-CA for early menarche demonstrated a dose-dependent pattern across BMI categories, with the greatest risk observed in normal-weight girls, the lowest risk in obese girls and an intermediate risk in overweight girls at the same degree of BA advancement.

CONCLUSIONS

Our findings provide evidence supporting the significant contributions of BMI and skeletal maturity in predicting early menarche among Chinese girls at menarche onset. Additionally, the results suggest a dose-dependent relationship between skeletal maturity and BMI categories, with normal-weight girls displaying a higher risk of early menarche compared to overweight and obese girls with the same degree of BA advancement.

Polymorphism rs5780218, rs12998 and rs10158616 in KISS1 gene among the Hubei province Chinese girls with the central precocious puberty

PURPOSE

Central precocious puberty (CPP) results from early activation of the hypothalamic-pituitary-gonadal (HPG) axis. To elucidate the molecular genetic basis of CPP, we here investigated the effects of polymorphism rs5780218, rs12998 and rs10158616 in KISS1 gene on CPP susceptibility.

METHODS

The three KISS1 gene polymorphisms were genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and Sanger sequencing in 422 healthy Hubei Chinese girls and 384 Hubei Chinese girls with CPP.

RESULTS

Single-locus analysis demonstrated that rs5780218 and rs12998 were significantly associated with CPP susceptibility in Hubei Chinese girls. Haplotype analysis exhibited that the AGG carrying the risk allele A of rs5780218 and the -GG carrying the protective allele - of rs5780218 were associated with increased and decreased CPP susceptibility in Hubei Chinese girls, respectively. The following meta-analysis confirmed the contribution of rs5780218 and rs12998 on CPP susceptibility in Chinese girls.

CONCLUSIONS

rs5780218 and rs12998 in the KISS1 gene may participate in genetic susceptibility to CPP in Chinese girls, and the KISS1 gene rs5780218 may serve as a genetic biomarker of CPP. However, the present findings should be validated in future studies with larger sample sizes in other ethnic populations.

Not Only Metabolic Complications of Childhood Obesity

The increasing incidence of obesity in the pediatric population requires attention to its serious complications. It turns out that in addition to typical, well-known metabolic complications, obesity as a systemic disease carries the risk of equally serious, although less obvious, non-metabolic complications, such as cardiovascular diseases, polycystic ovary syndrome, chronic kidney disease, asthma, thyroid dysfunction, immunologic and dermatologic conditions, and mental health problems. They can affect almost all systems of the young body and also leave their mark in adulthood. In addition, obesity also contributes to the exacerbation of existing childhood diseases. As a result, children suffering from obesity may have a reduced quality of life, both physically and mentally, and their life expectancy may be shortened. It also turns out that, in the case of obese pregnant girls, the complications of obesity may also affect their unborn children. Therefore, it is extremely important to take all necessary actions to prevent the growing epidemic of obesity in the pediatric population, as well as to treat existing complications of obesity and detect them at an early stage. In summary, physicians treating a child with a systemic disease such as obesity must adopt a holistic approach to treatment.

Postnatal feeding with high-fat combined with high-glucose diet induces precocious puberty in Sprague‒Dawley rat pups

With economic development and overnutrition, including high-fat diets (HFD) and high-glucose diets (HGD), the incidence of obesity in children is increasing, and thus, the incidence of precocious puberty is increasing. Therefore, it is of great importance to construct a suitable animal model of overnutrition-induced precocious puberty for further in-depth study. Here, we fed a HFD, HGD, or HFD combined with a HGD to pups after P-21 weaning, while weaned pups fed a normal diet served as the control group. The results showed that HFD combined with a HGD increased the body weight (BW) of weaned rat pups. In addition, a HFD, HGD, and HFD combined with a HGD lowered the age at which vaginal opening occurred and accelerated the vaginal cell cycle. Furthermore, a HFD combined with a HGD increased the weight of the uterus and ovaries of weaned rat pups. Additionally, a HFD combined with a HGD promoted the development of reproductive organs in weaned female rat pups. Ultimately, a HFD combined with a HGD was found to elevate the serum levels of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), follicle stimulating hormone (FSH), leptin, adiponectin, and oestradiol (E2) and increase hypothalamic GnRH, Kiss-1, and GPR54 expression levels in weaned female rat pups. The current study found that overnutrition, such as that through a HFD combined with HGD, could induce precocious puberty in weaned female rat pups. In addition, a rat model of overnutrition-induced precocious puberty was established.

Efficacy and mechanism of nourishing yin and purging fire therapy for central precocious puberty based on meta-analysis and network pharmacology

BACKGROUND

Central precocious puberty (CPP) is due to the early activation of the hypothalamus-pituitary-gonadal axis, and its incidence is on the rise. A number of studies have shown that nourishing yin and purging fire (NYPF) therapy can be beneficial for CPP. Therefore, we conducted this review to investigate the efficacy, safety, and mechanism of NYPF therapy for CPP.

METHODS

Electronic databases including PubMed, the Cochrane Library, Web of Science, EMBASE, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Wan-fang Database, and China Scientific Technical Journals Database and 2 platforms including Clinical Trials and Chinese Clinical Trial Registry were searched for randomized controlled trials of NYPF therapy for CPP. A meta-analysis was conducted using RevMan 5.3 and Stata 17.0 software. The core herb pair of NYPF was identified by data mining using IBM SPSS Modeler 18.0 software. The active ingredients and targets of the core herb pair were obtained through the TCMSP database. The main targets of CPP were acquired form the GeneCards, Disgenet and TTD databases. A protein-protein interaction network was carried out to select the core genes by using STRING platform and Cytoscape 3.7.2 software. Metascape platform was used to conduct gene ontology (GO) and KEGG enrichment analysis. The results were verified utilizing molecular docking.

