Leisure Time Spent Sitting in Relation to Total Mortality in a Prospective Cohort of US Adults

摘要

The obesity epidemic is attributed in part to reduced physical activity. Evidence supports that reducing time spentnsitting, regardless of activity, may improve the metabolic consequences of obesity. Analyses were conducted inna large prospective study of US adults enrolled by the American Cancer Society to examine leisure time spentnsitting and physical activity in relation to mortality. Time spent sitting and physical activity were queried by questionnairenon 53,440 men and 69,776 women who were disease free at enrollment. The authors identified 11,307ndeaths in men and 7,923 deaths in women during the 14-year follow-up. After adjustment for smoking, body massnindex, and other factors, time spent sitting (u00016 vs. <3 hours/day) was associated with mortality in both womenn(relative risk ?1.34, 95% confidence interval (CI): 1.25, 1.44) and men (relative risk ?1.17, 95% CI: 1.11, 1.24).nRelative risks for sitting (u00016 hours/day) and physical activity (<24.5 metabolic equivalent (MET)-hours/week)ncombined were 1.94 (95% CI: 1.70, 2.20) for women and 1.48 (95% CI: 1.33, 1.65) for men, compared with thosenwith the least time sitting and most activity. Associations were strongest for cardiovascular disease mortality. Thentime spent sitting was independently associated with total mortality, regardless of physical activity level. Publicnhealth messages should include both being physically active and reducing time spent sitting.