Karavanaki K, Kazianis G, Konstantopoulos I, Tsouvalas E, Karayianni C
Diabetic Clinic, Second Department of Pediatrics, University of Athens, P&A Kyriakou Children's Hospital, Athens, Greece.
J Endocrinol Invest. 2008 Apr;31(4):289-96. doi: 10.1007/BF03346360.
Diabetic cardiomyopathy is a well-defined complication of diabetes that occurs in the absence of ischemic heart disease or hypertension. Moreover impaired circadian blood pressure (BP) variation has been associated with autonomic dysfunction. The aim of our study was to evaluate diurnal BP fluctuations and autonomic function and their association with left ventricular function in adolescents with Type 1 diabetes mellitus (T1DM). In 48 normotensive, normoalbuminuric diabetic adolescents, with a mean (+/-SD) age of 17.3 (+/-4.1) yr and a mean (+/-SD) diabetes duration of 8.5 (+/-3.3) yr, 24-h ambulatory BP was recorded. Moreover 24-h heart rate (HR) monitoring was performed. Myocardial structural parameters were studied by echocardiogram. Left ventricular end-diastolic (EDDLV) and end-systolic diameters (ESDLV) were estimated and left ventricular mass index (LVMI) was calculated using the Devereux formula. The patients were divided into 2 groups according to the absence of decrease (non-dippers) or the decrease (dippers) of nocturnal diastolic BP (DBP). The non-dippers showed, in comparison with the dippers, reduced mean 24-h HR (79.6 vs 84.0 beats/min, p=0.05) and reduced mean day-time HR (81.3 vs 86.0 beats/min, p=0.05). The nondippers also presented greater ESDLV (28.7 vs 25.9 mm, p=0.001) and EDDLV (47.8 vs 45.1 mm, p=0.040), and LVMI (90.2 vs 78.3 g/m2, p=0.044), in comparison with the dippers. During stepwise multiple regression, the most important variables affecting LVMI were mean HR (day): (b=-0.40, p=0.001), high frequency domain variable of HR variability (b=0.38, p=0.016) and glycosylated hemoglobin (b=0.67, p=0.001). In conclusion, we found that a group of normotensive diabetic adolescents with impaired nocturnal BP reduction, also had autonomic dysfunction, together with impaired left ventricular function. These findings suggest that there is a close relationship between autonomic function and left ventricular remodeling in patients with T1DM, which may be attributed to altered diurnal BP profile, autonomic neuropathy and poor glycemic control.
糖尿病性心肌病是糖尿病一种明确的并发症，发生于无缺血性心脏病或高血压的情况下。此外，昼夜血压（BP）变化受损与自主神经功能障碍有关。我们研究的目的是评估1型糖尿病（T1DM）青少年的昼夜血压波动和自主神经功能及其与左心室功能的关系。在48名血压正常、尿白蛋白正常的糖尿病青少年中，平均（±标准差）年龄为17.3（±4.1）岁，平均（±标准差）糖尿病病程为8.5（±3.3）年，记录24小时动态血压。此外，进行24小时心率（HR）监测。通过超声心动图研究心肌结构参数。估计左心室舒张末期（EDDLV）和收缩末期直径（ESDLV），并使用Devereux公式计算左心室质量指数（LVMI）。根据夜间舒张压（DBP）是否下降（非杓型）或下降（杓型）将患者分为两组。与杓型患者相比，非杓型患者的平均24小时心率降低（79.6对84.0次/分钟，p = 0.05），平均日间心率降低（81.3对86.0次/分钟，p = 0.05）。与杓型患者相比，非杓型患者的ESDLV（28.7对25.9毫米，p = 0.001）、EDDLV（47.8对45.毫米，p = 0.040）和LVMI（90.2对78.3克/平方米，p = 0.044）也更大。在逐步多元回归分析中，影响LVMI的最重要变量是平均心率（日间）：（b = -0.40，p = 0.001）、心率变异性高频域变量（b = 0.38，p = 0.016）和糖化血红蛋白（b = 0.67，p = 0.001）。总之，我们发现一组夜间血压降低受损的血压正常的糖尿病青少年也存在自主神经功能障碍以及左心室功能受损。这些发现表明，T1DM患者的自主神经功能与左心室重塑之间存在密切关系，这可能归因于昼夜血压模式改变、自主神经病变和血糖控制不佳。