RESULTS

A total of 23 studies were included. Meta-analysis shows the NYPF therapy could significantly improve the clinical efficacy rate and secondary sexual indicators (uterine volume, ovarian volume, breast nucleus diameter, follicular diameter), reduce TCM syndrome scores and serum sex hormone (FSH, LH, E2), and slow down bone age maturation compared to GnRHa therapy group. In addition, NYPF therapy was safe and has no obvious adverse events. Data mining revealed that the core herb pair of NYPF was "Anemarrhenae Rhizoma (Zhimu) - Phellodendri Chinensis Cortex (Huangbai)." Network pharmacology predicted that quercetin, kaempferol, beta-sitosterol, etc were the key components of Zhimu-Huangbai for treating CPP. The core targets were TP53, JUN, AKT1, ESR1, TNF, IL6, CCND1, MAPK1, BCL2, EGFR, IL1B, and PTGS2. They played a pivotal role in modulating multiple signaling pathways, such as Endocrine resistance, MAPK signaling pathway, and PI3K-Akt signaling pathway.

CONCLUSION

This article revealed that NYPF therapy is effective and safe against CPP. The mechanism of the core herb pair of NYPF therapy for CPP through muti-components, muti-targets and muti-pathways.

Trends of obesity and overweight among children and adolescents in China

BACKGROUND

Recent decades have shown a rapid increase in the prevalence of overweight and obesity among Chinese children based on several national surveys. Restrictions due to the coronavirus disease 2019 outbreak have worsened its epidemiology. This review updates the trends in the prevalence of overweight and obesity among Chinese children and adolescents and analyzes the underlying reasons to provide evidence for better policy making.

METHODS

Studies published in English and Chinese were retrieved from PubMed, Google Scholar, China National Knowledge Infrastructure and Wanfang.

RESULTS

The prevalence of overweight and obesity has been increasing for decades and varies with age, sex and geography but is more pronounced in primary school students. The increase in obesity in boys appeared to be slower, whereas that in girls showed a declining trend. The northern areas of China have persistently maintained the highest levels of obesity with a stable trend in recent years. Meanwhile, the prevalence in eastern regions has dramatically increased. Notably, the overall prevalence of obesity in children has shown a stabilizing trend in recent years. However, the occurrence of obesity-related metabolic diseases increased. The effect of migrants floating into east-coast cities should not be neglected.

CONCLUSIONS

The high prevalence of overweight and obesity among Chinese children and adolescents persists but with varying patterns. Obesity-related metabolic diseases occur more frequently despite a stable trend of obesity. Multiple factors are responsible for the changing prevalence. Thus, comprehensive and flexible policies are needed to effectively manage and prevent the burden of obesity and its related complications.

Efficacy and Safety of Triptorelin 3-Month Formulation in Chinese Children with Central Precocious Puberty: A Phase 3, Open-Label, Single-Arm Study

INTRODUCTION

Triptorelin is available as 1- and 3-month prolonged-release (PR) formulations; at the time of the study, only the former was approved for central precocious puberty (CPP) in China. This study assessed the efficacy and safety of the triptorelin 3-month PR formulation in Chinese children with CPP.

METHODS

In this 12-month, prospective, open-label, multicentre, single-arm study (NCT04736602), Chinese children (mean age [standard deviation (SD)], 7.6 ± 0.8 years) with CPP received triptorelin pamoate 15 mg on day 1 and at months 3, 6 and 9. The primary endpoint was the proportion with luteinizing hormone (LH) suppression (stimulated peak LH ≤ 3 IU/L after gonadotropin-releasing hormone [GnRH] stimulation) at month 3. Secondary endpoints included changes from baseline in hormone levels and clinical parameters, as well as safety assessments.

RESULTS

Overall, 32 children were enrolled, including three boys. LH suppression to prepubertal levels (≤ 3 IU/L) after GnRH stimulation was observed in 100%, 93.5% and 93.5% of participants at months 3, 6 and 12, respectively. Basal and peak LH and follicle-stimulating hormone levels were substantially suppressed at months 3, 6 and 12, and most participants showed sex hormone suppression. At months 6 and 12 respectively 92.9% and 89.3% of girls had stable breast development, and all boys had stable genital development. There was a decrease in mean growth velocity from baseline (8.96 cm/year) to months 3, 6 and 12 (8.07, 5.24 and 6.94 cm/year, respectively). The mean difference between bone and chronological age decreased from baseline (2.85 years) to month 12 (2.39 years). In girls, uterine length was stable or reduced at month 12; in boys, testicular volume was reduced. Triptorelin was well tolerated.

CONCLUSION

The triptorelin 3-month PR formulation demonstrated similar efficacy to that previously reported in non-Chinese patients with CPP and had an acceptable safety profile. This supports triptorelin 3-month PR as a viable option for Chinese children with CPP.

Analysis of risk factors of precocious puberty in children

BACKGROUND

The purpose of this study is to explore the related factors of precocious puberty in children.

METHODS

1239 children who underwent physical examination in our hospital from January 2020 to December 2022 were analyzed, including 198 precocious children and 1041 normal children. According to the age of 198 precocious children and 1041 normal children, 205 normal children were selected, and the remaining 836 normal children were excluded. They were divided into precocious group and normal group. The general data of the two groups were recorded. Logistic regression was used to analyze the influencing factors of precocious puberty in children.

RESULTS

There were statistically significant differences (P < 0.05) between the two groups in sex, bone age, daily exercise time, E2, FSH, LH, leptin, mother's menarche time, living environment, consumption of nutritional supplements, consumption of foods containing pigments and preservatives, consumption of high-protein foods, and sleeping time. The multifactor logistic regression analysis shows that the risk factors of children's precocious puberty included gender (female), bone age (> 10 years old), and daily exercise time (< 0.9 h), E2 (≥ 66.00pmol/L), FSH (≥ 6.00U/L), LH (≥ 3.50U/L), leptin (≥ 8.00 µ G/L), mother's menarche time (< 12 years old), living environment (chemical industry zone), consumption of nutritional supplements (often), consumption of high-protein food (often), and sleep time (< 10 h).

