Objective:To develop an R script that can efficiently and accurately filter genome-wide association studies (GWASs) from the GWAS Catalog Website.Methods:The selection principles of GWASs were established based on previous studies. The process of manual filtering in the GWAS Catalog was abstracted as standard algorithms. The R script (gwasfilter.R) was written by two programmers and tested many times.Results:It takes six steps for gwasfilter.R to filter GWASs. There are five main self-defined functions among this R script. GWASs can be filtered based on "whether the GWAS has been replicated" "sample size" "ethnicity of the study population" and other conditions. It takes no more than 1 second for this script to filter GWASs of a single trait.Conclusions:This R script (gwasfilter.R) is user-friendly and provides an efficient and standard process to filter GWASs flexibly. The source code is available at github ( https://github.com/lab319/gwas_filter).

BACKGROUND AND PURPOSE: Both genetic factors and smoking are associated with ischemic stroke (IS) risk. However, little is known about the potential interaction of these factors. We aimed to assess whether smoking and a positive family history interact to increase the risk of IS. METHODS: The nationwide prospective study recruited 210,000 men and 300,000 women in 2004 to 2008 at ages 30 to 79 years. During 9.7 years of follow-up, we documented 16,923 and 20,656 incident IS cases in men and women without major chronic diseases at baseline, respectively. Multivariable Cox regression models were used to examine associations between family history and IS. Likelihood ratio tests were used to test the smoking-family history interactions on IS. RESULTS: About 67.8% (n=135,168) of men ever smoked regularly compared with 2.7% (n=7,775) of women. Among men, a significant interaction between family history and smoking on IS was observed (P for interaction=0.03), with more pronounced association between family history and IS among ever-regular smokers (hazard ratio [HR], 1.21; 95% confidence interval [CI], 1.16 to 1.27) than among never-smokers (HR, 1.11; 95% CI, 1.01 to 1.23). The association between family history and IS among ex-smokers after more than 10 years of cessation (HR, 1.01; 95% CI, 0.85 to 1.20) appeared similar to that among never-smokers. Among women, a similar but not significant interaction between family history and smoking on IS was observed. Ever-regular smokers who had a family history of stroke had the highest risk of IS. CONCLUSIONS: Among Chinese men, the association of family history with IS was accentuated by smoking, and such accentuation tended to be lowered by cessation.
Asian Continental Ancestry Group ; Chronic Disease ; Cohort Studies ; Family Health ; Female ; Follow-Up Studies ; Gene-Environment Interaction ; Humans ; Male ; Prospective Studies ; Smoke ; Smoking ; Stroke ; Tobacco

Epidemiology is a discipline integrating methodology and applied science, whose mission is to prevent and control diseases and promote health. This review introduces the new progress of epidemiology from five aspects: communicable diseases, chronic diseases, systems epidemiology, implementation research and big data of health care. New projects and constantly emerging technologies in the field of infectious diseases are inspiring, while more attention should be paid to the environmental factors of pathogen variation. In the field of chronic diseases, there is an urgent need to study the multimorbidity of the elderly. The role of infectious inducers and human microbiota in the occurrence and development of chronic diseases has been gradually revealed. Systems epidemiology, which is of great significance to achieve precision prevention is a new branch and an important supplement of modern epidemiology. Implementation research, is a bridge connecting basic scientific research and public health practice and will provide evidence to support the effective implementation of the Health China Action Plan. The development of health care big data is based on digital public health, which provides a broad research platform and abundant data resources for epidemiology, and will promote the fundamental transformation of the service and management mode of public health.

