An increasing tendency of precocious puberty among Korean children from the perspective of COVID-19 pandemic effect

Difference in precocious puberty between pre-COVID-19 and COVID-19 periods: a meta-analysis

We conducted this systematic review and meta-analysis to clarify the trend of precocious puberty (PP) incidence after the COVID-19 outbreak and explore potential contributing factors, such as age at presentation and body mass index (BMI) SD score (SDS). Children visiting pediatric endocrinology clinics for the first time for suspected PP were included. We searched databases until February 28, 2023, for studies reporting various indicators of PP incidence before and during the pandemic. Total numbers of events and observations were recorded. A meta-analysis was performed to compare the odds of PP, BMI SDS, and age at presentation between the 2 periods. The dose-response relationships between time points (by number of years away from the pandemic) and PP risk were explored. In summary, a total of 32 studies including 24 200 participants were recruited. The COVID-19 pandemic was associated with the increasing odds of PP among children referred for a suspicious condition (odds ratio = 1.96; 95% CI, 1.56-2.47; I2 = 54%; P < .001). Sensitivity analysis confirmed the robustness of the findings. The BMI SDS did not vary between the 2 periods, whereas age at presentation was lower after the pandemic. Precocious puberty incidence increased more rapidly during the pandemic period than during the prepandemic period. Trial registration: International Prospective Register of Systematic Reviews (PROSPERO; identifier: CRD42023402212).

Diet Quality Scores and Central Precocious Puberty Risk in Chinese Girls: A Case-Control Study

OBJECTIVE

Diet is an important factor influencing central precocious puberty (CPP). This study aimed to investigate the relationship among diet quality, pro-inflammatory diets, and CPP in Chinese girls.

DESIGN, PATIENTS AND MEASUREMENTS

This case-control study enroled 112 Chinese girls with CPP and 131 healthy controls. Children's dietary intake was assessed using a validated food frequency questionnaire, anthropometric and sociodemographic data were collected and serum interleukin-6 levels were measured. We calculated the Children's Dietary Inflammatory Index (C-DII), Chinese Children's Dietary Index (CCDI), Dietary Approaches to Stop Hypertension (DASH) score, and the adjusted Dietary Approaches to Stop Hypertension (aDASH) score. The association between diet and the risk of CPP was analysed using logistic regression models.

RESULTS

After adjustment, higher C-DII scores were associated with an increased risk of CPP (P for trend = 0.034), and aDASH scores were significantly negatively associated with the risk of CPP (P for trend = 0.048). Serum IL-6 levels were significantly higher in the case group than in the control group and were positively correlated with the risk of CPP (P for trend = 0.006).

CONCLUSIONS

High-quality dietary patterns and an anti-inflammatory diet may contribute to the prevention of CPP in Chinese girls.

Serum phoenixin levels in girls with central precocious puberty and premature thelarche

BACKGROUND AND AIM

Phoenixin (PNX), a newly discovered neuropeptide associated with reproduction, has been speculated to be involved in precocious puberty. Therefore, we assessed serum PNX levels in girls with precocious puberty.

METHODS

Serum phoenixin-14 (PNX-14) and phoenixin-20 (PNX-20) levels were determined in girls with central precocious puberty (CPP) and premature thelarche (PT) and in healthy controls (n = 58 per group). Spearman's correlation was used to analyze the correlations between variables. Receiver operating characteristic curves were used to evaluate the performance of PNX for the diagnosis of CPP. Significant predictors of serum PNX levels were determined using least absolute shrinkage and selection operator regression and multiple linear regression analyses.

RESULTS

Serum PNX-14 and PNX-20 levels were significantly higher in girls with CPP than in the controls; however, no significant differences in serum PNX-14 and PNX-20 levels were observed between girls with PT and the controls. PNX-20 levels were positively correlated with basal luteinizing hormone (LH) levels, peak LH levels, the peak LH to follicle-stimulating hormone (FSH) ratio, and estradiol levels. No significant correlation was observed between PNX-14 levels and any of these parameters. Multivariate linear regression analysis revealed that PNX-20 levels exhibited the strongest correlation with peak LH/FSH values. The areas under the curve (AUCs) of PNX-14 and PNX-20 for predicting CPP were 0.628 (cut-off value, 100.12 pg/mL; sensitivity, 44.6%; specificity, 77.6%) and 0.775 (cut-off value, 360.03 pg/mL; sensitivity, 66.5%; specificity, 79.3%), respectively. When these two indicators were combined, the AUC was 0.785.