CONCLUSION

In conclusion, children's gender, bone age, exercise habits, E2, FSH, LH, leptin, mother's menarche time, living environment, eating habits, sleep time and other factors are closely related to precocious puberty in children. Reminding parents to actively prevent related factors in clinical work is helpful to prevent the occurrence of precocious puberty in children.

Association between precocious puberty and obesity risk in children: a systematic review and meta-analysis

Objectives

The aim of this study was to evaluate the potential association between early onset puberty and the risk of different forms of obesity in children.

Methods

The databases PubMed, EMBASE, Web of Science and Cochrane Library were systematically searched for relevant studies. The odds ratio (OR) and 95% confidence interval (CI) of obesity in precocious puberty were calculated using Stata software 14.0. A fixed-effects model was used if P > 0.1 and I2 ≤ 50%. Otherwise, a random-effects model was used. Publication bias was assessed using funnel plots and Egger's test.

Result

The pooling analysis showed that precocious puberty in girls was associated with a higher risk of obesity (OR = 1.98; 95% CI: 1.76-2.24; I2 = 0.00%, P < 0.001). Girls with a history of precocious puberty were found to have an increased risk of general obesity (OR = 2.03; 95% CI: 1.62-2.55; I2 = 22.2%, P < 0.001), central obesity (OR = 1.96; 95% CI: 1.70-2.26; I2 = 0.00%, P < 0.001), and overweight (OR = 2.03; 95% CI: 1.68-2.46; I2 = 5.1%, P < 0.001). The pooled analysis showed that precocious puberty in boys was not associated with an increased risk of obesity (OR = 1.14; 95% CI: 0.86-1.51; I2 = 50.6%, P = 0.369). In boys, the occurrence of precocious puberty was not associated with an elevated risk of general obesity (OR = 0.96; 95% CI: 0.40-2.27; I2 = 79.6%, P = 0.922), central obesity (OR = 1.17; 95% CI: 0.96-1.43; I2 = 0.00%, P = 0.125), or overweight (OR = 1.03; 95% CI: 0.56-1.88; I2 = 74.4%, P = 0.930).

Conclusion

This meta-analysis suggests that the onset of puberty at an early age in girls is associated with an increased risk of obesity, however precocious puberty in boy was not associated with an increased risk of obesity. These findings highlight that precocious puberty should be considered an independent risk factor for obesity in girls.

Systematic Review Registration

CRD42023404479.

Prosopagnosia (face blindness) and child health during the COVID-19 pandemic

Prosopagnosia or 'face blindness' is the inability to recognise people's faces. There are two types: congenital or developmental prosopagnosia, which is the most common, and acquired prosopagnosia, which may occur secondary to brain tumours, stroke or other brain disorders. The authors of this article explored if mask wearing as a result of the restrictions imposed by the coronavirus disease 2019 (COVID-19) pandemic may affect social and developmental outcomes in children, including the development of prosopagnosia. Limited research on this topic is available and, although some relevant publications were found, no definitive evidence of mask-induced prosopagnosia in children was identified. However, nurses should be aware of this issue and discuss coping strategies to support children with the condition. Longitudinal studies on outcomes in children from different age groups who grew up during the COVID-19 pandemic will provide further insight.

Persistent high exposure to exogenous phthalates and endogenous sex hormones associated with early pubertal onset among children: A 3.5-year longitudinal cohort study in China

BACKGROUND

Early onset of puberty could have significant impacts on childhood health, but the extent to which it was affected by phthalate esters (PAEs) and sex hormone disruption was not understood. The aim of this study is to investigate the associations between exposure to PAEs and sex hormone disruption and early onset of puberty in children.

METHODS

A longitudinal cohort study was conducted in China from May 2017 to Oct 2020, involving 740 children during consecutive visits. The onset of puberty was evaluated using Tanner definition, and early puberty was defined as an onset age less than the first 25 %, with cut-offs of 10.33 and 8.97 years for boys and girls, respectively. Serum testosterone (TT), estradiol (E₂) and urinary PAE metabolites were measured during three visits. Generalized linear models were used to explore the associations between PAE and sex hormones with the age of puberty onset, while log-binomial regressions were applied to assess the associations of persistent exposure to PAEs and sex hormones with early pubertal onset.

RESULTS

Approximately 86.0 % of boys and 90.2 % of girls completed puberty onset from pre-puberty, and more than 95 % of participants had PAE concentrations higher than the limit of detection. Boys showed higher exposure to PAE pollutants and higher TT levels. Persistent exposure to PAEs was positively associated with early pubertal onset in girls (ARR = 1.97, 95 %CI = 1.12, 3.46). Moreover, persistent exposure to PAEs and E₂ had synergistic associations with early pubertal onset in both boys (ARR = 4.77, 95 %CI = 1.06, 21.54) and girls (ARR = 7.07, 95 %CI = 1.51, 33.10). However, PAEs and TT had antagonistic associations only in boys (ARR = 0.44, 95 %CI = 0.07, 2.58).

CONCLUSION

Long-term exposure to PAEs might increase the risk of early pubertal onset, and it appears to work in synergy with E₂, while in antagonism with TT in boys' early pubertal onset. Reducing PAEs exposure might promote pubertal health.

