Matching actions to needs: shifting policy responses to the changing health needs of Chinese children and adolescents.

China is home to the second largest population of children and adolescents in the world. Yet demographic shifts mean that the government must manage the challenge of fewer children with the needs of an ageing population, while considering the delicate tension between economic growth and environmental sustainability. We mapped the health problems and risks of contemporary school-aged children and adolescents in China against current national health policies. We involved multidisciplinary experts, including young people, with the aim of identifying actionable strategies and specific recommendations to promote child and adolescent health and wellbeing. Notwithstanding major improvements in their health over the past few decades, contemporary Chinese children and adolescents face distinct social challenges, including high academic pressures and youth unemployment, and new health concerns including obesity, mental health issues, and sexually transmitted infections. Inequality by gender, geography, and ethnicity remains a feature of health risks and outcomes. We identified a mismatch between current health determinants, risks and outcomes, and government policies. To promote the health of children and adolescents in China, we recommend a set of strategies that target government-led initiatives across the health, education, and community sectors, which aim to build supportive and responsive families, safe communities, and engaging and respectful learning environments. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Associations between combinations of 24-h movement behaviors and physical fitness among Chinese adolescents: Sex and age disparities.

OBJECTIVE: To analyze the relationship between 24-h movement behaviors and adolescents' physical fitness, with sex difference and age disparity explored specifically. METHODS: A total of 135 852 Chinese adolescents aged 13-22 years were included in this cross-sectional study. Self-reported 24-h movement behavioral times, including moderate to vigorous physical activity (MVPA), recreational screen, and sleep, were identified as meeting guidelines based on Canadian recommendations. Physical fitness indicator (PFI) was calculated through sex- and age-specific z scores of body mass index, forced vital capacity, 50 m dash, sit-and-reach, standing long jump, body muscle strength, and endurance running, and then classified as: low level (<20th), middle level (20th-80th), and high level (>80th). Mixed effect logistic regression was applied to analyze the association, and interaction terms were constructed to prove the sex and age disparities. RESULTS: Only 12.4% of adolescents aged 13-22 years met all three recommendations. The number of meeting guidelines exhibited a typical dose-response relationship with high level PFI (OR = 1.22 [95% CI: 1.19-1.25]), and in detail, meeting MVPA + recreational screen (OR = 2.29 [95% CI: 2.09-2.51]) or MVPA-only (OR = 2.16 [95% CI: 1.93-2.41]) guidelines were better associated with high-level PFI. Besides, meeting MVPA-only guideline was proved with stronger association with high-level PFI for boys (p-interaction = 0.005). The dose-response relationship in boys of the number of guidelines met with PFI was stronger in 19- to 22-year-olds (p-interaction <0.001) and 16- to 18-year-olds (p-interaction = 0.001) than that in 13- to 15-year-olds. CONCLUSION: The prevalence of meeting 24-h movement behaviors guidelines among Chinese adolescents aged 13-22 years was relatively low. It was associated with adolescents' physical fitness, with meeting MVPA + recreational screen or MVPA-only guidelines bringing greater benefits, and sex difference and age disparity existing.

Secular trends and urban-rural disparities in the median age at menarche among Chinese han girls from 1985 to 2019.

