National Blood Pressure Reference for Chinese Han Children and Adolescents Aged 7 to 17 Years

The associations of insulin resistance, obesity, and lifestyle with the risk of developing hyperuricaemia in adolescents

BACKGROUND

Hyperuricaemia is common among obese children and adolescents, and is closely related to insulin resistance. The aim of this study was to explore the relationships between youth insulin resistance and hyperuricaemia, as well as their relationships with lifestyle factors in youths, to provide early guidance on the risk factors for hyperuricaemia in adolescents.

METHODS

This study included 233 adolescents aged 10 to 20 years. Insulin resistance was evaluated via the homeostasis model assessment-insulin resistance (HOMA-IR) method. Binary logistic regression analysis was used to assess the associations of HOMA-IR with hyperuricaemia status and serum uric acid (UA) levels. The participants were subsequently divided into two groups, the noninsulin resistant group (HOMA-IR ≤ 3.2) and the insulin resistant group (HOMA-IR > 3.2), to further explore the factors that may affect the serum UA level. Finally, the predictive ability of different indicators of hyperuricaemia was evaluated via the ROC curve.

RESULTS

Binary logistic regression analysis revealed a significant increase in the risk of developing hyperuricaemia for individuals with elevated HOMA-IR (p < 0.001) and insulin resistance (p < 0.01). Spearman's correlation analysis revealed a significant positive linear correlation between HOMA-IR and serum UA levels (r = 0.4652, p < 0.001). Among insulin-resistant adolescents, UA levels were positively correlated with weight ratings, frequency of staying up late, and sugary beverages intake. Notably, individuals who engaged in 1-3 h of weekly exercise had the lowest UA levels. The area under the ROC curve for HOMA-IR was 0.847 (cut-off value = 2.165, p < 0.001), and the optimal prediction model included HOMA-IR, BMI z-score, and other lifestyle factors (AUC: 0.870, p < 0.001)).

CONCLUSION

HOMA-IR was identified as an independent risk factor for the development of hyperuricaemia and could be used as a sensitive indicator for the prediction its development in adolescents. In insulin-resistant adolescents with hyperuricaemia, maintaining normal weight, engaging in physical exercise for 1-3 h per week, avoiding staying up late and limiting sugary beverages intake are recommended to reduce the prevalence of hyperuricaemia among adolescents.

Dietary and activity habits associated with hypertension in Kunming school-aged children and adolescents: A multilevel analysis of the study of hypertension risks in children and adolescents

Objective

Hypertension has become a public health challenge for Yunnan children and adolescents. The study aims is to assess the dietary and activity habits associated with hypertension in Kunming children and adolescents and to develop effective strategies for preventing and controlling, Southwest China.

Methods

Conducted in 2019, the cross-sectional study involved 3,150 students, aged 13.25 ± 2.77 years, multistage, stratified, randomly sampled from Chenggong and Fumin areas, Southwest China.

Results

Among 3,150 participants, 6.19 % never drank milk, 3.46 % never consumed fresh fruit. 2.67 % never consumed fresh vegetables, 2.48 % never ate breakfast and 10.06 % frequently drank sugary beverages (soft drinking). Additionally, 21.56 % engaged in moderate-intensity exercise less than one Day a week, and 31.97 % performed high-intensity exercise less than one Day a week. The intraclass correlation coefficient indicated that 49.40 % of the total variance was attributed to the dietary level and 42.10 % was attributed to the activity level. Eating fresh vegetables and fruit, taking physical education classes they attended per week and the frequency of moderate-intensity and high-intensity exercise per week were independent protective factors for hypertension (P < 0.01); drinking sugary beverages (soft drinking) was a independent risk factor against hypertension (P < 0.05); breakfast skipping was a possible risk factor for hypertension (P < 0.15). No significant associations were found with fried food or sweet food weekly consumption (P < 0.15).

Conclusions

The hypertension of children and adolescents cannot be ignored in Kunming, Southwest china. Dietary and activity factors are modifiable. We should make comprehensive child-friendly health education materials as soon as possible.

Joint Trajectories of Lifestyle Indicators and Their Associations with Blood Pressure among Chinese Middle School Students

Lifestyle behaviors, defined as a combination of dietary behavior, physical activity (PA), screen time (ST), and sleep duration indicators, are strongly associated with blood pressure (BP) in students. Our aim was to characterize the joint trajectories of lifestyle behaviors among middle school students and evaluate their association with BP. Data were obtained from the monitoring dataset on common diseases and health factors among students in Jiading District, Shanghai, China, conducted from 2019 to 2023. Lifestyle behavior data were collected annually from middle school students aged 12-18 years through questionnaires covering dietary behavior score, PA, ST, and sleep duration. Students' BP was measured in 2023. Joint trajectories of lifestyle behaviors were determined using group-based multi-trajectory modeling. Associations between lifestyle trajectories and students' BP were examined using multiple linear regression and modified Poisson regression. A total of 1378 middle school students (759 [58.98%] boys, median age 14.36 years [IQR: 13·30-13.28]) with lifestyle behaviors data assessed at least three times were included, and they were categorized into four joint lifestyle trajectories as follows: "remain unhealthy with low PA and increasing ST" (n = 141, 10.46%), "remain unhealthy with only low PA" (n = 305, 22.63%), "change towards unhealthy with decreasing sleep duration" (n = 776, 57.57%), and "relatively healthy" (n = 126, 9.35%). After adjusting for important confounders, the "remain unhealthy with low PA and increasing ST" group was associated with higher diastolic BP (DBP) [β: 3.49, 95% CI: 0.55-6.44] and higher mean arterial pressure (MAP) [β: 3.19, 95% CI: 0.37-6.01] in students compared with the "relatively healthy" group. Additionally, compared with the "relatively healthy" group, students in the "remain unhealthy with low PA and increasing ST" group had a 1.12-fold increase in the risk of hypertension (risk ratios: 1.12, 95% CI: 1.03-1.24). All trend p values in DBP, MAP, and hypertension from the "relatively healthy" group to the "remain unhealthy with low PA and increasing ST" group were less than 0.05. Four distinct lifestyle trajectories were identified among middle school students. Students who remained in the "unhealthy with low PA and increasing ST" lifestyle trajectory were associated with later elevations in BP.

Association of the external environmental exposome and obesity: A comprehensive nationwide study in 2019 among Chinese children and adolescents

OBJECTIVE

Children and adolescents are particularly vulnerable to the effects of various environmental factors, which could disrupt growth processes and potentially lead to obesity. Currently, comprehensive and systematic assessments of these environmental exposures during developmental periods are lacking. Therefore, this study aims to evaluate the association between external environmental exposures and the incidence of obesity in children and adolescents.

METHODS

Data was collected from the 2019 Chinese National Survey on Students' Constitution and Health, including 214,659 Han children aged 7 to 19. Body Mass Index (BMI) and BMI-for-age z-score (zBMI) were the metrics used to assess overweight and obesity prevalence. The study assessed 18 environmental factors, including air pollutants, natural space, land cover, meteorological conditions, built environment, road conditions, and artificial light at night. Exposome-wide association study (ExWAS) to analyze individual exposures' associations with health outcomes, and Weighted Quantile Sum (WQS) to assess cumulative exposure effects.

RESULTS

Among the children and adolescents, there were 24.2 % participants classified as overweight or obesity. Notably, 17 out of 18 environmental factors exhibited significant associations with zBMI and overweight/obesity. Seven air pollutants, road conditions, and built density were positively correlated with higher zBMI and obesity risk, while NDVI, forests, and meteorological factors showed negative correlations. Co-exposure analysis highlighted that SO2, ALAN, PM10, and trunk road density significantly increased zBMI, whereas rainfall, grassland, and forest exposure reduced it. Theoretically reduction in the number and prevalence of cases was calculated, indicating potential reductions in prevalence of up to 4.51 % for positive exposures and 5.09 % for negative exposures. Notably, substantial reductions were observed in regions with high pollution levels.

CONCLUSION

This large-scale investigation, encompassing various environmental exposures in schools, highlights the significant impact of air pollution, road characteristics, rainfall, and forest coverage on childhood obesity.

Urban greenspaces and child blood pressure in China: Evidence from a large population-based cohort study

BACKGROUND

With the world's population steadily shifting toward urban living, children's engagement with the natural environment seems to be diminishing. This raises significant concerns about the influence of urban greenspaces on the cardiovascular health of children.

OBJECTIVE

To assess the association between urban greenspaces exposure and blood pressure (BP) in Chinese primary schoolchildren.

METHODS

This prospective cohort study used data from the Children's growth environment, lifestyle, physical, and mental health development (COHERENCE) project in Guangzhou, China. Participants included 164,853 primary schoolchildren starting from 2016/17 to 2019/20 academic year. We assessed the surrounding greenspaces at home and school by using Sentinel-2 satellite data on the normalized difference vegetation index. Prehypertension and hypertension status were defined with BP above 90th to less than the 95th percentile, at or above the 95th percentile, respectively. The association of surrounding greenness with children's BP levels and risk of prehypertension/hypertension were examined using linear mixed-effects models and Cox proportional hazards model.

RESULTS

Among 164,853 eligible children aged 7.21 (0.74) years, 89,190 (54.1%) were boys. Our results showed that average systolic and diastolic BP increased by 0.48 and 0.42 standard deviations, respectively, over the 3-year follow-up. We identified 23,225 new cases of prehypertension and 35,067 of hypertension status. An interquartile range increase both in home-, school- and home-school NDVI100m was significantly associated with a reduction of 0.018-0.037 in BP z-scores and a 2.7%-7.6% lower risk of hypertension. Additionally, family socioeconomic status modified the impact of home-school greenness on BP levels. Air pollution exhibited mediating effects solely in school-greenness-BP associations, while physical activity and children's BMI mainly mediated the relationships between home-greenness and BP.

CONCLUSION

The findings of this large cohort study suggest that surrounding greenspaces are associated with lower BP levels and a decreased risk of prehypertension and hypertension in Chinese schoolchildren.

Associations of central precocious puberty with blood pressure trajectories: prospective cohort study

BACKGROUND

Sex differences in blood pressure (BP) appear during childhood and adolescence, but the role of central precocious puberty (CPP) remains unclear. In this study, we aimed to examine the association of CPP with the risk of early hypertension and BP trajectories in girls and boys.