CONCLUSIONS

Serum PNX levels may be associated with precocious puberty in girls and can be used as an auxiliary CPP indicator. However, given the low sensitivity and specificity of PNX, it should not be used as a single diagnostic indicator of CPP.

Clinical and epidemiological insights into early puberty in Thai girls: a 5-year study

PURPOSE

There is growing global concern about the shift to earlier onset of puberty among girls; however, the prevalences of precocious and normal variant puberty among Thai girls are uncertain. We conducted a study at King Chulalongkorn Memorial Hospital in Bangkok from 2018 to 2022 (amid the coronavirus disease 2019 pandemic) to investigate the prevalence, characteristics, and treatment of early puberty in a large cohort of Thai girls.

METHODS

The medical records of 583 girls who had been evaluated for early puberty were reviewed. Demographic and clinical characteristics, and treatment approaches were analyzed.

RESULTS

The analyses found a significant annual increase in evaluations for early signs of puberty (P-value for trend 0.04). The majority (71.2%) of cases were categorized as gonadotropin-releasing-hormone (GnRH)-dependent or central precocious puberty (CPP), with 16 cases showing abnormal brain magnetic resonance imaging findings. Among girls with normal variant puberty, early normal puberty was the most common category (10.5%), followed by premature thelarche (9.5%), slow-progressive precocious puberty (6.6%), and premature adrenarche (2.2%). Median age at presentation, basal luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and bone age differed significantly among groups. Importantly, 97% of girls with CPP received GnRH agonists. Girls with CPP exhibited higher body mass index z-scores and basal LH and FSH compared with those with slow-progressive precocious puberty.

CONCLUSION

Our analyses of the prevalence, characteristics, and treatment of early puberty in Thai girls highlighted the impact of obesity on pubertal timing. The findings underscore the need for preventive weight management and country-specific guideline updates to enhance healthcare strategies for young girls.

Central Precocious Puberty During the COVID-19 Pandemic Period: A Systematic Review of Literature

Central precocious puberty (CPP) is a condition where the hypothalamus-pituitary-gonadal axis is activated earlier than normal, leading to premature development of secondary sexual characteristics before eight years of age in girls and nine years of age in boys. The purpose of this study was to critically and systematically evaluate the literature regarding CPP rise during the COVID-19 pandemic. We searched PubMed and Google Scholar for relevant articles using the following MeSH terms: "COVID-19, "precocious puberty," "early puberty," "pediatric endocrinology," and "pandemic effects." We included studies calculating the risk of CPP before and during the COVID-19 pandemic. We excluded studies looking at patients with an identifiable cause for CPP or with peripheral precocious puberty. The primary outcome was the prevalence of central precocious puberty during the pandemic compared to the pre-pandemic period. We analyzed data regarding anthropometric, biochemical, and pelvic ultrasound data between the two groups. Overall, 16 studies with 2.175 subjects were included, of which 1.818 were diagnosed with CPP. There was a rise in the number of new diagnoses of CPP during the COVID-19 pandemic (985 subjects) compared with the pre-pandemic period (833 subjects). The mean age of diagnosis in the first group was 7.42 years versus 7.54 years in the second group. Notably, CPP during the pandemic was associated with a higher body mass index (BMI) compared with the group of the pre-pandemic period (17.50 versus 17.08). The pandemic and lockdowns led to changes in lifestyle habits, social isolation, sleep disturbance, excess screen time, and increased stress levels. We hypothesize that these alterations influenced the increase in CPP frequency.

