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1.
Chinese Journal of Epidemiology ; (12): 48-54, 2020.
Article in Chinese | WPRIM | ID: wpr-798881

ABSTRACT

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.

2.
Chinese Journal of Epidemiology ; (12): 48-54, 2020.
Article in Chinese | WPRIM | ID: wpr-787737

ABSTRACT

@#To evaluate the association between the frequency of bowel movement (BMF) and the risk of Parkinson's disease (PD). 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 s and the 95s of risk of PD diagnosis with BMF. 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 (95) 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 (<0.001). Compared with the participants who had bowel movements ≥1 time/day, the multivariable-adjusted (95) 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. 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.

3.
Chinese Journal of Epidemiology ; (12): 917-923, 2019.
Article in Chinese | WPRIM | ID: wpr-805741

ABSTRACT

Objective@#To describe the characteristics of habitual snoring among adults from 10 regions engaged in the China Kadoorie Biobank (CKB) study.@*Methods@#The baseline survey of CKB was conducted from 2004 to 2008. Data was collected regarding the information on socio- demographic characteristics, lifestyle, sleeping habits, and results from the physical examination of the participants. Logistic regression models were used to compare the regional differences and to estimate the associations of other baseline characteristics on snoring habit.@*Results@#A total of 512 713 participants were included in this study. The overall prevalence of habitual snoring was 21.2%, higher among men, in south regions and urban areas, but no difference observed among people with different socioeconomic status after adjusting for age, regions, BMI, waist circumference or lifestyle factors. Results showed that the prevalence of habitual snoring under the multivariable adjusted model increased among current and ever smokers, also among current and ever alcohol consumers. The risk of habitual snoring was increased by 19% per 1 kg/m2 and 6% per 1 cm increment in BMI or waist circumference, respectively. Among participants with similar BMI, central obese individuals were more likely to be habitual snorers. For individuals with similar waist circumference, the prevalence of habitual snoring was higher among those with higher BMI.@*Conclusion@#The prevalence of habitual snoring varied across regions. Substantial differences in habitual snoring were also seen among people with different lifestyles and body sizes.

4.
Chinese Journal of Epidemiology ; (12): 515-520, 2019.
Article in Chinese | WPRIM | ID: wpr-805195

ABSTRACT

Objective@#To understand the fruit consumption of adults of Qingdao and examine the association between fruit consumption and stroke.@*Methods@#We analyzed baseline data and stroke incidence of the participants who were aged 30-79 years and had been enrolled into the China Kadoorie Biobank (CKB) study from Qingdao city. Cox proportional hazards regression model was conducted to estimate the association of fruit consumption with risk of stroke.@*Results@#A total of 35 509 participants were investgated in the baseline survey. Ratio of male to female was 1∶1.27, and the average age was (50.3±10.2) years. Respondents with higher frequency of fruit consumption were younger, more women, with higher education level and higher income (P<0.05). A total of 1 011 new cases of stroke were observed, with a stroke incidence of 387.63/100 000 person-years. Multivariate Cox regression analysis showed that fruit consumption had a protective effect on stroke incidence. Compared to the respondents who never consumed fruit, respondents who consumed fruit more than 4 days per week had a 44% lower risk of stroke incidence (HR=0.56, 95%CI: 0.50-0.62, P<0.05), and the risk reduced by 46% (HR=0.54, 95%CI: 0.46-0.64, P<0.05) and 42% (HR=0.58, 95%CI: 0.52-0.69, P<0.05) in male and female, respectively. Further adjustment for WC, BMI, SBP and random blood glucose did not change the association.@*Conclusion@#Increasing fruit consumption can effectively decrease the risk of stroke. People should increase fruit consumption advisably to set up reasonable and healthy dietary habits.

