Relationship Between Daily Sedentary Behaviors and Metabolic Syndrome in Middle-Aged Adults: Results from a Health Survey in Taean-Gun, Republic of Korea

Background: It is unclear whether sedentary behavior is associated with metabolic risk, being independent of physical activity and other possible confounders. This study aimed to evaluate an association between sedentary behaviors and metabolic syndrome (MetS). Methods: A community-based cross-sectional study was conducted in a total of 987 Korean adults aged 40 years or older. Information on study variables, including physical activity, awake and sitting time, and components of MetS, was collected by a self-administered questionnaire, physical measurement, and laboratory test. MetS was defined according to the modified National Cholesterol Education Program's Adult Treatment Panel III and Korean Society for the Study of Obesity. Multiple logistic regression analysis was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for MetS associated with absolute sitting time, high sedentary ratio (>0.5), and other selected covariates, including age, sex, smoking, alcohol intake, educational attainment, daily meal times, regular exercise, intensity of physical activities, and sleep and nap duration. Results: After considering other selected variables, the risk of MetS was found to be higher by about 54% among subjects who had a higher sedentary ratio (OR: 1.54, 95% CI: 1.04-2.28). Every hour increase in sitting time was associated with increased risk of MetS (OR: 1.05, 95% CI: 0.99-1.11) with borderline significance (P = 0.119). Conclusions: Sedentary behavior was independently associated with an increased risk of MetS, suggesting that efforts to reduce the sedentary time might be also important for metabolic health in addition to encouraging adequate physical exercise. Clinical trial number is not applicable to this study.