Lantelme P, Milon H, Vernet M, Gayet C
Service de Cardiologie, Hôpital de la Croix-Rousse, Lyon, France.
J Hypertens. 2000 Apr;18(4):383-9. doi: 10.1097/00004872-200018040-00005.
The blood pressure (BP) response to the doctor's visit, generally referred as the white coat (WC) response, is usually estimated by the difference between office BP (OBP) and ambulatory BP (ABP). The purpose of this study was to determine the validity of this estimation. To that end, we compared the real WC effect and the estimated WC effect (OBP-ABP) in terms of magnitude and consequences on target organs.
The study comprised 88 patients referred for hypertension. The real WC effect was measured using a Finapres device and expressed as the maximal WC effect (Max WC) or the average WC effect (Aver WC). For the estimation of target organ damages, the whole hypertensive group was separated into two groups according to the medians of the Aver WC, the Max WC, and the estimated WC effects, successively. Left ventricular mass index, E to A mitral wave ratio and pulse wave velocity were compared between groups as were serum creatinine, cholesterol and glucose levels.
The estimated WC effect proved to be a bad index of the real response to the doctor's visit as assessed by their difference of magnitude between the two (20 +/- 17, 12 +/- 12 and 30 +/- 14 mmHg as estimated WC, Aver WC and Max WC effects, respectively), their loose correlations (r=0.31, P=0.004 between estimated WC and Aver WC effects; r=0.27, P=0.01 between estimated WC and Max WC effects), and finally by the fact that they were in agreement in less than two-thirds of the patients for the categorization of the WC response. Concerning target organ damages, no difference in terms of cardiac mass, diastolic function, arterial distensibility, renal function and cardiovascular risk profile could be discerned between the groups with a high and a low WC effect, either real or estimated, when age and ABP were taken into account.
The present work supports the view that the true WC effect and its estimation are not equivalent. However, the way in which the WC response is defined does not alter its effect on target organs or cardiovascular risk profile.
血压（BP）对就诊的反应，通常称为白大衣（WC）反应，一般通过诊室血压（OBP）与动态血压（ABP）之差来估计。本研究的目的是确定这种估计方法的有效性。为此，我们从大小和对靶器官的影响方面比较了实际的WC效应和估计的WC效应（OBP - ABP）。
该研究纳入了88例因高血压前来就诊的患者。使用Finapres设备测量实际的WC效应，并表示为最大WC效应（Max WC）或平均WC效应（Aver WC）。为了评估靶器官损害情况，将整个高血压组根据Aver WC、Max WC和估计的WC效应的中位数依次分为两组。比较了两组之间的左心室质量指数、二尖瓣E/A波比值和脉搏波速度，以及血清肌酐、胆固醇和葡萄糖水平。
通过两者大小的差异（估计的WC效应、Aver WC效应和Max WC效应分别为20±17、12±12和30±14 mmHg）、松散的相关性（估计的WC效应与Aver WC效应之间r = 0.31，P = 0.004；估计的WC效应与Max WC效应之间r = 0.27，P = 0.01），以及最终不到三分之二的患者在WC反应分类上两者一致这一事实，证明估计的WC效应并不是对就诊实际反应的良好指标。关于靶器官损害，在考虑年龄和ABP的情况下，实际或估计的WC效应高的组和低的组之间，在心脏质量、舒张功能、动脉弹性、肾功能和心血管风险状况方面没有差异。
目前的研究支持这样的观点，即真正的WC效应与其估计并不等同。然而，WC反应的定义方式并不会改变其对靶器官或心血管风险状况的影响。