5.
Chinese Journal of Epidemiology ; (12): 510-514, 2019.
Article in Chinese | WPRIM | ID: wpr-805194

ABSTRACT

Objective@#To understand the characteristics of adulthood weight change through the analysis on data from China Kadoorie Biobank (CKB) Study of 0.5 million adults from ten areas in China.@*Methods@#An electronic questionnaire was used to collect the information about the body weight at age 25 years, social-demographic characteristics and lifestyle of the study subjects and their body weight were measured. After excluding the adults with self-reported histories of coronary heart disease, stroke, cancer or diabetes and those who had no data of body weight at age 25 years and those aged outside of 35-70 years, a total of 360 903 adults were included in the analysis. Adulthood weight change were defined as difference value between current body weight and body weight at age 25 years.@*Results@#The mean adulthood weight change of the participants was 4.9 kg. The adults living in urban area showed more body weight increase compared with those living in rural area, so did the adults in northern area compared with those in southern area. Among the ten areas in China, Qingdao reported the highest adulthood weight increase (9.3 kg), and Gansu reported the lowest adulthood weight increase (1.5 kg). Older adults had higher BMI at early adulthood (25 years old), but the adults aged 45-50 years had the highest adulthood body weight increase. Adults with higher educational level, higher household income level, but lower physical activity level had more body weight increase, while current smokers, farmers and workers had less body weight increase. BMI at age 25 years was negatively associated with adulthood body weight change, but current BMI was positively associated with adulthood body weight change (P<0.001).@*Conclusion@#Adulthood body weight change varied greatly among population with different demographic characteristics and lifestyle and in ten areas in China.

6.
Chinese Journal of Epidemiology ; (12): 382-388, 2019.
Article in Chinese | WPRIM | ID: wpr-804997

ABSTRACT

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.

7.
Chinese Journal of Epidemiology ; (12): 376-381, 2019.
Article in Chinese | WPRIM | ID: wpr-804996

ABSTRACT

Objective@#To describe the regional and population-related differences in skeletal muscle mass and handgrip strength across the 10 regions of China.@*Methods@#24 533 participants aged 38-88 years from the second resurvey of China Kadoorie Biobank were included in our analyses. Appendicular and trunk skeletal muscle mass were assessed using the bioelectrical impedance analysis (TANITA). Handgrip strength was measured using Jamar hand-held dynamometer. Low muscle mass and low muscle strength were defined as the lowest quintile of height-adjusted appendicular muscle mass or handgrip strength according to the Consensus Report of the Asian Working Group for Sarcopenia. We analyzed the mean value of absolute muscle mass, height-adjusted muscle mass, weight-adjusted muscle mass and handgrip strength. We also reported the prevalence of low muscle mass and low muscle strength.@*Results@#The average appendicular and total skeletal muscle mass were (22.0±0.02) kg and (49.7±0.05) kg in men, which were higher than in women [(15.9±0.02) kg and (37.2±0.04) kg, respectively]. The handgrip strength was (32.6±0.06) kg in men, which was higher than (19.9±0.05) kg in women. The absolute muscle mass was higher in north area and urban region (P<0.001). The weight-adjusted muscle mass showed reverse patterns of regional difference compared with height-adjusted muscle mass. Both muscle mass and handgrip strength decreased by age (trend P<0.001), with a larger decline observed in handgrip strength. According to AWGS criteria, the proportions of low muscle mass and strength increased by age. Among participants over 80 years old, the prevalence of low muscle mass and strength were 56.2% and 74.5% in men, and 35.7% and 66.0% in women.@*Conclusions@#Levels of skeletal muscle mass and strength varied greatly among people from 10 regions and among participants with different demographic characteristics. The prevalence of low muscle mass and strength was extremely high in elderly.

