[Objective] To understand the characteristics of dietary diversity of urban families in Ningbo city and analyze the related factors of dietary diversity level. [Methods] The project was carried out based on the baseline survey project of the primary health comprehensive experimental area of the National Health Commission in 2021. Multi-stage stratified cluster random sampling was adopted and household face-to-face inquiry was conducted. The survey questionnaire was divided into four parts: basic information, dietary knowledge and attitudes, dietary consumption frequency, and 24-hour dietary intake. The generalized estimating equation was used to analyze the influencing factors of dietary diversity score. [Results] A total of 632 people were surveyed. Among the nine groups of food (except cooking oils), foods consumed weekly in frequency from high to low were cereals, vegetables, fruits, fish, meat, eggs, beans, and dairy. The overall dietary diversity score (DDS) was 5.78±1.693. Among the surveyed, 9% had insufficient DDS, 62.2% had moderate DDS, and 28.8% had adequate DDS. Age, dietary knowledge acquisition attitude behavior, and family role were significantly correlated with DDS. DDS was 0.70 higher in the group under 40 years old than in the group over 60 years old (P<0.05), and DDS in the group between 40 and 59 years old was 0.46 higher than that in the group over 60 years old (P<0.05). DDS in the occasionally or never actively collected group was 0.93 lower than that in the frequently actively collected group (P<0.001). Among the family role factors, DDS of ordinary family members was 0.32 higher than that of family opinion leader (P<0.05). [Conclusion] The dietary patterns in this region have the characteristics of plant-based and coastal characteristic dietary ones. The intake level of fruits and fish is relatively good, while the intake of legumes and dairy is relatively low, which needs attention.

【Objective】 To estimate the prevalence, associated factors and patterns of multimorbidity of non-communicable diseases among adults in Shaanxi Province so as to provide evidence for the prevention and control of non-communicable diseases. 【Methods】 We used the data of adults aged 18 years and older collected in the baseline survey of Shaanxi Project in the Regional Ethnic Cohort Study in Northwest China. Multinomial logistic regression was used to explore the associated factors for multimorbidity. Exploratory factor analysis was used to extract patterns of multimorbidity. 【Results】 The prevalence of multimorbidity was 10.7% among the 44 442 participants. Age increase, being males, urban residence, and being overweight or obesity were positively associated with multimorbidity. Compared with women, men had a higher risk of multimorbidity. The OR and 95% CI was 1.25 (1.12-1.39). The risk of multimorbidity increased with age among adults. Compared with participants aged 18.0-34.9 years, the ORs and 95% CIs of those aged 35.0-44.9, 45.0-54.9, 55.0-64.9, and ≥65.0 years were 4.73 (3.47-6.46), 15.61 (11.60-21.00), 41.39 (30.76-55.70) and 90.04 (66.58-121.77), respectively. The primary multimorbidity patterns among adults in Shaanxi were cardiovascular-metabolic multimorbidity (5.4%), viscero-articular multimorbidity (1.0%), and respiratory multimorbidity (0.3%). 【Conclusion】 More than one in ten adults in Shaanxi Province had multimorbidity, and the predominant pattern of multimorbidity was cardiovascular-metabolic multimorbidity. The prevention and control of non-communicable diseases should be reinforced in middle-aged and older people, males, people living in the urban, and overweight or obese people. More attention should be paid to the prevention and control of cardiovascular-metabolic diseases.

【Objective】 To evaluate the dietary quality with the dietary balance index (DBI_16) and the association between dietary quality and bone mass among middle-aged and elderly people in Gansu Province so as to provide evidence for improving dietary quality and bone health status of Gansu population. 【Methods】 Based on the information of the type and quantity of food intake and the bone mass of middle-aged and elderly people aged 35 years and above collected by the Gansu Project in the Regional Ethnic Cohort Study in Northwest China, DBI_16 was used to evaluate the intake level of cereals, vegetables, fruits, milk, beans, fish and shrimp, eggs and other foods, and the degree of inadequate, excessive and unbalanced dietary intake of the participants. Multiple linear regression was used to evaluate the associations of three component indexes of DBI_16, high bound score (DBI_HBS), low bound score (DBI_LBS), diet quality distance (DBI_DQD), and seven single indexes of DBI_16 with bone mass. 【Results】 Analyses of the dietary and bone mass data of 11,840 participants showed that 44.8% of participants consumed excessive amounts of cereals compared to the dietary recommendation. 96.3%, 90.6%, 90.1%, 71.9%, 95.1% and 60.3% of participants’ intake of vegetables, fruits, milk, soybeans, fish and shrimp, and eggs, respectively, were inadequate. 47.7% participants consumed less than 10 types of food. 2.3% participants’ DBI_LBS levels were appropriate. 54.7% participants’ DBI_HBS levels were appropriate. Only 1.2% participants’ DBI_DQD reached a balanced level. The bone mass level in the study population was (2.5±0.6) kg [(2.8±0.5) kg for men and (2.3±0.5) kg for women]. After adjusting for sociodemographic characteristics, lifestyle, total dietary energy intake and body mass index, DBI_LBS and DBI_DQD were negatively associated with bone mass [β and 95% CI was -0.002 01 (-0.003 62--0.000 40) and -0.001 76 (-0.003 09--0.000 43), respectively]. 【Conclusion】 Dietary intake imbalance is common among middle-aged and elderly people in Gansu Province, and the more severe the dietary intake imbalance, the lower the bone mass level.