METHODS

We analyzed trajectories of BP before and after puberty in girls aged 6-13 years (n = 305) and boys aged 10-15 years (n = 153) in the Taiwan Pubertal Longitudinal Study. The timing of puberty onset was defined as the month at which the children reached Tanner stage 2. We examined the association of CPP with the risk of early hypertension and BP trajectories before and after puberty onset.

RESULTS

Among boys, CPP was found to be associated with early hypertension (odds ratio, 7.45 [95% CI, 1.15-48.06]), whereas no such association was observed among girls. Boys with CPP had higher systolic BP than did those with normal puberty onset before puberty onset (mean difference, 6.51 [95% CI, 0.58-12.43]) and after puberty onset (mean difference, 8.92 [95% CI, 8.58-15.26]).

CONCLUSION

A large proportion of the higher systolic BP observed in boys with CPP compared with in those with normal puberty onset is accrued after puberty.

IMPACT

We examined the sex-specific association of central precocious puberty with blood pressure trajectories to better understand whether central precocious puberty was associated with early hypertension. Central precocious puberty was associated with differences in systolic blood pressure trajectories, especially after puberty onset in boys. For boys only, central precocious puberty was associated with early hypertension. A large proportion of the higher systolic blood pressure observed in boys with central precocious puberty compared with in those with normal puberty onset was accrued after puberty. Interventions targeting central precocious puberty are likely to influence systolic blood pressure in early adulthood.

Source apportionment of heavy metals in PM2.5 samples and effects of heavy metals on hypertension among schoolchildren in Tianjin

The prevalence of hypertension in children has increased significantly in recent years in China. The aim of this study was to provide scientific support to control ambient heavy metals (HMs) pollution and prevent childhood hypertension. In this study, ambient HMs in PM2.5 were collected, and 1339 students from Tianjin were randomly selected. Positive matrix factorization (PMF) was used to identify and determine the sources of HMs pollution. The generalized linear model, Bayesian kernel machine regression (BKMR) and the quantile g-computation method were used to analyze the relationships between exposure to HMs and the risk of childhood hypertension. The results showed that HMs in PM2.5 mainly came from four sources: soil dust, coal combustion, incineration of municipal waste and the metallurgical industry. The positive relationships between As, Se and Pb exposures and childhood hypertension risk were found. Coal combustion and incineration of municipal waste were important sources of HMs in the occurrence of childhood hypertension. Based on these accomplishments, this study could provide guidelines for the government and individuals to alleviate the damaging effects of HMs in PM2.5. The government must implement policies to control prime sources of HMs pollution.

Trend of blood pressure changes among children from 2012 to 2022: findings from student health surveillance in Eastern China

OBJECTIVES

The primary objective of this study is to examine the secular trends in blood pressure levels from 2012 to 2022 in eastern China. Additionally, to compare two standards [International Blood Pressure Reference for Children and Adolescents (ICBP) and the National Blood Pressure Reference for Chinese Han Children and Adolescents (CCBP)], we calculate the 95th percentile of blood pressure levels for students in developed regions (ECCBP). Secondly, the study aims to investigate potential contributors to elevated blood pressure, including sex, age, behaviors, and mental health. Lastly, the study seeks to estimate the total population aged 7-18 years with elevated blood pressure in Eastern China based on three references.

METHODS

The data used in this study were obtained from the Student Health Surveillance program in Jiangsu Province, which has been collecting data since 2012. Trained project members, skilled nurses, and doctors measured anthropometric variables. Additionally, online student questionnaires were administered in 2017, 2019, and 2021 to collect personal information behavior patterns, and mental health.

RESULTS

The study examined blood pressure changes in 123 013 children and adolescents in Eastern China from 2012 to 2022. Significant increases were observed in systolic blood pressure (SBP) and pulse pressure difference. Prevalence of elevated blood pressure followed a similar trend with ECCBP and CCBP, ranging from 17.2%/16.3% (2012-2015) to 11.6%/14.6% (2020-2022). Notably, BP with ICBP showed a significant increase in both prevalence and population, from 12.6% [6 713 679, 95% confidence interval (CI): 6 708 931 to 6 718 427] to 14.5% (7 004 208, 95% CI: 6 999 411 to 7 009 004). The study further emphasizes the significant impact of various risk factors on elevated blood pressure among children and adolescents, particularly the detrimental effect of depression on blood pressure, with the odds ratios (OR) in 2021 being 1.310 (95% CI, 1.290-1.330) for ECCBP, 1.239 (95% CI, 1.223-1.255) for CCBP, and 1.189 (95% CI, 1.176-1.202) for ICBP.

CONCLUSION

The study revealed significant changes in the population and prevalence of elevated blood pressure in Eastern China from 2012 to 2022. The findings indicate a decline in the prevalence of elevated blood pressure (referred to as CCBP or ECCBP), while highlighting an increasing trend in elevated blood pressure (referred to as ICBP). Untreated high blood pressure can lead to serious cardiovascular diseases in adulthood, underscoring the importance of early prevention and management, particularly through nonpharmacological methods and regular monitoring for students in Eastern China. Raising awareness among educators, parents, and healthcare providers about the association between mental health and elevated blood pressure is essential.

Reference blood pressure values obtained using the auscultation method for 2-year-old Japanese children: from the Japan Environment and Children's Study

BACKGROUND

Reference blood pressure (BP) values for Japanese children based on a large number of measurements by auscultation have not yet been established.

METHODS

This was a cross-sectional analysis of data from a birth-cohort study. The data from the sub-cohort study conducted for children at the age of 2 years in the Japan Environment and Children's Study from April 2015 to January 2017 were analyzed. BP was measured via auscultation using an aneroid sphygmomanometer. Each participant was measured in triplicate, and the average value of two consecutive measurements with a difference of less than 5 mmHg was recorded. The reference BP values were estimated using the lambda-mu-sigma (LMS) method and compared with those obtained via the polynomial regression model.

RESULTS

Data from 3361 participants were analyzed. Although the difference between the estimated BP values by the LMS and the polynomial regression model was small, the LMS model was more valid based on the results of the fit curve of the observed values and regression models for each model. For 2-year-old children with heights in the 50th percentile, the 50th, 90th, 95th, and 99th percentile reference values of systolic BP (mmHg) for boys were 91, 102, 106, and 112, and that for girls were 90, 101, 103, and 109, respectively, and those of diastolic BP for boys were 52, 62, 65, and 71, and that for girls were 52, 62, 65, and 71, respectively.

CONCLUSION

The reference BP values for 2-year-old Japanese children were determined based on auscultation and were made available.

Insulin resistance is more frequent in type 1 diabetes patients with long disease duration

AIMS

To investigate the clinical status of insulin resistance (IR) and its correlation with disease duration in patients with type 1 diabetes (T1D).

MATERIALS AND METHODS

Cross-sectional data from a T1D cohort were obtained (n = 923). IR-related metabolic disorders including hypertension, obesity, and dyslipidemia were used as outcome variables to explore the cut-off point for estimated glucose disposal rate (eGDR) by restricted cubic spline (RCS) curve. Regression models were used for multivariate analysis of the clinical factors associated with IR. The correlation between the status of IR and diabetes duration was depicted with the RCS curve.

RESULTS

IR-related metabolic disorders were observed in 39.4% of patients, with 9.1% meeting the criteria for metabolic syndrome. Specifically, patients with ≥10 years of T1D were more likely to have IR-related metabolic disorders (54.7% vs. 36.9%, p < 0.05). The presence of IR, defined as an eGDR ≤9.0 mg/kg/min, was observed in 42.2% of patients. Patients with IR had a longer diabetes duration (3.5 vs. 2.7, years, p = 0.003) and higher insulin dose (0.5 vs. 0.4, units per kg per day, p < 0.001). Moreover, the presence of IR showed a gradual increase during 10 years' disease duration and further analysis showed that diabetes duration ≥10 years was a key element behind the development of IR and IR-related metabolic disorders.

CONCLUSIONS

The status of IR is common in T1D patients, especially in those with ≥10 years of disease duration. Therapies targeting balancing glycaemic control and IR are needed to decrease the future risk of cardiovascular diseases in T1D.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT03610984 (cohort study of patients with type 1 diabetes).

Hypertension as a Novel Link for Shared Heritability in Age at Menarche and Cardiometabolic Traits

CONTEXT

Extremely early age at menarche, also called precocious puberty, has been associated with various cardiometabolic traits, but their shared heritability remains unclear.

OBJECTIVES

This work aimed to identify new shared genetic variants and their pathways for age at menarche and cardiometabolic traits and to investigate the influence of central precocious puberty on childhood cardiometabolic traits.

METHODS

Using the conjunction false discovery rate method, this study analyzed genome-wide association study data from the menarche-cardiometabolic traits among 59 655 females of Taiwanese ancestry and systemically investigated pleiotropy between age at menarche and cardiometabolic traits. To support the novel hypertension link, we used the Taiwan Puberty Longitudinal Study (TPLS) to investigate the influence of precocious puberty on childhood cardiometabolic traits.

RESULTS

We discovered 27 novel loci, with an overlap between age at menarche and cardiometabolic traits, including body fat and blood pressure. Among the novel genes discovered, SEC16B, CSK, CYP1A1, FTO, and USB1 are within a protein interaction network with known cardiometabolic genes, including traits for obesity and hypertension. These loci were confirmed through demonstration of significant changes in the methylation or expression levels of neighboring genes. Moreover, the TPLS provided evidence regarding a 2-fold higher risk of early-onset hypertension that occurred in girls with central precocious puberty.

CONCLUSION

Our study highlights the usefulness of cross-trait analyses for identifying shared etiology between age at menarche and cardiometabolic traits, especially early-onset hypertension. The menarche-related loci may contribute to early-onset hypertension through endocrinological pathways.

Weight self-misperception and obesity-related knowledge, attitudes, lifestyle behaviours and cardio-metabolic markers among Chinese school-aged children and adolescents

OBJECTIVE

The relationships between childhood weight self-misperception and obesity-related factors particularly health markers have not been extensively discussed. This study aims to examine the associations between weight self-misperception and obesity-related knowledge, attitudes, lifestyles and cardio-metabolic markers among Chinese paediatric population.

DESIGN

Cross-sectional study.

SETTING

Data sourced from a national survey in Chinese seven provinces in 2013.

PARTICIPANTS

Children and adolescents aged 5-19 years.

