Identifying reference values for serum lipids in Chinese children and adolescents aged 6-17 years old: A national multicenter study.

BACKGROUND: Current reference values for pediatric dyslipidemia used in China were not developed based on local population studies and did not consider age and sex differences. OBJECTIVE: In this study, we aimed to determine suitable reference values for total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), and non-high-density lipoprotein cholesterol (nonHDL-C) for Chinese children and adolescents using a national multicenter school-based study. METHODS: A total of 15,830 students aged 6-17 years were recruited from seven provinces of China. Age- and sex-specific percentile values for each lipid indicator were derived based on levels measured in the fasting state, and percentile curves of each indicator were plotted using the LMS method. RESULTS: Serum lipid levels varied considerably with age in both sexes. Among boys, the cut-off value for high TC, nonHDL-C, LDL-C, and TG, based on the value of the 95th percentiles, ranged from 4.58 to 5.39, 3.34 to 3.99, 2.69 to 3.31, and 1.22 to 1.83 mmol/L, respectively; among girls, the cut-off value for high TC, nonHDL-C, LDL-C, and TC ranged from 5.01 to 5.39, 3.66 to 3.97, 2.97 to 3.32, and 1.41 to 1.93 mmol/L, respectively. The cut-point for low HDL-C ranged from 0.84 to 1.08 mmol/L in boys and from 0.89 to 1.04 mmol/L in girls. CONCLUSION: These findings may help to determine age- and sex-specific reference values for serum lipids among Chinese children and adolescents and provide valuable guidance for screening of dyslipidemia.

Long-term exposure to ambient air pollution and metabolic syndrome in children and adolescents: A national cross-sectional study in China.

BACKGROUND: The prevalence of metabolic syndrome (MetS) rapidly increased over the past decades. However, little evidence exists about the effects of long-term exposure to ambient air pollution on MetS in children and adolescents. OBJECTIVE: This study aims to assess the association between long-term ambient air pollution and the prevalence of MetS in a large population of Chinese children and adolescents. METHODS: In 2013, a total of 9,897 children and adolescents aged 10 to 18 years were recruited from seven provinces/municipalities in China. MetS was defined based on the recommendation by the International Diabetes Federation (IDF). Satellite based spatio-temporal models were used to estimate exposure to ambient air pollution (including particles with diameters ≤1.0 µm (PM1), ≤2.5 µm (PM2.5), and ≤10 µm (PM10), and nitrogen dioxide (NO2)). Individual exposure was calculated according to 94 schools addresses. After adjustment for a range of covariates, generalized linear mixed-effects models were utilized to evaluate the associations between air pollutants and the prevalence of MetS and its components. In addition, several stratified analyses were examined according to sex, weight status, outdoor physical activity time, and sugar-sweetened beverages (SSBs) intake. RESULTS: The prevalence of MetS was 2.8%. The odds ratio of MetS associated with a 10 µg/m3 increase in PM1, PM2.5, PM10 and NO2 was 1.20 (95%CI: 0.99, 1.46), 1.31 (95%CI: 1.05, 1.64), 1.32 (95%CI: 1.08, 1.62), and 1.33 (95%CI: 1.03, 1.72), respectively. Regarding the MetS components, we observed associations between all pollutants and abdominal obesity. In addition, long-term PM1 and NO2 exposures were associated with the prevalence of elevated fasting blood glucose. Stratified analyses detected that the associations between air pollutants and the prevalence of MetS were stronger in boys (Pinteraction < 0.05). CONCLUSIONS: We found that long-term exposure to PM2.5, PM10, and NO2 were positively associated with the prevalence of MetS in children and adolescents. Our findings may have certain public health implications for some comprehensive strategy of environment improvement and lifestyles changes in order to reduce the burden of non-communicable disease.

Greenness surrounding schools and adiposity in children and adolescents: Findings from a national population-based study in China.

