Division of Population Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA.
Int J Epidemiol. 2012 Oct;41(5):1338-53. doi: 10.1093/ije/dys078. Epub 2012 May 26.
Current estimates from objective accelerometer data suggest that American adults are sedentary for ∼7.7 h/day. Historically, sedentary behaviour was conceptualized as one end of the physical activity spectrum but is increasingly being viewed as a behaviour distinct from physical activity.
Prospective studies examining the associations between screen time (watching television, watching videos and using a computer) and sitting time and fatal and non-fatal cardiovascular disease (CVD) were identified. These prospective studies relied on self-reported sedentary behaviour.
The majority of prospective studies of screen time and sitting time has shown that greater sedentary time is associated with an increased risk of fatal and non-fatal CVD. Compared with the lowest levels of sedentary time, risk estimates ranged up to 1.68 for the highest level of sitting time and 2.25 for the highest level of screen time after adjustment for a series of covariates, including measures of physical activity. For six studies of screen time and CVD, the summary hazard ratio per 2-h increase was 1.17 (95% CI: 1.13-1.20). For two studies of sitting time, the summary hazard ratio per 2-h increase was 1.05 (95% CI: 1.01-1.09).
Future prospective studies using more objective measures of sedentary behaviour might prove helpful in quantifying better the risk between sedentary behaviour and CVD morbidity and mortality. This budding science may better shape future guideline development as well as clinical and public health interventions to reduce the amount of sedentary behaviour in modern societies.
目前基于客观加速度计数据的估计表明，美国成年人每天大约有 7.7 小时处于久坐状态。从历史上看，久坐行为被视为身体活动谱的一个极端，但它正越来越被视为一种与身体活动不同的行为。
本研究旨在明确屏幕时间（看电视、看视频和使用电脑）和久坐时间与致命性和非致命性心血管疾病（CVD）之间的关联。这些前瞻性研究依赖于自我报告的久坐行为。
大多数关于屏幕时间和久坐时间的前瞻性研究表明，久坐时间越长，致命性和非致命性 CVD 的风险就越高。与最低水平的久坐时间相比，风险估计值最高的久坐时间和最高的屏幕时间分别高达 1.68 和 2.25，这些风险估计值在调整一系列协变量（包括身体活动测量值）后得出。在六项关于屏幕时间和 CVD 的研究中，每增加 2 小时的风险比为 1.17（95%CI：1.13-1.20）。在两项关于久坐时间的研究中，每增加 2 小时的风险比为 1.05（95%CI：1.01-1.09）。
未来使用更客观的久坐行为测量方法的前瞻性研究可能有助于更好地量化久坐行为与 CVD 发病率和死亡率之间的风险。这一新兴科学可能会更好地为未来指南的制定以及临床和公共卫生干预措施提供指导，以减少现代社会中久坐行为的发生。