RESULTS

Of the total 14 079 participants, there were 14·5 % and 2·2 % participants over-estimated and under-perceived their weight, respectively. Multi-variable logistic regression was applied to calculate OR and 95 % CI (95 % Cl) of obesity-related behaviours and cardio-metabolic markers by actual and perceived weight status. Individuals who perceived themselves as overweight/obese were more likely to have prolonged screen time, insufficient dairy intake and over sugar-sweetened beverages consumption (all P < 0·05), regardless of their weight. Furthermore, actual overweight/obese individuals had higher odds of abnormal cardio-metabolic markers, but a smaller magnitude of association was found among weight under-estimators. Among non-overweight/obese individuals, weight over-estimation was positively associated with abdominal obesity (OR: 10·49, 95 % CI: 7·45, 14·76), elevated blood pressure (OR: 1·30, 95 % CI: 1·12, 1·51) and dyslipidemia (OR: 1·43, 95 % CI: 1·29, 1·58).

CONCLUSIONS

Weight over-perception was more prevalent than under-estimation, particularly in girls. Weight over-estimators tended to master better knowledge but behave more unhealthily; both weight over-perception and actual overweight/obesity status were associated with poorer cardio-metabolic markers. Future obesity intervention programmes should additionally pay attention to the population with inaccurate estimation of weight who were easily overlooked.

Association of SO2/CO exposure and greenness with high blood pressure in children and adolescents: A longitudinal study in China

Introduction

We aimed to investigate the association between greenness around schools, long-term gaseous air pollution exposure (SO₂ and CO), and blood pressure in children and adolescents.

Methods

From 2006 to 2018, a total of 219,956 Chinese children and adolescents aged 7-17 years in Beijing and Zhongshan were included in this longitudinal study. Annual average concentrations of SO₂ and CO and the mean values of normalized difference vegetation index around schools were calculated. We used the generalized estimation equation model, restricted cubic spline model, and Cox model to analyze the health effects.

Results

Among all the subjects, 52,515 had the first onset of HBP. During the follow-up, HBP's cumulative incidence and incidence density were 23.88% and 7.72 per 100 person-year respectively. Exposures to SO₂ and CO were significantly associated with SBP [β = 1.30, 95% CI: (1.26, 1.34) and 0.78 (0.75, 0.81)], DBP [β = 0.81 (0.79, 0.84) and 0.46 (0.44, 0.48)] and HBP [HR = 1.58 (1.57, 1.60) and 1.42 (1.41, 1.43)]. The risks of HBP attributed to SO₂ and CO pollution would be higher in school-aged children in the low greenness group: the attributable fractions (AFs) were 26.31% and 20.04%, but only 13.90% and 17.81% in the higher greenness group. The AFs were also higher for normal-BMI children and adolescents in the low greenness group (AFs = 30.90% and 22.64%, but 14.41% and 18.65% in the high greenness group), while the AFs were not as high as expected for obese children in the low greenness group (AFs = 10.64% and 8.61%), nor was it significantly lower in the high greenness group (AFs = 9.60% and 10.72%).

Discussion

Greenness could alleviate the damage effects of SO₂/CO exposure on the risks of HBP among children and adolescents, and the benefit is BMI sensitivity. It might offer insights for policymakers in making effective official interventions to prevent and control the prevalence of childhood HBP and the future disease burden caused by air pollution.

Associations between sleep characteristics and risk for high blood pressure among students aged 9-18: A cross-sectional study in China

OBJECTIVE

The aim was to investigate the association of multidimensional sleep indicators with high blood pressure (HBP) of Chinese students.

METHODS

Participants in this cross-sectional study included 11561 students aged 9-18. Sleep was characterized by sleep timing (e.g., bedtime), sleep duration and sleep consistency (e.g., bedtime/wake-up time deviations and social jet lag (SJL)). We used odds ratios (OR) and 95% confidence intervals (95% CI) to assess the relationship between sleep and HBP.

RESULTS

Primary school students who slept 8.00-9.00h had a lower risk of HBP compared with sleeping >10h (OR 0.370, 95%CI 0.208, 0.658), while junior middle school students reporting ≤8.00h on weekday night had a lower risk of HBP compared with sleeping >10h (OR 0.303, 95%CI 0.111, 0.829). Moreover, compared with deviations = 0h, the OR (95%CI) for wake-up time deviations <0h and bedtime deviations >0h in primary school students with HBP were 0.314 (0.125, 0.790) and 2.155 (1.205, 3.853). Furthermore, compared with SJL = 0h, senior high school students reporting SJL = 0.01-0.50h, SJL = 0.51-1.00h and SJL = 1.01-2.00h had greater risk of HBP (OR 1.566, 95%CI 1.039, 2.361; OR 1.760, 95%CI 1.177, 2.631; OR 1.660, 95%CI 1.124, 2.452, respectively). Bedtime at night was associated with HBP for three educational periods students, however, there was no significant association between mid-day nap and HBP.

CONCLUSIONS

Sleep timing, sleep duration and sleep consistency are associated with high blood pressure in children and adolescents.

Systolic and diastolic left ventricular function in children with primary hypertension: a systematic review and meta-analysis

OBJECTIVE

Evaluation of left ventricular function provides early evidence of target-organ damage in children with primary hypertension. We performed a systematic review and meta-analysis of left ventricular systolic and diastolic function in children and adolescents with primary hypertension.

METHODS

Literature search was performed in PubMed database and out of 718 articles (published between 2000 and 2021) 22 studies providing comparison of left ventricular function parameters between children with primary hypertension and normotensive controls were selected.

RESULTS

Overall, 3460 children (5-21 years) with primary hypertension were analyzed. Meta-analysis showed that hypertensive patients when compared with normotensives, had an increased heart rate (mean difference [MD] 5.59; 95% confidence interval [CI] 3.28, 7.89; 10 studies) and increased fractional shortening (MD 1.04; 95% CI 0.48, 1.60; 9 studies) but did not differ in ejection fraction (MD -0.03; 95% CI -1.07, 1.02; 12 studies). Stroke volume was higher in one out of three studies, whereas no differences in cardiac output were found in two studies with available data. Hypertensive children had also lower E/A values (MD -0.21; -0.33, -0.09; 14 studies), greater values of E/e' (MD 0.59; 0.36, 0.82; 8 studies) and greater global longitudinal stress (MD 2.50; 2.03, 2.96; 4 studies) when compared to those with normotension.

CONCLUSION

Our results indicate that hypertensive children and adolescents present with signs of hyperkinetic function of the left ventricle, demonstrate evidence of increased left ventricular strain and impaired diastolic function compared to normotensive controls.

Comparisons of tri-ponderal mass index and body mass index in discriminating hypertension at three separate visits in adolescents: A retrospective cohort study

OBJECTIVE

To estimate whether the new obesity indicator tri-ponderal mass index (TMI) has a better capacity to predict adolescent hypertension (HTN) and HTN subtypes at three separate blood pressure (BP) visits than the conventionally used body mass index (BMI).

METHODS

A total of 36,950 adolescents who had initial normal BP from 2012 to 2019 were included in Suzhou, China. HTN was defined as having three separate visits of elevated BP in 2020. The area under the receiver-operating characteristic curve (AUC), false-positive rate, false-negative rate, total misclassification rates, net reclassification improvement (NRI), and integrated discrimination improvement were calculated to compare the discriminative ability of HTN between BMI and TMI.

RESULTS

TMI had better predictive abilities than BMI among all of the participants when predicting HTN (difference in AUC = 0.019, 95% CI = 0.007-0.031; NRI = 0.067, 95% CI = 0.008-0.127) and isolated systolic hypertension (difference in AUC = 0.021, 95% CI = 0.005-0.036; NRI = 0.106, 95% CI = 0.029-0.183). The difference in prediction abilities between BMI and TMI was more obvious in the subgroup of age ≥16. Also, TMI outperformed BMI in predicting adolescent HTN in girls but not in boys.

CONCLUSION

Compared with BMI, TMI may have a better predictive capacity for HTN, particularly in girls and older adolescents. TMI has the potential to be used as an effective predictor for HTN in clinic practice. Further studies are needed to verify the utility of TMI.

Prevalence trends of hypertension and influence factors among children and adolescents aged 7-17 years in China, 2011-2015: A serial cross-sectional study

Hypertension has rapidly increased in the last decades throughout the world. It is an emerging disease. However, limited information is available on secular trends and factors of childhood and adolescents' hypertension in China. In this study, 5-year successive data were derived from a cross-sectional study of the China Health and Nutrition Survey (CHNS) in 2011 and 2015. We used systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) at least 95th percentile on the basis of age, sex, and height percentiles to define hypertension (HBP). A total of 2,827 children and adolescents aged 7-17 years were included. The age-standardized prevalence of hypertension was increased significantly across 5 years: the standardized prevalence of hypertension was increased from 8.08% (2011) to 11.46% (2015) in China (P < 0.01). The mean SBP of boys increased from 101.21 to 102.79 mmHg, while the mean SBP of girls increased from 98.96 to 100.04 mmHg. The mean DBP of boys increased from 61.20 to 67.40 mmHg, while the mean DBP of girls increased from 64.34 to 65.76 mmHg. The prevalence of hypertension grew continuously in both sexes, but the pace of change for boys was more rapid than that for girls. This study confirmed that the association between rural (odds ratio [OR] = 1.394, 95%CI 1.032-1.883), overweight/obesity (OR = 2.621, 95%CI 1.506-4.562), and BP levels was highly correlated (P < 0.05). The possible protecting factors associated with hypertension were being a girl (OR = 0.788, 95%CI 0.595-1.043). There was no association between weekly physical activity, daily sleep duration, and hypertension (P > 0.05). Further in-depth analysis of influencing factors and comprehensive interventions should be urgently implemented to combat the hypertension epidemic among children and adolescents in China.

Endogenous sex hormones homeostasis disruption combined with exogenous phthalates exposure increase the risks of childhood high blood pressure: A cohort study in China

BACKGROUND

The structural similarity between sex hormones and exogenous phthalates (PAEs) enabled them as disrupters in regulating childhood blood pressure (BP). We aim to explore the association of sex hormones homeostasis and PAEs metabolites with childhood high BP (HBP).

METHODS

A cohort study was conducted with 1416 children aged 7-13 years at baseline and with 824, 819, and 801 children completing three waves' follow up. Serum testosterone (TT) and estradiol (E2) in children during three consecutive waves of surveys were measured by radioimmunoassay, and then TT/E2 ratio calculated as TT divided by E2 were used to represent sex hormones homeostasis. Seven urinary PAEs metabolites were measured in children of first wave. The BP Z-Scores and HBP across waves were obtained by sex, age, and height specific percentiles. Log-binomial regression models with adjusted risk ratios (aRR) after adjusting for confounders were utilized.