Associations of Obesity With Growth and Puberty in Children: A Cross-Sectional Study in Fuzhou, China

Objectives: To investigate the associations of obesity with growth and puberty in children. Methods: From November 2017 to December 2019, height, weight, and Tanner stages of 26,879 children aged 3-18 years in Fuzhou, China were assessed. Results: The obese group was significantly taller than the non-obese group after age 4 years for both genders, yet there was no significant difference in height between obese and non-obese group after 15.5 years old for boys and 12.5 years old for girls. The inflection points of significant growth deceleration in obese and non-obese groups were 14.4 and 14.6 years old for boys, and 11.8 and 12.8 years old for girls, respectively. The proportions of testicular development in boys with obesity and non-obesity were 7.96% and 5.08% at 8.5-8.9 years old, respectively, while the proportions of breast development in girls were 17.19% and 3.22% at age 7.5-7.9 years old, respectively. Conclusion: Children with obesity were taller in early childhood, earlier onset of puberty and earlier cessation of growth than children with non-obesity of the same age. However, there was sex dimorphism on the effect of obesity on the incidence of precocious puberty.

The effect of environmental factors on precocious puberty in children: a case-control study

BACKGROUND

Recently the prevalence of precocious puberty development is increasing among Chinese children. Proper understanding of the risk factors for precocious puberty in children is pivotal as could help to improve children's health. This study aims to evaluate the effect of environmental factors on precocious puberty in children.

METHODS

We matched the cases and controls by age at the ratio of 1:1 (201 cases and 201 controls) for girls and 1:4 (24 cases and 96 controls) for boys. We used conditional logistic regression to explore the effect of environmental factors on precocious puberty, and a random forest model to identify the most important risk factor.

RESULTS

In the multivariate regression, cesarean section (OR = 1.99, 95% CI: 1.05, 3.76), child body mass index [BMI] (OR = 1.25, 95% CI: 1.10, 1.43), maternal BMI (OR = 1.13, 95%CI: 1.01, 1.26), and exposure to secondhand smoke several times a month but less than once a week (OR = 4.09, 95%CI: 1.79,9.35), and almost every day (OR = 6.48, 95% CI: 2.14, 19.56) were risk factors for precocious puberty in girls. While maternal height (OR = 0.82, 95% CI: 0.75, 0.88), paternal height (OR = 0.91, 95% CI: 0.85, 0.98), bedtime at night (OR = 0.30, 95% CI: 0.17, 0.51), and night sleep (OR = 0.43, 95% CI: 0.21, 0.86) were protective factors. In boys, only exposure to secondhand smoke several times a month but less than once a week (OR = 7.94, 95% CI: 1.25, 50.33) was a risk factor for precocious puberty. In the random forest model, Child BMI was the most important risk factor for precocious puberty in girls.

CONCLUSIONS

Our findings suggest that environmental factors were associated with precocious puberty in children, particularly in girls.

Serum metabolomic analysis reveals key metabolites in drug treatment of central precocious puberty in female children

Precocious puberty (PP) is a common condition among children. According to the pathogenesis and clinical manifestations, PP can be divided into central precocious puberty (CPP, gonadotropin dependent), peripheral precocious puberty (PPP, gonadotropin independent), and incomplete precocious puberty (IPP). Identification of the variations in key metabolites involved in CPP and their underlying biological mechanisms has increased the understanding of the pathological processes of this condition. However, little is known about the role of metabolite variations in the drug treatment of CPP. Moreover, it remains unclear whether the understanding of the crucial metabolites and pathways can help predict disease progression after pharmacological therapy of CPP. In this study, systematic metabolomic analysis was used to examine three groups, namely, healthy control (group N, 30 healthy female children), CPP (group S, 31 female children with CPP), and treatment (group R, 29 female children) groups. A total of 14 pathways (the top two pathways were aminoacyl-tRNA biosynthesis and phenylalanine, tyrosine, and tryptophan biosynthesis) were significantly enriched in children with CPP. In addition, two short peptides (His-Arg-Lys-Glu and Lys-Met-His) were found to play a significant role in CPP. Various metabolites associated with different pathways including amino acids, PE [19:1(9Z)0:0], tumonoic acid I, palmitic amide, and linoleic acid-biotin were investigated in the serum of children in all groups. A total of 45 metabolites were found to interact with a chemical drug [a gonadotropin-releasing hormone (GnRH) analog] and a traditional Chinese medicinal formula (DBYW). This study helps to understand metabolic variations in CPP after drug therapy, and further investigation may help develop individualized treatment approaches for CPP in clinical practice.

Effects of half-dose spiomet treatment in girls with early puberty and accelerated bone maturation: a multicenter, randomized, placebo-controlled study protocol

BACKGROUND

A "mismatch" sequence of less prenatal weight gain and more postnatal weight gain may lead to ectopic lipid accumulation, and trigger the development of early adrenarche/pubarche and the activation of the gonadotropic axis resulting in early puberty and ending up in full-blown adolescent polycystic ovary syndrome (PCOS). In the present study, we assess whether a low-dose combination of generics that collectively reduce ectopic fat through different pathways can slow down the accelerated maturation in "mismatch" girls with early puberty.

METHODS

Randomized, placebo-controlled, multicenter, phase 2a, study in 64 girls [age, 8.0-9.3 years; birthweight (BW) for gestational age in lower tertile (-1.96< Z-score <-0.44), body mass index (BMI) in upper tertile (+0.44< Z-score < +1.96) and early progressive puberty (Tanner B2 at 7.7-9.0 years)]. Pharmacological intervention will be with a half-dose version of SPIOMET (mini-spiomet), a combination that reverts the PCOS phenotype in "mismatch" adolescents; mini-spiomet will contain spironolactone (25 mg/day, to raise brown adipose tissue activity), pioglitazone (3.75 mg/day, to raise adiponectin and insulin sensitivity), and metformin (425 mg/day, to raise AMPK activity and GDF15). Recruitment: 1 year; double-blind treatment: 1 year; open follow-up: 1 year; analyses and reporting: 1 year.

INTERVENTIONS

randomization (1:1) for placebo vs mini-spiomet.

