BACKGROUND: The urban-rural disparities in overweight and obesity among children and adolescents are narrowing, and there is a need for long-term and updated data to explain this inequality, understand the underlying mechanisms, and identify priority groups for interventions. METHODS: We analyzed data from seven rounds of the Chinese National Survey on Students Constitution and Health (CNSSCH) conducted from 1985 to 2019, focusing on school-age children and adolescents aged 7-18 years. Joinpoint regression was used to identify inflection points (indicating a change in the trend) in the prevalence of overweight and obesity during the study period, stratified by urban/rural areas and sex. Annual percent change (APC), average annual percent change (AAPC), and 95% confidence interval (CI) were used to describe changes in the prevalence of overweight and obesity. Polynomial regression models were used to predict the prevalence of overweight and obesity among children and adolescents in 2025 and 2030, considering urban/rural areas, sex, and age groups. RESULTS: The prevalence of overweight and obesity in urban boys and girls showed an inflection point of 2000, with AAPC values of 10.09% (95% CI: 7.33-12.92%, t = 7.414, P <0.001) and 8.67% (95% CI: 6.10-11.30%, t = 6.809, P <0.001), respectively. The APC for urban boys decreased from 18.31% (95% CI: 4.72-33.67%, t = 5.926, P = 0.027) to 4.01% (95% CI: 1.33-6.75%, t = 6.486, P = 0.023), while the APC for urban girls decreased from 13.88% (95% CI: 1.82-27.38%, t = 4.994, P = 0.038) to 4.72% (95% CI: 1.43-8.12%, t = 6.215, P = 0.025). However, no inflection points were observed in the best-fit models for rural boys and girls during the period 1985-2019. The prevalence of overweight and obesity for both urban and rural boys is expected to converge at 35.76% by approximately 2027. A similar pattern is observed for urban and rural girls, with a prevalence of overweight and obesity reaching 20.86% in 2025. CONCLUSIONS The prevalence of overweight and obesity among Chinese children and adolescents has been steadily increasing from 1985 to 2019. A complete reversal in urban-rural prevalence is expected by 2027, with a higher prevalence of overweight and obesity in rural areas. Urgent action is needed to address health inequities and increase investments, particularly policies targeting rural children and adolescents.
Humans ; Child ; Adolescent ; Female ; Male ; Rural Population/statistics & numerical data* ; Overweight/epidemiology* ; Prevalence ; China/epidemiology* ; Pediatric Obesity/epidemiology* ; Obesity/epidemiology* ; Urban Population

Objective: To explore the association between mental health and muscle strength among Chinese adolescents aged 13- 18, providing a theoretical foundation and intervention strategies for mental health promotion. Methods: Data were obtained from the 2019 Chinese National Survey on Students Constitution and Health, including 98 631 Chinese adolescents aged 13- 18. Psychological distress was assessed by using the Kessler Psychological Distress Scale (K10), and mental well being was measured with the Warwick-Edinburgh Mental Well being Scale (WEMWBS). Based on the gender and age specific Z scores of various test items [grip strength, standing long jump, pull ups (for males), and sit ups (for females)], muscle strength index (MSI) was constructed to evaluate the comprehensive level of muscle strength in adolescents. According to the Dual factor Model (DFM) of mental health, participants were categorized into four groups:troubled, symptomatic but content, vulnerable, and complete mental health. Gender differences were analyzed by using Chi-square tests, trends were tested with Cochran-Armitage tests, and multinomial Logistic regression models were applied to assess associations between muscle strength and mental health among adolescents. Results: In 2019, 37.4% of Chinese adolescents aged 13-18 were reported of high mental distress, and 59.9% were reported of low mental well being. Boys had significantly lower rates of high mental distress (35.3%) and low mental well being (55.6%) compared to girls (39.4%, 64.3%), and the differences were of statistical significance ( χ 2=176.13, 780.42, both P <0.05). In 2019, the rate of complete mental health among adolescents showed a downward trend with increasing age ( χ 2 trend = 258.47) and a gradual upward trend with increasing muscle strength levels ( χ 2 trend =123.14)，and both boys and girls exhibited similar trends ( χ 2 trend =103.83, 168.46; 57.00 , 67.34) (all P <0.05). The results of the unordered multiclass Logistic regression model showed that after controlling for confounding factors such as age and gender, when the completely pathological group as a reference, for every 1 unit increase in MSI in adolescents, the likelihood of being in a completely mental health state increased by 29% ( OR = 1.29); for every unit increase in the Z-score for pull ups, the likelihood of being in a completely mental health state increased by 6% ( OR =1.06) among boys; for every 1 unit increase in sit up Z score, the likelihood of being in a completely mental health state increased by 19% ( OR =1.19) among girls (all P <0.05). Conclusions The mental health status of Chinese adolescents is not good enough. Muscle strength is positively associated with mental health.

