老年人衰弱与心脏自主神经功能的相关性分析

The correlation between frailty and cardiac autonomic nervous function in elderly patients

目的︰评估老年人衰弱与心脏自主神经功能的相关性。方法﹐对≥65岁老年住院患者用临床衰弱分级进行衰弱评估,应用动态心电图进行心率变异性(HRV)分析评估心脏自主神经功能。结果﹑本研究纳入住院老年患者共180例,其中衰弱患者66例、非衰弱患者114例,衰弱组年龄(79.8±6.0)岁,显著高于非衰弱组(75.0±6.3)岁(t=5.030、P<0.001);衰弱组高血压、卒中/短暂脑缺血发作(TIA)、心力衰竭及骨关节炎患者比例高于非衰弱组(均P<0.05);与非衰弱组比较,衰弱组正常窦性心搏(NN)间期标准差(SDNN)[103.0(76.0,121.2)ms比107.5(92.0,136.0)ms,Z=-2.108,P=0.035].5 min NN间期平均值标准差(SDANN)[86.0(67.7,106.5)ms比97.5(78.0,126.0)ms,Z=-2.694,P=0.007]、标化低频功率(LFnorm)[(53.1±13.0)nU比(59.3±13.9)nU,t=-3.024,P=0.003]及低频功率/高频功率比值(LF/HF)[1.2(1.0,1.4)比1.4(1.1,1.7),Z=-3.041,P=0.002]更低,标化高频功率(HFnorm)[(36.8±9.2)nU比(32.2±10.7)nU,t=3.033,P=0.003)更高;衰弱组SDANN<92 ms、LFnorm<50 nU、HFnorm>32 nU、LF/HF<1.5发生率分别为59.1%(39/66),42.4%(28/66)、72.7%(48/66),84.8%(56/66),均显著高于非衰弱组41.2%(47/114)、22.8%(26/114)、49.1%(56/114)、65.8%(75/114)。多因素Logistic回归分析结果显示,LFnorm,HFnorm,LF/HF与衰弱相关(OR=0.971,1.039,0.333,均P<0.05),HFnorm>32 nU、LF/HF≤1.5是衰弱的危险因素(OR=2.401、2.773,均P<0.05)。结论老年衰弱患者心脏自主神经功能受损,交感神经与迷走神经调节失衡,应关注老年衰弱患者的HRV。

Objective To assess the correlation between frailty and cardiac autonomic nervoussystem function in elderly patients.Methods Elderly hospitalized patients aged 65 years and overwere enrolled and assessed for frailty by using the clinical frailty scale.Cardiac autonomic modulationwas evaluated by heart rate variabilnty analysis through 24 h electrocardiogram recording.Results Atotal of 180 elderly patients were enrolled in this study,including 66 patients with frailty and 114 patients without frailty.The mean age of the frailty group was higher than that of the non-frailty group(79.8±6.0 vs.75.0±6.3,t=5.030,P<0.001).The proportions of patients with hypertension,stroke/transient cerebral ischemia attack(TIA),heart failure and osteoarthritis were higher in thefrailty group than in the non-frailty group(all P<0.05).Compared with the non-frailty group,thestandard deviation of normal-to-normal intervals(SDNN)[103.0(76.0,121.2)vs.107.5(92.o,136.0),Z=-2.108,P=0.035],the standard deviation of the averages of NN intervals in all 5-minsegments(SDANN)[86.0(67.7,106.5)vs.97.5(78.0,126.0),Z=-2.694,P=0.007],normalizedlow frequency(LFnorm)(53.1±13.0 vs.59.3±13.9,t=-3.024,P=0.003)and low frequency/highfrequency(LF/HF)ratio[1.2(1.0,1.4)vs.1.4(1.1,1.7),Z=-3.041,P=0.002]were decreasedand normalized high frequency(HFnorm)(36.8±9.2 vs.32.2±10.7,t=3.033,P=0.003)wasincreased in the fralty group.HFnorm in the frailty group was significantly higher than that in thenon-frailty group.The incidents of SDANN<92 ms,LFnorm≤50 nU,HFnorm>32 nU and LF/HFratio<1.5 were higher in the frailty group than in the non-frailty group(59.1%or 39/66 vs.41.2%or 47/114,42.4%or 28/66 vs.22.8%or 26/114,72.7%or 48/66 rs.49.1%or 56/114,84.8%or56/66 vs.65.8%or 75/114,χ^(2)=5.346,7.660,9.547,7.664,P=0.021,0.006,0.002,0.006).Logistic multivariate regression analysis showed that LFnorm,HFnorm and LF/HF ratio werecorrelated with frailty(OR=0.971,1.o39 and 0.333,all P<0.05),and HFnorm>32 nU and LF/HFratio<1.5 were risk factors for frailty(OR=2.401 and 2.773,both P<0.05).ConclusionsCardiac autonomic nerve system function is impaired in elderly frail patients,with the imbalancebetween the sympathetic and vagus nerves.Therefore particular attention should be paid to heart ratevariability in elderly patients with frailty.