Navigating Pubertal Goldilocks: The Optimal Pace for Hierarchical Brain Organization

Adolescence is a timed process with an onset, tempo, and duration. Nevertheless, the temporal dimension, especially the pace of maturation, remains an insufficiently studied aspect of developmental progression. The primary objective is to estimate the precise influence of pubertal maturational tempo on the configuration of associative brain regions. To this end, the connection between maturational stages and the level of hierarchical organization of large-scale brain networks in 12-13-year-old females is analyzed. Skeletal maturity is used as a proxy for pubertal progress. The degree of maturity is defined by the difference between bone age and chronological age. To assess the level of hierarchical organization in the brain, the temporal dynamic of closed eye resting state high-density electroencephalography (EEG) in the alpha frequency range is analyzed. Different levels of hierarchical order are captured by the measured asymmetry in the directionality of information flow between different regions. The calculated EEG-based entropy production of participant groups is then compared with accelerated, average, and decelerated maturity. Results indicate that an average maturational trajectory optimally aligns with cerebral hierarchical order, and both accelerated and decelerated timelines result in diminished cortical organization. This suggests that a "Goldilocks rule" of brain development is favoring a particular maturational tempo.

Endocrinological Involvement in Children and Adolescents Affected by COVID-19: A Narrative Review

Since the advent of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, an increased incidence of several endocrinological anomalies in acute-phase and/or long-term complications has been described. The aim of this review is to provide a broad overview of the available literature regarding changes in the worldwide epidemiology of endocrinological involvement in children since December 2019 and to report the evidence supporting its association with coronavirus disease 2019 (COVID-19). Although little is known regarding the involvement of endocrine organs during COVID-19 in children, the current evidence in adults and epidemiological studies on the pediatric population suggest the presence of a causal association between the virus and endocrinopathies. Untreated transient thyroid dysfunction, sick euthyroid syndrome, nonthyroidal illness syndrome, and hypothalamic-pituitary-adrenal (HPA) axis and central precocious puberty have been observed in children in acute infection and/or during multisystem inflammatory syndrome development. Furthermore, a higher frequency of ketoacidosis at onset in children with a new diagnosis of type 1 diabetes is reported in the literature. Although the direct association between COVID-19 and endocrinological involvement has not been confirmed yet, data on the development of different endocrinopathies in children, both during acute infection and as a result of its long-term complications, have been reported. This information is of primary importance to guide the management of patients with previous or current COVID-19.

Is blue light exposure a cause of precocious puberty in male rats?

Purpose

Our study aimed to examine the effects of blue light exposure on prepubertal male rats' puberty and testis tissue.

Methods

Eighteen 21-day-old male Sprague Dawley rats were divided into three groups consisting of six rats in each group: Control Group (CG), Blue Light-6 hours (BL-6), and Blue Light-12 hours (BL-12). CG rats were maintained with 12/12-hour light-dark cycles. The rats of BL-6 and BL-12 were exposed to blue light (450-470nm/irradiance level 0.03uW/cm2) for 6 hours and 12 hours, respectively. Rats were exposed to blue light until the first signs of puberty. The ELISA method was used to analyze the serum levels of FSH, LH, testosterone, DHEA-S, leptin, ghrelin, melatonin, glutathione, glutathione peroxidase, and malondialdehyde. Testes were dissected for histomorphological examination.

Results

The medians of the pubertal entry days of the CG, BL-6, and BL-12 were 38^th, 30^th, and 28^th days, respectively. (p:0.001) The FSH, LH, and testosterone concentrations of all groups were similar. The FSH concentration increased as the LH concentration increased (r: 0.82 p: 0.001). The serum LH concentration increased as serum testosterone, and DHEAS decreased, respectively (r: -0.561, p: 0.01) (r:-0.55 p:0.01). Testicular lengths and weights of the BL groups were smaller compared to CG (p: 0.03),(p: 0.04). GPx was higher for BL-6 and BL-12 than the CG (p:0.021, p:0.024). Testis tissue was compatible with the pubertal period in all groups. As the blue light exposure time increased, spermatogenesis was suppressed, and capillary dilatation and edema in the testis tissue increased.

Conclusion

Our study is the first to show the effects of blue light exposure on male rats' puberty process. And we showed that exposure to blue light and the duration of exposure lead to precocious puberty in male rats. The blue light exposure suppressed spermatogenesis, marked vasodilatation in the interstitial area of the testis, and disrupted the integrity of the basement membrane. These findings intensified with increasing exposure time.