PRIMARY OUTCOME

annualized bone age advancement (0-1 year) by BoneXpert; secondary outcomes: insulin, IGF-I, high-molecular-weight adiponectin (HMW-adip), sex hormone binding globulin (SHBG), ultra-sensitive C-reactive protein (usCRP), androgens, luteinizing hormone (LH), follicle-stimulating hormone (FSH), oestradiol, growth-and-differentiation factor 15 (GDF15), C-X-C motif chemokine ligand-14 (CXCL14), safety parameters, and quantification of hepato-visceral fat.

DISCUSSION

The present study, if successful, may provide a first proof of the concept that the rapid maturation of girls with an upward mismatch between pre- and post-natal weight gain can be slowed down with a fixed low-dose combination of old and safe generics jointly targeting a reduction of ectopic fat without necessarily lowering body weight.

TRIAL REGISTRATION

EudraCT 2021-006766-21. Registered on May 30, 2022.

Nonclassic Adrenal Hyperplasia (NCAH) due to 21-hydroxylase deficiency: A cohort of 78 patients

Diagnosis of nonclassic adrenal hyperplasia (NCAH) due to 21-hydroxylase deficiency (21-OHD) may be challenging due to its occult manifestations. To characterize clinical and molecular features of NCAH patients due to 21-hydroxylase deficiency, we retrospectively included 78 NCAH patients. Their phenotype and genotype were presented and compared. The transcription activities of novel CYP21A2 promoter variants were investigated using a dual-reporter luciferase assay system. This cohort included 53 females (68 %) and 25 males (32 %). The median of onset age was 13 years old (female: 13 range from 7 to 38; male: 11 range from 6 to 71). Menstrual cycle disorder was the most common complaint in females (62 %, n = 33) and for males, it was adrenal incidentalomas (52 %, n = 13). A total of 17 (22 %) patients complained of infertility. The most frequently variant was p.Ile173Asn (20 %, n = 31). Importantly, five variants in the promoter region including - 103/- 126 and - 196/- 296 were found in 21 (27 %) patients. Patients with promoter variants showed older onset age and less impaired hormone levels of 17-hydroxyprogesterone, ACTH, progesterone, and androstenedione. Compared with the wild-type promoter, the basic transcription activity of - 103/- 126 and - 196/- 296 promoter variants were reduced by 57% and 25%, respectively. Therefore, females with menstrual cycle disorders or infertility and males with adrenal incidentaloma should be considered of NCAH due to 21-OHD. When genotyping patients with NCAH, the promoter region of the CYP21A2 gene should be also investigated.

Precocious puberty under stressful conditions: new understanding and insights from the lessons learnt from international adoptions and the COVID-19 pandemic

Neuro-biological variations in the timing of sexual maturation within a species are part of an evolved strategy that depend on internal and external environmental conditions. An increased incidence of central precocious puberty (CPP) has been described in both adopted and "covid-19 pandemic" children. Until recently, it was hypothesised that the triggers for CPP in internationally adopted children were likely to be better nutrition, greater environmental stability, and improved psychological wellbeing. However, following data collected during and after the coronavirus (COVID-19) global pandemic, other possibilities must be considered. In a society with high levels of child wellbeing, the threat to life presented by an unknown and potentially serious disease and the stressful environment created by lockdowns and other public health measures could trigger earlier pubertal maturation as an evolutionary response to favour early reproduction. The main driver for increased rates of precocious and rapidly progressive puberty during the pandemic could have been the environment of "fear and stress" in schools and households. In many children, CPP may have been triggered by the psychological effects of living without normal social contact, using PPE, being near adults concerned about financial and other issues and the fear of getting ill. The features and time of progression of CPP in children during the pandemic are similar to those observed in adopted children. This review considers the mechanisms regulating puberty with a focus on neurobiological and evolutionary mechanisms, and analyses precocious puberty both during the pandemic and in internationally adopted children searching for common yet unconsidered factors in an attempt to identify the factors which may have acted as triggers. In particular, we focus on stress as a potential factor in the early activation of the hypothalamic-pituitary-gonadal axis and its correlation with rapid sexual maturation.

Effects of Ambient Air Pollution on Precocious Puberty: A Case-Crossover Analysis in Nanjing, China

BACKGROUND

Ambient air pollution is closely related to a variety of health outcomes. Few studies have focused on the correlations between air pollution exposure and children's sexual development. In this study, we investigated the potential effects of exposure to air pollution on precocious puberty among children using real-world evidence.

METHODS

We conducted a case-crossover study (n = 2201) to investigate the effect of ambient air pollution exposure on precocious puberty from January 2016 to December 2021. Average exposure levels of PM_2.5, PM₁₀, SO₂, NO₂, CO, and O₃ before diagnosis were calculated by using the inverse distance weighting (IDW) method. Distributed lag nonlinear model (DLNM) was used to assess the effect of air pollutants exposure on precocious puberty.

RESULTS

The mean age of the children who were diagnosed with precocious puberty was 7.47 ± 1.24 years. The average concentration of PM_2.5 and PM₁₀ were 38.81 ± 26.36 μg/m³ and 69.77 ± 41.07 μg/m³, respectively. We found that exposure to high concentrations of PM_2.5 and PM₁₀ might increase the risk of precocious puberty using the DLNM model adjusted for the age, SO₂, NO₂, CO, and O₃ levels. The strongest effects of the PM_2.5 and PM₁₀ on precocious puberty were observed in lag 27 (OR = 1.72, 95% CI: 1.01-2.92) and lag 16 (OR = 1.95, 95% CI: 1.33-2.85), respectively.

CONCLUSION

Our findings supported that short-term exposure to air pollution was the risk factor for precocious puberty. Every effort should be made to protect children from air pollution.

