White Coat Hypertension

measuring blood pressure
Creating white coat hypertension. Darrin Klimek/Getty Images

It is surprisingly common for a person’s blood pressure reading to be substantially higher in the doctor’s office than it is during the course of a normal day. In up to 20% of people, the blood pressure in the doctor's office is high enough to be in the hypertensive range, but is in the normal range the rest of the time. This phenomenon is called “white coat hypertension.”

    White coat hypertension is diagnosed when blood pressure measurements in the doctors' office average higher than 140/90 mmHg, while blood pressure measurements outside the office reliably average less than 140/90 mmHg.

    White coat hypertension is really only an issue when it comes to diagnosing mild or “Stage 1” hypertension. If the blood pressure in the doctor’s office is in the “Stage 2” range (systolic pressure at least 160 mmHG or diastolic pressure at least 100 mmHG), that’s not white coat hypertension - it’s real hypertension.

    What Causes White Coat Hypertension?

    White coat hypertension is usually attributed to the anxiety which one may experience in a doctor's office. There is evidence that when this presumed anxiety is adjusted for - for instance, by having the blood pressure taken by a non-threatening nurse or technician rather than a harried doctor - the incidence of falsely elevated blood pressure readings goes down.

    Also, blood pressure readings in the doctor’s office tend to go down by the third or fourth visit (when the patient is used to the environment, and presumably is less anxious).

    However, it may not be entirely accurate for doctors to attribute most white coat hypertension to the anxiety created by their imposing personages.

    In many cases, the blood pressure measurements being made in doctors’ offices are simply done incorrectly.

    How Blood Pressure Is Supposed To Be Measured

    To diagnose hypertension with “spot” measurements (that is, blood pressure measurements made at some particular time, as in a doctor’s office), it is important to assure that the blood pressure is taken during what is called a period of “quiet restfulness.”

    Guidelines have been developed defining what “quiet restfulness” is for the purpose of diagnosing hypertension. Prior to measuring the blood pressure, the patient should be in a quiet, comfortable, warm environment, sitting for at least five minutes with their back and feet supported. The clinician should take at least two blood pressure measurements at least five minutes apart. If the readings vary by more than 5 mmHG, additional readings should be taken until they agree.

    What Really Happens

    That’s what is supposed to happen. If something else happens, the blood pressure reading has not been done during quiet restfulness, and should generally not be used to diagnose mild or moderate hypertension.

    As someone who has experienced plenty of blood pressure measurements as both a doctor and a patient, I can attest that this is usually not what happens. More typically the patient is placed naked (except for a flimsy rag) in a cold exam room, seated on an exam table without back support and with legs dangling, and the single blood pressure reading is done either by a rushing-about nurse or a doctor who is trying to save time by asking you questions about your medical history while taking your blood pressure.

    While many instances of white coat hypertension may indeed reflect the patient’s anxiety, many other instances may also reflect the infeasibility of actually achieving a state of "quiet restfulness" in a modern doctor’s office.

    What Is The Significance of White Coat Hypertension?

    Current evidence suggests that the cardiovascular risk associated with white coat hypertension lies somewhere between the risk seen in normal individuals and in individuals with straightforward hypertension.

    This makes sense, because not all people with white coat hypertension are the same. Some have real hypertension (and need to be treated), while others do not.

    What Should Be Done About White Coat Hypertension?

    Antihypertensive drug therapy is not recommended for people with white coat hypertension. However, it is reasonable to recommend appropriate lifestyle modifications aimed at reducing the blood pressure, as well as steps to reduce cardiac risk in general. This recommendation is reasonable for almost everyone.

    When a person is suspected of having white coat hypertension, it is important to determine whether they have real hypertension or not. If so, they need antihypertensive therapy. To sort this out, experts recommend one of two things.

    One option is to have the patient return to the office up to six times to have their blood pressure measured. If they have anxiety-produced white coat hypertension, studies show that their blood pressure will eventually “normalize” as they become acclimated to the doctor’s office environment.

    The second option, and likely the better one, is to use ambulatory blood pressure monitoring (ABPM). ABPM is a way of assessing a person's blood pressure throughout a one- or two-day period. Using ABPM to diagnose hypertension eliminates the need to simulate a condition of "quiet restfulness” in a doctor's office, where, more commonly, the prevailing sense is one of quiet panic. ABPM allows the physician to make a more reasoned assessment of whether a person with white coat hypertension has true hypertension, and needs to be treated.

    If ABPM is not feasible, evidence suggests that a reasonable alternative is home blood pressure monitoring.


    Pierdomenico SD, Cuccurullo F. Prognostic value of white-coat and masked hypertension diagnosed by ambulatory monitoring in initially untreated subjects: an updated meta analysis. Am J Hypertens 2011; 24:52.

    Mancia G, Bombelli M, Brambilla G, et al. Long-term prognostic value of white coat hypertension: an insight from diagnostic use of both ambulatory and home blood pressure measurements. Hypertension 2013; 62:168.

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