Objective: To systematically review the development and changes in mental health policies within the National Outline for Children s Development in China from 1992 to 2030, providing a reference basis for future formulation of mental health policies among children and adolescent in China. Methods: Based on the four editions of the National Outline for Children s Development in China across different periods from 1992 to 2030, word frequency analysis was used to reveal shifts in policy priorities, and an internationally recognized framework for adolescent health policy analysis was applied to conduct a textual review. Results: Word frequency analysis revealed that the term "psychological" appeared 6 times in the National Outline for Children s Development in China (2001-2010) but increased to 20 times in the National Outline for Children s Development in China (2021-2030) (abbreviated as the National Outline of 2021), while the term "health" rose from 4 times in the National Outline for Children s Development Plan in China in the 1990s to 68 times in the National Outline of 2021. The scope of mental health policy interventions expanded to encompass five key areas:health, safety, education, welfare and legal protection. Textual analysis highlighted that the policies of the National Outline for Children s Development in China were demand driven, prioritized vulnerable groups and continuously broadened their coverage, emphasizing sustainability and appropriateness, and monitoring/evaluation mechanisms. By 2023, 42.3% of primary schools and 64.8% of secondary schools employed full time mental health education teachers. However, the National Outline for Children s Development in China lacked direct evidence of children and adolescents participation in policy formulation, and publicly available mental health data disaggregated by age and gender remained limited. Conclusion Mental health policies of children and adolescents in China have evolved from nonexistence to gradual refinement, yet institutionalized channels for youth involvement in policy development and evaluation remain insufficient, and transparency in age and gender specific mental health data needs improvement.

Objective:To describe the current distribution of daily physical activity time among ele-mentary and junior high school students in Beijing,and to analyze the influencing factors and pathways at the individual,family,school and community levels.Methods:Data were drawn upon from a cross-sectional investigation in Beijing in 2023,and a total of 3 157 elementary and junior high school students were included in the final analysis.Questionnaire was used to collect data on basic characteristics,over-all and in-school physical activity time per day,the number of sports mastered,perceived physical activi-ty benefits and barriers scales,perceived family,school,and community physical activity supportive en-vironment scales.Log-binomial regression model was used to analyze the associations between physical activity time and influencing factors,and structural equation modeling was used for the path analysis of the influencing factors.Results:The reported rates of ≥ 2 hours of overall physical activity per day and≥1 hour of physical activity in school per day among elementary and junior high school students in Beijing in 2023 were 33.1％and 64.8％,respectively.The associations between the number of sports mastered by students and the reported rate of ≥2 hours of overall physical activity per day showed a typical dose-response relationship(P-trend＜0.001).The perceived physical activity benefits-to-barriers ratio(PR=1.24,95％CI:1.20-1.28),scores of perceived family,school,and community physical acti-vity supportive environment scales were all positively associated with the reported rate of≥2 hours of overall physical activity per day(PR=1.51,95％CI:1.38-1.66;PR=1.50,95％CI:1.37-1.64;PR=1.21,95％CI:1.16-1.27).The structural equation modeling showed that the number of sports mastered by the students(β=0.11,P＜0.001),perceived physical activity benefits-to-barriers ratios(β=0.15,P＜0.001),and scores of supportive environment scales consisting of family,school,and community(β=0.13,P＜0.001)were associated with the reported rates of ≥2 hours of overall physi-cal activity per day directly.In addition,the scores of supportive environment scales could indirectly in-fluence the reported rates of ≥2 hours of overall physical activity per day by influencing the number of sports mastered by the students(β=0.21,P＜0.001)and the perceived physical activity benefits-to-barriers ratio(β=0.56,P＜0.001),while the number of sports mastered by the students could indi-rectly influence the reported rates of ≥2 hours of overall physical activity per day by influencing the per-ceived physical activity benefits-to-barriers ratios(β=0.05,P=0.003).The influencing factors and pathways of the reported rates of ≥ 1 hour of physical activity in school per day were similar with those of the reported rates of ≥2 hours of overall physical activity per day described above.Conclusion:The dai-ly physical activity time among elementary and junior high school students in Beijing in 2023 fell short of meeting the national requirement.There was a need to build a supportive environment consisting of fami-ly,school,and community for physical activity,to promote the students'sports skills,to establish the idea of independent physical activity,and to ensure that primary and secondary school students were given one hour of physical activity time every day,both inside and outside the school.