BACKGROUND: Previous studies have indicated that exposure to green space may benefit human health. However, the available evidence concerning the effects of greenness, especially school-based greenness, on pediatric obesity is scarce. OBJECTIVE: To explore the association between school-based greenness and adiposity in children and adolescents in China. METHOD: We conducted a nationwide cross-sectional study of 56,620 children and adolescents (aged 6-18 years) in seven provinces/municipalities across China. School-based greenness was assessed using satellite-derived Normalized Difference Vegetation Index (NDVI) and Soil Adjusted Vegetation Index (SAVI) within 100-, 500-, and 1000-m circular buffers around each school's address. Generalized linear mixed regression models were used to estimate associations of greenness with BMI z-scores (zBMI), waist circumference, and prevalent overweight/obesity. We also explored the potential mediating role of ambient air pollution and physical activity in the greenness-adiposity associations. RESULT: In the adjusted model, an IQR increase in NDVI-1000m was associated with lower zBMI (ß: -0.11, 95% confidence interval[CI]: -0.13,-0.09) and waist circumference (ß: -0.64, 95%CI: -0.78,-0.50). Consistently, an IQR increase in NDVI-100m, NDVI-500m, NDVI-1000m was associated with 7-20% lower odds of overweight/obesity in the adjusted models. Air pollutants mediated 6.5-29.1% of the association between greenness and zBMI. No significant mediation effect was observed for physical activity. CONCLUSION: Higher school-based greenness levels were associated with lower zBMI, waist circumference, and lower odds of overweight and obesity in children and adolescents. Ambient air pollutants may partially mediate the greenness-adiposity associations.

Analysis on the Implementation of Comprehensive School Health Evaluation in Liaoning Province / 中国学校卫生

Objective@#To understand the Implementation of Comprehensive Evaluation of School Health (GB/T 18205-2012) and associated factors, so as to provide rationalization proposals for future revision of standards.@*Methods@#A questionnaire survey was conducted on 436 schools, 56 health supervision agencies and 55 disease control agencies in Liaoning Province, and the main contents include the investigation of awareness rate, training, application, rationality and application of evaluation items and indicators.@*Results@#Totally 44 supervision agencies and 29 CDCs had independent school health departments, with significant differences in faculty equipment ( t =8.53， P <0.05). The standard was trained in 100% of municipal supervision agencies, 22.50% of district and county level, 46.15% of municipal CDC ,50.00% of district county CDC; 61.54% of municipal and 45.00% of district and county supervision agencies conducted evaluations in accordance with this standard, 53.85% of the municipal CDC, 60.00% of county CDC jointly completed the standard; 30.77% of municipal and 52.50% of district and county supervisory bodies informed the educational administration of the results of the comprehensive evaluation.@*Conclusion@#The establishment of school health professional departments and the training of management objects affect the implementation of comprehensive evaluation of school health, so it is necessary to combine the actual work to modify some of the important indicators, and strengthen the application of comprehensive evaluation results.

Health supervision of school based myopia prevention and control / 中国学校卫生

Objective@#To explore the associated factors in the implementation of the "random" sampling inspection of the lighting institutions in kindergartens, outofschool training institutions and primary and secondary schools in 2019 (Supervision Letter [2019] No. 314 of National Health Office) (hereinafter referred to as the "Plan"), and to provide reference for better implementation of the Plan.@*Methods@#A survey of schoolbased myopia prevention and control was conducted in 23 provincial, municipal and countylevel health supervision institutions in China. The main contents of the survey focused on the introduction, implementation and implementation of the program.@*Results@#The implementation of the "plan" was significantly associated with the specific work organized and coordinated by the health administrative department, clear responsibility of various departments, and collaboration with educational institutions[OR(95%CI)=1.57(1.05-2.36), 0.05(0.03-0.10), 0.31(0.19-0.52), 0.03(0.01-0.09), 0.12(0.04-0.37), P<0.05]. It was also associated with independent school health supervision department, one and two fulltime school health supervision staff equipment, onsite quick inspection of health supervision institutions, school selfexamination[OR=1.87(1.33-2.62), 0.62(0.40-0.97), 2.37(1.82-3.09), 1.62(1.09-2.40), P<0.05].@*Conclusion@#The program needs to be implemented through multiple departments and is associated with multiple factors. It is of great importance to strengthen multisector collaboration and clarify the responsibility of various departments for the health supervision of schoolbased myopia prevention and control.