Exposure to antibiotics and precocious puberty in children: A school-based cross-sectional study in China

Foods and water can be contaminated with antibiotics in China, which may affect children's health, but evidence on antibiotic exposure with precocious puberty (PP) is limited. This study explored the association of antibiotic exposure with PP in a school-based setting. A cross-sectional study with multistage stratified cluster random sampling was conducted in Zhongshan City, Guangdong Province and Qufu City, Shandong Province in China from October 11 to December 5, 2019. A first-morning urine sample was collected to detect antibiotic exposure. We detected 33 of 45 types of antibiotics from eight categories in 928 primary school children aged 6-12 years using HPLS-MS/MS. Detection rate of antibiotics was stratified by sex, study site, and BMI. The Tanner stages were assessed by professional pediatricians from local hospitals. PP is defined as the onset of secondary characters before 8-year-old or menarche before 10-year-old for girls and before 9-year-old for boys. Multivariable logistic regression was performed to examine the association between antibiotic exposure and PP after adjusting potential confounders. The overall detection rate of antibiotics was 93.0% in 928 children. We found the detection rate of tetracyclines and fluoroquinolones in children with PP was significantly higher than that of children with normal puberty (41.4% vs 29.9%, 56.8% vs 50.6%, respectively, all p < 0.05). Both fluoroquinolones (odds ratio (OR): 1.835, 95% confidence interval (CI): 1.066-3.158) and tetracyclines (OR: 2.120, 95% CI: 1.175-3.825) were associated with increased OR of PP after adjusting sex, age, BMI, study site, and family income. Specifically, compared to the values less than the limits of detection, low concentration of ofloxacin from fluoroquinolones (OR: 2.056, 95% CI: 1.091-3.875) and high concentration of chlortetracycline (OR: 3.027, 95% CI: 1.126-8.140) and tetracycline from tetracyclines (OR: 2.756, 95% CI: 1.167-6.506) were associated with increased OR of PP. Exposure to antibiotics, especially fluoroquinolones and tetracyclines was positively associated with precocious puberty.

Analysis of the Relationship between Nutritional Status and Bone Age and Sexual Development in Children and Adolescents

Purpose

To observe the correlation between nutritional status, bone age, and sexual development in children and adolescents.

Methods

895 children and adolescents who underwent physical examination in the growth and development clinic and height clinic of our hospital from 2019 to 2021 were selected as the research objects. The subjects were divided into emaciation group, normal group, overweight group, and obesity group. The bone age level, bone age assessment, sexual development, and early maturity rate of each group were compared.

Results

The bone age difference (BAD) of the overweight and obesity groups was higher than that of the normal group, and the BAD of the obesity group was higher than that of the emaciation group (P < 0.05). Compared with the normal group, the risk of advancement of bone age in the overweight group increased by 2.674 times (male) and 1.908 times (female), the risk of advancement of bone age in the obesity group increased by 6.376 times (male) and 14.687 times (female), the risk of retardation of bone age in the emaciation group increased by 2.150 times (male) and 3.092 times (female). Whether it was male or female, the sexual development of overweight and obese was higher than that of the normal weight group in the same age group. Among female children, the sexual precocious puberty rate of the overweight + obesity group is higher.

Conclusion

The nutritional status of children and adolescents is closely related to their bone age and sexual development.

Antibiotic exposure and risk of overweight/obesity in school children: A multicenter, case-control study from China

BACKGROUND

Although the use of antibiotics during early life has been associated with increased risk of adipogenesis, effect of antibiotic exposure from various sources, including food or drinking water, on adiposity in children is largely unknown.

OBJECTIVE

To investigate associations between urinary biomarkers of multiple antibiotics and risk of adipogenesis in school children.

METHODS

This case-control study recruited 410 overweight/obese school children aged 6-9 years and 410 controls from Shandong and Guangdong Province, China, matched on sex, age and school. Diagnosis of overweight and obesity was based on body mass index-based criteria derived from national data. Urinary concentrations of 45 antibiotics from 8 categories (macrolides, β-lactams, tetracyclines, fluoroquinolones, sulfonamides, phenicols, lincosamides, and quinoxalines), including 6 human antibiotics (HAs), 6 antibiotics preferred as HAs (PHAs), 16 veterinary antibiotics (VAs), and 17 antibiotics preferred as VA (PVAs), were measured by ultra-performance liquid chromatography coupled to triple-quadrupole tandem mass spectrometry. Conditional logistic regression analyses were used to assess odds ratios (ORs) of childhood overweight/obesity in relation to urinary antibiotic concentrations.

RESULTS

A total of 32 antibiotics were found in urine samples with an overall detection frequency of 92.93 %. Children with overweight/obesity have higher veterinary antibiotic levels than those with normal weight. Compared with undetected levels of antibiotics, the multivariable-adjusted ORs (95 % confidence interval) of overweight/obesity for high levels of antibiotics divided according to median values were 1.63 (1.02, 2.62) for florfenicol, 1.62 (1.04, 2.54) for phenicols, and 1.41 (0.97, 2.04) for sum of VAs and PVAs. These associations predominantly existed in boys and remained significant in florfenicol after FDR multiple testing correction (FDR adjusted p < 0.05).

CONCLUSION

Exposure to certain antibiotic for veterinary use mainly from food or drinking water was associated with an increased risk of adipogenesis in children. Further studies are needed to confirm our findings and clarify the underlying mechanisms.

First morning voided urinary gonadotropins in children: verification of method performance and establishment of reference intervals

OBJECTIVES

Urinary luteinizing hormone (uLH) and urinary follicle-stimulating hormone (uFSH) have been shown to be useful screening and management tools for children with central precocious puberty. However, studies on uLH and uFSH reference intervals are scarce. Therefore, we aimed to establish reference intervals for uLH and uFSH, according to age, sex, and pubertal status in apparently healthy children aged 6-11 years.

