Objective: To analyze the characteristics of latent classes of dietary patterns among children and adolescents in Qinghai Province, and their association with overweight and obesity, so as to provide a scientific basis for conducting targeted nutritional interventions and weight management for the local population. Methods: From May to October 2025, a multi stage stratified cluster random sampling method was employed to recruit 1 611 children and adolescents aged 6-17 years from Chengdong District of Xining City and Gonghe County of Hainan Tibetan Autonomous Prefecture in Qinghai Province. Questionnaire survey was conducted using a questionnaire developed by the Chinese Center for Disease Control and Prevention, and physical examination was conducted by using unified measurement standards. Latent class analysis (LCA) was performed on the food intake frequency of the participants. The χ 2 test and Logistic regression analysis were applied to explore the relationship between dietary patterns and overweight/obesity. Results: The detection rates of overweight, obesity, and overall overweight/obesity among the participants were 10.4%, 5.8%, and 16.2%, respectively. Latent class analysis identified three dietary patterns: modern mixed pattern ( n =399, 24.8%), low diversity pattern ( n =476, 29.5%), and traditional dietary pattern ( n =736, 45.7%). The potential category distribution differences of three dietary patterns among children and adolescents with and without overweight or obesity were statistically significant (non overweight and obesity: 22.5%, 29.1%, 48.4%; overweight and obesity: 36.4%, 31.8%, 31.8%) ( χ 2=30.69, P <0.01). Logistic regression showed that, compared with the traditional dietary pattern, the modern mixed pattern was associated with a higher risk of overweight and obesity ( OR =1.68, 95% CI =1.13-2.49); female sex was associated with a lower risk of overweight/obesity compared with male sex ( OR =0.66, 95% CI =0.50-0.86) (both P <0.05). Conclusions A positive association exists between the modern mixed dietary pattern and obesity in children and adolescents. It is recommended to reduce the intake of grains and unhealthy foods among overweight and obese children and adolescents, while increasing the consumption of legumes, fish, and shrimp, in order to cultivate healthy and rational dietary habits.

Objective: To investigate fast food consumption behaviors among 4th and 5th grade primary school students in agricultural and pastoral areas in Qinghai Province, and to provide scientific basis for nutrition education and intervention measures for school age children in agricultural and pastoral areas. Methods: Using multi stage stratified cluster random sampling method, a total of 969 fourth and fifth grade students were selected from 10 primary schools in 4 counties and districts in 3 cities of Haidong City, Hainan Prefecture and Haixi Prefecture from Qinghai Province. Self administered questionnaires were used to investigate the fast food consumption behaviors of participants. Results: The proportions of senior primary school students in agricultural and pastoral areas of Qinghai Province who had consumed western fast food and traditioal fast food in the past week were 45.8% and 75.6%, respectively, with statistically significant differences ( χ 2=290.24, P <0.05). The times of traditional fast food consumption in the past week among boarding students were higher than that of non boarding students( Z =6.44,5.84, P <0.05). The main reasons for senior primary school students in agricultural and pastoral areas of Qinghai Province to choose to consume western fast food were that it was delicious (84.7%), nutritious (62.6%), clean and hygienic (57.4%), and a better environment (57.0%). The top 4 reasons for chousing Chinese fast food were yummy(83.8%),nutritious(82.8%),clean and healthy(67.4%),and good environment(53.5%). Among the surveyed primary school students, 64.7% believed that diet structure of Chinese fast food was reasonable, 43.0% believed that the nutritional value of Chinese fast food was high, and 39.4% believed that the energy content of western fast food was high. Conclusion Fast food consumption is a common dietary behavior of senior primary school students in agricultural and pastoral areas of Qinghai Province. Relevant departments should strengthen the nutrition education related to fast food, promote the dissemination of health knowledge, enable students to develop a good lifestyle and reduce fast food consumption.

