心率变异性与脑梗死关系的回顾性队列研究

A retrospective cohort study of the relationships between heart rate variability and cerebral ischemic stroke

目的使用回顾性队列研究方法,探索心率变异性(HRV)与脑梗死是否存在相关性。方法选择2020年3月至2022年6月期间因脑梗死在我院住院的1231例患者,搜索首次急性新发脑梗死前及发病后、符合24小时全程HRV分析要求的动态心电图记录。使用两独立样本的秩和检验比较脑梗死前、后时域及频域法HRV指标的差异性。按最高和最低四分位数把脑梗死前HRV指标分成3个水平,应用多因素Cox回归分析影响脑梗死发生速度的相关因素,应用Kaplan-Meier生存分析估计检测出不同HRV水平的时间距脑梗死的中位发病时间。结果检索到32例患者首次脑梗死前符合要求的记录45份,检查时年龄70.0(62.5,74.5)岁。相应患者脑梗死后的记录22份。脑梗死前、后时域及频域法HRV各指标的差异均无统计学意义(P>0.05)。在调整了年龄、性别及基础病等因素后,低频与高频能量比(LF/HF)水平是唯一与脑梗死发生速度相关的指标(P=0.008),与高水平(LF/HF>3.0)相比,低水平(LF/HF<1.5)的HR为4.31(95%CI1.41~13.17),无脑梗死生存时间显著缩短(χ^(2)=12.79,P=0.002),分别为5.0(95%CI 2.7~7.2)年和1.7(95%CI0.7~2.8)年。结论24小时全程HRV指标LF/HF<1.5是老年人较快发生脑梗死的风险指标。

Objective To explore the causality between the low heart rate variability(HRV)and cerebral ischemic stroke(CIS)by a retrospective cohort study.Methods We searched 24-hour ambulatory electrocardiography(AECG)records that met the long-term HRV analysis requirements in our hospital database,which were recorded before and after the first attack among the 1231 cerebral ischemic stroke inpatients in the past 2 years.The rank-sum test of two independent samples were used to compare the difference of the time domain HRV and frequency domain HRV between pre-stroke and post-stroke.Divided the HRV data of pre-stroke into 3 levels according the highest and the lowest quartile.Cox regression Model were applied to analyze the risk factor of HRV that influence the incident time of stroke,and interactions with age and sex and baseline conditions were assessed.Kaplan-Meier survival analysis were used to estimate the median stroke-free time.Results Forty-five pre-stroke records of 32 patients,and 22 post-stroke records of 21 patients among them were retrieved.There was no significant difference of all time or frequency domain HRV parameters between the pre-and post-stroke.The level of LF/HF ratio was the only index associated to the stroke-free time(P=0.008).Compared to the highest level group(LF/HF>3.0),the stroke-free time of the lowest level group(LF/HF<1.5)were significant shorter(χ^(2)=12.79,P=0.002),the HR was 4.31(95%CI:1.41-13.17),the median(95%CI)stroke-free years were 5.0(2.7~7.2)vs.1.7(0.7~2.8),respectively.Conclusions The LF/HF<1.5 of 24-hour-AECG-based HRV is an autonomic biomarker in CIS.