The relationship between long-term exposure to PM2.5 and fasting plasma glucose levels in Chinese children and adolescents aged 6-17 years: A national cross-sectional study.

BACKGROUND: Previous studies investigating the association between PM2.5 exposure and fasting plasma glucose levels (FPGLs) are mostly limited to short- and mid-term PM2.5 exposure and lack adjustments for key confounders in adult research. OBJECTIVES: Exploring the relationship between seven years long-term PM2.5 exposure and FPGLs in Chinese children and adolescents aged 6-17 years. METHODS: Between September 2013 and December 2013, 16,489 participants aged 6-17 years were recruited using a four-staged, stratified, cluster sampling strategy from 7 provinces, autonomous regions and municipalities of mainland China. A generalized linear mixed model (GLMM) was used to estimate the relationship between annual PM2.5 exposure (2007-2013) and FPGLs stratified by sex and one-year age increments. Sociodemographic characteristics, living with both parents, early-life factors, behaviours, and infection symptoms were gradually adjusted from the crude model to regression model 6, and BMI was adjusted for in model 7. RESULTS: The annual concentration of PM2.5 was 56.23 (±12.99) µg/m3. The mean FPGLs in the 8551 boys (4.75 mmol/L ± 0.52) was significantly higher than that in the 8194 girls (4.63 mmol/L ± 0.48) (P < 0.0001). In model 6, for every 10 µg/m3 increase in PM2.5 exposure, the FPGLs in boys and girls increased by 0.048 (95% CIs 0.031 to 0.065) mmol/L (P < 0.0001) and 0.054 (95% CIs 0.039 to 0.069) mmol/L (P < 0.0001), respectively. The FPGLs were significantly positively associated with long-term PM2.5 exposure at the ages of 12, 15 and 16 years in both the boys and girls and exhibited age differences in model 7. The prevalence of impaired fasting plasma glucose (IFP) and diabetes decreased by 0.8% when the exposure concentration of PM2.5 was reduced by 10 µg/m3 in model 6, which assessed the negative effects of PM2.5 exposure and revealed that 1,298,920 children and adolescents could have been protected from IFP and diabetes in 2013 in China. CONCLUSIONS: Long-term PM2.5 exposure may be an independent risk factor of elevated FPGLs. The adverse effect of PM2.5 exposure on FPGLs in children and adolescents could appear after 10 years of cumulative exposure. The precise intervention time was revealed as approximately 12 and 11 years in boys and girls, respectively. There are great public health implications associated with early prevention strategies for the eradication of the negative effects of long-term exposure to PM2.5 on FPGLs.

The predictive value of anthropometric indices for cardiometabolic risk factors in Chinese children and adolescents: A national multicenter school-based study.