Objective: To analyze the prevalence of comorbidity of spinal curvature abnormality and malnutrition among primary and secondary school students aged 10-18 years in Tianjin in 2023, so as to provide scientific basis for the combined prevention of common diseases and multiple diseases among students and the construction of school health system. Methods: In September to October 2023, 31 884 primary and secondary school students aged 10 to 18 years in Tianjin were selected using stratified cluster random sampling. Abnormal spinal curvature in children and adolescents was assessed by Sereening of Spinal Curvature Abnormality of Children and Adolescents, while stunting, wasting, overweight, and obesity were determined according to the Screening for Malnutrition among Schoolage Children and Adolescents and Screening for Overweight and Obesity among Schoolage Children and Adolescents. The χ2 test was used to compare betweengroup differences in coprevalence, and multiple Logistic regression models were used to analyze the risk of different comorbidity types in different clusters. Results: The coprevalence of spinal curvature abnormality and malnutrition among primary and secondary school students in Tianjin was 1.6%, which was higher for girls than boys (1.8%, 1.4%), higher (2.5%) for senior high schools than for junior high schools and elementary schools (2.0%, 0.5%), and higher in rural than in urban areas (2.1%, 1.1%) (χ2=9.45, 141.92, 46.94, P<0.05). Multiple Logistic regression models showed that junior high school girls had a higher risk of incorrect posture comorbid with stunting and wasting (OR=4.52, 95%CI=1.84-11.06) and incorrect posture comorbid with overweight and obesity (OR=2.67, 95%CI=1.74-4.10) than boys, and that scoliosis/sagittal spinal abnormality comorbid with stunting and wasting (OR=0.10, 95%CI=0.02-0.44) risk was lower than that of boys, senior high school girls had a lower risk of scoliosis/sagittal spinal abnormality comorbid with overweight and obesity (OR=0.27, 95%CI=0.11-0.66) (P<0.05). Conclusions The coprevalence of spinal curvature abnormality and malnutrition is specific among primary and secondary school students in Tianjin, and the comorbidity type varies by gender and education stage. There is a need to increase prevention and control of spinal curvature abnormalities in school health working, intensive screening of key populations, and timely intervention.

Objective: To describe the current status of the prevalence of co-morbid myopia and obesity among 7-18 years students in the Inner Mongolia Autonomous Region in 2021 and to analyze the moderating effect of lifestyle in this association ，so as to provide scientific basis for the establishment of the mechanism of Co-morbidity，Shared Etiology，and Shared Prevention of common diseases in children and adolescents. Methods: A total of 139 630 primary and secondary school students aged 7-18 years from Inner Mongolia Autonomous Region were selected by stratified random cluster sampling method in September,2021. Myopia was determined using distance visual acuity examination and refractive error examination, and obesity was determined according to the BMI classification criteria for overweight, obesity screening of Chinese school age children and adolescents. Used a questionnaire, healthy lifestyles were determined according to the American Heart Association s Healthy Lifestyle Score by totaling the six scores for smoking, alcohol consumption, diet, exercise, screen time, and sleep duration.The χ 2 test was used to compare the association between group differences in the co-morbidity rate of myopia and obesity. The multivariable Logistic regression model was used to explore the influencing factors of the co-morbidity of myopia and obesity, and the stratified analysis was used to analyze the moderating effect of lifestyles on the prevalence of the co-morbidity. Results: The prevalence of myopia and obesity co-morbidity among students aged 7-18 years old in the Inner Mongolia Autonmous Region in 2021 was 13.7%, higher among boys than girls ( 15.5 % vs. 11.8%), higher among those aged 10-12 years old than 7-9,13-15,and 16-18 years old (14.7%,13.7%, 13.3%, 12.0%), higher among other ethnic minorities than Han Chinese and Mongolians (15.3%, 14.0%, 12.5%), higher in urban areas than that in suburban areas(15.3%, 13.0%), and middle economic level tracts were higher than poor and good tracts (14.8%, 12.9 %, 12.6%) ( χ 2=392.37，115.73，62.80，119.02，121.60, P <0.05). Multivariable Logistic regression modeling showed that unhealthy lifestyles ( OR=1.24, 95%CI=1.19-1.29 ) and middle level of lifestyle score ( OR=1.15, 95%CI=1.10-1.19 ) students had higher prevalence of co-morbidity, and the results were statistically significant among both boys and girls, the age groups of 10- 12, 13-15, and 16-18 years old, as well as the Han and Mongolian ethnic groups (all P <0.05). Conclusion In 2021, the current situation of myopia and obesity co-morbidity and unhealthy lifestyles among primary and secondary school students in the Inner Mongolia Autonomous Region are not optimistic.

