Pulsford Richard M, Stamatakis Emmanuel, Britton Annie R, Brunner Eric J, Hillsdon Melvyn
Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK,
Charles Perkins Centre, Sydney, NSW, Australia, Exercise and Sport Sciences, University of Sydney, Sydney, NSW, Australia and Department of Epidemiology and Public Health, University College London, London, UK.
Int J Epidemiol. 2015 Dec;44(6):1909-16. doi: 10.1093/ije/dyv191. Epub 2015 Oct 9.
Sitting behaviours have been linked with increased risk of all-cause mortality independent of moderate to vigorous physical activity (MVPA). Previous studies have tended to examine single indicators of sitting or all sitting behaviours combined. This study aims to enhance the evidence base by examining the type-specific prospective associations of four different sitting behaviours as well as total sitting with the risk of all-cause mortality.
Participants (3720 men and 1412 women) from the Whitehall II cohort study who were free from cardiovascular disease provided information on weekly sitting time (at work, during leisure time, while watching TV, during leisure time excluding TV, and at work and during leisure time combined) and covariates in 1997-99. Cox proportional hazards models were used to investigate prospective associations between sitting time (h/week) and mortality risk. Follow-up was from date of measurement until (the earliest of) death, date of censor or July 31 2014.
Over 81 373 person-years of follow-up (mean follow-up time 15.7 ± 2.2 years) a total of 450 deaths were recorded. No associations were observed between any of the five sitting indicators and mortality risk, either in unadjusted models or models adjusted for covariates including MVPA.
Sitting time was not associated with all-cause mortality risk. The results of this study suggest that policy makers and clinicians should be cautious about placing emphasis on sitting behaviour as a risk factor for mortality that is distinct from the effect of physical activity.
久坐行为与全因死亡率增加有关，且独立于中度至剧烈身体活动（MVPA）。以往的研究往往只考察单一的久坐指标或所有久坐行为的综合情况。本研究旨在通过考察四种不同久坐行为以及总久坐时间与全因死亡率风险的特定类型前瞻性关联，来加强证据基础。
来自白厅II队列研究的参与者（3720名男性和1412名女性），他们没有心血管疾病，在1997 - 1999年提供了每周久坐时间（工作时、休闲时、看电视时、不包括看电视的休闲时以及工作和休闲时合计）和协变量的信息。使用Cox比例风险模型来研究久坐时间（小时/周）与死亡风险之间的前瞻性关联。随访从测量日期开始，直至（最早的）死亡、审查日期或2014年7月31日。
在超过81373人年的随访中（平均随访时间15.7±2.2年），共记录了450例死亡。在未调整的模型或调整了包括MVPA在内的协变量的模型中，未观察到五个久坐指标中的任何一个与死亡风险之间存在关联。
久坐时间与全因死亡率风险无关。本研究结果表明，政策制定者和临床医生在将久坐行为作为与身体活动影响不同的死亡风险因素加以强调时应谨慎。
