Does White Coat Hypertension Require Treatment Over Age 80?

Abstract

A ccurate measurement of blood pressure (BP) is an essential feature of any trial aiming to determine the relationship between BP reduction and outcome. BP control was the source of a controversy surrounding the results of the Heart Outcomes Prevention Evaluation (HOPE) trial, which claimed additional benefits from the use of an angiotensin-converting enzyme inhibitor (ramipril) versus placebo, because the between-group difference in clinic BP (CBP) was only 3/2 mm Hg.1 The beneficial effect was estimated to be 3 times that expected for this small difference in BP, 2 however, the possibility of a greater difference in BP was suggested by a small substudy of HOPE that measured ambulatory BP (ABP) and found a between-group difference of 10/4 mm Hg. 3ABP does not exactly mirror CBP, even if a fixed correction factor is used and the timing of the CBP measurement during the day is taken into account, for example, by comparing morning ABP values with morning CBP. The difference between CBP and ABP also depends on the degree of the alarm response induced in the office and varies from person to person, method of measurement, and the observer. This office or alarm response tends to increase with age 4,5 and decrease with the familiarity with the measurement. Furthermore, the machine used to measure ABP or CBP may over-or underestimate BP. When CBP is above normal and ABP is judged to be normal, then white coat hypertension (WCH) is said to be present. Importantly, it has long been considered desirable to avoid pharmaceutical treatment in those with WCH, because it has been suggested that active treatment does not lower ABP in this condition and also does not reduce cardiovascular events. Abstract-White coat hypertension is considered to be a benign condition that does not require antihypertensive treatment.Ambulatory blood pressure (ABP) was measured in 284 participants in the Hypertension in the Very Elderly Trial (HYVET), a double-blind randomized trial of indapamide sustained release 1.5 mg±perindopril 2 to 4 mg versus matching placebo in hypertensive subjects (systolic blood pressure 160-199 mm Hg) aged >80 years. ABP recordings (Diasys Integra II) were obtained in 112 participants at baseline and 186 after an average follow-up of 13 months. At baseline, clinic blood pressure (CBP) exceeded the morning ABP by 32/10 mm Hg. Fifty percent of participants fulfilled the established criteria for white coat hypertension. The highest ABP readings were in the morning (average 140/80 mm Hg), the average night-time pressure was low at 124/72 mm Hg, and the average 24-hour blood pressure was 133/77 mm Hg. During follow-up, the systolic/diastolic blood pressure placebo-active differences averaged 6/5 mm Hg for morning ABP, 8/5 mm Hg for 24-hour ABP, and 13/5 mm Hg for CBP. The lowering of blood pressure over 24 hours supports the reduction in blood pressure with indapamide sustained release±perindopril as the explanation for the reduction in total mortality and cardiovascular events observed in the main HYVET study. Because we es...

Effect of Long-Term Antihypertensive Treatment on White-Coat Hypertension

“…This is an observation that could not be made in previous analyses of other interventional trials, 14,[17][18][19][20][21][22][23][24][25][26][27] because only in ELSA ABP was systematically measured before treatment and repeatedly during several years of treatment, 29 whereas in most other studies ABP monitoring was limited to a relatively small subgroup of patients or done during treatment only. As to the effects of treatment on office BP, our data were derived from a controlled trial, with treatment steps determined by protocol according to the achieved DBP.…”

“…15,16 Furthermore, the effect of treatment on ABP values of WCH individuals is by no means clear because the reports range from a marked ABP fall to an ABP fall with some drugs only to no ABP fall at all. 14,[17][18][19][20][21][22][23][24][25][26][27] Previous studies on the BP effects of antihypertensive treatment in WCH have usually assessed ABP by just one 24-hour recording, sometimes without a baseline reference value.14,28 Primary aim of the present study has been to address the issue in a more adequate fashion by taking advantage of the unique data provided by the European Lacidipine Study on Atherosclerosis (ELSA) trial, 29 the only prospective antihypertensive treatment trial in which all patients with moderate elevations of both systolic BP (SBP) and diastolic BP (DBP) had office and ABP measured (1) before randomization to treatment and (2) at 6-month (office BP) and 12-month (ABP) intervals during treatment over a follow-up of 4 years. The multiple office and ABP measurements during the treatment period allowed us to more properly address also other issues relevant to WCH, such as the modification with time of the difference between office and ABP, often defined as the WC effect, 14,30 and the effect of treatment on within 24 hours and visit-to-visit BP variability (short-and long-term variability) of WCH vis-à-vis sustained hypertensive individuals.…”

“…15,16 Furthermore, the effect of treatment on ABP values of WCH individuals is by no means clear because the reports range from a marked ABP fall to an ABP fall with some drugs only to no ABP fall at all. 14,[17][18][19][20][21][22][23][24][25][26][27] Previous studies on the BP effects of antihypertensive treatment in WCH have usually assessed ABP by just one 24-hour recording, sometimes without a baseline reference value.…”

White-Coat Hypertension: Do We Really Understand It Now?

“…It has been considered that either ABPM or HBPM are required in treated hypertensives in order to have a better idea of the real BP of the patients so as to avoid an inadequate further drop in BP that could provoke unwanted CV and/or renal damage [28,29]. Nevertheless, data from theHypertension in the Very Elderly Trial (HYVET) have shown positive data for the outcome of elderly hypertensive patients, albeit an estimate of 50 % of them presented WCH in the study [30]. The finding of any form of target organ damage in patients with WCH promotes the need to consider pharmacological therapy [2].…”

Antihypertensive treatment decreases arterial stiffness at night but not during the day. Results from the Hypertension in the Very Elderly Trial

“…[4][5][6] In the Hypertension in the Very Elderly Trial (HYVET) the effect on 24 hour BP and arterial stiffness with indapamide and perindopril was compared with matched placebo in very elderly (more than or equal to 80 years) hypertensive subjects. [7] A measure of arterial stiffness, the QKD interval (time interval between the QRS wave on the electrocardiogram (ECG) and the detection of the last Korotkoff sound during BP measurement over the brachial artery) is closely related to A-PWV [8] and was explored in a 24 hour ambulatory blood pressure substudy. [9] Since QKD measures the time taken for the pulse wave to travel from the heart to the recording point, it is negatively correlated with the velocity as given by PWV and is also negatively correlated with arterial stiffness.…”