Objective: To analyze the hotspots, frontiers, and future research trends related to puberty development among children and adolescents from 2013 to 2022, and to provide a reference for subsequent research related to puberty development. Methods: Data related to puberty development from 2013 to 2022 were retrieved from the Web of Science core collection with the search formula "puberty timing (title) OR puberty development (title) OR pubertal timing (title) OR pubertal development (title) OR puberty timing (abstract) OR puberty development (abstract) OR pubertal timing (abstract) OR pubertal development (abstract)". The CiteSpace was used for visual analysis. Results: A total of 6 684 publications were obtained and an upward trend could be seen in the number of publications in the field of puberty development in the last 10 years. Researchers with a high number of publications were Juul Anders, Brix Nis, and Ernst Andreas, in addition, the United States had the highest number of publications ( 2 125 ) and the highest betweenness centrality (0.23) in this field. In the last decade, research hotspots had focused on the timing of pubertal initiation, biological mechanisms of pubertal development, and sex differences in pubertal development. Research on environmental endocrine disruptors and the mechanisms of pubertal development were at the forefront of research and future research trends. Conclusion Scholars can refer to the research hotspots and research trends in this field and focus on the issues related to environmental endocrine disruptors and pubertal development mechanisms.

Objective:To describe the prevalence of psychological distress and to analyze its influencing factors among Chinese children and adolescents aged 9-18 years in 2019.Methods:Data was from the 2019 Chinese National Survey on Students' Constitution and Health, and 148 892 children and adolescents were included. Psychological distress was measured using the Kessler Psychological Distress Scale (K10): scores ≤19 were defined as no psychological distress, scores between 20-24 were defined as mild psychological distress, scores between 25-29 were defined as moderate psychological distress, and scores ≥30 were defined as severe psychological distress (moderate to severe psychological distress were defined as high psychological distress). The ANOVA, t test, and χ2 test were used to compare the differences in K10 scores and high psychological distress rates among children and adolescents with different characteristics. The ANOVA and trend χ2 test were used to analyze the trends. Modified-Poisson regression models were used to determine influencing factors of high psychological distress. Results:The K10 scores for Chinese children and adolescents aged 9-18 years in 2019 was 21.5±9.2, and their rate of high psychological distress was 31.6%. The rates of high psychological distress among children and adolescents aged 9-12, 13-15, and 16-18 years were 22.3%, 35.9%, and 38.8%. K10 scores and rates of high psychological distress showed an increasing trend as age increased (trends test all P<0.001). K10 scores and rates of high psychological distress were higher among children and adolescents who were older, female, rural, in areas with medium to low GDP per capita level, and with lower parental education (all P<0.001). Multifactorial modified-Poisson regression analysis showed that children and adolescents aged 13-15 years, 16-18 years, female, rural, and in areas with low to moderate GDP per capita level were at higher risk of high psychological distress (all P<0.05), with a OR (95% CI) of 1.55 (1.52-1.58), 1.66 (1.63-1.69), 1.07 (1.05-1.09), 1.02 (1.01-1.04), 1.10 (1.07-1.12). Children and adolescents in areas with medium to high GDP per capita level, whose father had a secondary or high school degree, whose father had a college degree or above, whose mother had a secondary or high school degree, and whose mother had a college degree or above were at lower risk of high psychological distress (all P<0.05), with a OR (95% CI) of 0.96 (0.94-0.98), 0.92 (0.90-0.93), 0.84 (0.82-0.86), 0.95 (0.93-0.97), 0.86 (0.83-0.88). Conclusions:The prevalence of psychological distress was high among Chinese children and adolescents aged 9-18 years in 2019, which is a vital problem. Mental health interventions need to be implemented among children and adolescents that were older, girls, rural, live in areas with lower economic levels, and whose parents have a lower education level.

