Spallone V, Bernardi L, Maiello M R, Cicconetti E, Ricordi L, Fratino P, Menzinger G
Department of Internal Medicine, Tor Vergata University, Rome, Italy.
Clin Sci (Lond). 1996;91 Suppl:105-7. doi: 10.1042/cs0910105supp.
We performed four cardiovascular tests of autonomic function (deep breathing, lying to standing, Valsalva manoeuvre, postural hypotension) and simultaneous 24h recordings of blood pressure (BP) and ECG in 35 normotensive diabetic subjects. Autoregressive power spectrum analysis of RR interval variability was applied to 24h ECG recordings to obtain for day and night periods power of low- (0.03-0.15 Hz, LF) and high-frequency (0.18- 0.40 Hz, HF) components, relative markers of sympathetic and vagal activity respectively, and their ratio (LF/HF), assumed as index of sympathovagal balance. Eighteen patients showed normal cardiovascular tests, 6 patients one abnormal heart rate test, 5 patients two abnormal heart rate tests, and 6 patients also abnormal postural hypotension test. In diabetic patients with increasing degree of autonomic neuropathy, there was a progressive reduction of day-night change in systolic BP (p < 0.01), of LF during the day (p < 0.01), of HF during the night (p < 0.04), of day-night change in HF (p < 0.02), and of day-night change in HF/LF (p < 0.03). Day-night change in systolic BP was related to postural hypotension (p < 0.001) and to deep breathing (p < 0.01). Day LF was related to lying to standing (p < 0.001), to postural hypotension (p < 0.005) and to deep breathing (p < 0.007). Night HF was related to deep breathing (p < 0.0002) and to lying to standing (p < 0.02). Day-night change in HF/LF was slightly related to deep breathing, lying to standing, and to postural hypotension (p < 0.04). In a multiple regression analysis including age, diabetes duration, and cardiovascular tests as independent variables, day-night change in BP and day LF were only related to postural hypotension, whereas night HF was related to deep breathing. In conclusion, in diabetic patients with increasing autonomic damage, there is a progressive impairment of nocturnal fall of BP and of sympathetic activity during the day, blunted nocturnal increase of vagal activity and lower circadian variation in sympathovagal balance. The significant but not very close correlation of day-night pattern of BP and sympathovagal activity to standard cardiovascular reflex tests, supports the independent usefulness of 24h BP monitoring and spectral analysis of heart rate variability in diabetic neuropathy.
我们对35名血压正常的糖尿病患者进行了四项自主神经功能的心血管测试（深呼吸、平卧位到站立位、瓦尔萨尔瓦动作、体位性低血压），并同时进行了24小时血压（BP）和心电图记录。对24小时心电图记录应用RR间期变异性的自回归功率谱分析，以获取白天和夜间时段低频（0.03 - 0.15 Hz，LF）和高频（0.18 - 0.40 Hz，HF）成分的功率，分别作为交感神经和迷走神经活动的相对指标，以及它们的比值（LF/HF），将其作为交感迷走神经平衡指数。18名患者心血管测试正常，6名患者一项心率测试异常，5名患者两项心率测试异常，6名患者体位性低血压测试也异常。在自主神经病变程度增加的糖尿病患者中，收缩压的昼夜变化（p < 0.01）、白天的LF（p < 0.01）、夜间的HF（p < 0.04）、HF的昼夜变化（p < 0.02）以及HF/LF的昼夜变化（p < 0.03）均逐渐降低。收缩压的昼夜变化与体位性低血压（p < 0.001）和深呼吸（p < 0.01）有关。白天的LF与平卧位到站立位（p < 0.001）、体位性低血压（p < 0.005）和深呼吸（p < 0.007）有关。夜间的HF与深呼吸（p < 0.0002）和平卧位到站立位（p < 0.02）有关。HF/LF 的昼夜变化与深呼吸、平卧位到站立位和体位性低血压略有相关（p < 0.04）。在一项多元回归分析中，将年龄、糖尿病病程和心血管测试作为自变量，血压的昼夜变化和白天的LF仅与体位性低血压有关，而夜间的HF与深呼吸有关。总之，在自主神经损伤程度增加的糖尿病患者中，夜间血压下降和白天交感神经活动逐渐受损，夜间迷走神经活动增加减弱，交感迷走神经平衡的昼夜变化降低。血压和交感迷走神经活动的昼夜模式与标准心血管反射测试有显著但并非非常密切的相关性，这支持了24小时血压监测和心率变异性频谱分析在糖尿病神经病变中的独立实用性。
