Abstract: Background　High-salt diet is a risk factor for hypertension，stroke and cardiovascular disease.Blood pressure variability（BPV） is a reliable independent predictor of cardiovascular events and deaths.There are few studies on the relationship between salt intake and BPV.Objective　To explore the relationship between salt intake and BPV in hypertensive populations in Ningxia.Methods　We selected 605 hypertensive residents from a community in Yinchuan during January 2015 to January 2017 by opportunistic screening，priority population screening and physical examination screening.By a questionnaire survey and a physical examination，we collected their demographic data，history of diseases，and behavioral risk factors for cardiovascular disease，levels of triglyceride，total cholesterol（TC），low-density lipoprotein cholesterol（LDL-C），high-density lipoprotein cholesterol（HDL-C），and fasting blood glucose（FBG）via analyzing the venous blood sample，and 24-hour blood pressure via 24-hour ambulatory blood pressure monitoring，and daily salt intake determined gravimetrically.We divided the residents into low-salt intake group（n=332）and high-salt intake group（n=273）according to average daily salt intake，and coMAPred demographic data，laboratory test results and 24-hour blood pressure between the groups.We performed multiple linear regression analysis to identify associated factors for BPV.Results　Two groups had significant differences in sex，BMI，prevalence of tobacco consumption，alcohol consumption，exercise frequency and family history of cardiovascular disease（P<0.05）.High-salt intake group showed lower average HDL-C and TC than low-salt intake group（P<0.05）.Two groups showed no significant differences in mean daytime SBP（dSBP），dDBP，and dMAP，mean nighttime SBP（nSBP），nDBP，and nMAP，and mean 24 h SBP，24 hDBP，and 24 hMAP（P>0.05）.CoMAPred with the low-salt intake group，high-salt intake group had higher standard deviation（SD） of dSBP（dSBPSD），dMAPSD，24 hSBPSD，24 hDBPSD，and 24 hMAPSD（P<0.05）.Multiple linear regression analysis showed that in the unadjusted model，in the model with adjusted sex，age，minzu，and BMI，and in the model with adjusted sex，age，minzu，BMI，prevalence of tobacco and alcohol consumption，labor intensity，exercise frequency，history of diabetes，and family history of cardiovascular disease，daily salt intake was significantly associated with dSBPSD，and dMAPSD（P<0.05）.Conclusion　 Salt intake is an influencing factor for dSBPSD and dMAPSD in hypertensive populations in Ningxia.So guidance on eating a salt-restricted diet is essential for the control of blood pressure and BPV in this group.

Key words: Hypertension；Sodium chloride, dietary；Blood pressure variability；Root cause analysis

摘要： 背景　高盐饮食是高血压、脑卒中及心血管疾病危险因素，血压变异性（BPV）是可靠的心血管事件和死亡的独立预测因子，目前摄盐量与BPV关系的研究较少。目的　探讨宁夏地区社区高血压人群摄盐量与BPV的关系。方法　于2015年1月—2017年1月在银川市某社区采用机会性筛查、重点人群筛查、健康体检筛查等筛查方法选取605例高血压患者为研究对象。通过问卷调查和体格检查收集患者人口统计学指标、疾病史、心血管疾病相关行为等资料，采集空腹静脉血检测三酰甘油、总胆固醇（TC）、低密度脂蛋白胆固醇、高密度脂蛋白胆固醇（HDL-C）、空腹血糖等指标，并对其进行24 h动态血压监测。采用称重法计算患者每日盐摄入量，按摄盐总量分为低摄盐组332例和高摄盐组273例。比较低摄盐组和高摄盐组基本情况、实验室检查指标、动态血压监测结果，采用多元线性回归分析BPV的影响因素。结果　低摄盐组和高摄盐组性别、体质指数（BMI）、吸烟情况、饮酒情况、运动频率及心血管病家族史比较，差异有统计学意义（P<0.05）。高摄盐组HDL-C、TC低于低摄盐组（P<0.05）。低摄盐组和高摄盐组白天平均收缩压（dSBP）、白天平均舒张压（dDBP）、白天平均动脉压（dMAP）、夜间平均收缩压（nSBP）、夜间平均舒张压（nDBP）、夜间平均动脉压（nMAP）、24 h平均收缩压（24 hSBP）、24 h平均舒张压
（24 hDBP）、24 h平均动脉压（24 hMAP）比较，差异无统计学意义（P>0.05）。高摄盐组白天收缩压标准差（dSBPSD）、白天平均动脉压标准差（dMAPSD）、24 h 收缩压标准差（24 hSBPSD）、24 h舒张压标准差（24 hDBPSD）、24 h平均动脉压标准差（24 hMAPSD）高于低摄盐组（P<0.05）。多元线性回归分析结果显示，在未调整的模型，调整性别、年龄、民族、BMI模型，调整性别、年龄、民族、BMI、吸烟情况、饮酒情况、劳动强度、运动频率、糖尿病史、心血管病家族史模型中，摄盐量均是dSBPSD、dMAPSD的影响因素（P<0.05）。结论　高血压患者摄盐量是dSBPSD、dMAPSD的影响因素，指导高血压患者合理限盐饮食，对控制患者血压水平和BPV具有重要的临床意义。

关键词: 高血压, 氯化钠, 膳食, 血压变异性, 影响因素分析?