Is it a transient, innocuous blip in blood pressure in the presence of an MD in clinic? Or, something quite different?
The most basic definition of white coat hypertension (WCH) is blood pressure elevation in the physician’s office/clinic in a patient with normal blood pressures obtained by 24-hour ambulatory blood pressure monitoring (ABPM) outside the office.1 More specifically, WCH is a clinic/office visit blood pressure of at least 140/90 mm Hg in a patient with 24-hour ambulatory reading of < 130/80 mm Hg; awake reading of <135/85 mm Hg; and sleeping reading of <120/70 mm Hg.1 WCH cannot be identified in the absence of 24-hour ABPM. The term “white-coat hypertension” can sometimes be used loosely and in jest; the truth is that it is a phenomenon whose meaning and cardiovascular risk implications are topics of both ongoing study as well as debate. But can the impact of WCH be minimized? Can it safely be characterized as a transient innocuous blip in blood pressure in response to the presence of a medical professional that poses no risk to patient? Let’s see.
Which of the following are true?
A. One half of patients with WCH have a higher risk for cardiovascular disease-in one study 73% higher than normotensive matched controls.
B. Patients with WCH develop increases in left ventricular mass.
C. WCH increases renal risks as measured by microalbuminuria and cystain-C.
D. In a trial that used antihypertensive agents to lower blood pressure in patients with WCH, daytime blood pressures were lowered and symptoms occurred.
Answer: Options A, B, and C are true; Option D is false.1-3
WCH is not a benign clinical situation. Lowering blood pressures in persons with WCH does not lead to symptomatic reductions in outside office ambulatory blood pressures.1 That means that antihypertensive agents are tolerated in “white coat hypertensives,” hinting that these folks have elevated blood pressures amenable to therapy. These people seem to really have hypertension even if it is not present under all circumstances. Regarding antihypertensive therapy in WCH, cystatin-C, a marker for renal injury, was reduced to normotensive levels in patients with WCH treated with antihypertensives.1
Patients with WCH should be monitored closely, be considered at heightened cardiovascular risk and, as such, be counseled on risk factor modification. In concert with the earlier observation that antihypertensives do not precipitate low blood pressure in patients with WCH, we may be seeing more and more of these patients treated for their elevated in-office blood pressures despite normal at- home blood pressure. This approach makes sense since WCH is associated with vascular risk.
1. Campbell PT, White WB. Utility of ambulatory blood pressure monitoring for the management of hypertension. Curr. Opin. Cardiol. 2017.
2. Briasoulis A, Androulakis E, Palla M, et al. White-coat hypertension and cardiovascular events: a meta-analysis. J Hypertens 2016; 34:593-599.
3. Tadic M, Cuspidi C, Ivanovic B, et al The impact of white coat hypertension on cardiac mechanics. J Clin Hypertension (Greenwich). 2016;18:617-622. doi: 10.1111/jch.12826. Epub 2016 Apr 21.