Objective: To explore differences in the detection rate of elevated blood pressure (BP) in children aged 6-8 years old, and to verify the apparent existence of white-coat hypertension (BP) in children. Methods: Based on census data(PROC), and three subsequent BP readings were taken during follow-ups which were carried out from October 2018 to June 2019. A total of 1 785 children were included in the present study. Using updating blood pressure reference for Chinese children aged 3-17 years, compared the BP detection rate at baseline, at the first follow-up, and the average value of the last two BP readings. Fluctuations in the detection rate of elevated BP in children at different time-points were analyzed. Results: The detection rates of the three elevated BP measurements of 6-8-year-old children were 57.65%, 25.88% and 15.46%, respectively, and the detection rate was higher among boys than girls. The detection rate of baseline BP was higher than that of the first follow-up BP measurements and the average of the last two BP measurements(P<0.01). Given the agreement in the diagnosis of high SBP, high DBP, high BP at baseline, and the average of the last two follow-up BP measurements, elevated BP at baseline was the lowest among the three groups and SBP was higher than DBP. Conclusion Blood Pressure fluctuations might be caused by transient tension that was experienced during the baseline BP measurement and during the first of the three follow-ups. Therefore, the average value of last two BP measurements may better reflect the real BP level in children.

Objective: To examine the association between the visceral adiposity index (VAI) and nonalcoholic fatty liver disease (NAFLD) in the pediatric population in order to improve risk stratification and prevention systems for chronic liver disease. Methods: A total of 510 overweight/obese children aged 6-8 years old were enrolled from the child cohort which was designed to study puberty, obesity, and cardiovascular risk (PROC), and complete data from liver ultrasounds and the VAI were obtained. Used Spearman s rank correlation coefficient, Chi-square tests, and Logistic regression analyses to explore the association between the VAI and NAFLD. Results: The detection rates of NAFLD for boys and girls were 25.9% and 11.1%, respectively. VAI for normal group and the NAFLD group were 0.43(0.31, 0.61) and 0.61(0.44, 0.87) in boys, and 0.74(0.56, 1.07) and 1.08(0.67, 1.51) in girls, respectively. Spearman s correlation coefficient analysis showed that triglycerides(TG), VAI, and the third quintile VAI group were positively correlated with NAFLD in both boys and girls(r=0.19,0.26,0.29;0.16,0.16,1.18,P<0.05), and high-density lipoprotein-cholesterol (HDL-C) was negatively correlated with NAFLD in boys (r=-0.21, P<0.05). With advancing tertiles of VAI, the increasing trend in the NAFLD detection rate was statistically significant in boys and girls(Chi-square for trend were 21.77,7.66, P<0.01). The results of univariate and multivariable Logistic regression showed that, by taking the first tertile of VAI as a reference, the risk of NAFLD among boys was higher in the second tertile (cOR=2.59, 95%CI=1.15-5.86; aOR=2.33, 95%CI=1.01-5.36) and in the third tertile(cOR=5.73, 95%CI=2.62-12.53; aOR=4.87, 95%CI=2.15-11.03), where as the risk among girls was higher in the third tertile(cOR=4.43, 95%CI=1.40-14.00). Conclusion VAI is positively correlated with pediatric NAFLD. Higher tertiles of VAI were associated with an increased risk of NAFLD in overweight and obese children, which indicates that VAI can be used as an early predictor of NAFLD.

Objective: To understand the epidemiological characteristic of the prevalence of aasthma in children in China, and to provide clues for the prevention and treatment of asthma in China. Methods: A systematical literature retrieval on children asthma prevalence from CNKI, WanFang Data, VIP and PubMed databases was performed. Random effects model was used to calculate the combined prevalence of asthma and its 95% confidence interval (CI) with Stata 16.0 software, the subgroup analysis was conducted according to sex, age and region. Results: A total of 26 studies were included, including 213 729 children, 112 169 boys and 101 560 girls. Meta-analysis showed that the combined prevalence of asthma in children aged 14 and under in China was 3.3%(95%CI=2.7%-4.0%). The subgroup analysis showed that the prevalence of asthma in boys was higher than that in girls(Q=11.42, P=0.01). The prevalence of asthma in preschool children aged 4-6 was higher than that in infants aged 0-3 and school children aged 7-14(Q=8.03, P=0.02). And there was no significant discrepancy of the asthma prevalence among children between the north and south(Q=0.72, P>0.05). Conclusion The prevalence of childhood asthma in China presented an increasing trend. Our findings underscore more efforts to control and prevent asthma among children.

