噪声、站立反应和肥胖指数与心率变异的关系

The relationship between noise, standing response, obesity index and heart rate variability

目的观察肥胖人群在静息和刺激状态下的心率变异反应。方法42名健康成人，年龄23-70岁，检测静息、噪声与站立应激时的心率变异性（HRV）。结果体脂量、体脂含量、腰／臀比值高者与低频（LF）（r=-0．34，r=-0．43，P〈0．01，r=-0．33，P〈0．05）和相邻R—R间期长度差的均方根（RMSSD）（r=-0．33，r=-0．35，r=-0．38，P〈0．05）有显著关联。静息、噪声和站立期间，NN间隔的标准差（SDNN）和低频／高频与正常组和肥胖组之间差异无统计学意义（P〉0．05）。结论虽然肥胖人群对刺激并无显著的HRV反应，但低频与体脂量、体脂百分值、腰／臀比值呈负相关，提示肥胖可引起心脏自主神经反应变化，增加心脏死亡率。

Objective To study of the relationship of the heart rate variability and the body mass index of obese subjects in noise and standing response. Methods The subjects were 42 healthy personsranging in age from 23 to 70 years. HRV measures at rest, during noise, and during standing. Results A higher level of fat mass, percentage fat, and waist/hip ratio were significantly associated with lower LF （r=-0.34,r=-0.43,P〈0.01, r=-0.33,P〈0.05） and lower RMSSD （r=-0.33,r=-0.35,r=-0.38,P〈0.05）. The change in SDNN was not dif- ferent （P〉0.05） between normal and obese group at rest and during noise and standing after adjusting for age, gender, and heart rate. Conclusion Although there was no significant HRV response to stimuli in obese persons, RMSSD （which reflect heart rate variability） and LF （which mainly reflects sympathetic activity） were negatively correlated with fat mass, percentage fat content, and waist/hip ratio at rest in obese persons. These results mean obesity can change cardiac autonomic nervous response, meaning that the mechanism by which obesity increases cardiac mortality would be explained, at least partially.