Substituting time spent in physical activity and sedentary time and its association with cardiovascular disease among northwest Chinese adults

Objectives: To examine the association between physical activity (PA) and leisure-time sedentary time and cardiovascular disease (CVD). Methods: This cross-sectional study used baseline data from the Regional Ethnic Cohort Study in Northwest China from June 2018 to May 2019. PA and leisure-time sedentary time were self-reported. Logistic regression models analyzed the association of PA and leisure-time sedentary time with CVD prevalence individually and jointly. Restricted cubic spline analyses assessed dose-response relationships. Isotemporal substitution models were used to investigate substituting leisure-time sedentary time, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) with CVD prevalence. Results: The prevalence of CVD was 31.8 %. Compared to the lowest quartile, participants in the highest quartile of total PA had a 32 % lower CVD prevalence (odds ratio [OR]: 0.68, 95 % confidence interval [CI]: 0.62–0.74; P for trend <0.001). The fully adjusted OR for the highest quartile of leisure-time sedentary time compared to the lowest quartile was 1.09 (1.01–1.18; P for trend =0.04). An L-shaped dose-response relationship was observed between PA and CVD prevalence. An active lifestyle and reduced daily leisure-time sedentary time were associated with a 26 % (0.74 [0.63–0.86]) lower CVD prevalence. Additionally, substituting 30 min/day of leisure-time sedentary time with equivalent MVPA was associated with a 2 % (0.98 [0.97–0.99]) reduction in CVD prevalence. Substituting sedentary time with LPA was associated with a lower CVD prevalence in females. Conclusions: An active lifestyle was associated with a lower prevalence of CVD in regional populations, suggesting a feasible strategy for CVD prevention and regional health promotion.