RESULTS

The prevalence of HBP at the baseline survey was 25.5%, and increased from 26.3% in the first wave of survey to 35.0% in the third wave of survey. PAEs were negatively correlated with E2, while positively correlated with TT and TT/E2 ratio. A positive association of the serum TT levels, TT/E2 ratio, and total PAEs was found with HBP prevalence (in wave 1, 2 and 3 with TT (aRR): 1.63, 1.37 and 1.45; with TT/E2: 1.63, 1.42 and 1.20; with PAEs: 1.40, 1.32 and 1.32), persistent HBP (with TT (aRR): 2.19; TT/E2: 2.16; PAEs: 2.57), occasional HBP (with TT (aRR): 1.94; TT/E2: 1.72; PAEs: 1.38), and new HBP incidence (with TT (aRR): 1.44; TT/E2: 1.57; PAEs: 1.67), but E2 had a negative association with HBP phenotypes (HBP prevalence in wave 1, 2 and 3 (aRR): 0.77, 0.93, and 1.10; persistent HBP: 0.47; occasional HBP: 0.96; new HBP incidence: 0.81). The E2 and PAEs had antagonistic effects on HBP risks in children, particularly in girls and those with high BMI group, but the TT levels, TT/E2 ratio and PAEs had synergistic effects on HBP risks in children, particularly in boys and those with high BMI group.

CONCLUSION

Exogenous PAEs exposure and endogenous sex hormones homeostasis disruption independently increase the risks of HBP. Moreover, the exogenous PAEs exposure could disrupt the endogenous sex hormones homeostasis in children, thereby combinedly increased risks of childhood HBP.

Trends in associations between socioeconomic development and urban-rural disparity with high blood pressure in Chinese children and adolescents over two decades

This study aimed to assess the association between the trend of urban-rural disparity in high blood pressure (HBP) in Chinese children and adolescents and socioeconomic development. Data on 1,054,602 students aged 7-18 years were obtained from five successive national surveys administered in 29 Chinese provinces in 1995, 2000, 2005, 2010, and 2014. HBP was defined as average measured systolic BP and/or diastolic BP equal to or more than 95th percentile. The socioeconomic indicators at the provincial-level included gross domestic product (GDP) per capita, the Engel coefficient, and urbanization rates. From 1995 to 2014, HBP prevalence in Chinese children and adolescents fluctuated between 6.9% and 9.2%. Rural areas had a higher prevalence of HBP than urban areas, with a diminishing trend in urban-rural disparity from 1995 to 2010 with a reduced OR from 1.45 (95% CI: 1.40-150) in 1995 to 1.09 (1.05-1.12) in 2010, whereas a widening gap in 2014 with OR of 1.23 (1.19-1.26)). A positive association existed between the improvement of socioeconomic indicators and the increase in HBP, which was demonstrated obviously by the Engel coefficient strata. The increases in the urbanization rates were accompanied by a greater increase of HBP in urban than in rural areas. The large urban-rural disparity suggests a priority of HBP control in rural children due to their current and future HBP and cardiovascular disease risks. Socioeconomic development could affect the urban-rural disparity in HBP risk, reflecting the importance of effective policy responses for preventing HBP by avoiding unhealthy lifestyles brought about by rapid economic development.

Change of weight status during school age and its association with late adolescent blood pressure: Results from a 15-year longitudinal study in China

Background

Change in obesity risk could be related to shift in high blood pressure (HBP) risk, while individualized influence of weight change on high blood pressure is in need of exploration.

Methods

A total of 16,446 children (53.47% boys) and 13,9021 effective annual measurements from 2006 to 2020 were recruited. Children's weight status, both at baseline and endpoint, was categorized as underweight, normal, overweight, and obese according to the age and sex-specific Body Mass Index z scores. HBP at late adolescence was defined with the last two measurements for each child. Populational attributable risk (PAR) of weight trait on HBP risk was calculated.

Results

Compared to children who maintained normal weight during follow-up, staying obese was associated with the highest HBP risk with OR of 6.39 (95% CI: 4.46, 9.15; p < 0.001) and PAR of 28.71% (95% CI: 21.58, 35.54) in boys, and OR of 6.12 (95% CI: 2.80, 13.37; p < 0.001) and PAR of 12.75% (95% CI: 4.29, 21.02) in girls. Returning from obese to normal weight was associated with lowered HBP risk, with ORs of 1.07 (95% CI: 0.69, 1.66; p = 0.771) in boys and 0.73 (95% CI: 0.25, 2.12; p = 0.566) in girls.

Conclusion

Weight loss program could be effective to reduce HBP risk during school age, while the underlying mechanism needs further exploration.

Co-exposure to priority-controlled metals mixture and blood pressure in Chinese children from two panel studies

Metals may affect adversely cardiovascular system, but epidemiological evidence on the associations of priority-controlled metals including antimony (Sb), arsenic (As), cadmium, lead, and thallium with children's blood pressure (BP) was scarce and inconsistent. We conducted two panel studies with 3 surveys across 3 seasons among 144 and 142 children aged 4-12 years in Guangzhou and Weinan, respectively. During each seasonal survey, urine samples were collected for 4 consecutive days and BP was measured on the 4th day. We obtained 786 BP values and urinary metals measurements at least once within 4 days, while 773, 596, 612, and 754 urinary metals measurements were effective on the health examination day (Lag 0), and the 1^st, 2^nd, and 3^rd day preceding BP measurement (Lag 1, lag 2 and lag 3), respectively. We used linear mixed-effect models, generalized estimating equations and multiple informant models to assess the associations of individual metal at each lag day and accumulated lag day (4 days averaged, lag 0-3) with BP and hypertension, and Bayesian Kernel Machine Regression to evaluate the relations of metals mixture at lag 0-3 and BP outcomes. We found Sb was positively and consistently related to systolic BP (SBP), mean arterial pressure (MAP), and odds of having hypertension within 4 days, which were the strongest at lag 0 and declined over time. And such relationships at lag 0-3 showed in a dose-response manner. Meanwhile, Sb was the only contributor to the relations of mixture with SBP, MAP, and odds of having hypertension. Also, synergistic interaction between Sb and As was significant. In addition, modification effect of passive smoking status on the association of Sb and SBP was more evident in passive smokers. Accordingly, urinary Sb was consistently and dose-responsively associated with increased BP and hypertension, of which Sb was the major contributor among children.

The compatibility of new blood pressure reference values for Korean children and adolescents with the US reference: the Korean Working Group of Pediatric Hypertension

Background

Childhood hypertension is associated with hypertension and metabolic syndrome in adulthood. Since the definition of childhood hypertension is based on the distribution of normative blood pressure (BP), a reference range is essential to create hypertension guidelines for children. We aimed to investigate the compatibility of the new Korean BP reference with the United States (US) BP reference based on the 2017 Clinical Practice Guideline.

Methods

We compared the new Korean reference BP values for children and adolescents aged 10 to 17 years with those in the 2017 Clinical Practice Guidelines. We also analyzed the differences in the prevalence of hypertension in Korean children and adolescents when reference value was applied. Considering Korean and US BP references together, linear trend lines were sought.

Results

Systolic BP (SBP) and diastolic BP (DBP) values in 95th percentiles showed no significant differences between the two BP references. Applying the two reference values, there was no significant difference in the prevalence of elevated BP and a combination of elevated BP and hypertension. Combining the Korean and US BP values and plotting them against age, approximate lines for the 90th and 95th SBP and DBP percentiles were observed.

Conclusions

The BP values of the new Korean BP reference were similar to those of the US BP reference; they were reliable and interchangeable.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40885-022-00200-x.

Development and Validation of a Nomogram-Based Prognostic Model to Predict High Blood Pressure in Children and Adolescents—Findings From 342,736 Individuals in China

Objectives

Predicting the potential risk factors of high blood pressure (HBP) among children and adolescents is still a knowledge gap. Our study aimed to establish and validate a nomogram-based model for identifying youths at risk of developing HBP.

Methods

HBP was defined as systolic blood pressure or diastolic blood pressure above the 95th percentile, using age, gender, and height-specific cut-off points. Penalized regression with Lasso was used to identify the strongest predictors of HBP. Internal validation was conducted by a 5-fold cross-validation and bootstrapping approach. The predictive variables and the advanced nomogram plot were identified by conducting univariate and multivariate logistic regression analyses. A nomogram was constructed by a training group comprised of 239,546 (69.9%) participants and subsequently validated by an external group with 103,190 (30.1%) participants.

Results

Of 342,736 children and adolescents, 55,480 (16.2%) youths were identified with HBP with mean age 11.51 ± 1.45 years and 183,487 were boys (53.5%). Nine significant relevant predictors were identified including: age, gender, weight status, birth weight, breastfeeding, gestational hypertension, family history of obesity and hypertension, and physical activity. Acceptable discrimination [area under the receiver operating characteristic curve (AUC): 0.742 (development group), 0.740 (validation group)] and good calibration (Hosmer and Lemeshow statistics, P > 0.05) were observed in our models. An available web-based nomogram was built online on https://hbpnomogram.shinyapps.io/Dyn_Nomo_HBP/.

Conclusions

This model composed of age, gender, early life factors, family history of the disease, and lifestyle factors may predict the risk of HBP among youths, which has developed a promising nomogram that may aid in more accurately identifying HBP among youths in primary care.

