Obstructive sleep apnea syndrome (OSAS) is a sleep-related disease. Evidence has shown that OSAS may increase the risk of developing arterial stiffness (AS) , but the mechanism of action still needs to be further explored.

To explore the mediating effect of waist circumference (WC) and fasting plasma glucose (FPG) on the association between OSAS and AS.

A total of 1 053 health examinees were selected from Physical Examination Center, the First People's Hospital of Fuquan City from March 23 to November 30, 2022. General demographic data were collected. The risk of OSAS was assessed using the STOP-Bang Questionnaire (high or low risk of OSAS was diagnosed by STOP-Bang score ≥4 points or <4 points) . AS was assessed, and 553 cases with AS and 500 without were assigned to AS and non-AS groups, respectively. Multivariate Logistic regression analysis was used to explore the factors associated with AS. FPG was converted to exponential form (-2.576 1) to obtain the exponential value of FPG (FPGa) . Multiple linear model was used to analyze the relationship of OSAS with WC and FPGa. The mediation effect of WC and FPG between OSAS and AS was analyzed using Hayes Process models 4 and 6 in R.

AS and non-AS groups had statistically significant differences in mean age, sex ratio, prevalence of smoking and hypertension, mean body mass index, WC, neck circumference, FPG, triglyceride, and high-density lipoprotein cholesterol as well as the level of OSAS risk (P<0.05) . Multivariate Logistic regression analysis showed that compared with individuals with low-risk OSAS, the risk of AS increased in those with high-risk OSAS (P<0.05) , and the risk of AS increased by 0.048 times for every 1 cm increase in WC and 0.512 times for every 1 mmol/L increase in FPG (P<0.05) . Multiple linear regression analysis showed that OSAS was associated with WC and FPGa (P<0.05) , and WC was an associated factor of FPGa (P<0.05) . The chained multimediator model showed that OSAS directly affected the incidence of AS〔β=0.661, 95%CI (0.284, 1.038) 〕. The indirect mediation effect value (β) of the "OSAS→WC→AS" path was 0.224〔95%CI (0.073, 0.398) 〕, accounting for 20.86% of the total effect. The indirect mediation effect value (β) of the "OSAS→FPGa→AS" path was 0.115〔95%CI (0.024, 0.216) 〕, accounting for 10.71% of the total. The indirect mediation effect value (β) of the "OSAS→WC→FPGa→AS" path was 0.074〔95%CI (0.036, 0.126) 〕, accounting for 6.89% of the total.

WC and FPG may partially mediate the relationship between OSAS and AS. In addition, they are involved in the process of "OSAS→WC→FPGa→AS" as chained mediators. People with high risk of OSAS should actively control WC to reduce the possibility of developing central obesity, and regulate FPG to prevent the occurrence of AS.

阻塞性睡眠呼吸暂停综合征（OSAS）是与睡眠相关的一种疾病，有证据显示OSAS可能增加动脉硬化（AS）的发病风险，但其影响AS的机制尚需要进一步探索。

探讨腰围（WC）、空腹血糖（FPG）对OSAS与AS关联的中介效应。

纳入2022-03-23—11-30福泉市第一人民医院体检中心进行体检的1 053例体检人群为研究对象，收集研究对象的一般资料，采用睡眠呼吸暂停初筛量表评估研究对象的OSAS情况，将量表≥4分定义为OSAS高风险，<4分为OSAS低风险。评估AS情况，根据是否患有AS将研究对象分为未合并AS组（n=500）与合并AS组（n=553）。采用多因素Logistic回归分析探究研究对象发生AS的影响因素。将FPG进行指数值转换（-2.576 1），得到FPG指数转换值（FPGa），采用多重线性回归分析探究OSAS、WC及FPGa之间的关系。采用Hayes编制的R软件Process语法程序的模型4和模型6分析WC、FPG在OSAS和AS之间的中介效应。

未合并AS组与合并AS组研究对象年龄、性别、吸烟、高血压患病情况、BMI、WC、脖围、FPG、三酰甘油、高密度脂蛋白胆固醇、OSAS风险程度比较，差异有统计学意义（P<0.05）。多因素Logistic回归分析结果显示，与OSAS低风险人群比较，OSAS高风险人群发生AS风险增加（P<0.05），WC、FPG是发生AS的影响因素（P<0.05）。多重线性回归分析结果显示，OSAS是WC和FPGa的影响因素（P<0.05），WC是FPGa的影响因素（P<0.05）。链式多重中介效应模型分析结果表明，OSAS对AS发生风险具有直接影响〔β=0.661，95%CI（0.284，1.038）〕，"OSAS→WC→AS"路径间接中介效应值β=0.224〔95%CI（0.073，0.398）〕，占总效应的20.86%；"OSAS→FPGa→AS"路径间接中介效应值β=0.115〔95%CI（0.024，0.216）〕，占总效应的10.71%；"OSAS→WC→FPGa→AS"路径间接中介效应值β=0.074〔95%CI（0.036，0.126）〕，占总效应的6.89%。

WC、FPG在OSAS与AS的关系中可能单独发挥部分中介作用，同时还存在"OSAS→WC→FPGa→AS"的链式中介作用。OSAS高风险人群应当积极控制WC，避免中心性肥胖，调节FPG，防止AS的发生。