COPD患者心脏自主神经功能失调对运动能力的影响研究

Effect of Cardiac Autonomic Nerve Function Disturbances on Exercise Capacity in Patients with Chronic Obstructive Pulmonary Disease

目的探讨COPD患者心脏自主神经功能失调的特点及其对患者运动能力的影响。方法以病情稳定的COPD患者62例作为试验组,以同期健康查体者50例作为对照组。试验组进行肺功能测量、6min步行试验(6MWT)。两组均接受24h动态心电图检查并计算时域分析指标和频域分析指标以评估心脏自主神经功能。比较两组研究对象的心脏自主神经功能,采用Pearson相关分析和多元线性回归分析判断影响6MWD的相关因素。结果与对照组相比,COPD患者平均RR间期(MNN)、正常R-R间期的标准差(SDNN)、每5min内R-R间期标准差的平均值(SDNNI)、每5min内平均R-R间期的标准差(SDANN)、相邻R-R间期之差的均方根(rMSSD)、相邻R-R间期之差≥50ms的心搏占心搏总数的百分数(PNN50)和高频成分(HF)降低,低频成分(LF)升高。Pearson相关分析发现,6MWD与FEV1%预测值、FEV1/FVC、DLCO、MNN、SDNN、SDNNI、SDANN、rMS-DD、PNN50和HF呈正相关,与TLC、RV/TLC和LF呈负相关。多元线性回归分析发现,FEV1%预测值、MNN和LF与6MWD独立相关。结论 COPD患者存在心脏自主神经功能失调,交感神经张力增加,而迷走神经张力下降,并且影响COPD患者的运动能力,恢复自主神经系统平衡的治疗也许有助于提高COPD患者的运动耐力。

Objective To investigate the characteristics of cardiac autonomic nerve function disturbances and its effect on exercise capacity in patients with chronic obstructive pulmonary disease （COPD）. Methods Sixty two COPD patients in stable condition as study group and 50 healthy subjects as control group were enrolled in this study. Pulmonary function tests and six - minute walk test （6MWT） were performed in study group. Time domain measures and frequency domain measures were acquired by the 24 - hour hoter monitor to evaluate cardiac autonomic nerve function in both groups. Cardiac autonomic nerve function was compared between the two groups. Pearson＇s correlation and multiple linear regression analysis were performed to evaluate the association between 6MWD and other factors in study group. Results Compared with control group, mean RR （MNN） , normal RR intervallerinin standard deviation （SDNN）, standard deviation of normal - to - normal beats jndex （SDNNI） , standard deviation of the averages of normaI sinus to normal sinus （SDANN） , mean squared differences of the successive RR intervals （rMSDD） , fraction of consecutive normal sinus intervals that differ by more than 50 ms （PNN50） and high frequency （HF） were significantly lower in study group, while low frequency （LF） was significantly increased. In Pearson＇s correlation there was a significant positive correlation between FEV1% predicted, FEVI/FVC, DLCO, MNN, SDNN, SDNNI, SDANN, rMSDD, PNN50, HF and 6MWD. TLC, RV/TLC, LF were negatively correlated with 6MWD. In multiple linear regression analysis FEVt% predicted, MNN and LF were independent predictors of exercise capacity in patients with C OPD. Conclusion Impairment of cardiac autonomic nervous system regulation occurs in COPD patients, which is characterized with increased sympathetic tone and decreased vagal tone. Cardiac autonomic nerve function disturbances have a negative effect on exercise capacity in patients with COPD. Treatment aimed to restore the sympathovagal balance may contribute to improve exercise tolerance in COPD.