Objective:To explore the associations between perceived built environment attributes and adults’ leisure-time physical activity in four cities of China.Methods:Multistage cluster random sampling method was used to select adults aged 25 to 64 in Hangzhou, Suzhou, Chengdu, and Qingdao. Data were collected from June 2017 to July 2018. The perception of the urban built environment was assessed by the neighborhood environment walkability scale-abbreviated (NEWS-A), and the physical activity was assessed by the International Physical Activity Questionnaire. Generalized linear mixed models were used to explore the relationship between the perceived built environment and leisure-time physical activities.Results:A total of 3 789 participants were included in the analysis. After adjusting for potential confounders, better access to public services ( OR=1.34, 95% CI: 1.02-1.75) and higher aesthetic quality ( OR=1.37, 95% CI: 1.09-1.73) were positively associated with the possibility of engaging in leisure-time physical activity in the past week. Similarly, these two attributes were positively associated with leisure-time walking. Higher scores on the perception of street connectivity were positively associated with leisure-time walking [ exp( β)=1.09, 95% CI: 1.00-1.19]. Higher residential density [ exp( β)=1.000 4, 95% CI:1.000 0-1.000 8], better access to physical activity destinations[ exp( β)=1.09, 95% CI: 1.00-1.19], and better aesthetics [ exp( β)=1.11, 95% CI:1.00-1.22] were associated with higher leisure-time physical activity. Similarly, these three attributes were positively associated with the possibility of meeting the WHO recommendations. Conclusion:Changing some urban built environment attributes may increase leisure-time physical activity.

Objective:To evaluate the transitions of frailty status and related factors influencing its worsening in middle-aged and elderly adults.Methods:Data was obtained from the Beijing MJ Health Screening Center. A total of 13 689 participants who attended health checkups at least twice during 2008-2019 and had more than three years' intervals during these two health checkups were included in the study. The frailty index comprising 28 variables was used to measure frailty status. Frailty was defined as frailty index ≥0.25, and prefrailty was defined as frailty index >0.10 and <0.25. Logistic regression analysis was performed to investigate the association of socio-demographic factors and lifestyle characteristics with the worsening of frailty status, stratified by frailty status at the first health checkup.Results:The mean age at the first and last health checkups were (42.3±9.2) and (47.9±9.3) years, respectively. The mean interval during these two health checkups was (5.7±1.9) years. At the first health checkup, the prevalence of frailty and prefrailty were 2.5% and 50.3%, respectively. While at the last health checkup, the prevalence of frailty and prefrailty rose to 3.9% and 55.4%. Of all participants, 67.3% remained in the same frailty state, 21.2% worsening, and 12.5% improving. In robust participants at the first health checkup, older age, female, low education level, smoking cessation, daily smoking, being general obesity measured by BMI or central obesity measured by WHR showed an increased the risk of worsening frailty status. However, in prefrail participants at the first health checkup, older age, female, general, or central obesity presented as risk factors for worsening frailty status.Conclusion:Modifiable factors such as low education level, smoking, and obesity may increase the risk of worsening frailty status.

Objective: To evaluate the association between the frequency of bowel movement (BMF) and the risk of Parkinson’s disease (PD). Methods: In this study, 510 134 participants from the China Kadoorie Biobank (CKB) were included after excluding those who reported to had been diagnosed with cancer at baseline survey. The baseline survey was conducted from 2004 to 2008. The study used the data from the baseline survey and follow-up until December 31, 2016. Cox proportional hazards regression models were used to estimate the HRs and the 95%CIs of risk of PD diagnosis with BMF. Results: During an average follow-up period of (9.9±1.9) years, 808 participants were diagnosed with PD. Compared with participants who had bowel movements every day, the multivariable-adjusted HR (95%CI) for those who had bowel movements<3 times/week, once every 2-3 days, and>1 time/day were 3.62 (2.88-4.54), 2.13 (1.74-2.60), and 0.81 (0.63-1.05), respectively. The linear trend test results of the association between BMF and risk of PD diagnosis was significant (P<0.001). Compared with the participants who had bowel movements ≥1 time/day, the multivariable-adjusted HR (95%CI) for those who had bowel movements<1 time/day was 3.13 (2.32-4.23) within the 5 years of follow- up and was 2.48 (2.05-3.01) beyond the 5 years of follow-up. The gender specific results were similar. The association of BMF<1 time/day with risk of PD diagnosis was stronger in older participants. Conclusions The participants with low BMF at baseline survey would have higher risk for PD diagnosis in the subsequent 10 years on average. Since abnormal decrease of BMF is easy to be found, programs could be set up for the early screening of PD in older people, along with other early symptoms of PD.