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 investigate the relationship between triglyceride glucose index (TyG) and body inflammation.Methods:The data were obtained from a baseline survey in population in Xi'an in natural population cohort study in northwest China established in 2018-2019. Based on TG and FPG, TyG/TyG-BMI was constructed to reflect insulin resistance (IR) in the body, and systemic immune-inflammation index (SII) reflecting inflammation in the body was constructed using neutrophil, lymphocyte, and platelet counts. A logistic regression model was used to explore the relationship between the TyG and the SII.Results:A total of 11 491 subjects were included in the analysis. After adjusting for covariates, each unit increase in the TyG increased the risk of high SII by 21% ( OR=1.21, 95% CI:1.12-1.30). The risk of high SII in the group with the TyG in Q4 was 1.34 times higher than that in the group Q1 ( OR=1.34, 95% CI:1.18-1.52). Both sensitivity analysis and subgroup analysis further confirmed the stability of the association between the TyG and the SII. In the population with a BMI ranging from 18.5 to 23.9 kg/m 2, for every unit increase in the TyG as a continuous variable, the risk for high SII increased by 31% ( OR=1.31, 95% CI:1.18-1.45). As a categorical variable, the risk for high SII in the Q4 group was 1.52 times higher than that in the Q1 group ( OR=1.52, 95% CI:1.27-1.83). In a population with BMIs ranging from 24.0 to 27.9 kg/m 2, for every unit increase in the TyG as a continuous variable, the risk for high SII increased by 20% ( OR=1.20, 95% CI:1.07-1.35), and there was no significant difference when it was a categorical variable. Conclusions:The increase in IR is closely related to the development of inflammation in the body, and BMI may regulate their relationship. Early prevention of elevated IR levels before overweight or obesity may have a positive effect on the control of inflammation in the body.

Cohort study is one of the important research methods in analytical epidemiology because of its clear time sequence relationship, which is better than other observational studies in demonstrating causal association. However, screening diagnosis or other methods are often used to exclude the individuals with outcome events during the enrollment process of the subjects in cohort studies. The accuracy of screening diagnosis and the effectiveness of exclusion will affect the accuracy of the baseline status assessment of the subjects included in the study, which may lead to the causal time sequence reversal of exposure-outcome in the estimation of causal effect. Landmark analysis can be used to control reverse causality by excluding subjects with potentially unknown expose-outcome timing. In this paper, we describe the basic principles and analytical steps of landmark analysis, and use data from the Chinese Longitudinal Healthy Longevity Survey to explore the relationship between physical activity and frailty, and introduce the specific application of landmark analysis for the purpose of facilitating its application and inferring causal effects more accurately in cohort studies.

With completing a baseline survey of a large natural population cohort, conducting regular follow-up has become a key factor in further improving the quality of cohort construction and ensuring its sustainable development. Typical cohort follow-up methods include repeat surveys, routine monitoring, and community-oriented surveillance. However, in practical applications, there are often issues such as high costs, difficulty, and high error rates. Telephone follow-up is an important supplementary method to the methods mentioned above, as it has the characteristics of low cost, fast response, and high quality. However, the with difficult organization, quality control is challenging, response rates are low, and management levels vary widely, which limits its widespread use in large-scale population cohort studies. Given the above problems, this study draws on customer relationship management based on the actual needs of the China Northwest Cohort follow-up. It relies on the REDCap electronic data collection platform to build a telephone follow-up management and quality control system. Targeted solutions are provided for key issues in telephone follow-up implementation, including organizational structure, project management, data collection, and process quality control, to improve the quality control level of telephone follow-up comprehensively and thereby enhance the quality and efficiency of follow-up. We hope to provide standardized follow-up programs and efficient quality control tools for newly established and existing cohort studies.