8.
Chinese Journal of Epidemiology ; (12): 1541-1547, 2019.
Article in Chinese | WPRIM | ID: wpr-800268

ABSTRACT

Objective@#To examine the association of BMI with major chronic diseases morbidity and all-cause mortality in Chinese adults.@*Methods@#This study is based on China Kadoorie Biobank. Anthropometric indexes were objectively measured at the baseline survey during 2004-2008. After excluding participants with heart disease, stroke, cancer, COPD and diabetes, 428 113 participants aged 30 to 79 years were included in the analysis. Cox regression models were used to investigate the associations of BMI and waist circumference with incidence of major chronic diseases (including cardiovascular disease, cancer, COPD, and type 2 diabetes) and all-cause mortality.@*Results@#Over an average of 10 years, 131 454 participants developed any one of major chronic diseases. A total of 26 892 all-cause deaths were reported. The risk of major chronic diseases increased with BMI. Compared with normal BMI (18.5-24.0 kg/m2), the HR (95%CI) of overweight (BMI 24.0-28.0 kg/m2) and obesity (BMI≥28.0 kg/m2) were 1.26 (95%CI: 1.24-1.27) and 1.59 (95%CI: 1.57-1.62) respectively. Underweight and obesity were both associated with risk of all-cause mortality. Waist circumference was positively associated with risk of major chronic diseases and all-cause mortality. According to recommended cut-off points of BMI and waist circumference for Chinese adults, maintaining a healthy body weight would prevent 12% incident cases of major chronic diseases.@*Conclusion@#General and central obesity were risk factors for major chronic disease among Chinese adults.

9.
Chinese Journal of Epidemiology ; (12): 1533-1540, 2019.
Article in Chinese | WPRIM | ID: wpr-800267

ABSTRACT

Objective@#To assess the association of BMI and waist circumference (WC) with metabolic risk factors, and confirm the appropriate cut-off points of BMI and WC among Chinese adults.@*Methods@#After excluding participants with missing or extreme measurement values, as well as individuals with self-reported histories of cancer, a total of 501 201 adults in baseline and 19 201 adults in the second re-survey from the China Kadoorie Biobank were included. The associations of BMI and WC with metabolic risk factors were estimated. Receiver operating characteristic (ROC) analyses were conducted to assess the appropriate cut-off values of BMI and WC to predict the risk of hypertension, diabetes, dyslipidemia and clustering of risk factors.@*Results@#The prevalence of hypertension, diabetes, dyslipidemia and clustering of risk factors all presented ascending trends with the increasing levels of BMI or WC. Defined as the points on the ROC curve where Youden’s index reached the highest, the appropriate overweight cut-off points of BMI were around 24.0 kg/m2 both in men and women, and the points of WC were around 85 cm in men and 80 to 85 cm in women. With specificity 90% for identification of risk factors, the appropriate obese cut-off points of BMI were around 28.0 kg/m2 both in men and women, with the range of 27.0 to 28.9 kg/m2.@*Conclusions@#The cut-off points for overweight and obesity recommended by Coorperative Meta-analysis Group of China Obesity Task Force was verified in the large sample survey conducted more recently. The cut-off points of BMI were 24.0 and 28.0 kg/m2 for overweight and obesity, and the cut-off point of WC was 85 cm in men and 80 to 85 cm in women for central obesity.