OBJECTIVES: This study aimed to assess the accuracy of body mass index (BMI) percentile, waist circumference (WC) percentile, waist-height ratio, and waist-hip ratio for identifying cardiometabolic risk factors in Chinese children and adolescents stratified by sex and BMI categories. METHODS: We measured anthropometric indices, fasting plasma glucose, lipid profile and blood pressure for 15698 participants aged 6-17 in a national survey between September and December 2013. The predictive accuracy of anthropometric indices for cardiometabolic risk factors was examined using receiver operating characteristic (ROC) analyses. The DeLong test and Z test were used for the comparisons of areas under ROC curves (AUCs). RESULTS: The prevalence of impaired fasting glucose, dyslipidemia, hypertension and cluster of risk factors were 2.9%, 27.3%, 10.5% and 5.7% respectively. The four anthropometric indices showed poor to fair discriminatory ability for cardiometabolic risk factors with the AUCs ranging from 0.53-0.72. Each index performed significantly better AUCs for dyslipidemia (0.59-0.63 vs. 0.56-0.59), hypertension (0.62-0.70 vs. 0.55-0.65) and clustered risk factors (0.70-0.73 vs. 0.60-0.64) in boys than that in girls. BMI percentile performed the best accuracy for hypertension in both sexes; WC percentile had the highest AUC for dyslipidemia and BMI percentile and waist-height ratio performed similarly the best AUCs for clustered risk factors in boys while BMI percentile, WC percentile and waist-height ratio performed similar and better AUCs for dyslipidemia and clustered risk factors in girls; whereas waist-hip ratio was consistently the poorest predictor for them regardless of sex. Though the anthropometric indices were more predictive of dyslipidemia, hypertension and clustered risk factors in overweight/obese group compared to their normal BMI peers, the AUCs in overweight/obese group remained in the poor range below 0.70. CONCLUSIONS: Anthropometric indices are not effective screening tools for pediatric cardiometabolic risk factors, even in overweight/obese children.

Metabolic Syndrome and Related Factors in Chinese Children and Adolescents: Analysis from a Chinese National Study.

AIMS: Metabolic syndrome (MetS) has become a worldwide epidemic; however, few studies have described its status in Chinese children. This study aimed to estimate MetS status and its associations with geography, economic development, birth weight, and parental education of Chinese children and adolescents. METHODS: Data were derived from 15,045 participants aged 7-18 years across seven Chinese provinces. Physical measurement and blood tests were conducted to assess the five classical MetS components described by the International Diabetes Federation, including abdominal obesity (the essential component), high blood pressure, low high-density cholesterol (HDL-C), high triglyceride, and elevated fasting glucose (FG). Logistic regression was adopted to explore possible associations between MetS and other factors. RESULTS: Overall, MetS prevalence was 2.3%, higher in males (2.8% vs. 1.7% in females), northern regions (3.1%), more developed regions (2.9%), and older participants (aged 16-18 years) (P＜0.05 for all). Among the five MetS components, abdominal obesity and low HDL-C level were most prevalent (21.8% and 14.4%), and 35.9% of the participants had at least one component. In logistic regression, MetS itself did not correlate with birth weight or parental education. High birth weight was positively correlated with abdominal obesity (odds ratio, 1.48) butnegatively associated with elevated FG (odds ratio, 0.49). Concusions: MetS itself was not common in Chinese children and adolescents, whereas its certain components were far more prevalent. Children from North China, more-developed areas, and at an older age were more likely to develop MetS. Strategies designed to prevent pediatric MetS in China should focus on prevalent components as well as its geographic and economic development predilections.

Prevalence and risk factors of impaired fasting glucose and diabetes among Chinese children and adolescents: a national observational study.

The prevalence of impaired fasting glucose (IFG) and diabetes mellitus (DM) has reportedly increased significantly among Chinese children and adolescents. We aimed to examine the prevalence of IFG and DM, the disparities in sex and region and related risk factors among Chinese children and adolescents. A total of 16 434 Chinese children aged 6-17 years were selected from a national cross-sectional survey, and fasting glucose was measured for all participants. Overall, mean fasting plasma glucose (FPG) concentration was (4·64 (sd 0·51)) mmol/l, and the prevalence of DM and IFG was 0·10 and 1·89 %, respectively. Compared with girls, boys had higher FPG concentration (4·69 v. 4·58 mmol/l, r 0·107, P<0·001) and IFG prevalence (2·67 v. 1·07 %, r φ 0·059, P<0·001). Compared with rural children and adolescents, urban children and adolescent had higher FPG concentration (4·65 v. 4·62 mmol/l, r 0·029, P<0·001) and DM prevalence (0·15 v. 0·05 %, r φ 0·016, P<0·01). In addition, self-reported fried foods intake and overweight/obesity were positively associated with IFG, and the proportion of consuming fried foods more than or equal to once per week and overweight/obesity prevalence in boys and urban children and adolescents were significantly higher than girls and rural children and adolescents, respectively (P<0·05). Although the prevalence of IFG and DM was relatively low in Chinese children and adolescents, sex and region disparities were observed, which may be associated with differences in overweight/obesity prevalence and dietary factors.

