Brown M A, Buddle M L, Martin A
Department of Renal Medicine, St George Hospital and University of NSW Kogarah, Sydney, Australia.
Am J Hypertens. 2001 Dec;14(12):1263-9. doi: 10.1016/s0895-7061(01)02193-8.
Managing resistant hypertension is difficult and mostly involves expensive testing seeking an underlying secondary cause. This study was undertaken to determine 1) the extent of the white-coat phenomenon in patients with resistant hypertension, and 2) whether 24-h ambulatory blood pressure (BP) monitoring (ABPM) or having BP recorded by a nurse instead of the referring doctor could clarify how many apparently resistant hypertensives actually have controlled BP.
This study involved 611 patients with BP > or = 140/90 mm Hg who were referred for 24-h ABPM by their specialist or general practitioner, including 277 patients who were taking no antihypertensives (group 1), 216 taking one or two antihypertensive drugs (group 2), and 118 taking at least three antihypertensives in combination (group 3). Each had BP recorded by one of two nurses before 24-h ABPM. Controlled BP was defined as awake ambulatory BP <135/85 mm Hg and the white-coat effect was the difference between the BP recorded by the referring doctor or nurse and the average awake ambulatory BP.
Those with resistant hypertension (group 3) were older (61 years (12) v group 1: 46 years (14) and group 2: 56 (14) years; P < .001), but were of similar weight, height, and arm circumference to the other groups. Referral systolic, but not diastolic BP was higher in resistant hypertensives (mean 171/95 v 154/95 mm Hg and 164/94 mm Hg, respectively, P < .001 for systolic BP only). Twenty-eight percent of resistant hypertensives and 32% of those taking no antihypertensive drugs had normal awake ambulatory BP and the white-coat effect attributable to the referring doctor was always greater than that due to the nurse (range 16 to 26/12 to 14 mm Hg v 9 to 17/4 mm Hg, P < .001). Nurse recorded BP was highly sensitive (97%) in identifying awake hypertension but lacked specificity (57%) to replace ABPM.
Our results show that approximately one in four patients with apparent resistant hypertension referred for ABPM have controlled BP and one-third of patients referred for initial evaluation of office or clinic hypertension have normal BP using ABPM, ie, white-coat hypertension. Twenty-four-hour ABPM appears an appropriate initial step before further investigating or treating patients with apparently resistant hypertension.
管理顽固性高血压很困难，且大多需要进行昂贵的检查以寻找潜在的继发原因。本研究旨在确定：1）顽固性高血压患者中白大衣现象的程度；2）24小时动态血压监测（ABPM）或由护士而非转诊医生记录血压是否能明确有多少看似顽固性高血压患者的血压实际上得到了控制。
本研究纳入了611例收缩压≥140mmHg和（或）舒张压≥90mmHg的患者，这些患者由专科医生或全科医生转诊进行24小时ABPM，其中277例未服用抗高血压药物（第1组），216例服用1种或2种抗高血压药物（第2组），118例联合服用至少3种抗高血压药物（第3组）。每位患者在进行24小时ABPM前由两名护士之一记录血压。血压得到控制定义为清醒时动态血压＜135/85mmHg，白大衣效应为转诊医生或护士记录的血压与清醒时动态血压平均值之间的差值。
顽固性高血压患者（第3组）年龄更大（61岁（12），第1组：46岁（14），第2组：56（14）岁；P＜0.001），但体重、身高和臂围与其他组相似。顽固性高血压患者的转诊收缩压较高，但舒张压不高（平均分别为171/95mmHg、154/95mmHg和164/94mmHg，仅收缩压P＜0.001）。28%的顽固性高血压患者和32%的未服用抗高血压药物患者清醒时动态血压正常，转诊医生导致的白大衣效应总是大于护士导致的白大衣效应（范围为16至26/12至14mmHg比9至17/4mmHg，P＜0.001）。护士记录的血压在识别清醒时高血压方面敏感性很高（97%），但缺乏特异性（57%），无法替代ABPM。
我们的结果表明，转诊进行ABPM的看似顽固性高血压患者中约四分之一血压得到控制，转诊进行诊室或诊所高血压初始评估的患者中有三分之一使用ABPM时血压正常，即白大衣高血压。在对看似顽固性高血压患者进行进一步检查或治疗之前，24小时ABPM似乎是合适的初始步骤。
