White Coat Hypertension
‘White coat’ refers to a doctor’s white coat,
suggesting a clinical or medical environment. White coat hypertension
(sometimes called white coat syndrome) means having a high reading
only when your blood pressure is measured away from your normal
home environment, usually in a clinic or surgery.
People with white coat hypertension have high readings (140/90mmHg
or above) only when they have their blood pressure measured at their
doctor’s surgery or in a clinical environment, and have lower
blood pressure readings taken at home.
Causes of White Coat Syndrome
Blood pressure goes up and down throughout the day and night in
everyone, which is normal. For example, when you are excited or
in pain, when you have just exercised or when you are angry your
blood pressure rises, when you are asleep or resting then your blood
White coat hypertension and the white coat effect are caused by
anxiety, when your body stimulates your ‘fight or flight’
response. Many people are aware that they feel nervous or anxious.
Being relaxed, in a quiet environment and being given reassurance
can help to reduce this effect.
Do I have white coat hypertension?
There are no symptoms of white coat hypertension; you won’t
feel unwell if you have it.
If your high blood pressure has been diagnosed from a small number
of readings (unless the blood pressure is very high) then it is
possible that white coat hypertension could be a factor. A diagnosis
of high blood pressure should be made after a series of readings,
over a period of time, to take into account the possibility of white
The only way to find out if you are affected is to have your blood
pressure measured outside your doctor’s surgery or clinic.
There are two ways of doing this - taking readings yourself at home
and or Ambulatory Blood Pressure Measurement (ABPM) - sometimes
also called 24-hour monitoring
A few people will be asked to have ABPM, which is a test to see
what your blood pressure is like over a period of 24-hours. A small
portable monitor takes readings regularly and automatically over
a day and a night. Your doctor can then look at an average of the
daytime readings and this should show whether you have a normal
blood pressure at home.
You may also be asked to use an automatic or a semi-automatic blood
pressure machine to take a series of readings yourself at home.
Some doctors and clinics will lend you a monitor, usually for two
weeks, and ask you to take readings at certain times of the day.
After you have taken these readings your doctor or nurse will analyse
them and work out an average. You can also buy a blood
pressure monitor to use at home, to monitor your blood pressure
levels. See also Measuring your blood
pressure to make sure you are using the equipment properly to
get accurate readings
What if I have white coat hypertension?
Doctors believe that if you have white coat hypertension you are
at less risk of heart disease or stroke than someone who has sustained
high blood pressure, but at a greater risk than someone who has
normal blood pressure at all times. For this reason it is important
to make sure that you have your blood pressure checked regularly.
This is to make sure that if your blood pressure does start to rise,
you can take steps to lower it as soon as possible.
Finding out whether you may have white coat hypertension is important
as it can make the difference between being treated, or not, and
can affect other aspects of your life such as insurance and work.
If you are concerned, talk to your doctor or nurse.