Objective:The study intends to identify gap in HIV/AIDS awareness dissemination between the official channel delivery and the needs of adolescents.Methods:We crawled all the HIV/AIDS queries from “Baidu zhidao” till June 11st, 2018. “Baidu zhidao” inquiry and information form official public service announcement (abbreviated for “official delivery” hereafter) were the data source for comparative analysis. We categorized the text data into four kinds, “prevention”, “testing and treatment”, “symptoms and infection” and “legalization and policies” according to official categorization. Word segmentation was used for text mining and word frequency statistics, as well word cloud was used for word frequency visualization (all based on a comparison after removing the useless words).Results:Of the official delivery, the proportion of prevention category accounted for 32.3% ( n=162) (ranks 1 st), and the proportion of legalization and policies category was 14.1% ( n=71). While among the “Baidu zhidao” inquiry information, the proportion of testing and treatment category accounted for 51.7% ( n=51 264), and the proportion of prevention category accounted for 11.4% ( n=11 272). The frequencies of same terms/ repeated terms of two channels accounted for 60% (59.3%-63.9%) of each category among the official delivery, of which, the proportion of interest terms comparatively less and more diverse in “Baidu zhidao” inquiries. The proportion of the terms frequency of each category was about 45% in “prevention, testing and treatment”, 34.3% ( n=14 781) in “symptoms and infection” and 17.0% ( n=5 744) in “legalization and policies”, respectively. Conclusion:A big gap was identified between the available official source and inquiries’ term, especially word frequency discrepancy between “legalization and policies” and “prevention” categories. It underscore the necessity for the official channel to address the needs and interests of adolescents in the future.

Objective:The study intends to identify gap in HIV/AIDS awareness dissemination between the official channel delivery and the needs of adolescents.Methods:We crawled all the HIV/AIDS queries from “Baidu zhidao” till June 11st, 2018. “Baidu zhidao” inquiry and information form official public service announcement (abbreviated for “official delivery” hereafter) were the data source for comparative analysis. We categorized the text data into four kinds, “prevention”, “testing and treatment”, “symptoms and infection” and “legalization and policies” according to official categorization. Word segmentation was used for text mining and word frequency statistics, as well word cloud was used for word frequency visualization (all based on a comparison after removing the useless words).Results:Of the official delivery, the proportion of prevention category accounted for 32.3% ( n=162) (ranks 1 st), and the proportion of legalization and policies category was 14.1% ( n=71). While among the “Baidu zhidao” inquiry information, the proportion of testing and treatment category accounted for 51.7% ( n=51 264), and the proportion of prevention category accounted for 11.4% ( n=11 272). The frequencies of same terms/ repeated terms of two channels accounted for 60% (59.3%-63.9%) of each category among the official delivery, of which, the proportion of interest terms comparatively less and more diverse in “Baidu zhidao” inquiries. The proportion of the terms frequency of each category was about 45% in “prevention, testing and treatment”, 34.3% ( n=14 781) in “symptoms and infection” and 17.0% ( n=5 744) in “legalization and policies”, respectively. Conclusion:A big gap was identified between the available official source and inquiries’ term, especially word frequency discrepancy between “legalization and policies” and “prevention” categories. It underscore the necessity for the official channel to address the needs and interests of adolescents in the future.

Abstract The prevalence of cardiometabolic risk factors at early lifecycle stages is higher than ever before, early identification and stratified intervention are critical to slowing down disease progression and reducing cardiovascular disease risk burden in adulthood. The implementation of stratified interventions to address the co-prevalence of cardiometabolic risk factors can reduce health expenditure and increase social capital. Guided by the policies and characteristics inherent to the growth and development of Chinese children, and nurtured and inspired by prestigious child cohorts around the world, we aim to carry out a precisely measured child cohort study that uses rigorous indicators to assess child health. We wish to produce detailed evidence that can identify cardiometabolic risk factors during childhood, so as to develop early warning and informed stratified intervention strategies, which can thereby reduce the burden of cardiovascular disease in China from childhood to adulthood and improve quality of life.

Objective: The study aimed to explore sex differences in the growth and physical development of Beijing school-aged children and adolescents. Methods: Data obtained from regular health examinations of 94 122 school-aged children and adolescents aged 6-18 years old were collected from primary and high schools in Shunyi District from 2009 to 2018, and a longitudinal dataset was compiled with complete anthropometric parameters including height, weight, and BMI levels after linkage of individuallevel information. The age-specific growth rate was calculated and a linear mixed-effects model was used to identify sex differences according to chronological or relative age to peak height velocity (PHA). Results: Height, weight, and BMI levels increased with age in both boys and girls. Girls were taller than boys in the 10-11 year-old age group, catch-up growth in height was observed in boys at age 12, whose height surpassed that of girls thereafter. Boys had a higher weight and BMI than girls in all age groups (P<0.01). Sex differences were found in the growth rates of height, weight, and BMI levels(t=-67.56，-47.46，3.22，P<0.01), which was demonstrated by the interaction effect of sex and age in the linear mixed-effects model. The PHA in boys was 12 years old, which was two years later than the PHA in girls. Boys reached peak weight velocity at 12 years old, lagging one year behind girls who reached their peak at 11 years old. The curves of the BMI growth rate with age showed double peaks in boys and the first peak appeared at 10 years, which was one year earlier than girls. The change in weight was highly synchronized in time with the increase in height, after adjusting for the growth rate of weight by PHA. Weight velocity increased with age before the onset of puberty until PHA, and then it declined; boys presented with obvious fat accumulation before the onset of puberty. Conclusion Sex differences in the growth and physical development of school-aged children and adolescents were persistent and apparent, and the change in weight was highly synchronized in time with the increase in height.