[Prevalence of myopia and influencing factors among primary and middle school students in 6 provinces of China].

OBJECTIVE: To understand the prevalence of myopia in primary and middle school students in 6 provinces and the possible influencing factors. METHODS: Primary and middle school students were selected through multistage cluster sampling in 60 primary and middle schools in 6 provinces in China. The questionnaire survey and eyesight test were conducted among all the students selected according to the national student's physique and health survey protocol. Pearson chi-square test and binary multivariate logistic regression analysis were done to identify the influencing factors for myopia in students. RESULTS: The prevalence of myopia among primary and middle school students surveyed was 55.7%, the gender specific difference was statistically significant (59.7% for girls, 51.9% for boys) (P<0.01). The prevalence of myopia increased with age obviously. The prevalence was 35.8% in age group 6-8 years, 58.9% in age group 10-12 years, 73.4% in age group 13-15 years and 81.2% in age group 16-18 years, the differences were statistically significant (P<0.001). Single factor and multivariate analysis showed that parents' myopia, distance between computer screen and eyes, distance less than 30 cm between eyes and book while reading, distance less than 10 cm between chest and the table edge while studying, distance less than 3 cm between fingers and pen tip, sleep time, average outdoor activity time during last week, school sport activities in the afternoon, the size of television set at home, time spent on watching TV and playing computer were the influencing factors for myopia. CONCLUSIONS: The prevalence of myopia is till high in primary and middle school students. Myopia is associated with both genetic factors and individual eye health related behaviors.

A national school-based health lifestyles interventions among Chinese children and adolescents against obesity: rationale, design and methodology of a randomized controlled trial in China.

BACKGROUND: The prevalence of obesity among children and adolescents has been rapidly rising in Mainland China in recent decades, both in urban and rural areas. There is an urgent need to develop effective interventions to prevent childhood obesity. Limited rigid data regarding children and adolescent overweight prevention in China are available. A national random controlled school-based obesity intervention program was developed in the mainland of China. METHODS/DESIGN: The study was designed as a national multi-centered cluster randomized controlled trial involving more than 70,000 children and adolescents aged 7-18 years from 7 provinces in China. In each center, about 12-16 primary and secondary schools, with totally at least 10000 participants were randomly selected (Primary: Secondary = 1:1). All of the selected schools were randomly allocated to either intervention or control group (Intervention: Control = 1:1).The multi-components school-based and family-involved scheme was conducted within the intervention group for 9 month, while students in the control group followed their usual health practice. The intervention consisted of four components: a) Create supportive school and family environment, b) Health lifestyles education and related compulsory physical activities, c) Instruct and promote school physical education, d) Self-monitor obesity related behaviors. Four types of outcomes including anthropometric, behavioral, blood chemical and physical fitness were measured to assess the effectiveness of the intervention program. DISCUSSION: This is the first and largest multi-centered school-based obesity intervention program with the consideration of geographical and social-demographic characteristics of the rapidly increased obesity prevalence of Chinese children and adolescent. The intervention is based on Social Cognitive Theory and Social-Ecological Model of Health, and follows a stepwise approach guided by PRECEDE-PROCEED (P-P) Model and Intervention Map. The results of and lesson learned from this study will help guide future school-based national childhood obesity prevention programs in Mainland China. TRIAL REGISTRATION: January 22, 2015; REGISTRATION NUMBER: NCT02343588.