10.
Chinese Journal of Epidemiology ; (12): 759-764, 2019.
Article in Chinese | WPRIM | ID: wpr-810723

ABSTRACT

Objective@#To evaluate the correlation between alcohol consumption and obesity in adults in China.@*Methods@#The information about alcohol consumption were collected at the baseline survey of the China Kadoorie Biobank. The general obesity and central obesity were defined by BMI and waist circumference (WC) respectively. Logistic regression model was employed to examine the relationship of drinking behavior with general obesity and central obesity.@*Results@#A total of 249 873 adults were included. A J-shaped relationship was observed between alcohol consumption and obesity measurement index (BMI and WC) in men. Compared with non-drinkers, the proportion of general obesity and central obesity were lower in light drinkers (men: OR=0.65, 95%CI: 0.59-0.71 and OR=0.93, 95%CI: 0.88-0.98; women: OR=0.77, 95%CI: 0.65-0.91 and OR=0.89, 95%CI: 0.80-0.99). In men, the proportion of general obesity and central obesity was highest in heavy drinkers (OR=1.21, 95%CI: 1.12-1.32; OR=1.33, 95%CI: 1.27-1.40). BMI and WC were higher in those with a drinking frequency of 3-5 d/week, with largest of proportion of central obesity (men: OR=1.23, 95%CI: 1.16-1.31; women: OR=1.13, 95%CI: 0.99-1.28). The risk for central obesity in men who began drinking every week before 20 years old was 1.24 times higher than non-drinkers (95%CI: 1.16-1.33). Those who drank beer had lower proportion of general obesity (men: OR=0.74, 95%CI: 0.67-0.82; women: OR=0.54, 95%CI: 0.43-0.68).@*Conclusion@#The proportion of obesity was lower in light drinkers but higher in heavy drinkers; and the earlier drinking started, the higher the risk for obesity was.

11.
Chinese Journal of Epidemiology ; (12): 756-758, 2019.
Article in Chinese | WPRIM | ID: wpr-810722

ABSTRACT

Long-term follow-up for end point is an extremely important and arduous task in large population-based cohort studies, which is also the key to the success of large cohort studies. Thus, the fundamental question of the achievements above is how to construct a large population- based cohort in a standardized way. The Chinese Preventive Medicine Association coordinated experienced researchers from Zhejiang Provincial Center for Disease Control and Prevention and other professional institutes to write up the group standard entitled Technical specification of long-term follow-up for end point in large population-based cohort study (T/CPMA 002-2019). The standard is drafted with principles of emphasizing the scientific, normative, applicability, and feasible nature. This group standard recommended the follow-up target population, time, content, methods, quality control, and indicators assessment. The standard aims to guide the large population-based cohorts that have been or intended to be established in China, including national cohorts, regional population cohorts, and special population cohorts, hence, to improve domestic scientific research level and the international influence, and to support decision-making and practice of disease prevention and control.

12.
Chinese Journal of Epidemiology ; (12): 753-755, 2019.
Article in Chinese | WPRIM | ID: wpr-810721

ABSTRACT

Large population-based cohort study is an important resource for population disease prevention and control, the results of which provide scientific basis for individualized treatment and precise prevention, and it is also the key strategic content of precision medicine. The Chinese Preventive Medicine Association coordinated experienced researchers from the Chinese Academy of Medical Sciences and other professional institutes to write up the group standard entitled Technical specification of management for field investigation in large population-based cohort study (T/CPMA 001-2019). Based on the research of large population-based cohort study in China and the principle of scientific, normative, applicable, and feasible, the standard proposed six aspects of management requirements including institutional arrangement, personnel composition, equipment, materials, documents and finance, as well as the basic requirements of the on-site investigation, the requirements of each position and the overall quality control requirements, etc.. The standard aims to guide the large population-based cohorts that have been or intended to be established in China, including national cohorts, regional population cohorts, and special population cohorts, hence to improve scientific research level, accelerate scientific research output and provide localization basis for disease prevention and control in China.

13.
Chinese Journal of Epidemiology ; (12): 142-146, 2019.
Article in Chinese | WPRIM | ID: wpr-738229

ABSTRACT

Objective To study the relationship between the age of menarche and the nearterm/long-term obesity in adult women.Methods We analyzed the baseline data of 30 895 women with complete data on menarche and body measurement that was from the China Kadoorie Biobank (CKB) study from 2004 to 2008.The age of menarche was divided into three groups:≤12,13-16 and ≥ 17 years old.Prematurity was set at age ≤ 12 years.Multivariate logistic regression was used to analyze the effects of menarche age on the near/long-term obesity in female adults.Results The average menarche age of respondent appeared as (15.64 ± 1.92) years old,with prematurity number as 1 421,accounting for 4.6% of the total numbers.Regarding the postponing of dates of birth,the age of menarche in women showed an advancing tendency.Among all the adult women under study,803 developed near-term obesity,with the prevalence as 2.6%,while the number of long-term obesity was 3 738,accounting for 12.1%.Refining factors of age,lifestyle,menopausal status,hypertension and diabetes showed that the menarche age was related to the risks of both short-term and long-term obesity in women and the ORs (95%CI) were 2.45 (1.74-3.45) and 1.99 (1.69-2.34),respectively.There was no multiplicative interaction shown between the menarche age and menopausal status on long-term obesity (P=0.324).Conclusion Premature menarche appeared a risk factor for near-term/long-term obesity in adult females.