Objective: To study the consumption of beverages among senior primary school students in rural and pastoral areas of Qinghai Province, China, in order to provide evidence for the development of nutrition and intervention strategies. Methods: A multi stage stratified cluster random sampling method was employed to select 969 primary school students in grades 4 and 5 from 10 schools in Hainan Autonomous Prefecture, Haixi Autonomous Prefecture and Haidong City. All participants completed a questionnaire survey on daily beverage consumption. The Chi square test was performed to compare differences in reported rates of beverage consumption among students in different groups. Results: The proportion of students who consumed beverages at home, school and elsewhere were 96.9%, 64.5% and 84.9%, respectively. The most popular beverages consumed at home were milk and yogurt ( 63.1 %), tea water (53.0%), and tea drinks (52.4%). The most popular beverages consumed at school were tea(29.8%), milk and yogurt (27.8%) and tea drinks (18.4%), while the most popular beverages consumed in other places were tea drinks ( 42.0 %), carbonated drinks (38.1%) and milk and yogurt (35.0%). The top five reasons for choosing a given beverage were taste delicious (81.2%), nutritious (57.6%),healthy and clean(52.6%),many students like to drink(39.6%),family members often drink(37.7%). Conclusion The consumption of beverages was popular among students, and sugared beverages represented a large proportion of the beverages consumed. Therefore, there is an urgent need to improve the food environment and provide effective nutrition education for students, so as to encourage the consumption of healthy beverages and cultivate healthy eating behaviors.

Objective: To understand the current situation regarding snack food consumption among grade 4 and grade 5 primary school students in agricultural and pastoral areas of Qinghai Province, China, and to provide a scientific basis for nutrition education and intervention strategies. Methods: Multistage stratified cluster random sampling was employed. The research included 969 fourth and fifth grade students were selected from 10 primary schools in four counties and districts of three cities in Haidong City, Hainan Prefecture and Haixi Prefecture in Qinghai Province. The self report questionnaire method was used to investigate the current status regarding snack food consumption in this population. Results: The proportion of students who consumed snack food at home, school and elsewhere were 98.2%, 88.5% and 75.4%, respectively. Male students reported a lower rate of snack consumption at school than female students ( χ 2=9.66). The fifth grade students reported a higher rate of snack consumption at home and other places than the fourth grade students ( χ 2=10.31, 6.77). The reported rate of snack consumption of students in the rural was higher than that in the county( χ 2=6.03,100.53, 24.77). The reported rate of snack consumption of boarding students at home was lower than that of non-boarding students ( χ 2=7.22), while the reported rate of snack consumption at school was higher than that of non-boarding students ( χ 2=9.04）（ P <0.01). The most popular snacks consumed at home included fruits and vegetables, cereals and nuts (76.9%, 67.2%, 63.7%), while the most popular snacks consumed at school were fruits and vegetables, cereals and candies (45.1%, 36.9%, 24.4%). The most popular snacks consumed in other settings included ice cream, candies and beverages(54.7%, 51.6%, 42.9%). The top three reasons for snacking were that snacks were regarded as delicious, healthy/nutritious and clean (76.9%, 65.5% and 59.0%, respectively). Conclusion Snacking is popular among students, although many snacks are unhealthy. Therefore, there is a need to improve food environments and nutrition education, so as to help students to choose healthy beverages and adopt healthy eating behaviors.

Objective: To examine breakfast consumption among primary school students in grades 4 and 5 in Qinghai Province, China, and to provide evidence for nutrition education and intervention strategies. Methods: We used a multistage stratified cluster random sampling method to select the participants. A total of 969 students were selected from 10 primary schools in four counties and districts of three cities, namely Haidong City, Hainan Prefecture and Haixi Prefecture in Qinghai Province. A self rated questionnaire was administered to investigate breakfast consumption. Results: The proportion of students who consumed breakfast 5 to 7 times per week, 3 or 4 times per week, and 1 or 2 times per week were 82.0%, 9.7%, and 6.7%, respectively, while 1.5% never ate breakfast. In descending order, the breakfast food types consumed were cereals and tubers; milk, legumes and nuts; vegetables and fruits; fish and poultry; and meat and eggs (84.1%, 69.8%, 66.8%, and 37.7%, respectively). The proportion of vegetables and fruits in the breakfast of grade 5 students was higher than that of grade 4 students( χ 2=4.81, P = 0.03 ), the proportion of fish, poultry,meat and eggs in county urban areas was higher than that of students in rural( χ 2=6.94, P =0.03), while the proportion of vegetables and fruits in urban areas was lower than that of students in suburban areas( χ 2=53.33, P <0.01). The proportion of breakfast food containing fish,poultry,meat and eggs of boarding students was higher than that of non boarding students( χ 2=41.26, P <0.01), while the proportion of breakfast food containing vegetables and fruits, milk & legumens & nuts was lower than that of non-boarding students( χ 2=21.11, 4.41, P <0.01). A total of 44.8% of students had a poor quality breakfast, and only 16.3% had a good quality breakfast. Moreover, 47.5% of breakfasts were prepared by mothers, followed by the school canteen which prepared 29.9%. Except for students in different grades, there were statistically significant differences in the distribution of breakfast preparers in other groups( P <0.05). Conclusion In Qinghai Province,breakfast skipping is observed in some senior primary school students, and the quality of breakfast is poor. Diet and nutrition education should be provided for students, parents, and school canteen staff to improve the frequency and nutritional quality of children s breakfasts.