BACKGROUND: Menarche is a substantial milestone of female puberty. Timing of age at menarche is considered the key to understanding the potential linkages with women's health outcomes later in life. This study aimed to explore the secular trends and urban‒rural disparities in the median age at menarche among Chinese Han girls from 1985 to 2019. METHODS: Data were extracted from the 1985, 1995, 2005, 2014, and 2019 Chinese National Surveys on Students' Constitution and Health, which were nationally representative cross-sectional studies, and a total of 173,535 Han girls aged 9-18 years were examined. Girls were asked whether menarche had occurred. The median age at menarche was estimated by probit analysis. Z tests were used to compare the differences between survey years and between urban and rural areas. RESULTS: The median age at menarche among Chinese Han girls decreased from 13.37 years in 1985 to 12.00 years in 2019, and the overall decrease was more significant in rural areas (1.77 years) than in urban areas (0.99 years). The average five-year change in the decrease in the median age at menarche showed an accelerating and then slowing pace; and it was observed similarly in both urban and rural areas. The urban‒rural disparities shrank from 0.64 years in 1985 to 0.44 years in 1995, then to 0.27 years in 2005, 0.24 years in 2014, and finally to - 0.14 years in 2019. CONCLUSIONS: The median age at menarche among Chinese Han girls continued to decline from 1985 to 2019 but at a slowing pace in the last five years. Urban‒rural disparities gradually narrowed. Sexual and reproductive health education and interventions to prevent the decline in the age of menarche are needed, especially in rural areas.

Secular trend and urban-rural disparity for age at spermarche among Chinese Han boys from 1995 to 2019.

AIM: To examine the secular trend and the urban-rural disparity of spermarche among Chinese Han boys from 1995 to 2019. METHODS: A total of 392 775 boys of Han ethnicity aged 11-18 years were extracted from the 1995, 2000, 2005, 2010, 2014 and 2019 Chinese National Surveys on Students' Constitution and Health. The median age at spermarche was estimated using the status quo data and probit analysis. The chi-square, ANOVA and LSD tests were used to compare the differences between the year-subgroups. U-test was used to compare the difference between urban and rural areas at each year. RESULTS: The median age at spermarche in Chinese Han boys decreased from 14.6 years in 1995 to 13.9 years in 2019 (p < 0.001). The rural boys showed a faster decreasing pace with a 1-year advance of age at spermarche while the urban boys had only a 0.5-year decrement, and there was still a statistically significant difference between urban-rural areas in 2019 (p < 0.001). Similar to urban-rural disparity, the age gap at spermarche between areas with different urbanisation rates became smaller over time. CONCLUSIONS: In general, spermarche in Chinese Han boys showed a decreasing trend, but the pace was slowing down. The urban-rural disparity in puberty development still existed but was gradually narrowing.

Coverage of school health monitoring systems in China: a large national cross-sectional survey.

BACKGROUND: There is growing interest in the role that schools can play in promoting student health. The aim of this study was to describe the coverage of school health monitoring systems for infectious diseases, non-communicable diseases, and school physical environments in China, and to explore differences by geography, regional wealth, and school type. METHODS: A cross-sectional study was performed using data from 2428 schools from 17 provinces in China in 2018. Data were collected using a questionnaire administered by the Ministry of Education through its monitoring system, and included infectious diseases (e.g., reporting system for student infectious diseases), non-communicable diseases (e.g., regular student health examinations), and school physical environments (e.g., monitoring of classroom light, microclimate and drinking water). FINDINGS: Overall, the coverage rate of full school health monitoring systems was 16·6%. The coverage rates of school health monitoring systems for infectious diseases, non-communicable diseases, and school physical environments were 71·2%, 68·5%, and 24·9%, respectively. Coverage was higher in schools from urban rather than rural areas, in schools from areas with greater wealth, and in senior secondary schools rather than junior secondary and primary schools. INTERPRETATION: Systems for monitoring infectious diseases in school students have been widely implemented in China. Systems for monitoring non-communicable diseases and physical environments need to be strengthened. Beyond greater attention in poorer and rural areas, increased investment in more comprehensive approaches to school health is indicated. FUNDING: This study was supported by National Statistical Science Research Project (2021LY052 to YS) and China Scholarship Council (201906015028 to PH).

Towards Comprehensive National Surveillance for Adolescent Health in China: Priority Indicators and Current Data Gaps.