Objective:To analyze the association between the occurrence of spermarche and menarche and psychological distress among Chinese Han children and adolescents aged 9 to 18 years.Methods:Data were drawn from the 2019 Chinese National Survey on Students' Constitution and Health, and a total of 54 438 boys aged 11 to 18 years and 76 376 girls aged 9 to 18 years with psychological distress, spermarche/menarche records were included in the final analysis. The occurrence of spermarche/menarche was recorded by physicians, and psychological distress was classified according to the Kessler Psychological Distress Scale scores. The chi-square test was used to compare the difference between groups in the occurrence of spermarche/menarche, and the multinomial logistic regression model and stratification analysis was established to analyze the association between psychological distress and spermarche/menarche.Results:The incidence of spermarche/menarche in 2019 ranged from 6.3% to 96.5% for eight age groups of Chinese boys and 2.8% to 99.0% for ten age groups of girls. The rates of high psychological distress among boys and girls were 32.5% and 32.7%. Among boys aged 11 to 18 years, the rate of high psychological distress increased with age, with a trend test P<0.001, and the difference in the rate of high psychological distress between those who had and had not had their spermarche was not statistically significant in all age groups. Among girls aged 9 to 18 years, the rate of high psychological distress increased with age, with a trend P<0.001; the rate of high psychological distress was higher in the group with menarche at age 10 and 12 than in the group without menarche (all P<0.05). High psychological distress was positively correlated with spermarche among boys aged 13-15 years living in urban areas and hight level economic development areas ( OR=1.11, 95% CI: 1.02-1.21; OR=1.18, 95% CI: 1.06-1.32). Overall, high psychological distress was positively correlated with menarche in girls aged 9-12 and 13-15 years ( OR=1.33, 95% CI: 1.25-1.42; OR=1.22, 95% CI: 1.07-1.39). High psychological distress was positively correlated with menarche among girls aged 9-12 years living in different regions except for the Northeast region, in areas with different levels of economic development, and in urban and rural areas, in girls aged 13-15 years living in urban, central, and western regions, and in girls aged 16-18 years residing in the central region. Conclusions:This study found an association between the occurrence of spermarche/menarche and psychological distress among Chinese Han children and adolescents aged 9 to 18 years in 2019, which was particularly significant among girls aged 9 to 12 years and boys aged 13 to 15 years living in areas with higher levels of socioeconomic development.

Objective:To describe the status of physical fitness of children and adolescents aged 13-18 years in China in 2019 and analyze its association with psychological distress.Methods:Data were drawn from the 2019 Chinese National Survey on Students' Constitution and Health, and 90 633 Han children and adolescents aged 13-18 years were included. Physical fitness was evaluated by "National Students Constitutional Health Standards" (2014 revised edition). Psychological distress was classified according to the scores of the Kessler Psychological Distress Scale: ≤19, 20-24, 25-29, and ≥30 scores indicated no, mild, moderate, and severe psychological distress, respectively, with moderate and severe psychological distress collectively referred to as high psychological distress. The χ2 test was used to compare the distribution differences between boys and girls, the Cochran-Armitage test was used to analyze the trend, and the multinomial logistic regression in the mixed effect model was established to analyze the association between physical fitness and psychological distress. Results:In 2019, the unqualified rate of physical fitness among children and adolescents aged 13-18 years in China was 17.2%, and the prevalence of excellent and good physical fitness was 18.2%, which was lower among boys (15.9%) than girls (20.5%) with a statistically significant difference ( P<0.05). The excellent and good physical fitness rate showed a significantly decreasing trend with age (trend test P<0.05). The rate of high psychological distress among children and adolescents aged 13-18 years in China in 2019 was 39.3%, with boys (37.0%) having a lower prevalence than girls (41.6%), supported by a statistically significant difference ( P<0.05), and a decreasing trend with the degree of physical fitness was observed both in boys and girls (trend test P<0.05). The multinomial logistic regression model showed that the prevalence of moderate ( OR=0.83, 95% CI: 0.79-0.88, P<0.001) and severe ( OR=0.81, 95% CI: 0.77-0.86, P<0.001) psychological distress were both lower in children and adolescents with excellent and good physical fitness. Conclusion:The status of physical fitness and psychological distress of Chinese children and adolescents aged 13-18 in 2019 was not optimistic, with physical fitness showing a significantly negative association with psychological distress.