Objective: To understand the current situation of food intake frequency among schoolage children in agricultural and pastoral areas of Qinghai Province, and to provide a scientific basis for local education departments and schools to formulate scientific nutrition improvement plans and measures. Methods: A multi stage stratified cluster random sampling method was used to select 969 fourth and fifth grade primary school students from 10 primary schools in Hainan Autonomous Prefecture, Haixi Autonomous Prefecture and Haidong City. All the participants were investigated with a questionnaire survey of dietary behaviors. Results: For the fourth and fifth grade primary school students, the highest proportion of "eaten almost every day" were cereal and tuber ( 84.3 %) and fruits (44.6%), and the highest proportion of "barely eaten" was aquatic product (68.1%) and nutritious supplementary (45.9%). The intake of livestock meat and poultry, fishery products, beverages and nutritional supplements of boys was higher than that of girls（ Z =-2.46，-2.46，-2.43，-2.37， P ＜0.05）. The intake of livestock meat and poultry and snacks of fifth grade students was higher than that of fourth grade students, while the intake of fishery products was lower than that of fourth grade students（ Z = -2.66 ，-4.33，-2.65， P ＜0.05）. Conclusion The frequency of food intake varies among students of differences genders, grades, areas, boarding situation and urbanities. Relevant departments should improve nutrition improvement plans for school age children with different characteristics. Schools and families should carry out nutrition education works to cultivate healthy eating behaviors of students.

The prevention and control of chronic and non-communicable diseases is an important public health problem in China. The general environment in the northwestern China is unique, and the health and disease status of local population is distinctive. In order to meet the urgent need for in-depth research of the causes, mechanisms and prognosis of chronic and non-communicable diseases in this area, a general population cohort in Shaanxi Province, Gansu Province and Qinghai Province, Ningxia Hui Autonomous Region and Xinjiang Uygur Autonomous Region was established during 2017-2019. A total of 117 644 general individuals aged 35-74 years in the multi-ethnic groups (Han, Hui, Uygur, Kazak and Tibetan) were recruited according to the special ecological environment, population size and ethnic distribution. The baseline information about individual exposure, environment and society were collected. More than 900 000 biological samples, including whole blood, plasma, serum and buffy coat, were collected and stored at -80 ℃ in standardized biobank. The long-term observation has started in forms of routine monitoring and active follow-up. The average age of the cohort members was 52.43 years, and 70 391 cohort members were women (59.8%). There were some differences in socio-economic status and lifestyle among different ethnic groups. Although the cohort members in different ethnic groups had similar health status, different characteristics still existed. The cohort can serve as a platform for in-depth research of the relationship between major chronic and non-communicable diseases and environment, people's lifestyle and genetic factors, and the research results can be used as important epidemiological evidence for clarifying the causes of chronic and non-communicable diseases and long-term health hazards in different ethnic groups in this area and reference for the national chronic and non-communicable disease prevention and control. This paper briefly introduces the design and practice of general population cohort in northwestern China.