PURPOSE: The purpose of the study was to propose a health indicator system responsive to current Chinese adolescent health needs and identify data gaps in current information systems. METHODS: We identified 186 keywords for adolescent health gathered from three sources: contributors to the burden of disease captured in the Global Burden of Diseases 2015, together with independent literature and expert desk reviews; major health-related policies released by the State Council of China; and global strategies issued by UN agencies over the past five years. All keywords were synthesized into indicators and ranked with core indicators identified through panel discussions and literature review. A further systematic review was conducted to identify data sources for each indicator. RESULTS: We identified 100 indicators which we categorized into five dimensions: health outcomes including adolescent mortality and morbidity; health knowledge, skills and risk behaviors including smoking, physical activity; demographic and socioeconomic status including education or employment; responsiveness of the health service system including the provision of health education at school; and the physical and social environments including safe drinking water, secondhand smoke exposure, injuries, and bullying. In total, 72 indicators had nationally representative data, including 22 out of 24 core indicators (91.7%), 27 out of 33 potential core indicators (81.8%), and 23 out of 43 general indicators (53.5%). A large proportion of these indicators rely solely on data from school or household surveys. CONCLUSIONS: The proposed health indicator system has the potential to rapidly identify shifting priorities for adolescent health in China but will require greater investment in primary data collection in neglected areas.

National and Subnational Trends in Mortality and Causes of Death in Chinese Children and Adolescents Aged 5-19 Years From 1953 to 2016.

PURPOSE: We aimed to analyze the recent trends of mortality and rankings of causes of death in Chinese children and adolescents from 1953 to 2016. METHODS: Data on mortality and causes of death in Chinese children and adolescents aged 5-19 years were extracted from the China Health Statistics Yearbook and the Global Burden of Disease Study from 1953 to 2016. Mortality variations were analyzed by year, age, sex, province, and causes of death. RESULTS: The mortality of Chinese children and adolescents aged 5-19 years declined steadily from 1953 (366.03/100,000) to 2016 (27.21), with the largest reduction in adolescents aged 15-19 years and the smallest reduction in those aged 10-14 years. Large subnational disparities for all-cause mortality existed in national 31 provinces with higher mortality in western regions compared with eastern regions, but with narrowing disparities between 1981 and 2010. Injuries dominated the causes of death compared with noncommunicable diseases and communicable, maternal and neonatal, and nutritional diseases from 1990 (58.13/100,000 vs. 32.10 and 14.31) to 2016 (22.65 vs. 13.00 and 2.93). In 2016, the leading three causes of death were road injuries (8.30/100,000), drowning (7.25), and leukemia (2.60). Drowning was the leading cause of death for 5- to 14-year-olds, but road injuries have been the leading cause for 15- to 19-year-olds of both sexes since 2010. CONCLUSIONS: Although mortality in Chinese adolescents now stands at just 7% of rates in the 1950s, there is a need to address continuing inequalities across sex, economic status, and region.

Ethnicity, socioeconomic status and the nutritional status of Chinese children and adolescents: Findings from three consecutive national surveys between 2005 and 2014.

BACKGROUND: Economic development has brought rapid shifts in the food environment of Chinese children and adolescents. OBJECTIVES: To assess the changes in childhood nutritional status across ethnic groups and economic status from 2005 to 2014. METHODS: 664 094 Chinese Han and 224 151 ethnic minority children and adolescents aged 7 to 18 years were assessed in three national cross-sectional surveys (2005, 2010 and 2014). Gross domestic product (GDP) per capita of each ethnic group was categorized into four strata of socioeconomic status. To assess ethnic disparities at each time point, we used logistic regression to estimate the prevalence odds ratios (OR) for thinness, overweight and obesity in the 24 ethnic minority groups vs Han Chinese. RESULTS: Children in the two upper economic strata (over about US$4000 GDP per capita) had a high prevalence of overweight and obesity, while those in the two lower economic strata (below US$4000 GDP per capita) had a high prevalence of thinness. From 2005 to 2014, the prevalence of thinness decreased from 18.6% to 13.1% in Han children, and from 20.4% to 17.1% in ethnic minority students. At the same time, the prevalence of overweight and obesity increased from 10.4% to 17.7% in Han children, and from 4.3% to 9.2% in ethnic minority students, respectively. CONCLUSIONS: A rapid nutritional transition has occurred from 2005 to 2014 with shifts from thinness to overweight and obesity in both Han and ethnic minority children and adolescents, reflecting local GDP per capita.