Greenness alleviates the effects of ambient particulate matter on the risks of high blood pressure in children and adolescents

Both ambient particulate matter (PM) and decrease of greenness have been suggested as risk factors for high blood pressure (HBP) in children and adolescents. But most evidence were from cross-sectional studies with limited data from prospective cohorts. In this cohort study, we included 588,004 children and adolescents aged 7 to 18 years without HBP from 2005 to 2018 in Beijing (240,081) and Zhongshan (347,923) city of China. The cumulative incidence of HBP was 32.04%, and incidence rate was 14.86 per 100 person-year. After adjustment for confounders, the ten-unit increase in PM₁, PM_2.5, and PM₁₀ exposure was significantly associated with 43%, 70%, and 43%- higher risks of HBP, respectively, but the 0.1-unit increase in NDVI exposure was significantly associated with a 25% lower risk of HBP. The HRs of PM₁ on the HBP risk were 1.486 and 1.150 in the low and the high-level of greenness, and they were 2.635 and 2.507 for PM_2.5, and for PM₁₀ 1.367 and 1.702 in the two groups. The attributable fraction (AFs) of PM₁, PM_2.5, and PM₁₀ on HBP incidents were 13.74%, 40.08%, and 15.47% in the low-level of greenness, which simultaneously was higher than those in the high-level of greenness (AF = 4.62%, 17.28%, and 9.96%). The exposure to higher ambient PM air pollution and lower greenness around schools were associated with a higher risk of HBP in children and adolescents, but higher greenness alleviated the adverse effects of ambient PM₁ and PM_2.5 on the HBP risks. Our findings highlighted a synergic strategy in preventing childhood HBP by decreasing air pollution reduction and improving greenness concurrently.

Long-term effects of PM2.5 components on blood pressure and hypertension in Chinese children and adolescents

Growing evidence has linked fine particulate matter (PM_2.5) exposure to elevated blood pressure, but the effects of PM_2.5 components are unclear, particularly in children and adolescents. Based on a cross-sectional investigation in China, we analyzed the associations between long-term exposure to PM_2.5 and its major components with elevated blood pressure in children and adolescents. A representative sample (N = 37,610) of children and adolescents with age 7-18 years was collected in seven Chinese provinces. Exposures to PM_2.5 and five of its major components, including black carbon (BC), organic matter (OM), inorganic nitrate (NO₃^-), sulfate (SO₄^2-), and soil particles (SOIL), were estimated using satellite-based spatiotemporal models. The associations between long-term exposures to PM_2.5 and its components and diastolic blood pressure (DBP), systolic blood pressure (SBP), and hypertension were investigated using mixed-effects logistic and linear regression models. Within the populations, 11.5 % were classified as hypertension. After adjusting for a variety of covariates, per interquartile range (IQR) increment in PM_2.5 mass and BC levels were significantly associated with a higher hypertension prevalence with odds ratios (ORs) of 1.56 (95% confidence interval (CI): 1.08, 2.25) for PM_2.5 and 1.19 (95% CI: 1.04, 1.35) for BC. Long-term exposures to PM_2.5 and BC have also been associated with elevated SBP and DBP. Additionally, OM and NO₃^- were significantly associated with increased SBP, while SOIL was significantly associated with increased DBP. In the subgroup analysis, the associations between long-term exposures to BC and blood pressure vary significantly by urbanicity of residential area and diet habits. Our study suggests that long-term exposure to PM_2.5 mass and specific PM_2.5 components, especially for BC, are significantly associated with elevated blood pressure and a higher hypertension prevalence in Chinese children and adolescents.

Multilevel Analysis of the Nutritional and Health Status among Children and Adolescents in Eastern China

We aimed to identify multiple nutritional health problems and the relevant factors among children and adolescents aged 7–17 years. This study was part of the China Nutrition and Health Surveillance of Children and Lactating Mothers in 2016–2017, conducted in Jiangsu Province in eastern China. After sampling, 3025 school-age children and adolescents were enrolled into this study. Demographic information collections and anthropometric measurements were conducted by trained local Center for Disease Control and Prevention (CDC) staff. Venous blood in the amount of 6 mL was drawn from each participant in the morning and used for testing biochemical and nutritional indicators. Multivariate logistic regression analysis and Poisson regression analysis were used for overnutrition- and undernutrition-related disorders to test relevant personal, parental, and household factors. The prevalence of wasting, overweight, and obesity was 5.5%, 14.8%, and 12.7%, respectively. Metabolic syndrome (MetS) was prevalent among 5.1% of participants. Among the study participants, 29.5% had hyperuricemia. The overall prevalence of high low-density lipoprotein (LDL) and high total cholesterol (TC) of all participants was 4.8% and 7.4%, respectively. 0.9% of the participants had vitamin A deficiency (VAD) and 14.6% had marginal vitamin A deficiency; 25.1% had vitamin D deficiency (VDD) and 54.5% had inadequate vitamin D levels. Anemia was present in 4.0% of all participants. The prevalence of zinc deficiency was 4.8%. Demographic characteristics, behavioral characteristics, parents’ characteristics, and family characteristics were associated with these multiple malnutrition disorders. The double burdens of malnutrition, which includes overnutrition- and undernutrition-related diseases, were prevalent among the school-age children and adolescents in Jiangsu Province in eastern China. There were various factors related to different nutritional problems. Thus, health education focusing on behavior intervention and nutrition education are necessary in containing nutritional problems among children.

Associations between Serum Vitamin A and Metabolic Risk Factors among Eastern Chinese Children and Adolescents

Vitamin A, a fat-soluble essential vitamin, is implicated in a large range of physiological processes. Up to now, the associations between vitamin A and metabolic syndrome (MetS) or other metabolic risk factors are controversial in children and adolescents. Thus, we aimed to dig into the relationship of vitamin A with MetS and many other metabolic risk factors. This was a cross-sectional study derived from the China National Nutrition and Health Surveillance of Children and Lactating Mothers. A total of 3025 school-aged (7–17 years) children and adolescents were selected by applying multistage stratified cluster random sampling methods in the Jiangsu Province of eastern China. Through enquiry survey, anthropometric measurement and laboratory examination, relevant information and blood biochemical indexes of the participants were collected in this study. MetS was identified according to the modified criteria of the National Cholesterol Education Program–Adult Treatment Panel III (NCEP-ATP III). Multivariate logistic analysis and the generalized additive model (GAM) were used to analyze the relationship between vitamin A and various metabolic risk factors. The overweight, obesity and MetS prevalence of children and adolescents in this study was 14.0%, 11.9% and 5.1%, respectively. The risk of prevalent MetS, general obesity, high low-density lipoprotein (LDL), high total cholesterol (TC) and hyperuricemia increased with vitamin A in a dose-dependent way. Logistic regression analysis showed that serum vitamin A Z scores were positively associated with MetS and central obesity, elevated blood pressure (BP) and elevated triglyceride (TG). Sex stratification analysis showed that both in male and female participants, the risk of prevalent MetS, general obesity, high LDL, high TC and hyperuricemia still increased with vitamin A levels. MetS was at a high prevalence level in children and adolescents in Jiangsu that were 7–17 years old. Vitamin A was positively associated with obesity, MetS, dyslipidemia and hyperuricemia. More public health measures and new visions should focus on the effects of retinol on children and adolescents.

Percentile Curves for Multiple Physical Fitness Components Among Chinese Han Children and Adolescents Aged 7-18 Years From a National Survey Based on the Total and the Normal Weight Population

Introduction: To develop sex- and age-specific percentile curves for seven physical fitness components for Chinese Han children and adolescents aged 7–18 years based on the total and the normal weight population using a nationally representative sample.

Methods: A total of 214,228 Chinese Han children and adolescents aged 7–18 years old with all nutritional status and 161,999 with normal weight were examined. Seven physical fitness components [forced vital capacity (FVC), standing long jump (SLJ), 50-m dash, sit-and-reach (SR), grip strength (GS), body muscle strength (BMS), and endurance running (ER)] were measured, and percentile curves for each physical fitness component at the 20th, 40th, 60th, and 80th percentiles were calculated using the general additive model for location, scale, and shape (GAMLSS).

Results: Physical fitness presents different characteristics in each subgroup of sex, age, and nutritional status among children and adolescents. Sex- and age-specific percentiles for the seven physical fitness components among the Chinese Han children and adolescents aged 7–18 years based on the total and the normal weight population were provided as curves. Boys performed better than girls in FVC, SLJ, 50-m dash, GS, and ER but worse in SR. The performances of FVC, SLJ, 50-m dash, GS, BMS, and ER increased with age, but the estimates of SR were at the bottom among boys aged 12 years and girls aged 11 years. The annual increments of all components were larger in boys than girls at the peak time, which was earlier in girls than boys. The gap of physical fitness components between sexes increased with age, especially during puberty (since after 11 years old).

Conclusion: The present study described the percentile curves of seven physical fitness components among the Chinese Han children and adolescents based on the total and the normal weight population at the national level, which could help to chart the level of physical fitness across age span and identify the extreme populations with either health concerns or potential talents.

Prevalence of hypertension and related risk factors among children and adolescents at three separate visits: A large school-based study in China

OBJECTIVE

We aimed to demonstrate characteristics of hypertension at three separate visits and its risk factors among children and adolescents based on a large school-based study in China.

MATERIALS AND METHODS

Based on a large-scale ongoing monitoring program conducted in Suzhou, China, 59,679 children and adolescents aged 7-17 years from 60 public schools were enrolled during 2020 to 2021. Height, weight, and blood pressure (BP) were measured. Additional BP would be measured for hypertensive students at least 2 weeks later. Confirmed hypertension was defined as simultaneously BP meeting above or equal to 95th percentile for age, sex, and height at three separate visits. Odds ratio (ORs), and 95% CIs were calculated by logistic regression to identify risk factors for hypertension.

RESULTS

Prevalence of hypertension at three separate visits were 20.4, 6.3, and 3.1%, respectively. Prevalence of confirmed isolated systolic hypertension, isolated diastolic hypertension, and systolic and diastolic hypertension were 1.9, 0.3, and 0.9%, respectively. Hypertension prevalence for stages 1 and 2 were 2.6 and 0.6%. Different hypertension prevalence were found among various age and gender groups. Boys [OR, 1.137 (95% CI, 1.033-1.251)], high age [OR, 3.326 (95% CI, 2.950-3.751)], urban residents [OR, 1.579 (95% CI, 1.417-1.760)], high-socioeconomic status [OR, 1.156 (95% CI, 1.039-1.286)] and body mass index category including overweight [1.883 (95% CI, 1.665-2.129)], obesity [4.049 (95% CI, 3.625-4.523)], and thinness [OR, 0.457 (95% CI, 0.306-0.683)] were associated with confirmed hypertension.

CONCLUSION

A single BP measurement would overestimate hypertension prevalence, about 3% Chinese children were hypertensive, early, and effective intervention around risk factors for hypertension should be taken.