Early onset of puberty during COVID-19 pandemic lockdown: experience from two Pediatric Endocrinology Italian Centers

OBJECTIVES

During COVID-19 pandemic lockdown, reports of evaluations for suspected precocious puberty significantly raised. We aimed to assess the increase of precocious puberty in patients referred to Pediatric Endocrinology Units of Brescia (Italy), to determine clinical characteristics of patients undergoing a GnRH stimulation test before and during lockdown and evaluate the role of environmental factors in pubertal development.

METHODS

Clinical and biochemical data of patients undergoing GnRH stimulation test were collected and stratified in two groups: March 2019 - February 2020 (Period 1) and March 2020 - February 2021 (Period 2).

RESULTS

A total number of 391 evaluations for suspected precocious puberty were identified in the two study periods: 183 (46.8%) first visits during Period 1, and 208 (53.2%) in Period 2. Sixty-one patients underwent a GnRH stimulation test (4.1% of first consultations) before the SARS-CoV2 pandemic, and 93 children (8.7%) after the lockdown. Thirty-four new diagnoses of central precocious puberty were registered during Period 1 (2.3%), vs. 45 new cases (4.2%) in Period 2. During lockdown patients evaluated for suspected precocious puberty underwent a stimulation test at younger age than those evaluated before pandemic (median age of 8.2 years vs. 8.4, p=0.04). In Period 2, children showed a median bone age advancement of 0.61 years vs. 1.06 of Period 1 (p=0.03).

CONCLUSIONS

During the COVID-19 pandemic, we observed an increased proportion of consultations for suspected precocious puberty. These children showed lower bone age advancement than observed in pre-lockdown suggesting the influence of pandemic-related lifestyle changes on pubertal development.

Pandemic and precocious puberty - a Google trends study

BACKGROUND

Recent publications from several countries have reported that more young people (mainly girls) are experiencing precocious puberty (PP)/menarche during the coronavirus disease 2019 pandemic compared to the past. This variation is attributed to the stress of confinement, lack of exercise, obesity and disturbed sleep patterns. A common feature of the relevant papers, however, is the small number of reported cases of PP. Studies have shown that searches for diseases on the internet also reflect to some extent the epidemiology of these diseases.

AIM

To estimate, through internet searches for PP, any changes in the epidemiology of PP.

METHODS

We assessed in Google Trends searches for 21 PP-related terms in English internationally (which practically dwarf searches in other languages), in the years 2017-2021. Additionally, we assessed local searches for selected terms, in English and local languages, in countries where a rise in PP has been reported. Searches were collected in Relative Search Volumes format and analyzed using Kendall’s Tau test, with a statistical significance threshold of P < 0.05.

RESULTS

Internationally, searches for three PP-related terms showed no noticeable change over the study period, while searches for eight terms showed a decrease. An increase was found over time in searches for nine PP-related terms. Of the 17 searches in English and local languages, in countries where a rise in PP has been reported, 5 showed a significant increase over time.

CONCLUSION

Over the study period, more than half of the search terms showed little change or declined. The discrepancy between internet searches for PP and the reported increase in the literature is striking. It would be expected that a true increase in the incidence of PP would also be aptly reflected in Google trends. If our findings are valid, the literature may have been biased. The known secular trend of decreasing age of puberty may also have played a role.

COVID-19 pandemic phases and female precocious puberty: The experience of the past 4 years (2019 through 2022) in an Italian tertiary center

OBJECTIVE

Since the outbreak of COVID-19 pandemic, several centers of pediatric endocrinology worldwide have observed a significant increase in the number of girls presenting with precocious or early puberty. We aimed to compare the incidence rates of female precocious puberty before and during the different phases of COVID-19 pandemic.

METHODS

We have retrospectively analyzed all the consultations recorded in the outpatient clinic database of the Endocrinology Unit of Bambino Gesù Children's Hospital, Rome, Italy, from the lockdown start in March 2020 up to September 2020, in comparison with the consultations recorded in the same months of 2019, 2021 and 2022. Age, height, weight, body mass index, Tanner's pubertal stage and bone age at presentation, birth weight, ethnicity, family history of central precocious puberty (CPP), maternal age at menarche, history of adoption were retrieved from clinical records. Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH) both at baseline and after gonadotropin-releasing hormone (GnRH) stimulation, and basal estradiol levels were collected.

