Waist Circumference of the Elderly over 65 Years Old in China Increased Gradually from 1993 to 2015: A Cohort Study / 生物医学与环境科学（英文）

Objective@#This study aimed to analyze the temporal trends and characteristics associated with waist circumference (WC) among elderly Chinese people.@*Methods@#We used data from 3,096 adults ≥ 65 years who participated in the China Health and Nutrition Survey (CHNS), an ongoing cohort study, between 1993 and 2015. We used longitudinal quantile regression models to explore the temporal trends and characteristics associated with WC.@*Results@#WC increased gradually among the elderly Chinese population during the survey. The WC curves shifted to the right with wider distributions and lower peaks in men and women. All WC percentile curves shifted upward with similar growth rates in the 25th, 50th, and 75th percentiles. The WC means increased from 78 cm to 86 cm during the 22 years of our study. WC significantly increased with age and body mass index and decreased with physical activity (PA). These associations were stronger in the higher percentiles than in the lower percentiles.@*Conclusions@#WC is rising among Chinese adults ≥ 65 years. Factors affecting WC in elderly people may have different effects on different percentiles of the WC distribution, and PA was the most important protective factor in the higher percentiles of the WC distribution. Thus, different interventional strategies are needed.

Associations of Sedentary Time and Physical Activity with Metabolic Syndrome among Chinese Adults: Results from the China Health and Nutrition Survey / 生物医学与环境科学（英文）

Objective@#This study aimed to determine the independent and joint associations of sedentary time (ST) and physical activity (PA) with metabolic syndrome (MetS) and its components among Chinese adults.@*Methods@#The study analyzed data from 4,865 adults aged ≥ 18 years who participated in the 2009 and 2015 China Health and Nutrition Surveys (CHNS). Four types of leisure ST and three types of PA self-reported at baseline were collected. Multivariable logistic regressions were used to determine the independent and joint associations of ST and PA with the odds of MetS or its components.@*Results@#For independent effects, higher levels of television time and total leisure ST was associated with higher MetS risk [odds ratio ( @*Conclusions@#MVPA and total PA have independent preventive effects, and sedentary behavior (mainly watching TV) has an unsafe effect on MetS and its components. Strengthening the participation of MVPA and combining the LPA to replace the TV-based ST to increase the total PA may be necessary to reduce the prevalence of MetS in Chinese adults.