Reducing Anemia Among School-Aged Children in China by Eliminating the Geographic Disparity and Ameliorating Stunting: Evidence From a National Survey.

Background: The aim of this study was to assess the geographic disparity in anemia and whether stunting was associated with anemia in different geographic groups among school-aged children in China. Methods: 71,129 Han children aged 7, 9, 12, and 14 years old were extracted from the 2014 cycle of Chinese National Surveys on Children Constitution and Health. Anemia, anemia severity, and stunting were defined according to WHO definitions. Binary logistic regression models were used to estimate the association between anemia and stunting in different geographic groups. Results: The prevalence of anemia was significantly higher in girls (10.8%) than boys (7.0%). The highest anemia prevalence was in Group VII (lower class/rural, 12.0%). A moderate/severe prevalence of anemia was concentrated in Group VII and Group VIII (western/lower class/rural) for both sexes. The prevalence of anemia was higher in stunting boys than non-stunting boys in Group IV (lower class/city, χ2 = 12.78, P = 0.002) and Group VII (χ2 = 6.21, P = 0.018), while for girls, it was higher in stunting girls than their non-stunting peers only in Group II (upper class/large city, χ2 = 4.57, P = 0.046). Logistic regression showed that the stunting children have 30% higher risk of anemia than non-stunting children after adjustment for age, sex and school (OR = 1.30, 95% CI: 1.05-1.60). Conclusion: A significant geographic disparity and an association between anemia and stunting among specific groups of school-aged children in China was demonstrated. Consequently, eliminating the geographic disparity and ameliorating stunting might contribute to the improvement of Chinese children's anemia. Specific guidelines and interventions are needed, especially for adolescent girls and the groups with serious anemia burden.

The associations of economic growth and anaemia for school-aged children in China.

Economic growth has brought improvements in many areas of child health, but its effects on anaemia among school-aged children remain unknown. However, this is important because iron deficiency anaemia is common and is the main cause of disability-adjusted life years for school-aged children. In this study, we included 429,222 Chinese children aged 7-17 years from five consecutive national cross-sectional surveys during 1995-2014. Using altitude-adjusted haemoglobin concentration measured from capillary blood samples, we defined anaemia status according to World Health Organization's recommendation. We used logistic regressions weighted by provincial population to examine the association between provincial gross domestic product (GDP) per capita and anaemia, adjusting for sex, age, urban-rural location, regional socio-economic status (SES), fixed effect of province, and clustering of schools. We used generalised additive mixed models to evaluate a potentially non-linear relationship. For each 100% growth in GDP per capita, there was a 40% (odds ratio [OR] = 0.60; 95% confidence interval [CI; 0.56, 0.65]) reduction in anaemia. However, the association was weaker for girls and in cities with a lower SES. The association was weaker across 2005-2014 (OR = 0.75, 95% CI [0.62, 0.90]) compared with 1995-2005 (OR = 0.52; 95% CI [0.44, 0.61]), reflecting a weaker association when GDP per capita reaches around $2,000. The results were similar for moderate-to-severe anaemia. We concluded that economic growth has been associated with reductions in anaemia among school-aged children in China but with fewer benefits for girls and those in poorer settings. Further economic development in China is unlikely to bring similar reductions in anaemia, suggesting that additional population level and targeted interventions will be needed.

Secular Trends of Ascariasis Infestation and Nutritional Status in Chinese Children From 2000 to 2014: Evidence From 4 Successive National Surveys.

