Abstract P429: Parallel Processes of Sedentary Behavior and Cardiometabolic Risk Factors in Obese Adolescents
Introduction: Sedentary time has been negatively associated with cardiometabolic health in adults. These associations are less clear in youth, may differ by sedentary measurement method, and rarely have been investigated longitudinally.
Hypothesis: Greater accelerometer measured sedentary time and reported screen time will be associated with poorer status on cardiometabolic risk factors at baseline and longitudinally.
Methods: Obese (BMI ≥ 95th percentile for age and gender) 11-13 year olds were enrolled in a primary care weight loss trial. Half were girls and 82% were Hispanic. Of the 106 participants enrolled, 73 completed baseline and 12-month assessments. Assessments occurred in the clinic and included a fasting blood draw. Table 1 lists the risk factor variables.
The first dependent variable was reported screen time (television and computer/video games). The second was total sedentary time, calculated from waist-worn Actigraph accelerometers as percent of wear time with counts < 100 per 60-second epoch.
Mplus software was used to fit latent growth parallel processes models, with the intercept of the biomarker regressed on the sedentary time intercept (cross-sectional association), and the slope of the biomarker regressed on the sedentary time slope (longitudinal association). Models were adjusted for potential confounders. Full information maximum likelihood estimation was used to account for missing data.
Results: Participants reported 3.2 (SD = 2.0) screen time hours. Associations between screen time and risk factors are presented in Table 1.
Total sedentary time (M = 61±11% of wear time) was positively associated with BMI (β = .22; p < .05) at baseline but not with other risk factors. Total sedentary time was not associated with risk factors longitudinally.
Conclusion: Changes in screen time but not total sedentary time were associated with cardiometabolic risk factors, specifically BMI, blood glucose, LDL, AST, and ALT. Associations were independent of physical activity and psychosocial diet variables.
Author Disclosures: J. Carlson: None. G. Norman: None. J. Kolodziejczyk: None. K. Patrick: None.
- © 2014 by American Heart Association, Inc.