RESULTS

In 2019, 78 girls with suspected precocious puberty were referred for endocrinological consultation, compared to 202 girls in 2020, 158 girls in 2021 and 112 girls in 2022. A significant increase in the proportion of girls diagnosed with rapidly progressive CPP was observed in 2020, compared to 2019 (86/202 vs. 18/78, p<0.01). In the following periods of 2021 and 2022, a gradual decrease in the number of cases of progressive CPP was evident, so much that the number of cases was not significantly different from that observed in 2019 (56/158 in 2021 and 35/112 in 2022, p=0.054 and p=0.216 respectively, compared to 2019).

CONCLUSIONS

Our research suggests that drastic lifestyle changes, such as those imposed by COVID-19 lockdown, and the consequent stress may affect the regulation of pubertal timing. The remarkable increase in CPP cases observed during the 2020 first pandemic wave seems to be reduced in 2021 and 2022, concurrently with the progressive resumption of daily activities. These data seem to support the hypothesis of a direct relationship between profound life-style changes related to the pandemic and the rise in precocious puberty cases.

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.

Gonadotropin-releasing hormone analogue and recombinant human growth hormone treatment for idiopathic central precocious puberty in girls

PURPOSE

To investigate the effectiveness and safety of gonadotropin-releasing hormone analogue (GnRHa) in combination with recombinant human growth hormone (rhGH) in girls with central precocious puberty (CPP).

METHODS

Clinical data of 80 girls diagnosed with idiopathic central precocious puberty (ICPP) between January 2017 and June 2021 were retrospectively analyzed. Treatment strategy involved GnRHa alone (group A: n=34) and GnRHa+rhGH (group B: n=46). Children's heights (Ht), weights (Wt) and sex hormone levels were measured every 3 months after treatment and bone age (BA) every six months. Heights, growth velocity (GV), predicted adult height (PAH), weights, body mass index (BMI), sex hormone levels and bone age were compared between the two groups.

RESULTS

Children in group B showed greater height gain at the 12th, 24th and 30th months after treatment (p<0.05) than those in group A, had faster growth rates in the first and second year following treatment (p<0.05) and better PAH (p<0.05). No statistical differences in weight or BMI were found between the two groups before treatment or at any time after treatment (p>0.05). Levels of LH and FSH were lower in both groups after treatment with no statistical differences between groups (p>0.05). The gap between bone age and chronological age gradually decreased in both groups and no abnormal progression of bone age or other adverse side effects occurred.

CONCLUSIONS

The combination of GnRHa with rhGH produced better height gains than GnRHa alone for patients with CPP. The gonadal axis was suppressed and progression of bone age delayed with good safety and efficacy.

Early and precocious puberty during the COVID-19 pandemic

During the year 2020, the COVID-19 pandemic rapidly became a severe health emergency worldwide. In order to contrast the spread of the novel SARS-CoV-2, many countries implemented extraordinary restrictive measures, such as a strict lockdown and school closures. The pandemic had a great impact on children and adolescents' daily life, leading to a much more sedentary lifestyle, to larger use of electronic devices and to an increase in stress-related symptoms. These conspicuous changes acted as disruptors of children's normal development. Since the beginning of the pandemic, many studies reported an increase in the number of precocious puberty cases as well as a faster progression rate of puberty itself, if compared to the pre-pandemic years. In this review, our aim was to evaluate the incidence of new cases of early and precocious puberty during the COVID-19 pandemic, analyzing variations in the timing of puberty and in pubertal progression rate, and to investigate the role of environmental and lifestyle factors during the pandemic in modulating the physiopathology of pubertal development. While a direct effect of SARS-CoV-2 infection remains, at the moment, a remote hypothesis, both physical and psychological factors related to the pandemic seem to have a role in triggering GnRH pulsatile secretion leading to earlier pubertal onset. It is indeed important to stress the need to clarify the exact role of COVID-19 in early pubertal onset comparing data from all over the world; long-term comprehensive studies are also pivotal to explain whether this phenomenon will continue while we resume pre-pandemic habits.