14.
Chinese Journal of Epidemiology ; (12): 136-141, 2019.
Article in Chinese | WPRIM | ID: wpr-738228

ABSTRACT

Objective To examine the prevalence of'healthy lifestyle'from data extracted from the China Kadoorie Biobank (CKB) of 0.5 million adults from ten areas across China.Methods After excluding participants with self-reported histories of coronary heart disease,stroke or cancer,a total of 487 198 participants at baseline (2004-2008) and 22 604 participants at second survey (2013-2014),were included for analysis.'Healthy lifestyle'was defined as haing the following characteristics:a) never smoking or having stopped smoking for reasons other than illness;b) alcohol drinking <25 g/day (men)/< 15 g/day (women);c) diet rich in vegetables,fruits,legumes and fish,but low in red meat;d) upper quarter of the physical activity level;e) body mass index of 18.5-23.9 kg/m2 and waist circumstance <85 cm (men)/80 cm (women).We calculated the healthy lifestyle scores (HLS) by counting the number of all the healthy lifestyle factors,with a range from 0 to 6.Results At baseline,prevalence rates of the above five healthy lifestyles (except physical activity) were 70.6%,92.6%,8.7%,52.6% and 59.0%,respectively,with the mean HLS being 3.1± 1.2.Most participants (81.4%) had 2-4 healthy components,while only 0.7% (0.2% in men and 1.0% in women) of all the participants had all six healthy lifestyles.Participants who were women,at younger age,with more schooling and rural residents,were more likely to adhere to the healthy lifestyle.After ten years,the mean HLS showed a slight decrease.Conclusion The prevalence of optimal lifestyles in Chinese adults appeared extremely low.Levels of'healthy lifestyle'varied greatly among those populations with different socio-demographic characteristics across the ten areas in China.

15.
Chinese Journal of Epidemiology ; (12): 26-32, 2019.
Article in Chinese | WPRIM | ID: wpr-738210

ABSTRACT

Objective To evaluate the association of educational level with anthropometric measurements at different adult stages and their long-term changes in adults who participated in the second re-survey of China Kadoorie Biobank (CKB).Methods The present study excluded participants who were aged >65 years,with incomplete or extreme measurement values,or with major chronic diseases at baseline survey or re-survey.The weight at age 25 years was self-reported.Body height,body weight and waist circumference at baseline survey (2004-2008) and re-survey (2013-2014) were analyzed.Results The present study included 3 427 men and 6 320 women.Both body weight and waist circumference (WC) increased with age.From age 25 years to baseline survey (mean age 45.2 ± 6.5),the mean weight change per 5-year was (1.70 ± 2.63) kg for men and (1.27 ± 2.10) kg for women.From baseline survey to re-survey (53.2± 6.5),the mean changes per 5-year for body weight were (1.12±2.61) kg for men and 0.90±2.54) kg for women;and that for WC was (3.20±3.79) cm for men and (3.83 ± 3.85) cm for women.Among women,low educational level was consistently associated with higher body mass index (BMI) and WC at age 25 years,baseline survey and re-survey.Among men,low educational level was associated with higher BMI at age 25 years.At baseline survey and re-survey,the educational level in men was not statistically associated with BMI;but men who completed junior or senior high school showed slight higher WC and increase of WC from baseline survey to re-survey than other male participants.Conclusions Body weight and WC increased with age for both men and women.The associations of educational level with BMI and WC were different between men and women.