Objective: To explore sex differences between weight and systolic blood pressure (SBP) changes among school-age children and adolescents in Beijing, and to provide a basis for priority intervention to control the rapid growth of body weight and blood pressure. Methods: Anthropometric measurement data of 70 288 children and adolescents from primary and high schools in Shunyi District were collected from 2009 to 2018, and a longitudinal dataset with complete data related to weight and BP after individual data linkage was compiled. The age-specific weight and SBP growth rates were calculated, and a linear mixed-effects model was used to identify sex differences in chronological growth rates. Results: Weight and SBP increased with age in both boys and girls, and the mean weight and SBP were higher in boys than in girls across all age groups. The result of the linear mixed-effects model indicated apparent sex differences in weight and SBP growth rates, with an age and sex interaction term(β=-0.35, -0.40, P<0.01). The age at peak weight velocity (PWA) was 12 years old and the age at peak SBP velocity was 13 years old in boys, which occurred one and three years later than for girls, respectively. In addition, the peak weight and SBP velocity were higher in boys than in girls. The curves of the SBP growth rate adjusted for the PWA, showed that the peak SBP velocity occurred two years before PWA and the second peak SBP velocity occurred at the PWA, which indicated "double peaks" in both boys and girls. The SBP growth rate was always higher in boys than in girls, and the rates declined after PWA. Conclusion Sex differences in weight and SBP growth rates were persistent and obvious in school-age children and adolescents in Beijing and the change in SBP was highly time synchronized with the increase in weight.

Objective: To identify the association of carotid intima-media thickness (cIMT) and visceral fat area (VFA) to inform prevention of cardiovascular disease in later life. Methods: All the grade one students of six non-boarding primary schools in Shunyi District, Beijing were enrolled, based on population-based survey design, to establish the child cohort on sensitization, puberty, obesity and cardiovascular risk (PROC). Socio-demographic information survey and anthropometric measure, blood and urine test were carried out. Robust linear regression was used to determine the relationship between cIMT and other factors. Results: Among 1 711 participants, a significant difference were observed between normal, overweight and obesity children on cIMT [(0.35±0.02)(0.36±0.02)(0.37±0.03)mm] (F=41.4, P<0.01) and VFA [16.2(13.6-19.3), 22.7(18.6-27.3), 51.5(33.9-73.0)cm2] (χ2=854.5, P<0.01). After adjusting age and sex, univariate robust linear regression showed that cIMT was associated with height, SBP, DBP, HDL-C, VFA (P<0.05) and TG (P=0.055). Multivariable robust linear regression indicated that in total and boys only included models, cIMT was associated with VFA and SBP(β=0.000 2, 0.000 2, 0.000 2, 0.000 2, P<0.05); while in girls only included model cIMT was associated with VFA and TG (β=0.000 2, 0.006 2, P<0.05). Conclusion VFA is stable to predict the increase of cIMT in children. We can use VFA to simplify the classification management of children and inform targeted early prevention of cardiovascular disease in adulthood.

Objective:To understand the prevalence of asthma and its variation over time in children aged 0-14 years in China.Methods:The studies on the prevalence of asthma in children in China were systematically retrieved from China National Knowledge Infrastructure (CNKI), WanFang Data, China Science and Technology Journal Database (VIP) and PubMed databases. The search time was up to June 2019, and the study site was located in the asthma surveillance cities. Random effect model was used to calculate the combined prevalence of asthma and its 95% confidence interval ( CI). The subgroup analysis was conducted by period, sex and region. All analyses were performed by using Stata 15.1 and R Studio software. Results:Among 2 624 articles, 67 met the eligibility criteria, and the survey time was from 1989 to 2015. A total of 1 661 076 children were involved and 40 737 asthma cases were confirmed from 26 provinces, municipalities and autonomous regions. The prevalence of asthma varied greatly among different studies, ranging from 0.5% to 9.82%. Meta-analysis showed that the combined prevalence of asthma in Chinese children aged 0-14 was 2.6% (95% CI: 2.1%-3.1%), about 3.2% (95% CI: 2.6%-3.8%) for boys and 1.9% (95% CI: 1.6%-2.3%) for girls. The subgroup analysis showed a significant variation of the prevalence over different years, genders and regions ( P<0.05). The prevalence of asthma in boys was consistently higher than that of girls. The overall prevalence of asthma showed an upward trend. Before 2010, the prevalence of asthma in the eastern region was higher than that in the central and western regions. The prevalence of asthma across regions showed a significant change and the prevalence of asthma in the central region was significantly higher than that in the eastern and western regions from 2010 to 2015 ( P<0.05). Conclusion:The asthma prevalence of children aged 0-14 in China is generally increasing, and the prevalence rate of boys is higher than that of girls. The prevalence rate in the central region is significantly higher than that in the eastern region from 2010 to 2015, suggesting that those regions should strengthen the early prevention and intervention of asthma and implement a sex-specific information dissemination strategy.