To investigate the distribution characteristics and related factors of weight loss behavior among middle school students in Shanghai, so as to provide a reference for guiding scientific weight loss among middle school students.

From May to June 2021, a stratified cluster random sampling method was used to select 16 758 junior and high school students in 16 districts of Shanghai. Youth Risk Behavior Surveillance System was administered to assess the basic condition and weight loss behaviors of the students. An unordered multinomial Logistic regression model was employed to analyze the factors associated with weight loss behaviors.

A total of 5 881 (35.09%) reported engaging in exercise for weight loss, 6 344 (37.86%) reported dieting for weight loss, and 461 (2.75%) engaged in unhealthy weight loss behaviors. The unordered multinomial Logistic regression analysis indicated that compared with the no-weight-loss behavior group, students from urban areas(OR=1.35, 95%CI=1.10-1.66), those with Internet addiction (OR=1.71, 95%CI=1.23-2.38), those with victims of bullying (OR=2.09, 95%CI=1.68-2.61), those experiencing insomnia (OR=2.33, 95%CI= 1.74-3.11), those feelings of sadness or despair (OR=3.10, 95%CI=2.42-3.97), and those who perceived their body weight as slightly heavy (OR=2.77, 95%CI= 2.17-3.55) or very heavy (OR=3.41, 95%CI=2.44-4.75) were more likely to engage in unhealthy weight loss behaviors (P<0.05).

There are significant differences in weight loss behaviors among middle school students with varying characteristics in Shanghai. Negative emotions such as insomnia and feelings of sadness or despair, Internet addiction, cognitive bias in weight and experiences of bullying are identified as related factors for unhealthy weight loss behaviors. Targeted intervention measures should be implemented to guide students towards scientific approaches to weight management.

To explore the effects of potential categories of cumulative ecological risk on academic engagement, so as to provide theoretical basis for promoting academic engagement among vocational college students.

In May 2024, a convenience sampling method was used to select 1 666 students from three grades of six vocational colleges in Xuzhou City, Jiangsu Province. A survey was conducted on the cumulative ecological risk and academic engagement, and latent profile analysis was used to explore the potential categories of cumulative ecological risk and test its effect on academic engagement.

There were four latent classes of cumulative ecological risk among vocational college students, namely, complete family-low risk group, complete family-medium risk group, incomplete family-medium risk group, complete family-moderate to high risk group, accounting for 11.8%, 44.8%, 21.0% and 22.4%. There were significant differences in academic engagement among different potential categories of cumulative ecological risk of students (F=138.03, P<0.01), with the highest level of academic engagement in the complete family-low risk group (102.95±15.74), followed by the complete family-medium risk group (87.67±14.26), incomplete family-medium risk group (84.53±19.25) and complete family-moderate to high risk group (73.24±20.13). The potential categories of cumulative ecological risk significantly predicted academic engagement (P<0.01). When the complete family-low risk group was used as a reference, the regression coefficients for the complete family-medium risk, incomplete family-medium risk, and complete family-moderate to high risk were -0.40, -0.40 and -0.65, respectively.

The potential categories of cumulative ecological risks among vocational college students significantly predict their academic engagement, and vocational colleges need to pay attention to the cumulative ecological risks and different potential categories of students when promoting their academic engagement.

To analyze the issuance of Chinese adolescents mental health promotion policies and policy objects, and to explore the use of different object policy tools and the effectiveness of the policy, so as to provide reference for the improvement of the subsequent policy.

Adolescents' mental health promotion policies published and policy documents that included adolescents in mental health promotion policies and regulations in China from 2014 to the present were obtained, with the search period of July to August 2024. Policy content and effectiveness were analyzed by using content cross-tabulation analysis and Policy Modeling Consistency Index Model (PMC index model). It coded with Nvivo 20 software to understand the types of tools that policy depends on.

A total of 41 documents were included. The number of adolescent mental health promotion policy texts rose by year, most of which were issued independently, accounting for 70% of the total number of texts issued; 30% were jointly issued, with the Ministry of Education and the National Health Commission as the core subjects. Supply-type policy tools accounted for 47.45% of the total, while environment-type and demand-type policy tools accounted for 29.68% and 22.87% respectively; the use of policy tools by different policy targets varies, with families and social organizations using more supply-type and demand-type policy tools, while the education system and healthcare institutions were more inclined to supply-type policy tools, and the government departments were more inclined to supply-type policy tools and environment-type policy tools. In terms of policy effectiveness, there was a common problem of a lack of incentives and constraints, and the PMC values of two long-term planning mental health policies were high (7.76, 7.56), and both reached the excellent level.