16.
Chinese Journal of Epidemiology ; (12): 20-25, 2019.
Article in Chinese | WPRIM | ID: wpr-738209

ABSTRACT

Objective To describe the genetic structure of populations in different areas of China,and explore the effects of different strategies to control the confounding factors of the genetic structure in cohort studies.Methods By using the genome-wide association study (GWAS) on data of 4 500 samples from 10 areas of the China Kadoorie Biobank (CKB),we performed principal components analysis to extract the fast and second principal components of the samples for the component two-dimensional diagram generation,and then compared them with the source of sample area to analyze the characteristics of genetic structure of the samples from different areas of China.Based on the CKB cohort data,a simulation data set with cluster sample characteristics such as genetic structure differences and extensive kinship was generated;and the effects of different analysis strategies including traditional analysis scheme and mixed linear model on the inflation factor (λ) were evaluated.Results There were significant genetic structure differences in different areas of China.Distribution of the principal components of the population genetic structure was basically consistent with the geographical distribution of the project area.The first principal component corresponds to the latitude of different areas,and the second principal component corresponds to the longitude of different areas.The generated simulation data showed high false positive rate (λ =1.16),even if the principal components of the genetic structure was adjusted or the area specific subgroup analysis was performed,λ could not be effectively controlled (λ > 1.05);while,by using a mixed linear model adjusting for the kinship matrix,λ was effectively controlled regardless of whether the genetic structure principal component was further adjusted (λ =0.99).Conclusions There were large differences in genetic structure among populations in different areas of China.In molecular epidemiology studies,bias caused by population genetic structure needs to be carefully treated.For large cohort data with complex genetic structure and extensive kinship,it is necessary to use a mixed linear model for association analysis.

17.
Chinese Journal of Epidemiology ; (12): 17-19, 2019.
Article in Chinese | WPRIM | ID: wpr-738208

ABSTRACT

Precision medicine became the key strategy in development priority of science and technology in China.The large population-based cohorts become valuable resources in preventing and treating major diseases in the population,which can contribute scientific evidence for personalized treatment and precise prevention.The fundamental question of the achievements above,therefore,is how to construct a large population-based cohort in a standardized way.The Chinese Preventive Medicine Association co-ordinated experienced researchers from Peking University and other well-known institutes to write up two group standards Technical specification of data processing for large population-based cohort study (T/CPMA 001-2018) and Technical specification of data security for large population-based cohort study (T/CPMA 002-2018),on data management.The standards are drafted with principles of emphasizing their scientific,normative,feasible,and generalizable nature.In these two standards,the key principles are proposed,and technical specifications are recommended in data standardization,cleansing,quality control,data integration,data privacy protection,and database security and stability management in large cohort studies.The standards aim to guide the large population-based cohorts that have been or intended to be established in China,including national cohorts,regional population cohorts,and special population cohorts,hence,to improve domestic scientific research level and the international influence,and to support decision-making and practice of disease prevention and control.

18.
Chinese Journal of Epidemiology ; (12): 142-146, 2019.
Article in Chinese | WPRIM | ID: wpr-736761

ABSTRACT

Objective To study the relationship between the age of menarche and the nearterm/long-term obesity in adult women.Methods We analyzed the baseline data of 30 895 women with complete data on menarche and body measurement that was from the China Kadoorie Biobank (CKB) study from 2004 to 2008.The age of menarche was divided into three groups:≤12,13-16 and ≥ 17 years old.Prematurity was set at age ≤ 12 years.Multivariate logistic regression was used to analyze the effects of menarche age on the near/long-term obesity in female adults.Results The average menarche age of respondent appeared as (15.64 ± 1.92) years old,with prematurity number as 1 421,accounting for 4.6% of the total numbers.Regarding the postponing of dates of birth,the age of menarche in women showed an advancing tendency.Among all the adult women under study,803 developed near-term obesity,with the prevalence as 2.6%,while the number of long-term obesity was 3 738,accounting for 12.1%.Refining factors of age,lifestyle,menopausal status,hypertension and diabetes showed that the menarche age was related to the risks of both short-term and long-term obesity in women and the ORs (95%CI) were 2.45 (1.74-3.45) and 1.99 (1.69-2.34),respectively.There was no multiplicative interaction shown between the menarche age and menopausal status on long-term obesity (P=0.324).Conclusion Premature menarche appeared a risk factor for near-term/long-term obesity in adult females.

