Understanding

Main information about blood pressure
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WHAT IS BLOOD PRESSURE ?

The heart is a very important organ that is responsible for ensuring that blood is moved around the body. Thanks to the heart, oxygen and nutrients are delivered to every tissue and organ in your body. In order to make this delivery possible, the heart has to generate a force to pump blood around your body. The force the heart generates to make blood run through your arteries is called BLOOD PRESSURE.

A person’s blood pressure is typically expressed as two numbers:

The ideal blood pressure for a healthy adult is < 120/80 mm Hg.
Blood pressure can also be read in centimeters of mercury : 12/8 cm Hg. 2013 ESH/ESC guidelines for the management of arterial hypertension

HOW TO MEASURE BLOOD PRESSURE

Most of the time, it is your doctor or a nurse who will measure your blood pressure, for example, during a routine visit. To do so, they will use a sphygmomanometer. It is a pressure-measuring device (manometer) connected to an inflatable cuff that is wrapped around your upper arm. The doctor will inflate the cuff, and you will feel your arm being squeezed quite hard. The air in the cuff is then let out slowly, and you will feel the grip of the cuff lessen. Blood pressure can then be measured with the manometer (in millimeters of mercury [mm Hg]).

Two different sphygmomanometers exist:

A MANUAL ONE
The doctor or nurse inflates the cuff using a hand pump and then uses a stethoscope to listen to your pulse.

A DIGITAL ONE
The cuff inflates and deflates automatically.
The pulse is detected by a sensor inside the device.

To get an accurate measurement of your blood pressure, when a measurement is taken you should have rested for at least five minutes previously and be seated and silent, ie, not talking.

WHAT IS HYPERTENSION ?

Blood pressure can be high, normal, or low, but over time and with age, blood pressure rises. Why ? The walls of large arteries become more rigid and the small blood vessels become narrower. Because of these changes, the heart has to generate a greater force to keep blood flowing around the body. This leads to an increase in blood pressure. Hypertension is defined as blood pressure that is consistently higher than 140/90 mm Hg (systolic, diastolic, or both blood pressures).

What do my numbers mean ?

Optimal
Systolic < 120 and Diastolic < 80
Normal
Systolic 120-129 and/or Diastolic 80-84
“It is ok, keep going !”
High
normal
Systolic 130-139 and/or Diastolic 85-89
“Your BP needs to be checked more often and you should follow lifestyle advice”.
Grade 1
hypertension
Systolic 140-159 and/or Diastolic 90-99
Grade 2
hypertension
Systolic 160-179 and/or Diastolic 100-109
Grade 3
hypertension
Systolic > 180 and/or Diastolic > 110
isolated systolic hypertension
Systolic > 140 and Diastolic < 90
“Your BP needs to be reduced with a medical treatment and you should follow lifestyle advice”.
2013 ESH/ESC guidelines for the management of arterial hypertension

HOW TO DIAGNOSE HYPERTENSION

Hypertension (blood pressure ≥140/90 mm Hg) is a silent disease because there are rarely any obvious symptoms and it frequently goes undiagnosed. Unfortunately, often the first time someone finds out that they have high blood pressure is when they are taken to hospital because high blood pressure has led to a stroke or a heart problem.

For that reason, it is recommended that you get your blood pressure checked every year. It is very easy to measure – don’t hesitate to ask your doctor, your nurse, or even your pharmacist to check your blood pressure.

If your blood pressure reading is 140/90 mm Hg or more, your doctor will probably need to do several checks to confirm the diagnosis of hypertension. He or she could also use an ambulatory blood pressure monitoring device to measure your blood pressure over 24 hours.

WHAT ARE THE CAUSES OF HYPERTENSION ?

There are two types of hypertension: primary (or essential hypertension) and secondary hypertension.

Primary hypertension describes high blood pressure that has no obvious cause. There are a number of factors that can increase the risk of developing high blood pressure:

Smoking
BEING OVERWEIGHT OR OBESE
Physical inactivity
Too much salt
Too much alcohol
Stress
Genetics
Age

Secondary hypertension concerns high blood pressure produced by identifiable causes (for example, an abnormal production of hormones from the adrenal glands). Only a small number of patients suffer from this kind of hypertension. Once the cause is found and treated correctly, blood pressure should return to normal.

HOW CAN HYPERTENSION AFFECT THE BODY ?

When a patient has hypertension, his heart has to work harder to ensure the flow of blood around the body.
Over time, this high pressure can gradually weaken the heart and damage artery walls, leading to changes in blood flow.
All these situations can lead to an increased risk of developing cardiovascular diseases (stroke, heart disease, and heart failure).
Other parts of the body, including the kidneys, limbs, and eyes, may also suffer damage.

WHO ARE THE “BAD FRIENDS” OF HYPERTENSION ?

Sometimes other diseases can worsen or impact a primary disease. These other diseases are what we call comorbid diseases. Hypertension has its own set of “bad friends,” the main ones being:

Hypercholesterolemia :

when there are high levels of LDL-cholesterol in the blood, which are associated with an increased risk of atherosclerosis or coronary heart disease.

Type 2 Diabetes :

occurs when the cells of the body do not respond well to insulin, a hormone controlling blood sugar levels. As a result, blood sugar levels rise. High blood sugar levels over a prolonged period lead to complications such as stroke, foot ulcers, and eye damage.

Coronary artery disease :

a limitation of blood flow to the heart leads to a lack of oxygen for myocardial cells. A common symptom is chest pain, which often occurs during exercise.

Chronic kidney disease :

when over a period of months or years, kidneys do not function properly, leading to complications such as cardiovascular disease, anemia, or pericarditis.

WHAT ARE THE MAIN FIGURES IN HYPERTENSION ?

World Health Organization - Global Health Observatory (GHO) data – Raised blood pressure
J. Kumar, “Epidemiology of hypertension”, Clinical Queries: Nephrology, Volume 2, Issue 2, April– June 2013, Pages 56-61

HYPERTENSION : A WORLDWIDE PROBLEM

Although the proportion of hypertensive patients (prevalence) varies in different parts of the world, every region of the globe is affected.