久坐间断对成年人血管功能的急性影响与调节因素:荟萃分析

Acute effects and moderators of sedentary interruption on vascular function in adults:a Meta-analysis

目的:持续性地久坐行为会急性降低外周与中枢血管功能,进而加剧罹患心血管疾病风险。久坐间断可能是预防持续久坐对血管功能危害的潜在实用策略,但目前关于其急性功效的已有研究结论并不一致,也尚未得出具体的应用建议。文章旨在对久坐间断对成人外周与中枢血管功能的急性影响进行荟萃分析,并探究其调节因素。方法:基于PRISMA报告规范,以“interrupting”“sedentary”与“vascular function”等为文献检索特征词,于2024年3月检索Web of Science核心合集、PubMed和中国知网数据库。纳入久坐间断对成人外周与中枢血管功能的急性影响的急性随机交叉试验文献。基于Cochrane开发的Risk of Bias 2评估偏倚风险,并基于GRADE系统评价证据等级。使用R语言(版本4.2.0)中的“meta”与“metafor”包进行主效应合并(Hedge’s g作为效应量指标)、发表偏倚检验、亚组与回归分析。结果:纳入22篇随机交叉试验,共364例受试者(年龄21-70岁)。相比于持续不间断久坐,久坐间断急性提升外周血管血流量(Hedge’s g=0.48,95%CI:0.14-0.82,P<0.01,I2=63%,低证据等级)、剪切应力(Hedge’s g=0.65,95%CI:0.37-0.93,P<0.01,I^(2)=54%,中等证据等级)与血流介导的血管舒张功能(Hedge’s g=0.43,95%CI:0.15-0.72,P<0.01,I2=61%,中等证据等级)。疾病(亚组间P=0.01)与性别(亚组间P=0.01)对血流量的主效应合并有显著调节作用(亚组间P=0.01),间断方式(亚组间P=0.01)与频率(亚组间P=0.02)对剪切应力的主效应合并有显著调节作用。久坐间断改善外周血管剪切应力受年龄(β=-0.02,95%CI:-0.03-0.01,P=0.09)与体质量指数(β=-0.10,95%CI:-0.18至-0.02,P<0.01)影响。久坐间断改善血流介导的血管舒张功能受总间断次数(β=-0.09,95%CI:-0.17至-0.01,P=0.03)与试验期间久坐控制时长影响(β=-0.21,-0.34至-0.09,P<0.01);每增加1 h久坐时长与久坐间断对血流介导的血管舒张功能的急性提升效果降低0.67%相关(P<0.01),当久坐控制时间>6 h时,久坐间断的急性收益消失。定性系统综述发现,久坐间断对各类人群血管脉搏波速度无显著影响,但可能预防老年人因持续久坐引起的中枢血管功能下降。结论:久坐间断急性提升成人外周血管血流量(低证据强度)、剪切应力(中证据强度)与血流介导的血管舒张功能(中证据强度),并可能预防、保护老年人因持续久坐引起的中枢血管功能下降(非常低证据等级)。受试者特征(疾病因素、性别、年龄与体质量指数)、间断干预方案(方式、频率、总间断次数)与久坐控制时长均会影响久坐间断对血管功能的急性改善效果。建议各类成人通过爬楼等大肌肉群参与的运动方式,以较高频率(如,每40 min进行1次)进行单次至少5 min的中低强度运动间断久坐,且每日持续久坐的累积时长不要超过6 h。

OBJECTIVE:Prolonged sedentary behavior can acutely reduce peripheral and central vascular function,thereby increasing the risk of cardiovascular disease.Interrupting sedentary behavior may be a potential practical strategy to prevent vascular dysfunction caused by prolonged sitting.However,current research findings on its acute effects are inconsistent,and specific application recommendations have not yet been established.This study aims to perform a Meta-analysis on the acute effects of interrupting sedentary behavior on peripheral and central vascular function in adults and to explore its regulatory factors.METHODS:Following PRISMA reporting guidelines,literature search was conducted in March 2024 using the keywords of“interrupting,”“sedentary,”and“vascular function”in the Web of Science Core Collection,PubMed,and China National Knowledge Infrastructure(CNKI)databases.Acute randomized crossover trials addressing the acute effects of interrupting sedentary behavior on peripheral and central vascular function in adults were included.Risk of Bias 2 developed by Cochrane was used to assess bias risk,and the Grading of Recommendations Assessment,Development,and Evaluation(GRADE)system was used to evaluate the evidence level.The“meta”and“metaphor”packages in R(version 4.2.0)were used for main effect aggregation(Hedge’s g acted as the effect size indicator),publication bias testing,subgroup analysis,and regression analysis.RESULTS:Twenty-two randomized crossover trials involving 364 subjects(aged 21 to 70 years)were included.Meta-analysis results showed that compared with prolonged sitting,interrupting sedentary behavior acutely improved peripheral vascular blood flow volume(Hedge’s g=0.48,95%confidence interval:0.14-0.82,P<0.01,I²=63%,low evidence level),shear stress(Hedge’s g=0.65,95%confidence interval:0.37-0.93,P<0.01,I^(2)=54%,moderate evidence level),and flow-mediated dilation(Hedge’s g=0.43,95%confidence interval:0.15-0.72,P<0.01,I²=61%,moderate evidence level).Disease had a significant moderating effect on the main effect aggregation for blood flow volume(P=0.01 between subgroups),while the mode(P=0.01 between subgroups)and frequency(P=0.02 between subgroups)of interruptions had significant moderating effects on shear stress.Improvements in peripheral vascular shear stress from interrupting sedentary behavior were affected by age(β=-0.02,95%confidence interval:-0.03-0.01,P=0.09)and body mass index(β=-0.10,95%confidence interval:-0.18 to-0.02,P<0.01).Improvements in flow-mediated dilation were influenced by the total number of interruptions(β=-0.09,95%confidence interval:-0.17 to-0.01,P=0.03)and the duration of sitting during the control period(β=-0.21,95%confidence interval:-0.34 to-0.09,P<0.01).Each additional hour of sitting was associated with a 0.67%reduction in the acute improvement effect of flow-mediated dilation from interrupting sedentary behavior(P<0.01),and acute benefits disappeared when sitting control time exceeded 6 hours.A qualitative systematic review found that interrupting sedentary behavior did not significantly affect pulse wave velocity in various populations but could effectively prevent central vascular function decline in older adults due to prolonged sitting.CONCLUSION:Interrupting sedentary behavior acutely improves peripheral vascular blood flow volume(low evidence level),shear stress(moderate evidence level),and flow-mediated dilation(moderate evidence level)in adults and may prevent or protect against central vascular function decline in older adults due to prolonged sitting(very low evidence level).Characteristics of subjects(disease factors,sex,age,and body mass index),interruption intervention schemes(mode,frequency,total number of interruptions),and duration of sitting control all influence the acute improvement effects of interrupting sedentary behavior on vascular function.It is recommended that adults interrupt sedentary behavior with exercises involving large muscle groups,such as stair climbing,at high frequencies(e.g.,once every 40 minutes)with at least 5 minutes of moderate-to low-intensity activity each time,and limit the cumulative duration of prolonged sitting to no more than 6 hours per day.