挪威体育学院运动医学系Ulf Ekelund团队，近日分析了加速度计测量的体力活动和久坐时间与全因死亡率之间的剂量-反应关系。2019年8月22日，《英国医学杂志》在线发表了这项成果。

缺乏体力活动与许多慢性病、过早死亡和巨大经济负担有关。越来越多的证据也表明，久坐不动可能会增加患慢性病和死亡的风险。

该研究组从各大数据库中检索相关文献，对加速度计测量的总体力活动、不同强度的体力活动、久坐时间和全因死亡率之间的剂量-反应关系进行系统回顾和荟萃分析。

这项荟萃分析包括36383名参与者，平均年龄62.6岁，72.8%为女性，平均随访5.8年后，2149例（5.9%）死亡。只要从事体力活动，无论强度如何，均会降低死亡率，且剂量-反应呈非线性，第一季度死亡率的风险比为1.00，第二季度为0.48，第三季度为0.34，第四季度为0.27。轻体力活动四个季度死亡率的风险比依次为1.00、0.60、0.44和0.38；中度或剧烈体力活动依次为1.00、0.64、0.55和0.52；久坐不动依次为1.00、1.28、1.71和2.63。

研究人员总结，无论强度如何，总体力活动水平越高，久坐时间越短，早死的风险就越低。

附：英文原文

Title: Dose-response associations between accelerometry measured physical activity and sedentary time and all cause mortality: systematic review and harmonised meta-analysis

Author: Ulf Ekelund, professor, Jakob Tarp, postdoctoral student, Jostein Steene-Johannessen, associate professor, Bjørge H Hansen, associate professor, Barbara Jefferis, senior lecturer, Morten W Fagerland, statistician, Peter Whincup, professor, Keith M Diaz, assistant professor, Steven P Hooker, professor, Ariel Chernofsky, doctoral student, Martin G Larson, professor, Nicole Spartano, assistant professor, Ramachandran S Vasan, professor, Ing-Mari Dohrn, postdoctoral student, Maria Hagströmer, associate professor, Charlotte Edwardson, senior lecturer, Thomas Yates, professor, Eric Shiroma, scientist, Sigmund A Anderssen, professor, I-Min Lee, professor

Issue&Volume: 21 August 2019

Abstract: 

Objective To examine the dose-response associations between accelerometer assessed total physical activity, different intensities of physical activity, and sedentary time and all cause mortality.

Design Systematic review and harmonised meta-analysis.

Data sources PubMed, PsycINFO, Embase, Web of Science, Sport Discus from inception to 31 July 2018.

Eligibility criteria Prospective cohort studies assessing physical activity and sedentary time by accelerometry and associations with all cause mortality and reported effect estimates as hazard ratios, odds ratios, or relative risks with 95% confidence intervals.

Data extraction and analysis Guidelines for meta-analyses and systematic reviews for observational studies and PRISMA guidelines were followed. Two authors independently screened the titles and abstracts. One author performed a full text review and another extracted the data. Two authors independently assessed the risk of bias. Individual level participant data were harmonised and analysed at study level. Data on physical activity were categorised by quarters at study level, and study specific associations with all cause mortality were analysed using Cox proportional hazards regression analyses. Study specific results were summarised using random effects meta-analysis.

Main outcome measure All cause mortality.

Results 39 studies were retrieved for full text review; 10 were eligible for inclusion, three were excluded owing to harmonisation challenges (eg, wrist placement of the accelerometer), and one study did not participate. Two additional studies with unpublished mortality data were also included. Thus, individual level data from eight studies (n=36 383; mean age 62.6 years; 72.8% women), with median follow-up of 5.8 years (range 3.0-14.5 years) and 2149 (5.9%) deaths were analysed. Any physical activity, regardless of intensity, was associated with lower risk of mortality, with a non-linear dose-response. Hazards ratios for mortality were 1.00 (referent) in the first quarter (least active), 0.48 (95% confidence interval 0.43 to 0.54) in the second quarter, 0.34 (0.26 to 0.45) in the third quarter, and 0.27 (0.23 to 0.32) in the fourth quarter (most active). Corresponding hazards ratios for light physical activity were 1.00, 0.60 (0.54 to 0.68), 0.44 (0.38 to 0.51), and 0.38 (0.28 to 0.51), and for moderate-to-vigorous physical activity were 1.00, 0.64 (0.55 to 0.74), 0.55 (0.40 to 0.74), and 0.52 (0.43 to 0.61). For sedentary time, hazards ratios were 1.00 (referent; least sedentary), 1.28 (1.09 to 1.51), 1.71 (1.36 to 2.15), and 2.63 (1.94 to 3.56).

Conclusion Higher levels of total physical activity, at any intensity, and less time spent sedentary, are associated with substantially reduced risk for premature mortality, with evidence of a non-linear dose-response pattern in middle aged and older adults.

DOI: https://doi.org/10.1136/bmj.l4570

Source: https://www.bmj.com/content/366/bmj.l4570