METHODS

We performed detection capability, precision, accuracy by recovery, linearity, agreement analysis, and stability testing to analyze the method performance of uLH and uFSH. The Clinical Laboratory Standards Institute's C28-A3 criteria was used to establish the reference intervals.

RESULTS

Both uLH and uFSH were stable at 4 °C for 52.6 h and 64.8 days, respectively. The total imprecision of uFSH is within the manufacturer's claim, while the total imprecision of uLH remained within tolerable bias. Both uLH and uFSH could be measured with acceptable detection capability. The recovery rates of the hormones were 87.6-98.8% and 102.8-103.4%, respectively, and therefore within acceptable limits. There were significant correlations between the serum and urine concentrations (LH: r=0.91, p<0.001; FSH: r=0.90, p<0.001). The reference intervals of uLH and uFSH were established according to age, sex, and pubertal status.

CONCLUSIONS

We established reference intervals for uLH and uFSH based on age, sex and pubertal status to provide a non-invasive clinical screening tool for precocious puberty in children aged 6-11 years.

Identification and Optimization of Contributing Factors for Precocious Puberty by Machine/Deep Learning Methods in Chinese Girls

BACKGROUND AND OBJECTIVES

As the worldwide secular trends are toward earlier puberty, identification of contributing factors for precocious puberty is critical. We aimed to identify and optimize contributing factors responsible for onset of precocious puberty via machine learning/deep learning algorithms in girls.

METHODS

A cross-sectional study was performed among girls aged 6-16 years from 26 schools in Beijing based on a cluster sampling method. Information was gleaned online via questionnaires. Machine/deep learning algorithms were performed using Python language (v3.7.6) on PyCharm platform.

RESULTS

Of 11308 students enrolled, there are 5527 girls, and 408 of them had experienced precocious puberty. Training 13 machine learning algorithms revealed that gradient boosting machine (GBM) performed best in predicting precocious puberty. By comparison, six top factors including maternal age at menarche, paternal body mass index (BMI), waist-to-height ratio, maternal BMI, screen time, and physical activity were sufficient in prediction performance, with accuracy of 0.9530, precision of 0.9818, and area under the receiver operating characteristic curve (AUROC) of 0.7861. The performance of the top six factors was further validated by deep learning sequential model, with accuracy reaching 92.9%.

CONCLUSIONS

We identified six important factors from both parents and girls that can help predict the onset of precocious puberty among Chinese girls.

The critical BMI hypothesis for puberty initiation and the gender prevalence difference: Evidence from an epidemiological survey in Beijing, China

BACKGROUND

Although previous studies suggested that there is a certain level of body fat mass before puberty can be initiated, most studies have focused on girls.

OBJECTIVE

To investigate the relationship between precocious puberty and physical growth in school-aged children in Beijing, China.

METHODS

7590 Chinese children (3591 girls and 3999 boys) aged 6-11 years were recruited in Beijing, China. Body mass index (BMI) categories were defined by WHO Child Growth Standards and central obesity were defined by sex-specific waist-to-height ratio cut-offs (≥0.46 for girls, ≥0.48 for boys). Sexual development was assessed using Tanner criteria.

RESULTS

The prevalence of general obesity and central obesity among boys was higher than that in girls. Girls had a significantly higher precocious puberty rate than boys (5.93% vs. 0.87%), particularly in those aged 7 years old (9.20%). Children in the general obesity and central obesity groups have a higher prevalence of precocious puberty and earlier median ages for the attainment of Tanner B₂/T₂. For girls with Tanner stages≥II at 6-year-old and 7-year-old, the mean BMI was equivalent to the 50th centile of a normal 9.9-year-old and 11.9-year-old girl, respectively. The mean BMI of boys with Tanner stages≥II at 7-year-old and 8-year-old was correspondent to the 50th centile of a normal 14-year-old and 15.3-year-old boy, respectively. For girls, general obesity appears to contribute to the risk of the development of precocious puberty to a greater extent than central obesity does. For boys, central obesity, but not general obesity, was an independent risk factor for precocious puberty.

CONCLUSIONS

The prevalence of childhood obesity and precocious puberty was high in China. Precocious puberty was correlated with a large BMI. Boys had a higher threshold of BMI for puberty development than girls. Children with precocious puberty, particularly those with central obesity, should be aware of adverse cardiovascular events.

Analysis of the Incidence and Risk Factors of Precocious Puberty in Girls during the COVID-19 Pandemic

Home quarantine due to the global coronavirus disease 2019 (COVID-19) pandemic has had a significant impact on children. Lifestyle changes have led to an increase in precocious puberty (PP) among girls, and the underlying risk factors for this remain unclear. Thus, we aimed to assess the influence of environmental, genetic, nutritional, and other lifestyle factors on the risk of PP in girls. We evaluated the incidence of new-onset PP in girls during home quarantine for COVID-19 and analyzed the potential risk factors. This was a retrospective questionnaire and medical record-based study involving 22 representative medical units from 13 cities in Henan Province, China. Girls with new-onset PP (central precocious puberty, 58; premature thelarche, 58; age, 5-9 years) between February 2020 and May 2020 were included, along with 124 healthy, age-matched controls. The number of new-onset PP cases reported during the study period was compared with that reported between February and May in 2018 and 2019. Patients' families completed a questionnaire to assess potential risk factors. There was a 5.01- and 3.14-fold increase in the number of new-onset PP cases from 2018 to 2020 and from 2019 to 2020, respectively; the differences were statistically significant (p < 0.01). High-risk factors for PP included longer time spent using electronic devices, decreased exercise time, higher body mass index, vitamin D deficiency, young age (<12 years) of mother during menarche, consumption of fried food and processed meat, residence in rural areas, and consumption of off-season fruits. Thus, we found that lifestyle changes caused due to the COVID-19 pandemic led to a significant increase in PP in girls. Management of the risk factors identified in this study may help in PP prevention.