19.
Chinese Journal of Epidemiology ; (12): 136-141, 2019.
Article in Chinese | WPRIM | ID: wpr-736760

ABSTRACT

Objective To examine the prevalence of'healthy lifestyle'from data extracted from the China Kadoorie Biobank (CKB) of 0.5 million adults from ten areas across China.Methods After excluding participants with self-reported histories of coronary heart disease,stroke or cancer,a total of 487 198 participants at baseline (2004-2008) and 22 604 participants at second survey (2013-2014),were included for analysis.'Healthy lifestyle'was defined as haing the following characteristics:a) never smoking or having stopped smoking for reasons other than illness;b) alcohol drinking <25 g/day (men)/< 15 g/day (women);c) diet rich in vegetables,fruits,legumes and fish,but low in red meat;d) upper quarter of the physical activity level;e) body mass index of 18.5-23.9 kg/m2 and waist circumstance <85 cm (men)/80 cm (women).We calculated the healthy lifestyle scores (HLS) by counting the number of all the healthy lifestyle factors,with a range from 0 to 6.Results At baseline,prevalence rates of the above five healthy lifestyles (except physical activity) were 70.6%,92.6%,8.7%,52.6% and 59.0%,respectively,with the mean HLS being 3.1± 1.2.Most participants (81.4%) had 2-4 healthy components,while only 0.7% (0.2% in men and 1.0% in women) of all the participants had all six healthy lifestyles.Participants who were women,at younger age,with more schooling and rural residents,were more likely to adhere to the healthy lifestyle.After ten years,the mean HLS showed a slight decrease.Conclusion The prevalence of optimal lifestyles in Chinese adults appeared extremely low.Levels of'healthy lifestyle'varied greatly among those populations with different socio-demographic characteristics across the ten areas in China.

20.
Chinese Journal of Epidemiology ; (12): 26-32, 2019.
Article in Chinese | WPRIM | ID: wpr-736742

ABSTRACT

Objective To evaluate the association of educational level with anthropometric measurements at different adult stages and their long-term changes in adults who participated in the second re-survey of China Kadoorie Biobank (CKB).Methods The present study excluded participants who were aged >65 years,with incomplete or extreme measurement values,or with major chronic diseases at baseline survey or re-survey.The weight at age 25 years was self-reported.Body height,body weight and waist circumference at baseline survey (2004-2008) and re-survey (2013-2014) were analyzed.Results The present study included 3 427 men and 6 320 women.Both body weight and waist circumference (WC) increased with age.From age 25 years to baseline survey (mean age 45.2 ± 6.5),the mean weight change per 5-year was (1.70 ± 2.63) kg for men and (1.27 ± 2.10) kg for women.From baseline survey to re-survey (53.2± 6.5),the mean changes per 5-year for body weight were (1.12±2.61) kg for men and 0.90±2.54) kg for women;and that for WC was (3.20±3.79) cm for men and (3.83 ± 3.85) cm for women.Among women,low educational level was consistently associated with higher body mass index (BMI) and WC at age 25 years,baseline survey and re-survey.Among men,low educational level was associated with higher BMI at age 25 years.At baseline survey and re-survey,the educational level in men was not statistically associated with BMI;but men who completed junior or senior high school showed slight higher WC and increase of WC from baseline survey to re-survey than other male participants.Conclusions Body weight and WC increased with age for both men and women.The associations of educational level with BMI and WC were different between men and women.

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