摘要目的:探索高血压人群体力活动在休闲静坐行为与肥胖指标关联的中介效应。方法:基于中国慢性病前瞻性研究项目（CKB）苏州市吴中区基线数据，选择高血压人群并剔除自报患冠心病、脑卒中和肿瘤等慢性疾病的个体，最终纳入分析20 178人。采用中介效应模型分析静坐行为与肥胖指标关联中体力活动的中介效应。结果:调整年龄、性别、吸烟、饮酒、文化程度、肉类摄入、新鲜水果摄入等因素后，休闲静坐行为与体力活动呈负相关（ β=-0.246， P<0.001）；与肥胖指标如体脂比（ β=0.061， P<0.001）、腰围（ β=0.087， P<0.001）和BMI（ β=0.071， P<0.001）呈正相关。纳入中介变量体力活动后，休闲静坐行为对肥胖指标的直接作用仍有统计学意义；控制休闲静坐行为后，体力活动与体脂比、腰围和BMI呈负相关（ β值分别为-0.052，-0.083和-0.028，均 P<0.001）。中介效应分析显示，体力活动在休闲静坐行为对体脂比、腰围和BMI的影响中均存在部分中介效应，中介效应占其总效应的比例分别为20.820%，23.421%和9.915%。对性别分层分析后，体力活动的中介效应在男女性中不相同，女性体力活动在休闲静坐行为与各肥胖指标间存在中介效应，而男性体力活动在休闲静坐行为与体脂比和腰围的关联中存在中介效应。 结论:体力活动在休闲静坐行为对肥胖指标的影响中均具有部分中介效应，高血压人群应增加体力活动水平，减少长时间休闲静坐以获得较好的健康效果。

abstractsObjective:To explore the mediating effect of physical activity on association between sedentary leisure-time and obesity indexes among hypertensive individuals.Methods:After excluding of those with a prior history of heart disease, stroke and cancer, a total of 20 178 hypertensive participants in the China Kadooire Biobank (CKB) study from Wuzhong district of Suzhou city were included. Mediating effect analysis was used to analyze the mediating effect of physical activity (PA) on correlation between sedentary leisure-time and body fat percentage (BFP), waist circumference (WC) and body mass index (BMI).Results:After adjusted for age, gender, smoking status, alcohol consumption, education levels, intake frequencies of meat and intake frequencies of fresh fruit, sedentary leisure-time (SLT) was negatively correlated with PA ( β=-0.246, P<0.001), but positively associated with BFP ( β=0.061, P<0.001), WC ( β=0.087, P<0.001) and BMI ( β=0.071, P<0.001). After including the mediator variable PA, the direct effect of SLT on obesity index was still significant. PA was negatively correlated with BFP, WC and BMI ( β=-0.052, -0.083 and -0.028, respectively, P<0.001). Analysis of mediating effect indicated that the association of SLT with BFP, WC and BMI were partly mediated by PA, the proportion of mediating effect was 20.820%, 23.421% and 9.915%. Stratified by gender, PA had mediating effect on SLT and all obesity indexes in women, while only on SLT and BFP and WC in men. Conclusions:There is a significant mediating effect of PA on correlation between SLT and obesity indexes among hypertensive individuals. Hypertensive patients should increase the level of physical activity and reduce sedentary behavior to achieve a profounder healthy effect.