BACKGROUND: This study aimed to assess secular trends and epidemiological status of ascariasis infestations and to explore its effects on the nutritional transition among Chinese children from 2000 to 2014. METHODS: Data were collected from 69 435 Chinese children aged 7-year-olds and 9-year-olds in 4 successive cross-sectional surveys of Chinese National Survey on Students' Constitution and Health. Ascariasis infestation was defined by using the Kato-Katz method. Nutritional status was classified into stunting, thinness, overweight, and obesity by WHO definition. RESULTS: From 2000 to 2014, the ascariasis infestation rates decreased from 9.1% to 1.7%, the stunting and thinness prevalence decreased from 4.3% and 13.8% to 0.7% and 7.1%, while the overweight and obesity prevalence increased from 3.6% and 2.1% to 9.8% and 9.1%, respectively. Compared to children in the ascariasis noninfestation group, those infected with ascariasis had a worse nutritional status. Yet, the disparity in nutritional status between 2 groups disappeared over time. Provinces with a higher gross domestic product per capita simultaneously had lower ascariasis infestation rates, lower stunting and thinness prevalence, and higher overweight and obesity prevalence. CONCLUSIONS: The retardation effects caused by ascariasis infestation on nutritional status in Chinese children seemed to be offset by the rapid economic development and nutritional transition over time; nevertheless, multiple prevention and control measures are still needed and should be continuously strengthened.

Trends of age at menarche and association with body mass index in Chinese school-aged girls, 1985-2010.

OBJECTIVES: To estimate the shifts in age at menarche from 1985 to 2010, compare the differences of average age at menarche between urban and rural groups, and determine the association of menarche with body mass index (BMI). STUDY DESIGN: The data were obtained from 4 cross-sectional Chinese National Surveys on Students' Constitution and Health (1985, 1995, 2005, and 2010). In this representative sample of Chinese school-aged girls, the average age at menarche was determined using probit analysis and compared between urban and rural areas. Logistic regression was used to assess the association of BMI with the likelihood of having reached menarche. RESULTS: The age at menarche in Chinese girls dropped from 13.41 years to 12.47 years from 1985 to 2010. There was a significant difference in age at menarche between urban and rural girls over time, with urban girls having their menarche earlier than rural girls. Logistic regression showed that a higher BMI was strongly associated with an increased likelihood of having reached menarche, even after controlling for age, urban or rural residence, province, social economic status, and school. CONCLUSION: The analysis suggests a drop of about 4.5 months per decade in the average age at menarche over the past 25 years, and a significant inverse association between BMI and having reached menarche. Considering that both early menarche and higher BMI are significant risk factors for chronic diseases, and may act together in later years to the detriment of a woman's health, greater attention should be paid to the health of girls with earlier menarche and higher BMI.

[Changes of physical functions among Chinese minority students from 1985 to 2005].

OBJECTIVE: To study the changes of physical functions among minority students in China from 1985 to 2005, to provide evidence for health promotion to the minority students in the country. METHODS: Using data from the Chinese national survey on students physical fitness and health from 1985 to 2005, we analyzed the physical functions of 15 minority groups from primary and secondary schools, including Mongolian, Hui, Uygur, Zhuang, Korean, Tibetan, Yao, Li, Qiang, Buyi, Dong, Miao, Tu, Salar, Kirgiz, aged 7 - 18 years old. RESULTS: Some of the minority students had the higher levels of physiological functions and athletic ability, but some indicators decreased significantly. In terms of items related to 'speed', most of the minority boys and girls improved, but items related to 'endurance' or'vital capacity', were significantly declining. Part of the minority students had better 'endurance' than students of Han ethnicity in the cities. All the indicators of athletic ability declined in schoolboys and schoolgirls of Korean ethnicity. Kirgiz students were outstanding in vital capacity and speed quality while Uighur students had better physical development and vital capacity, but were poorer in running and jumping, reflecting the weakness of explosive power of lower limbs. On the contrary, Li and Zhuang students had shown a very good quality in running, jumping, male shoulder muscular strength and endurance items, etc. CONCLUSION: The physical functions and the athletic ability of the minority students in China had the advantages and characteristics, which might be related to their living environment and habits.