China has paid more attention to adolescents' mental health, and the basic guarantees have been established and overall policy effectiveness is good, but the use of policy tools is uneven. There is a need to improve the operational content of medium- and long-term policies and to strengthen synergies between implementing departments.

To explore the association between vitamin D levels and sleep in children and adolescents, so as to provide a reference for promoting the sleep health of children and adolescents.

From October to December, 2021, 4 827 primary and middle school students aged 6-17 in Shenzhen were selected by multistage cluster random sampling method, and their demographic information, family background, lifestyle and sleep status were obtained by face-to-face questionnaire survey, and their fasting venous blood in the morning was collected to detect the serum 25(OH)D level. The relationship between serum vitamin D level and sleep characteristics was analyzed by binary Logistic regression, and stratified analysis was carried out according to gender.

The proportion of vitamin D deficiency was 41.1%, and the proportion of sleep deficiency was 19.4%. With the increase of vitamin D level, daily sleep duration of children and adolescents tended to increase (r=0.10, P<0.01). After adjusting for covariates such as gender and age, it was found that children and adolescents with insufficient vitamin D levels were more likely to experience sleep insufficiency, social jetlag, and late sleep on weekdays, with ORs being 1.32(95%CI=1.12-1.56), 1.35(95%CI=1.19-1.54), and 1.26(95%CI=1.05-1.52)(P<0.05). Sex-stratified analysis showed that, among boys, vitamin D deficiency was associated with sleep deficiency, social jetlag, and late bedtime on weekdays and weekends[OR(95%CI)=1.42(1.14-1.77), 1.25(1.04-1.49), 1.39(1.06-1.82), 1.86(1.19-2.92), P<0.05]. In girls, however, serum vitamin D levels were only associated with social jetlag with OR being 1.47 (95%CI=1.21-1.79, P<0.05).

Vitamin D levels are associated with various sleep characteristics in children and adolescents, with this association being more pronounced among boys.

To analyze the relationship between 24 h movement behaviors and cognitive function in children and adolescents, as well as the isotemporal substitution benefits, in order to provide a basis for developing cognitive development intervention strategies among children and adolescents.

Relevant studies were searched in the Web of Science, PubMed, Embase, EBSCO, and China National Knowledge Infrastructure databases from their inception to November 30, 2024. Systematic evaluation was performed after document screening, data extraction and quality assessment.

A total of 24 high-quality studies were included, comprising 35 295 children and adolescents aged 3-18 years. Adhering to the 24 h activity guidelines was associated with better cognitive performance (19 studies). Additionally, substituting 5-30 minutes per day of moderate to vigorous physical activity (MVPA) or sleep (SLP) for sedentary behavior (SB) or light physical activity (LPA) were associated with improvements in cognitive function (7 studies). There were inconsistencies in the effects of different types of SB (learning or entertainment) on cognitive function.

Adherence to the 24 h activity guidelines supports cognitive development in children and adolescents, with MVPA and SLP as key intervention targets. Increasing the proportion of MVPA, ensuring adequate SLP, and limiting recreational SB and screen time might be helpful to enhance the combined benefits of these three behaviors.

To explore the role of outdoor activity in the relationship between infancy responsive caregiving trajectories and early childhood development, so as to provide a theoretical basis for the promotion of early child development.

The study participants were drawn from the Shanghai Maternal-Child Pairs Cohort and 4 723 mother-child pairs who completed responsive caregiving questionnaires at 2, 6 and 12 months old were included. Questionnaires were used to assess children's responsive caregiving and average daily hours of outdoor activity at 2 years of age. The Age-Stage Questionnaire, Third Edition (ASQ-3) was used to evaluate children's development problems at 2-5 years old. Group-based trajectory model was applied to fit infancy responsive caregiving trajectory. Modified Poisson regression was used to analyze associations between different responsive caregiving trajectory groups and child development, and moderating effects were tested for hours of outdoor activity.

Infancy responsive caregiving trajectories were categorized into general group (n=3 871), declining group(n=160), and fluctuating group(n=646). After adjusting for confounding factors, such as parents' educational level, annual household income, maternal progestation body mass index, maternal tobacco exposure during pregnancy, maternal anxiety and depression during pregnancy, maternal age at delivery, maternal gestational age, maternal mode of delivery, children's gender, children's birth weight, and duration of breastfeeding, the results of modified Poission regression analysis showed that compared with the general group, children at the age of 2 in declining and fluctuating group had increased risks of suspected developmental delays in communication, gross motor, fine motor, problem solving, and personal-social scales (OR=1.41, 1.31, 1.35, 1.23, 1.21;1.07, 1.08, 1.08, 1.09, 1.06);but children only had increased risk of suspected developmental delays in communication of declining group (OR=1.08), personal-social scales of fluctuating group (OR=1.06) at 3-5 years of age (P<0.05). At lower levels of outdoor activity, children in fluctuating group had reduced scores in communication (β=-1.41), fine motor (β=-2.34), problem solving (β=-1.11) and personal-social scales (β=-1.99) as compared to general group; and children in declining group had reduced scores in gross motor (β=-4.78)(P<0.05). While at higher levels of outdoor activity, no differences were found between children in fluctuating, declining groups and those in general group in scores of different scales (P>0.05).

