不同年龄健康被试者心率变异性的谱分析研究

EFFECT OF AGE ON SPECTRUM OF HEART RATE VARIABILITY IN HEALTHY MALESUBJECTS

对不同年龄健康男性被试者卧、立位条件下，心率变异性（ｈｅａｒｔｒａｔｅｖａｒｉａｂｉｌｉｔｙ，ＨＲＶ）谱高、低频成分随年龄变化的规律进行研究。结果表明：虽然各年龄组间卧、立位时的静息平均心率并无显著差别，但ＨＲＶ却随年龄的增长而明显降低，青年组ＨＲＶ谱高、低频谱峰功率均显著高于中年组、中老年组及老年组（Ｐ＜０．０５或Ｐ＜０．０１）；ＨＲＶ谱低频谱功率、高频谱功率及总功率均随年龄增长呈指数衰减规律。由卧位转为立位时，各年龄组高频谱功率及归一化高频谱参数均显著降低（Ｐ＜０．０５或Ｐ＜０．０１）；归一化低频谱参数显著增加，且青、中年组的变化幅度大于中老年组与老年组。上述结果提示，ＨＲＶ谱成分随年龄增长而降低可用指数函数衰减规律描述；在体位改变过程中，青年组与中年组对１Ｇ重力应激的心血管反应性大于中老年组与老年组。

The changes of low frequency(LF_(HRV)) and high frequency(HF_(HRV)) spectral components ofheart rate variability(HRV)with age have been studied in 42 healthy male subjects ranging from20 to 75yr.The results indicated that although the resting heart rate showed no singificant differ-ence among the different age groups,the overall HRV declined obviousely with aging.The resultsof spectral analysis further showed that:①both the LF_(HRV)and HF_(HRV)of young age group weregreater than those of middle, elderly and old age groups(P<0.05 orP<0.01),but there were nosignificant differences of HRV spectral components among the middle,elderly and old age groups(P>0.05);②the LF_(HRV)and HF_(HAV)as well as total spectral power (TP_(HRV))declinedexponentially with aging(P<0.0,and there seems to be a“threshold phenomenon”forHF_(HRV) decline at about 30yr;③ with the posture changing from supine to standing,the HF_(HRV)decreased significantly(P< 0.05 or P < 0.01)in all age groups;the normalized spectral parameterLF_(HRV,n)increased by 91%,90%,27%,and 40% (P<0.05, P<0.01 for young,middle,elderly,and old age groups respectively;the HF_HRV,n decreased by 50%,75%,and 37%(P<0.01)for young,middle,ahd old age groups respectively,the TP_HRV decreased and LF_HRV to HF_HRV ra-tio(RF_HRV)increased, but only the changes observed in the young and middle age groups werestatistically singificant(P<0.05,P<0.01).The above results showed that the decline in spectralcomponents of HRV with aging could be described by an exponential fitting and thecardiovascular responses of young and middle-aged subjects to the gravitational stress of 1Gwere greater than those of elderly and old aged subjects.