Roy T M, Peterson H R, Snider H L, Cyrus J, Broadstone V L, Fell R D, Rothchild A H, Samols E, Pfeifer M A
University of Louisville, School of Medicine, Kentucky.
Am J Med. 1989 Oct;87(4):382-8. doi: 10.1016/s0002-9343(89)80818-6.
Cardiomyopathy, coronary artery atherosclerosis, or autonomic neuropathy may affect the cardiovascular performance of the diabetic patient. To evaluate the role of parasympathetic nervous system activity on cardiovascular performance, 25 diabetic subjects who lacked symptoms, signs, or objective measurements of ischemia or cardiomyopathy were studied.
Diabetic subjects were classified according to their RR variation, an index of cardiac parasympathetic nervous system activity. Fourteen diabetic subjects had a normal RR variation of greater than 30 (D-NOR), and 11 diabetic patients had an abnormal RR variation of less than 20 (D-ABN). Fifteen age- and weight-matched, healthy, nondiabetic subjects (NOR) constituted the control group. All subjects had oxygen consumption, multigated acquisition determination of cardiac output, and work product measured before and during supine bicycle maximum exercise testing.
There was no difference in the resting cardiac output among the groups. Resting work product, however, was greatest in the D-ABN group when compared with performance in the other two groups (D-ABN: 11,500 +/- 800; D-NOR: 9,000 +/- 600; NOR: 8,700 +/- 400; p less than 0.0025). This was due to an increase in both heart rate (p less than 0.025) and systolic blood pressure (p less than 0.015). In the diabetic subjects, there was an inverse relationship between the RR variation and resting work product (r = 0.47, n = 25, p less than 0.005). In response to exercise, the percent increase in cardiac output at matched percent maximum oxygen uptake was greatest in the NOR, D-NOR, and D-ABN groups, respectively (analysis of variance, p less than 0.01). In the diabetic subjects, there was a significant relationship between the RR variation and the maximum percent change in cardiac output (r = 0.41, n = 25, p less than 0.02). Compared with the NOR group, the maximum increase in work product was impaired in diabetic subjects (p less than 0.002) and not different between the D-NOR and D-ABN groups.
The increase in resting work product and the poor cardiac output responses to exercise in the D-ABN group are due to a decrease in cardiac parasympathetic nervous system activity and can be suggested by an abnormal RR variation. This index of parasympathetic nervous system activity can help the physician identify that subset of diabetic patients that may need special consideration when exercise training is prescribed.
心肌病、冠状动脉粥样硬化或自主神经病变可能会影响糖尿病患者的心血管功能。为了评估副交感神经系统活动对心血管功能的作用，我们对25名没有缺血或心肌病症状、体征或客观测量证据的糖尿病患者进行了研究。
根据RR变异（心脏副交感神经系统活动的指标）对糖尿病患者进行分类。14名糖尿病患者的RR变异正常，大于30（D-NOR），11名糖尿病患者的RR变异异常，小于20（D-ABN）。15名年龄和体重匹配的健康非糖尿病受试者（NOR）组成对照组。所有受试者在仰卧位自行车最大运动试验前和试验期间均测量了耗氧量、多门控采集法测定的心输出量和做功量。
各组静息心输出量无差异。然而，与其他两组相比，D-ABN组的静息做功量最大（D-ABN：11,500±800；D-NOR：9,000±600；NOR：8,700±400；p<0.0025）。这是由于心率（p<0.025）和收缩压（p<0.015）均升高。在糖尿病患者中，RR变异与静息做功量呈负相关（r = 0.47，n = 25，p<0.005）。在运动时，在相同的最大摄氧量百分比下，心输出量增加的百分比在NOR组、D-NOR组和D-ABN组中分别最大（方差分析，p<0.01））。在糖尿病患者中，RR变异与心输出量的最大变化百分比之间存在显著关系（r = 0.41，n = 25，p<0.02）。与NOR组相比，糖尿病患者的做功量最大增加量受损（p<0.002），D-NOR组和D-ABN组之间无差异。
D-ABN组静息做功量增加和运动时心输出量反应不佳是由于心脏副交感神经系统活动降低，RR变异异常可提示这一点。副交感神经系统活动的这一指标可帮助医生识别在制定运动训练方案时可能需要特别考虑的糖尿病患者亚组。