Prolonged outdoor activity attenuates the adverse effects of declining and fluctuating trajectories of infancy responsive caregiving on early childhood development.

To analyze the trajectories of blood pressure and body mass index (BMI) among primary and secondary school students aged 7-17 in Shunyi District of Beijing, and to explore the association between different growth trajectories and visual outcomes, so as to provide a scientific basis for the prevention and control of common diseases in children and adolescents.

Health examination data (including vision, blood pressure and BMI) of primary and secondary school students in Shunyi District of Beijing from 2019 to 2023 were collected and analyzed. Group-based trajectory modeling was used to classify the trajectories of BMI and blood pressure (systolic and diastolic) into distinct groups among students aged 7-17 years. The relationship between these trajectories and visual outcomes was examined using binary Logistic regression analysis.

The prevalence of screening myopia among students in Shunyi District was 57.2%, while the rate of moderate to severe visual impairment was 55.8%. Based on the latent growth model, the trajectories of systolic blood pressure, diastolic blood pressure, and BMI were divided into three groups: low-growth trajectory, moderate-growth trajectory and high-maintenance trajectory. Logistic regression analysis revealed that, compared to the low-growth trajectory group, the moderate-growth and high-maintenance trajectory groups for systolic blood pressure, diastolic blood pressure, and BMI were associated with an increased risk of screening myopia (OR=1.14, 1.11; 1.07, 1.19; 1.06, 1.08, P < 0.05). Similarly, the moderate-growth and high-maintenance trajectory groups for systolic blood pressure, diastolic blood pressure, and BMI were similarly associated with an increased risk of moderate to severe visual impairment (OR=1.12, 1.12; 1.09, 1.17; 1.08, 1.11, P < 0.05).

Moderate-growth and high-maintenance trajectories of blood pressure and BMI are associated with an increased risk of screening myopia and moderate to severe visual impairment among students. It is recommended to closely monitor changes in blood pressure and overweight/obesity trajectories in primary and secondary school students, conduct regular assessments, and actively prevent the development and progression of multimorbidity and comorbidity.

To understand 24 h physical activity levels of children aged 8-9 years in Pudong New Area and to explore its association with metabolic syndrome, so as to provide scientific basis for children's participation in physical activities and reducing the risk of metabolic syndrome.

A stratified cluster random sampling method was adopted to select 13 schools in Pudong New Area, Shanghai. A total of 2 013 primary school students aged 8-9 years old were included as the research subjects. During September 2021 to December 2022, Actigraph GT3X accelerometer, height measuring gauge, electronic sphygmomanometer and waist circumference tape was used to measure physical activity, height, blood pressure and waist circumference, respectively. A total of 5 mL of venous blood was collected from students, and the levels of triglycerides (TG), high-density lipoprotein cholesterol (HDL-C) and fasting plasma glucose (FPG) were detected, and online questionnaires were conducted. The t-test and one-way ANOVA were employed to compare the differences in 24 h physical activity levels among children with different characteristics. Multivariate Logistic regression was used to analyze the association between the 24 h physical activity levels and metabolic syndrome as well as its components.

Among primary school students, the average daily time of moderate to vigorous physical activity (MVPA) was (34.25±13.49)min, the attainment rate was 1.59%. The average daily sleep (SLP) time was (538.27±28.53) min, attainment rate was 1.89%. The detection rates of metabolic syndrome, abdominal obesity (AO), elevated blood pressure (BP), elevated TG, low HDL-C, and elevated FPG were 2.48%, 34.53%, 10.38%, 10.73%, 1.24% and 0.70%, respectively. Multivariate Logistic regression analysis showed that, for every 10-minute increase in sedentary behavior (SB) time, the risks of AO, elevated BP, and elevated TG increased by 2% (OR=1.02, 95%CI=1.01-1.04), 5% (OR=1.05, 95%CI=1.01-1.08), and 6% (OR=1.06, 95%CI=1.02-1.11), respectively (P < 0.05). For every 10-minute increase in MVPA time, the risk of metabolic syndrome decreased by 27% (OR=0.73, 95%CI=0.57-0.93, P < 0.05). For every 10-minute increase in SLP time, the risks of AO, elevated BP, and metabolic syndrome decreased by 16% (OR=0.84, 95%CI=0.80-0.88), 9% (OR=0.91, 95%CI=0.82-0.99), and 15% (OR=0.85, 95%CI=0.77-0.94), respectively (P < 0.05).