Association between serum zinc concentrations and metabolic risk factors among Chinese children and adolescents

The aim of the present study was to examine whether serum Zn concentrations were associated with metabolic risk factors in Chinese children and adolescents. This was a cross-sectional study including 3241 participants, aged 6 to 17 years, from Jiangsu, China. Metabolic risk factors included fasting glucose (FG), total cholesterol (TC), TAG, HDL-cholesterol, LDL-cholesterol, systolic blood pressure and diastolic blood pressure. Data were analysed using multi-variable linear regression and generalised additive models, which were adjusted for age, sex, high-sensitive C-reactive protein, estimated glomerular filtration rate, BMI and region of residence, to assess the associations of serum Zn concentrations with metabolic risk factors. We observed a negative association between serum Zn concentrations and FG (coefficient = -0·532; 95 % CI -0·569, -0·495; P < 0·001). Moreover, TC (coefficient = 0·175; 95 % CI 0·127, 0·222; P < 0·001), HDL-cholesterol (coefficient = 0·137; 95 % CI 0·082, 0·193; P < 0·001) and LDL-cholesterol (coefficient = 0·195; 95 % CI 0·128, 0·263; P < 0·001) were found to be positively associated with Zn levels. A generalised additive model showed that the negative association between serum Zn and FG was weak at lower serum Zn concentrations and was stronger with the increase in serum Zn concentrations. Additionally, a U-shaped association between serum Zn and TAG was observed. Serum Zn concentrations were associated with FG, TC, TAG, HDL-cholesterol and LDL-cholesterol levels in Chinese children and adolescents. Lower levels of serum Zn were more likely related to a poor metabolic status.

Comparison of China Reference with Different National and International References: The Prevalence of High Blood Pressure in 695,302 Children and Adolescents in a Metropolis of Yangtze River Delta, China

Objectives

This study aimed to compare performances of China reference and different national references on high blood pressure (HBP).

Methods

A cross-sectional study including 695,302 children and adolescents aged 7 to 17 years in Suzhou, China, was conducted to determine the prevalence of HBP based on U.S., international, Europe, and China references in 2016.

Results

Different percentiles of height and blood pressure were found among four references. Referring to U.S. reference, the prevalence of HBP was the highest with 26.0%, followed by International reference with 20.0%, Europe reference with 19.5%, and China reference with 19.2%. McNemar tests indicated statistically significant differences between HBP prevalence comparing China reference with the other 3 references (P < 0.001). The area under the curve was 0.947, 0.851, and 0.949 for U.S., international, and Europe reference, respectively. U.S. reference showed the highest sensitivity (98.2%), but the lowest specificity (91.2%), and Europe reference showed the highest kappa value (0.893).

Conclusions

The prevalence of HBP varied among these four references, and the appropriate choice of reference would be important to recognize high-risk children and judge the trends of HBP prevalence in the targeted population.

Hypertension in adolescents: The role of obesity and family history

We evaluated the combined effect of obesity and family history (FH) on the risk of hypertension in adolescents. We studied 1288 school‐aged adolescents aged 16.0 ± 0.5 years (49.0% males) attending the medical examination for enrollment in the city of Nanning, China. Their blood pressure, weight, and height were measured. A questionnaire was administered to both adolescents and their parents to obtain information on the participants’ medical history. Multiple logistic regression analysis, according to bodyweight categories and adjusted for age, gender, and body mass index (BMI), was done to determine the association of FH with hypertension. Hypertension was found in 14.1% of adolescents. The prevalence of hypertension was significantly higher in adolescents with obesity and positive FH than their normal weight and negative FH counterparts. For adolescents with normal weight and waist circumstance (WC), those with a positive FH in parents compared to those without had an significantly increased risk for hypertension (odds ratio [OR], 2.15; 95% confidence interval [CI] 1.28–3.61, and 1.96; 95% CI 1.16–3.32, respectively). These findings were adjusted for age, gender, and BMI. Our study showed that routine screening for pediatric hypertension should be performed in adolescents who are overweight and obese. Furthermore, parental FH of hypertension played an important role in predicting the hypertension phenotype among adolescents with normal weight.

Geographical Variation in Physical Fitness Among Chinese Children and Adolescents From 2005 to 2014

Introduction: To examine the geographical variation in change in the levels of physical fitness from 2005 to 2014 among Chinese children and adolescents.

Methods: A total of 663,813 children 7 to 18 years of age with physical fitness data in 2005, 2010 and 2014, participated in the study. Physical fitness was assessed using six components, and their standardized scores were aggregated to form a summary physical fitness indicator (PFI).

Results: Over the study period, there was an increase in the proportion of high PFI (from 15.3% in 2005 to 19.0% in 2014, P_trend < 0.05) and a decrease in the proportion of low PFI (from 30.6 to 29.8%, P_trend < 0.05). Children and adolescents in the eastern provinces of China showed a high proportion of high PFI with an increasing trend over time, while those in the western provinces had a high proportion of low PFI with a decreasing trend over time (P < 0.05).

Conclusions: The comprehensive physical fitness among Chinese children showed an improved trend from 2005 to 2014. Region-specific interventions with priority policies could be useful to sustainably narrow geographical variation in Chinese children, especially in the western provinces.

Individual-, Family-, and School-Level Ecological Correlates With Physical Fitness Among Chinese School-Aged Children and Adolescents: A National Cross-Sectional Survey in 2014

Introduction: Few studies have examined the association between the individual-, family-, and school-level ecological correlates and physical fitness among Chinese children and adolescents, which is the purpose of the present study. Methods: A total of 157,168 children and adolescents, 10-18 years of age, with physical fitness data in 2014, participated in the study. Physical fitness was assessed, using six tests: forced vital capacity, standing long jump, sit and reach, body muscle strength, 50-m dash, and endurance running. Scores were aggregated to form a summary physical fitness indicator (PFI), which was then classified into five levels: low, low-middle, middle, middle-high, and high. Each option of individual-, family-, and school-level measures were constructed into a positive or negative correlate of physical fitness and then accumulated as a composite ecological score. Results: Among the 20 individual-, family-, and school-level correlates, 18 were found to be significantly associated with PFI, with high PFI levels being correlated with the positive group of correlates and low PFI levels correlated with the negative group of correlates (p < 0.05). High scores of ecological correlates were associated with a high level of PFI [adjusted odds ratio (OR) = 1.06, 95% CI: 1.06, 1.07)] whereas low scores were associated with a low level of PFI (OR = 0.95, 95% CI:0.95, 0.95). The ecological correlates at the individual, school- and family-levels were shown to be significantly related to high PFI among Chinese children and adolescents aged 10-18 years with different ORs of 5.97 (95% CI: 5.51, 6.47), 3.94 (3.66, 4.24), and 1.25 (1.19, 1.31). The PAR% of 20 cumulative factors effects due to the negative and positive responses for low PFI levels were 35.9 and 16.1%, and, for high PFI levels, were 15.3 and 24.1%, among Chinese children and adolescents, respectively. Compared with the correlates at family and school levels, the correlates at individual levels had the largest PAR%. Conclusion: Individual-, family-, and school-multilevel factors had a significant cumulative association with either improving or worsening aspects of physical fitness. Individual level factors remain at the core of physical fitness improvement. Comprehensive policies and measures are urgently needed to enhance the physical fitness of Chinese children and adolescents through involving further individual and environmental factors.

Two-Year Change in Blood Pressure Status and Left Ventricular Mass Index in Chinese Children

Background: Elevated blood pressure (BP) is associated with target organ damage, such as left ventricular hypertrophy (LVH), in childhood. However, it is unclear if children who resolve elevated BP have reduced levels of left ventricular mass index (LVMI). This study aimed to examine the association between change in BP status over 2 years and LVMI among Chinese children.

Methods: Data were from 1,183 children aged 6–11 years at baseline in 2017 who were followed up in 2019 in the Huantai Childhood Cardiovascular Health Cohort Study. Change in BP status over 2 years from baseline to follow-up was categorized as: persistent normal BP, resolved elevated BP (elevated BP at baseline, normal BP at follow-up), incident elevated BP (normal BP at baseline, elevated BP at follow-up), and persistent elevated BP. Elevated BP status was defined according to national reference standards as systolic or diastolic BP levels ≥ sex-, age-, and height-specific 95th percentiles.

Results: LVMI levels were lowest in children with persistent normal BP (30.13 g/m^2.7), higher in those with incident elevated BP (31.27 g/m^2.7), and highest in those with persistent elevated BP (33.26 g/m^2.7). However, LVMI levels in those who had resolved elevated BP (30.67 g/m^2.7) were similar to those with persistent normal BP. In the fully adjusted model, compared with children with persistent normal BP, those with persistent elevated BP and incident elevated BP had higher LVMI at follow-up (ß = 3.131, p < 0.001; ß = 1.143, p = 0.041, respectively). In contrast, those who had resolved elevated BP did not have a significantly higher LVMI (ß = 0.545, p = 0.194) than those with persistent normal BP.

Conclusion: Developing or maintaining elevated BP over a 2-year period in childhood associated with higher levels of LVMI, but those able to resolve their elevated BP status over the same period had LVMI levels that were similar with those who had normal BP at both time points. Thus, it is important to identify children with elevated BP at early time and to take effective measures to lower their BP levels, thereby reducing high LVMI levels and related cardiovascular diseases in the future.

Association between Body Fat and Elevated Blood Pressure among Children and Adolescents Aged 7-17 Years: Using Dual-Energy X-ray Absorptiometry (DEXA) and Bioelectrical Impedance Analysis (BIA) from a Cross-Sectional Study in China

To investigate the associations between body fat percentage (BF%) with childhood blood pressure (BP) levels and elevated BP (EBP) risks, and further examine the validity of bioelectrical impedance analysis (BIA), we conducted a cross-sectional study of 1426 children and adolescents aged 7–17 years in Beijing, 2020. EBP, including elevated systolic BP (ESBP) and elevated diastolic BP (EDBP), was defined based on the age- and sex-specific 90th BP reference values of children and adolescents in China. BF% was measured by dual-energy X-ray absorptiometry (DEXA) and BIA devices, and was divided into four quartiles. Log-binomial models were applied to calculate odds ratios (ORs) and 95% confidence intervals (95%CI). Girls tended to have higher BF% levels than boys (p < 0.05). There was 41.0% of girls who developed EBP. High BF% was associated with increased BP levels with ORs of 0.364 (95%CI = 0.283–0.444) for SBP, 0.112 (95%CI = 0.059–0.165) for DBP, and 1.043 (95%CI = 1.027–1.059) for EBP, while the effects were more pronounced in girls and older-aged children. BIA devices agreed well with BF% assessment obtained by DEXA. High BF% might have negative effects on childhood BP. Convenient measurements of body fat might help to assess childhood obesity and potential risks of hypertension.