【Objective】 To evaluate the diet quality of pregnant women in Shaanxi Province by Diet Balance Index for Pregnancy (DBI_P) and investigate the influencing factors. 【Methods】 By using a multi-stage stratified random sampling method, 7375 pregnant women in 30 districts (counties) of Shaanxi Province were recruited. A structured questionnaire was adopted to collect general information in pregnancy, and a semi-quantitative food frequency questionnaire was used to obtain dietary information in pregnancy. DBI_ P was used to evaluate the diet quality during pregnancy, and the factors influencing diet quality were assessed by multiple linear regression. 【Results】 More than 50% pregnant women had inadequate intakes of dairy products, fish and shrimp, meat and poultry, vegetables, eggs, fruits and diet variety. More than 69% pregnant women had excessive intakes of cooking oil, cereals and salt. The average values of high bound score, low bound score, and diet quality distance were 12.9, 19.5, and 32.5, respectively. The proportions of medium inadequate, excessive, and imbalance of dietary intakes were 20.3%, 22.55%, and 40.8%, respectively. DBI_LBS during pregnancy was negatively correlated with childbearing age, education level, family per capita annual income, antenatal examination frequency and folic acid supplementation, but positively correlated with living in southern and northern Shaanxi, residing in rural areas, being farmers, and drinking alcohol. DBI_HBS during pregnancy was negatively correlated with living in southern and northern Shaanxi, but positively correlated with active/passive smoking and drinking strong tea. DBI_DQD during pregnancy was negatively correlated with education level, family per capita annual income, antenatal examination frequency and folic acid supplementation, but positively correlated with living in southern Shaanxi, residing in rural areas, being farmers, parity, active/passive smoking, and drinking strong tea and coffee. 【Conclusion】 The dietary intake of pregnant women in Shaanxi Province was insufficient and unbalanced, and the dietary quality was affected by sociodemographic and life behavior factors during pregnancy. Nutritional intervention measures should be targeted.

【Objective】 To compare the ability of body mass index （BMI）， body fat percentage （BFP）， waist circumference （WC）， waist-to-height ratio （WHtR）， visceral fat index （VFI） and the combinations of two kinds of obesity indices to predict the risk of hypertension. 【Methods】 Data collected in the baseline survey of “Gansu Province’s Urban and Rural Natural Population Cohort Establishment and Tumor Follow-up Study” were analyzed. Area under the curve （AUC） of ROC curve with covariates was used to analyze and compare the effects of individual obesity evaluation index and the combination of two kinds of obesity indices in predicting the risk of hypertension. 【Results】 Analyses of data of 20，079 adults showed that the AUC of BMI， WC， WHtR， BFP and VFI was 0.636， 0.604， 0.615， 0.614 and 0.619， respectively. AUC of the combination of BMI and WC （0.643） was higher than that of BMI （0.636）； however， the change rate of AUC was only 1.09%. AUC of the combinations of WC， WHtR and VFI， the three central obesity evaluation indices， and BFP， a general obesity evaluation index， were lower than that of BMI. The optimal cutoff value for BMI was 24.2 kg/m². 【Conclusion】 The effect of BMI in predicting the risk of hypertension is better than that of BFP， WC， WHtR and VFI. The effects of the combinations of the two kinds of obesity evaluation indices are not better than that of BMI. To prevent and control hypertension， adults should keep their BMI under overweight.

Objective:To study the relationship between the Chinese dietary guidelines compliance index for pregnant women (CDGCI_PW) and congenital heart disease (CHD) in offspring.Methods:In a hospital-based case-control study conducted in Xi'an, Shaanxi province, semi-quantitative food frequency questionnaires were used to investigate the diets of pregnant women throughout pregnancy. The modified CDGCI_PW score was used to evaluate dietary quality during pregnancy, logistic regression was applied to analyze the relationship between CDGCI_PW score and offspring CHD, and the ROC curve was adopted to construct the prediction model of CDGCI_PW for offspring CHD.Results:A total of 1 422 subjects were enrolled, including 474 in the case group and 948 in the control group. The CDGCI_PW score in the case group M ( Q1, Q3) was 46.0 (26.0, 65.0) lower than that in the control group, which was 60.0 (40.0, 77.0). The difference between the two groups was significant ( P<0.001). Compared with those in the Q1 of CDGCI_PW, the offspring in the Q2, Q3, and Q4 of CDGCI_PW had a lower risk of total CHD ( OR=0.60, 95% CI: 0.43-0.83; OR=0.64, 95% CI: 0.45-0.89; OR=0.29, 95% CI: 0.19-0.44), with the trend test P<0.001. The risk of total CHD was reduced by 17% ( OR=0.83, 95% CI: 0.79-0.88) when 10 points increased the CDGCI_PW score. The area under curve predicted by constructing the ROC curve was 0.793 (95% CI: 0.768-0.818), and at the maximum of the Youden index, the sensitivity was 0.740, and the specificity was 0.725. Conclusion:This study suggests that improving dietary quality during pregnancy may reduce the risk of CHD in offspring.