An Approach to the Evaluation and Management of the Obese Child With Early Puberty

With the declining age at onset of puberty and increasing prevalence of childhood obesity, early breast development in young obese girls has become a more frequent occurrence. Here, we examine available literature to answer a series of questions regarding how obesity impacts the evaluation and management of precocious puberty. We focus on girls as the literature is more robust, but include boys where literature permits. Suggestions include: (1) Age cutoffs for evaluation of precocious puberty should not differ substantially from those used for nonobese children. Obese girls with confirmed thelarche should be evaluated for gonadotropin-dependent, central precocious puberty (CPP) to determine if further investigation or treatment is warranted. (2) Basal luteinizing hormone (LH) levels remain a recommended first-line test. However, if stimulation testing is utilized, there is a theoretical possibility that the lower peak LH responses seen in obesity could lead to a false negative result. (3) Advanced bone age (BA) is common among obese girls even without early puberty; hence its diagnostic utility is limited. (4) Obesity does not eliminate the need for magnetic resonance imaging in girls with true CPP. Age and clinical features should determine who warrants neuroimaging. (5) BA can be used to predict adult height in obese girls with CPP to inform counseling around treatment. (6) Use of gonadotropin-releasing hormone analogues (GnRHa) leads to increased adult height in obese girls. (7) Obesity should not limit GnRHa use as these agents do not worsen weight status in obese girls with CPP.

The concordance between ultrasonographic stage of breast and Tanner stage of breast for overweight and obese girls: a school population-based study

OBJECTIVES

In this study, we evaluated the concordance between the ultrasonographic stage of breast (US B) and Tanner stage of breast (TS B) for overweight and obese girls based on a school population study.

METHODS

We conducted multistage, stratified cluster, and random-proportional sampling and ultimately included 221 girls (aged 6-10 years).

RESULTS

This study revealed that the concordance was poor (accuracy=0.19 (95% confidence interval: 0.14, 0.25)) between US B and TS B among the 221 participants. When our subjects were stratified by weight, we observed a weak association between US B and TS B in the thin/normal weight group (r=0.34, p=0.001) but not in the overweight (r=0.097, p=0.38) or obese groups (r=-0.19, p=0.206), and as the body mass index (BMI) z-score increased, the overestimation ratio of TS B increased. US B manifested a positive correlation with breast bud diameter (BD) (r=0.885, p<0.001), follicle-stimulating hormone (r=0.235, p=0.009), and luteinizing hormone (r=0.192, p=0.037), but this was not the case with TS B.

CONCLUSIONS

As the BMI z-score increased, the correlation between the two methods declined, and the overestimation ratio of TS B increased. US B is an objective and quantitative method used to evaluate breast development, and whether BD might replace US B as a routine diagnostic method to evaluate breast development in clinical practice needs to be confirmed in larger-sample studies.

Obesity is a risk factor for central precocious puberty: a case-control study

BACKGROUND

Obesity is an important underlying cause of central precocious puberty (CPP), but previous large studies are flawed by using just age and breast examination to diagnose CPP. We aimed to determine whether overweight and obesity in childhood increases hormonally diagnosed CPP.

METHODS

Our retrospective, case-control study recruited 846 children diagnosed as having CPP and randomly sampled 1650 healthy control subjects in Xingtai Third Hospital in China between November 2018 and March 2021. Information was obtained from an electronic medical record and questionnaire investigated in the outpatient visit. Observations were made before the a priori hypothesis. Unconditional logistic regression for analysis was used to determine whether overweight and obesity status and duration of overweight/obesity were associated with CPP.

RESULTS

Overweight and obesity were significantly associated with increased odds of CPP among girls, even after adjusting for birth weight, exclusive breastfeeding for 6 month, household income, maternal overweight, paternal overweight, and maternal menarche age (overweight: the adjusted odds ratio (aOR) (95%CI): 1.92 (1.16, 3.24), p = 0.02; obesity: aOR (95%CI): 1.78 (1.13, 3.48), p = 0.03). Furthermore, the effects of overweight and obesity were significant when ongoing for 1 to 2 years, 2 to 3 years, and greater than 3 years, but not at less than 1 year. For boys, association between obesity and increased odds of CPP was observed (aOR (95%CI): 1.68 (1.09, 3.75), p = 0.03). The effects of overweight and/or obesity were only significant when ongoing for greater than 2 years.

CONCLUSIONS

Prolonged overweight and obesity in early childhood may be risk factors for CPP, especially in girls. Weight loss might be an important approach for the prevention of precocious puberty in children.

The link between obesity and puberty: what is new?

PURPOSE OF REVIEW

The objective of this review is to assess the most recent literature on pubertal trends in boys and girls as well as evaluate genetic, epigenetic, and environmental factors implicated in the timing of pubertal progression.

RECENT FINDINGS

Recent studies confirm the previously described link between increased adiposity and earlier onset of puberty in girls, and more recent studies shed light onto the previously unclear situation in boys as a preponderance of recent longitudinal studies suggests that increased adiposity is linked with earlier pubertal timing also in boys. Discoveries of novel pathways highlights the complexity of pubertal development and suggest mechanistic links between nutrition, obesity, leptin, insulin resistance, and puberty. Furthermore, genetic and epigenetic variants can be linked to early puberty. Other factors, such as prenatal and postnatal environment, gut microbiota, and endocrine-disrupting chemicals have also been linked to both obesity and earlier puberty.

SUMMARY

Understanding how the interactions of these factors contribute the relationship between obesity and early pubertal onset is crucial as early puberty has been linked with long-term consequences, such as short stature, earlier type 2 diabetes, cardiovascular disease, and poor psychological and behavioral outcomes.