Objective: To examine the association between the frequencies of bowel movement (BMF) and the risk of colorectal cancer (CRC). Methods: In this study, 510 134 participants from the China Kadoorie Biobank (CKB) were included, after excluding those who reported as having been diagnosed with cancer at the baseline survey. The baseline survey was conducted from June 2004 to July 2008. The present study included data from baseline and follow-up until December 31, 2016. We used the Cox proportional hazards regression models to estimate the HR and the 95%CI of incident CRC with BMF. Results: During an average follow-up period of 9.9 years, 3 056 participants were documented as having developed colorectal cancer. In the site-specific analysis, 1 548 colon cancer and 1 475 rectal cancer were included. Compared with participants who had bowel movements on the daily base, the multivariable-adjusted HR (95%CI) for those who had more than once of BMF were 1.24 (1.12-1.39) for CRC, 1.12 (0.95-1.31) for colon cancer, and 1.37 (1.18-1.59) for rectal cancer. We further examined the association between BMF and CRC, according to the stages of follow-up, the corresponding HR (95%CI) for CRC, colon and rectal cancer were 1.59 (1.36-1.86), 1.43 (1.14- 1.80), and 1.76 (1.41-2.19) for the first five years, while such associations became statistically insignificant in the subsequent follow-up (P for all interactions were <0.05), as time went on. As for CRC, colon or rectal cancers among participants who had lower bowel movements, the risks were not significantly different from those who had bowel movements everyday. Conclusions Participants who had BMF more than once a day, appeared an increased risk of CRC in the subsequent five years. Since abnormal increase of bowel movements is easily recognizable, programs should be set up on health self- management and early screening for CRC.

BACKGROUND: Several studies have reported that polygenic risk scores (PRSs) can enhance risk prediction of coronary artery disease (CAD) in European populations. However, research on this topic is far from sufficient in non-European countries, including China. We aimed to evaluate the potential of PRS for predicting CAD for primary prevention in the Chinese population. METHODS: Participants with genome-wide genotypic data from the China Kadoorie Biobank were divided into training ( n = 28,490) and testing sets ( n = 72,150). Ten previously developed PRSs were evaluated, and new ones were developed using clumping and thresholding or LDpred method. The PRS showing the strongest association with CAD in the training set was selected to further evaluate its effects on improving the traditional CAD risk-prediction model in the testing set. Genetic risk was computed by summing the product of the weights and allele dosages across genome-wide single-nucleotide polymorphisms. Prediction of the 10-year first CAD events was assessed using hazard ratios (HRs) and measures of model discrimination, calibration, and net reclassification improvement (NRI). Hard CAD (nonfatal I21-I23 and fatal I20-I25) and soft CAD (all fatal or nonfatal I20-I25) were analyzed separately. RESULTS: In the testing set, 1214 hard and 7201 soft CAD cases were documented during a mean follow-up of 11.2 years. The HR per standard deviation of the optimal PRS was 1.26 (95% CI:1.19-1.33) for hard CAD. Based on a traditional CAD risk prediction model containing only non-laboratory-based information, the addition of PRS for hard CAD increased Harrell's C index by 0.001 (-0.001 to 0.003) in women and 0.003 (0.001 to 0.005) in men. Among the different high-risk thresholds ranging from 1% to 10%, the highest categorical NRI was 3.2% (95% CI: 0.4-6.0%) at a high-risk threshold of 10.0% in women. The association of the PRS with soft CAD was much weaker than with hard CAD, leading to minimal or no improvement in the soft CAD model. CONCLUSIONS In this Chinese population sample, the current PRSs minimally changed risk discrimination and offered little improvement in risk stratification for soft CAD. Therefore, this may not be suitable for promoting genetic screening in the general Chinese population to improve CAD risk prediction.
Male ; Humans ; Female ; Coronary Artery Disease/genetics* ; Biological Specimen Banks ; East Asian People ; Risk Assessment/methods* ; Genetic Predisposition to Disease/genetics* ; Risk Factors ; Genome-Wide Association Study