The time of MVPA and SLP are seriously insufficient among children aged 8-9 years in Pudong New Area. There is an association between physical activity levels and metabolic syndrome as well as its components. Increasing the time of MVPA and SLP is of great significance for maintaining a relatively low risk of metabolic syndrome in children.

To analyze the burden of bipolar disorder among adolescents aged 10-24 in China from 1990 to 2021 and its trend of change, so as to provide theoretical basis for the prevention and treatment of bipolar disorder.

The latest data from the Global Burden of Disease (GBD) database in 2021 were selected. The Joinpoint regression model, age-period-cohort (APC) model, and bayesian age-period-cohort (BAPC) model were used to analyze and predict indicators such as the age-standardized incidence rate and age-standardized disability-adjusted life year (DALY) rate of bipolar disorder among Chinese adolescents, and the average annual percent change (AAPC) was calculated.

From 1990 to 2021, the overall age-standardized incidence rate (1990:22.92/100 000, 2021:23.17/100 000) showed an upward trend (AAPC=0.03, t=8.20, P < 0.01) and change trend of age-standardized DALY rate (1990:33.61/100 000, 2021:33.76/100 000) was relatively flat (AAPC=0.01, t=0.99, P=0.32). From 1990 to 2021, age-standardized incidence rate and age-standardized DALY rate of girls were higher than boys (χ²=16.38, P < 0.01). The net drift values for the incidence rate and DALY rate of bipolar disorder among Chinese adolescents aged 10-24 years were -0.23% and -0.22%, respectively. The highest incidence rate of bipolar disorder among Chinese adolescents aged 10-24 years was observed in the 15-19 age group, with a rate of 33.14/100 000; the highest DALY risk was in the 20-24 age group, with a rate of 57.26/100 000. The lowest incidence risk and DALY risk RR values for bipolar disorder among Chinese adolescents aged 10-24 years were observed in 2017-2021, with RR values of 0.99 (95%CI=0.97-1.00) and 0.98 (95%CI=0.97-0.99), respectively (P < 0.05). Similarly, the lowest incidence risk and DALY risk RR values for this age group were observed in the 2000-2004 birth cohort, both of which were 0.86 (95%CI=0.84-0.87) (P < 0.05). It was projected that the overall age-standardized incidence rate and age-standardized DALY rate of bipolar disorder among Chinese adolescents aged 10-24 years will continue to increase from 2022 to 2031, reaching 24.10/100 000 and 34.90/100 000, respectively, by 2031.

From 1990 to 2021, both the age-standardized incidence rate and age-standardized DALY rate of bipolar disorder among Chinese adolescents shows an upward trend. Special attention should be given to female adolescents, with a focus on controlling the age-standardized incidence rate of bipolar disorder among 15-19 year-old adolescents and the age-standardized DALY rate among 20-24 year-old ones. Efforts should be enhanced to increase awareness and screening for bipolar disorder among adolescents.

To grasp the distribution characteristics and incidence trend of varicella in Shaanxi Province, so as to provide a reference for scientific and accurate prevention and control strategies.

Data of 161 377 varicella cases in Shaanxi Province from 2016 to 2023 were collected and described from Surveillance Report Management System, a subsystem of National Disease Control and Prevention Information Systems of Chinese Center for Disease Control and Prevention. FlexScan 3.1.2 software was used to determine irregular spatial clustering, and spatial clustering area was detected for each year.

The incidence of varicella in Shaanxi Province showed a seasonal bimodal distribution with peaks from April to July (36.68%) and from October to next January (48.07%). The cases were mainly concentrated in the 3-12 years old group (60.50%), and there was a trend of high incidence age shift within the 0-19 age group from 2021. Most of the cases were students (62.40%) and preschool children (17.78%). The outbreaks mainly occurred in primary schools (76.47%). The regional distribution was mainly concentrated in some areas of southern Shaanxi and Guanzhong. Through spatial analysis, the primary clusters were primarily concentrated in Ankang and Hanzhong cities in southern Shaanxi from 2016 to 2023, and the secondary clusters were mainly found in some areas of Guanzhong (Xi'an, Baoji and Weinan cities).

Prevention and control of varicella should be focused on students and kindergartens aged 3-12 years in southern and Guanzhong areas of Shaanxi Province. Continuous varicella surveillance and vaccination measures should be carried out, and the two-dose vaccination strategy and intensive vaccination of key groups should be actively promoted.