Association of personal fine particulate matter and its respiratory tract depositions with blood pressure in children: From two panel studies

Evidence is limited regarding the acute effects of personal fine particulate matter (PM_2.5) exposure and its respiratory tract depositions on the alteration of children's blood pressure (BP). We conducted 2 longitudinal panel studies in 2 cities to evaluate the relations of 72-h real-time personal PM_2.5 exposure and its depositions in 3 respiratory tract regions over different lag times with BP and the risk of prehypertension and hypertension among 286 children aged 4-12 years. We found the strongest effects of PM_2.5 exposure on increased BP and risk of prehypertension and hypertension at lag 2 day, in dose-response manner, even when PM_2.5 below Chinese Ambient Air Quality Standard (CAAQS) Grade II. Moreover, compared to PM_2.5, tracheobronchial and alveolar depositions displayed more evident effects on BP outcomes. Interestingly, all above relationships were stronger among children in Guangzhou with lower PM_2.5 and its deposited doses than those in Weinan. Additionally, boys and those with daily extra-school activity ≥ 1 h were more susceptible to PM_2.5-induced BP effects with significant interactions. Our results highlighted that short-term PM_2.5 exposure and its respiratory tract depositions were dose-responsive related to higher BP, prevalence of prehypertension and hypertension among children, even when PM_2.5 below CAAQS II.

Association between pubertal development and elevated blood pressure in children

Blood pressure (BP) increased with age and height development, but little was known about the effect of pubertal development on blood pressure in children. A cross‐sectional study was performed among 4146 children aged 7–12 years old in China. Pubertal development was assessed based on breast stages and testicular volume. The associations of pubertal development with BP levels and the rate of elevated blood pressure (EBP) were quantified using multiple linear and logistic regressions. We found that pubertal developmental level was positively correlated with BP, and children who experienced puberty onset and early pubertal timing had higher BP levels and prevalence of EBP. After adjusting for covariates, children experienced puberty onset had 3.84 and 2.24 mmHg increase in systolic blood pressure and diastolic blood pressure, and 70%, 53%, and 62% increased odds of EBP, ESBP, and EDBP, respectively, compared with those without puberty onset. Similar results were observed for children who had early pubertal timing. The change of BP in puberty is greater and the association between pubertal development and BP is stronger in girls than boys. These findings suggested that pubertal development could be an important independent factor and one critical period for the EBP progress. Monitoring and management of pubertal development are necessary particularly among girls.

Targeted gene panel sequencing for molecular diagnosis of congenital adrenal hyperplasia

CONTEXT

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive genetic diseases caused by genetic deficiency in nine genes encoding steroidogenesis enzymes and cofactors.

OBJECTIVE

To establish a targeted next-generation sequencing (NGS) assay for all nine CAH candidate genes.

METHODS

We developed a customized targeted NGS assay of CAH candidate genes (CYP21A2, CYP17A1, CYP11B1, StAR, CYP11A1, POR, HSD3B2, H6PD, CYP11B2) and apply this assay plus MLPA of CYP21A2 in a total of 469 patients with CAH like signs and symptoms.

RESULTS

We totally identified 125 variants with seven variant types in eight genes. Variant types included missense variant (46.8 %), splicing variant (21.5 %), small indel (12.5 %), large structure variation (11.8 %), nonsense variant (4.1 %), UTR variant (2.9 %), synonymous variant (0.3 %). Successful genotyping, defined as biallelic pathogenic or likely pathogenic variants, was achieved in 98.5 % (336/341) of cases, including biallelic variants in CYP21A2 (n = 254), CYP17A1 (n = 45), CYP11B1 (n = 23), StAR (n = 7), HSD3B2 (n = 4), POR (n = 1), CYP11A1 (n = 1) and CYP11B2 (n = 1) gene. Importantly, the assay found one patient with CYP11B1 deficiency, one patient with non-classic POR deficiency and two patients with non-classic CYP17A1 deficiency while clinically diagnosed differently.

CONCLUSIONS

Our NGS-based assay plus MLPA of CYP21A2 is a useful tool to genotype all subtypes of CAH. The test successfully achieved genotype in 98.5 % of patients with clinically determined CAH. It also efficiently facilitated the diagnosis of CAH in patients with rare subtypes as well as non-classic phenotypes.

Neutrophil to Lymphocyte Ratio Is Increased and Associated With Left Ventricular Diastolic Function in Newly Diagnosed Essential Hypertension Children

Aim: Hypertension is associated with cardiac structural and functional changes, including left ventricular hypertrophy (LVH) and LV systolic dysfunction diastolic dysfunction. Neutrophil-to-lymphocyte ratio (NLR) is a novel inflammatory biomarker associated with cardiovascular diseases. The current study aimed to evaluate NLR in children with newly diagnosed essential hypertension and its relationship between blood pressure and cardiac changes. Methods and Subjects: Sixty-five children with newly diagnosed essential hypertension and 54 healthy children were included. Clinical characteristics, blood cell counts, and biochemical parameters were collected. LVH was assessed by calculation of LV mass index (LVMI), and LV systolic function was evaluated by measuring LV ejection fraction and fractional shortening. LV diastolic function was primarily assessed with E/E' ratio by Doppler and echocardiography. Results: The hypertension children had significantly higher LVMI and E/E' ratio than the controls, whereas there was no difference in LV systolic function between the two groups. The NLR was significantly higher in the hypertension group than the control group. Moreover, NLR was positively correlated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) levels in the hypertension group. Additionally, a significantly positive correlation between NLR and E/E' ratio was found in the hypertension group. However, NLR was not related to LVH and LV systolic function indicators in hypertension children. Conclusion: NLR is elevated in hypertension children, and it is associated positively with office blood pressure levels. Moreover, NLR may help assess LV diastolic function in hypertension children.

Association Between Diet Quality and Cardiometabolic Risk Factor Clustering Stratified by Socioeconomic Status Among Chinese Children

BACKGROUND

Few studies have evaluated the long-term relationship between diet quality and cardiometabolic risk factor clustering among children. The moderating effect of socio-economic status (SES) is of interest.

OBJECTIVE

To investigate the association between diet quality with cardiometabolic risk among Chinese children and to explore the moderating effect of SES.

DESIGN

In this cohort study, 5 waves (1997-2009) of the China Health and Nutrition Survey were used. Diet quality was measured by a modified version of the Chinese Children Dietary Index (mCCDI) based on Dietary Guidelines for Chinese.

PARTICIPANTS

Children between the ages of 7 and 17 (n = 2903) who completed at least 2 surveys were included. Those who missed measures or had hypertension or diabetes at baseline were excluded.

MAIN OUTCOME MEASURES

The fasting blood samples were collected in 2009. Waist circumference (WC) and blood pressure (BP) were measured in each survey.

STATISTICAL ANALYSIS PERFORMED

A continuous cardiometabolic risk score (MetScore) was derived by a confirmatory factor analysis of 5 components: WC, BP, glucose, triglycerides, and high-density lipoprotein cholesterol. Considering the latency period of the effect of behaviors, the mCCDI was lagged by the period between surveys. Linear regression was used to analyze the association of mCCDI with MetScore and its components. Mixed effect linear regression and lagged mCCDI were used for WC and BP models.

RESULTS

Higher mCCDI was independently associated with a lower MetScore at follow-up (β: -.11; 95% CI: -.18 to -.04). Higher lagged mCCDI over time was associated with a lower WC z score overall (β: -.05; 95% CI: -.08 to -.01) and among children in the low SES group (β: -.09; 95% CI: -.14 to -.04) but not those in the high SES group. When examining the 15 mCDDI components separately, scores for 5 components: more grains, vegetables, soybeans and its products; less sugar-sweetened beverages; and more diet variety were significantly associated with a lower MetScore.

CONCLUSIONS

Among Chinese children, higher diet quality measured by mCCDI was independently associated with a lower MetScore at follow-up.

School-based surveillance on visit-to-visit blood pressure variability and high blood pressure in children and adolescents

BACKGROUND

The predictive importance of visit-to-visit blood pressure variability (VVV) for high blood pressure (HBP) in a pediatric population has been largely unsettled. We aimed to evaluate it based on Health Promotion Program for Children and Adolescents (HPPCA), a school-based surveillance conducted from 2012 to 2018 in Suzhou, China.

METHODS

A total of 330,618 participants had BP measurement in 2018 and ≥ 3 BP records during 2012-2017, were recruited from HPPCA. Absolute BP values (in mmHg) were converted into age-, sex- and height- normalized z-scores. VVV was expressed as standard deviation (SD), coefficient of variation (CV) or average real variability (ARV) of BP z-scores during 2012-2017. Logistic regression models were used to assess the associations between VVV and HBP in 2018.

RESULTS

In 2018, 42,554 (12.87%) subjects were defined as HBP. VVV, except for SBP-CV and DBP-CV, was significantly higher in the HBP group than normotensives group. After adjusting for covariates including mean BP values from 2012 to 2017, SBP-SD, SBP-ARV, DBP-SD and DBP-ARV, increased the risk of HBP by 5.70 [95% confidence interval (95% CI) 5.54-5.87], 4.10 (95% CI 4.01-4.20), 4.70 (95% CI 4.50-4.90) and 3.39 (95% CI 3.28-3.50) times, respectively. Notably, SBP-SD significantly improved risk discrimination of HBP based on other risk variables (c-statistics, net reclassification index and integrated discrimination improvement significantly increased).

CONCLUSIONS

Higher SD or ARV of BP, was independently related with higher probability of HBP in Chinese pediatric population. SBP-SD could be potentially helpful for detecting HBP. Future researches investigating the predictive value of VVV are warrant.