Objective:To explore the association between short-term exposures to fine particulate matter (PM 2.5) on blood lipids in the elderly. Methods:In this panel study, five repeated measurements were performed on 76 people aged 60-69 in Jinan city. Each participant had a PM 2.5 monitor for 72 hours before each health examination, including a questionnaire survey, physical examination, and biological sample collection. Serum triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were examined, and non-HDL-C concentrations were calculated by subtracting HDL-C from TC. The generalized linear mixed-effects model was used to quantify the association of personal PM 2.5 exposure at different lag with blood lipids and dyslipidemia. Results:The age of 70 participants was (65.0±2.8) years, of which 48.6% (34/70) were males. The BMI of participants was (25.0±2.5) kg/m 2. Their TC, TG, LDL-C, HDL-C, and non-HDL-C concentrations were (5.75±1.32), (1.55±0.53), (3.27±0.94), (1.78±0.52), and (3.97±1.06) mmol/L, respectively. Generalized linear mixed-effects model showed that after adjusting for confounding factors, at lag 72 hours, each 10 μg/m 3 increase in PM 2.5 was associated with the percentage change in TC, LDL-C, HDL-C and non-HDL-C about 1.77% (95% CI: 1.22%-2.32%), 1.90% (95% CI: 1.18%-2.63%), 1.99% (95% CI: 1.37%-2.60%) and 1.74% (95% CI: 1.11%-2.37%), and the OR values (95% CI) of hypercholesterolemia, hypertriglyceridemia and hyperbetalipoproteinemia were 1.11 (1.01-1.22), 1.33 (1.03-1.71) and 1.15 (1.01-1.31), respectively. Conclusion:There is a significant association of short-term PM 2.5 exposure with the concentration of blood lipids and the risk of dyslipidemia in the elderly.

Objective:To explore the association between short-term exposures to fine particulate matter (PM 2.5) on blood lipids in the elderly. Methods:In this panel study, five repeated measurements were performed on 76 people aged 60-69 in Jinan city. Each participant had a PM 2.5 monitor for 72 hours before each health examination, including a questionnaire survey, physical examination, and biological sample collection. Serum triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were examined, and non-HDL-C concentrations were calculated by subtracting HDL-C from TC. The generalized linear mixed-effects model was used to quantify the association of personal PM 2.5 exposure at different lag with blood lipids and dyslipidemia. Results:The age of 70 participants was (65.0±2.8) years, of which 48.6% (34/70) were males. The BMI of participants was (25.0±2.5) kg/m 2. Their TC, TG, LDL-C, HDL-C, and non-HDL-C concentrations were (5.75±1.32), (1.55±0.53), (3.27±0.94), (1.78±0.52), and (3.97±1.06) mmol/L, respectively. Generalized linear mixed-effects model showed that after adjusting for confounding factors, at lag 72 hours, each 10 μg/m 3 increase in PM 2.5 was associated with the percentage change in TC, LDL-C, HDL-C and non-HDL-C about 1.77% (95% CI: 1.22%-2.32%), 1.90% (95% CI: 1.18%-2.63%), 1.99% (95% CI: 1.37%-2.60%) and 1.74% (95% CI: 1.11%-2.37%), and the OR values (95% CI) of hypercholesterolemia, hypertriglyceridemia and hyperbetalipoproteinemia were 1.11 (1.01-1.22), 1.33 (1.03-1.71) and 1.15 (1.01-1.31), respectively. Conclusion:There is a significant association of short-term PM 2.5 exposure with the concentration of blood lipids and the risk of dyslipidemia in the elderly.

Objective:To understand the prevalence of Neisseria gonorrhoeae (NG) infection and related factors in outpatients of sexually transmitted disease (STD) in Shenzhen and provide scientific evidence for targeted intervention. Methods:A cross-sectional study was conducted in STD outpatients who were aged 18-49 years, had had sexual intercourse, had not received antibiotics in the last 2 weeks and sought medical cares in 22 medical institutions in 6 districts of Shenzhen from 15 April, 2018 to 16 May, 2018, their basic information and urine samples were collected, and NG in urine sample was detected by nucleic acid amplification test. Logistic regression analysis was conducted to identify the related factors for NG infection.Results:The information collection and sample collection were completed for 8 324 STD outpatients, among these STD outpatients, 196 were NG positive, with a positive rate of 2.4% (196/8 324). The positive rate of NG in men (5.8%, 148/2 567) was higher than that in women (0.8%, 47/5 742) ( χ2=189.43, P<0.05). Aged 24 years or below ( OR=2.11, 95% CI: 1.44-3.09), single/divorced/widowed ( OR=1.98, 95% CI:1.38-2.84), having casual sex in the last 3 months ( OR=1.77, 95% CI:1.29-2.43) were the related factors for NG infection. Conclusions:We found that NG infection rate was high in STD outpatients in Shenzhen. The infection rates in men and in women differed obviously. It is necessary to conduct gonorrhea screening and intervention in STD outpatients with high-risk behaviors, such as extramarital and casual sex behaviors, and standardize the treatment to reduce the incidence and spread of gonorrhea and other STDs.