Associations of Plasma Copper, Magnesium, and Calcium Levels with Blood Pressure in Children: a Cross-sectional Study

Studies of the relationship of copper (Cu), magnesium (Mg), and calcium (Ca) levels with blood pressure in children are limited. This cross-sectional study included 443 children aged 6-9 years from Guangzhou, China. Plasma concentrations of Cu, Mg, and Ca were measured by inductively coupled plasma mass spectrometry. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured with an electronic sphygmomanometer. Elevated SBP and DBP were defined as the 90th percentile or greater (age and sex specific) of reference values for Chinese children. Abnormal blood pressure (ABP) was defined as an elevated SBP and/or DBP. The plasma Cu concentration was positively correlated with blood pressure, body mass index (BMI), and the C-reactive protein (CRP) level, whereas the plasma Mg and Ca concentrations were negatively correlated with SBP. A higher Cu concentration (T3 vs. T1) was associated with a higher risk of ABP (odds ratio (OR) 2.55, 95% confidence interval (CI) 1.20 to 5.40). In contrast, children in the top tertiles of Mg (OR 0.42, 95% CI 0.18 to 0.98) and Ca (OR 0.28, 95% CI 0.11 to 0.70) concentrations showed lower risks of ABP than those in the bottom tertiles. Path analysis showed that the CRP levels and BMI mediated the associations between the Cu concentration and ABP. We found that higher plasma Mg and Ca concentrations were negatively related to blood pressure in children aged 6-9 years. In contrast, a higher plasma Cu concentration was positively correlated with the risk of ABP, and the association was mediated by CRP and BMI.

Prevalence trends of hypertension among 9-17 aged children and adolescents in Yunnan, 2017-2019: a serial cross-sectional surveillance survey

BACKGROUND

We aim to describe the prevalence and trends of hypertension among 9-17 school-aged students from 2017 to 2019 in Yunnan, China.

METHODS

We conducted a cross-sectional study by using data from the Students' Health Surveillance Surveys of 2017, 2018 and 2019 in Yunnan. The Students' Health Surveillance Surveys in Yunnan collected date on physical fitness and health status of students in Yunnan through multistage-stratified sampling in 3 prefectures. In each prefecture, the study population were classified by gender and region (urban or rural), and each group had an equal size. Diagnosing criteria of hypertension was set with reference to Chinese age-specific and height-specific blood pressure (BP), to identify the abnormal status of boys and girls separately. ANOVA test was adopted to measure the differences in the mean BP stratified by gender, age, prefecture and area, and Chi-square test was used to compare the percentages of hypertension in different areas. For comparability, the age-standard and gender-standard population prevalence was calculated by directly using China Census in 2010 as a standard population. Totally 24,890 participants aged 9-17 years were included in this study.

RESULTS

From 2017 to 2019, there were 24,872 students completed physical examinations and included in the analysis, of which 3288 were diagnosed with hypertension. The total prevalence of hypertension was 13.72, 12.49 and 13.45% among 9-17 years school-aged population in Yunnan, respectively. The total age-standardized hypertension prevalence trended to decrease from 13.82 to 13.48%. For urban population, the age-standardized hypertension prevalence decreased slightly from 11.24 to 10.13%. While, for rural population, it increased from 17.58 to 19.16%. The average annual growth rate in rural population was 0.53%.

CONCLUSIONS

From 2017to 2019, there was a significant and continuous increase in the prevalence of hypertension in 9-17 years school-aged population in Yunnan. Hypertension is epidemic among children and adolescents in Yunnan. We should take effective and comprehensive intervention measures to reduce its prevalence among school-aged children.

Sex-Specific Differences in Related Indicators of Blood Pressure in School-Age Children With Overweight and Obesity: A Cross-Sectional Study

Objective: The objective of this study is to further explore the difference between elevated blood pressure (EBP), elevated pulse pressure (EPP), and elevated mean arterial pressure (EMAP) and obesity in Chinese school-age children by sex. Methods: We performed a cross-sectional study of 935 children between 7 and 12 years old. Overweight and obesity were defined by body mass index and body composition. The multivariate logistic regression and the adjusted population attributable risk were used to assess the effects of obesity on pre-EBP/EBP, EPP, and EMAP. The interactions were used to identify the modification of obese on the relationship between related indicators of blood pressure and height or age. Results: The average age of the children included in the study was 10. Boys with overweight and obesity had higher pre-EBP/EBP, EPP, and EMAP (p < 0.05). The multivariate logistic regression analysis showed that overweight and obesity had a greater impact on BP and MAP than PP, especially in boys [odds ratio (OR) > 1]. Pre-EBP/EBP in 79% of boys and 76% of girls could be attributable to the visceral fat level. The interaction between BP, PP, MAP, and height or age was modestly increased in children with overweight and obesity, especially in boys. Conclusions: Independent of age and height, obesity not only increases blood pressure, it also increases mean arterial pressure and pulse pressure, and this effect is more pronounced in boys.

Lifestyle Clusters and Cardiometabolic Risks in Adolescents: A Chinese School-Based Study Using a Latent Class Analysis Approach

Background: Unhealthy dietary and lifestyle behaviors are associated with a higher prevalence of non-communicable chronic diseases and higher mortality in adults. However, there remains some uncertainty about the magnitude of the associations between lifestyle behaviors and cardiovascular factors in adolescents. Methods: We conducted a school-based cross-sectional study of 895 Chinese adolescents aged 15-19 years. They participated in a questionnaire survey, physical examination, and blood sample collection. Latent class analysis (LCA) was used to identify heterogeneous subgroups of lifestyle behaviors. A set of 12 latent class indicators, which reflected lifestyle behaviors including dietary habits, physical activity, sleep duration, screen time, and pressure perception, were included in the analysis. Logistic regression analysis was performed to determine whether the derived classes were related to a cardiometabolic risk. Results: In total, 13.7 and 5.6% of the participants were overweight and obese, respectively, and 8.4 and 14.1% reported having pre-hypertension and hypertension, respectively. A two-class model provided the best fit with a healthy lifestyle pattern (65.8%) and a sub-healthy lifestyle pattern (34.2%). There were more female participants with a healthy lifestyle (56.2 vs. 43.8%), whereas there were more males with a sub-healthy lifestyle (45.4 vs. 54.6%), (all P = 0.002). Increased risk of cardiometabolic abnormality (BMI categories, blood pressure and lipids) was not significant across lifestyle patterns, except for waist circumference (70.5 vs 69.1 cm, P = 0.044). There was no significant difference in physical activity and intake of fruit and vegetable between the two patterns. Conclusion: Primary prevention based on lifestyle modification should target patterns of behaviors at high risk in adolescents. Due to the complex effect of lifestyle clusters on cardiometabolic risks, well-designed and prospective studies in adolescents are needed in the future.

Sex differences in changes in BMI and blood pressure in Chinese school-aged children during the COVID-19 quarantine

There may be sex differences in BMI and blood pressure levels in school-age children, especially in the face of lifestyle changes. This study aimed to explore sex differences in changes in BMI and blood pressure in Chinese school-aged children during the COVID-19 quarantine. The cohort study of 445 school-aged children examined the change of BMI and blood pressure during the five-month quarantine. Multivariable Cox regression models were created to identify potential predictors of overweight, obesity, and elevated blood pressure (EBP). During the COVID-19 quarantine, the proportion of boys with overweight and obesity increased (P = 0.036), and the proportion of both boys and girls with Pre-EBP and EBP increased (P = 0.004 in boys; P < 0.001 in girls). The multivariate Cox regression analysis demonstrated that the setting, eating chili, parents' perception of their child's size and family doting were associated with overweight, obesity, and EBP. The study showed that BMI was more likely to increase in boys, and blood pressure increased in both boys and girls during the COVID-19 quarantine.

Does underweight amplify the relationship between short-term particulate matter exposure and blood pressure in children and adolescents: a large cross-sectional study in a metropolis of China

Overweight/obesity modified the effects of ambient particulate matter (PM) exposure on blood pressure (BP). This study aims to assess whether interaction of underweight and short-term PM exposure on BP exists in Chinese children. A cross-sectional analysis including 144,513 children aged 6 to 17 years in 2016 Health Promotion Program for Children and Adolescents of Suzhou, China, was performed. Daily concentrations of inhalable PM (PM₁₀) and fine PM (PM_2.5) were extracted from air monitoring stations close to students' schools. We applied generalized linear mixed-effects models to estimate the interactions. Estimated changes (95% confidence intervals (CIs)) of systolic BP (SBP), diastolic BP (DBP), and odds ratios (ORs) (95% CIs) for prevalence of HBP were calculated. Significant interactions between PM and underweight on BP and prevalence of high BP (HBP) were observed. For example, at lag 6, the ORs (95% CIs) for HBP by each 10 μg/m³ changes of PM_2.5 were 1.066 (1.039, 1.093) and 1.036 (1.028, 1.043) among underweight and normal weight subjects, respectively; these values for PM₁₀ were 1.048 (1.031, 1.065) and 1.025 (1.021, 1.030). At lag 5, the increases of SBP for PM_2.5 were 0.32 (95% CI 0.22, 0.43) mmHg and 0.23 (95% CI 0.29, 0.26) mmHg, while changes of DBP were 0.27 (95% CI 0.18, 0.35) mmHg and 0.19 (95% CI 0.16, 0.21) mmHg among underweight and normal weight subjects, respectively. Stratified analyses demonstrated that these interactions were only obtained in males. Effects of short-term PM exposure on BP and prevalence of HBP are enhanced in underweight children and adolescents.

Risk Factors for Orthostatic Hypertension in Children

OBJECTIVE

To investigate the risk factors for orthostatic hypertension in children.

STUDY DESIGN

Eighty children with orthostatic hypertension were enrolled in the group with orthostatic hypertension, and 51 healthy children served as the control group. Demographic characteristics, clinical history, daily water intake, nightly sleep duration, the results of the standing test, and complete blood count were recorded and compared between the 2 groups. The risk factors for pediatric orthostatic hypertension were determined by logistic regression analysis.

RESULTS

Body mass index and red blood cell distribution width were higher in the group with orthostatic hypertension than in healthy children, whereas daily water intake and sleep duration were lower. Logistic regression analyses showed that, if a child suffered from overweight, suffered from obesity, had a daily water intake of less than 800 mL, or had a red blood cell distribution width that was increased by 1%, the risk of orthostatic hypertension would be increased by 6.069 times (95% CI, 1.375-26.783; P < .05), 7.482 times (95% CI, 1.835-30.515; P < .01), 4.027 times (95% CI, 1.443-11.241; P < .01), or 4.008 times (95% CI, 1.698-9.461; P < .01), respectively. However, if the sleep duration was increased by 1 hour, the risk of developing orthostatic hypertension would be decreased by 74.3% (95% CI, 54.6%-85.4%, P < .01).

CONCLUSIONS

Increased body mass index, inadequate water intake and sleep duration, and elevated red blood cell distribution width were identified as risk factors for pediatric orthostatic hypertension.