What is blood pressure?

Blood pressure, also known as BP or B/P, is the force exerted by the blood against the walls of the arteries. It is measured in millimeters of mercury (mm Hg). The systolic pressure is the force exerted when the heart contracts and pumps blood into the arteries; the diastolic pressure is the force exerted while the heart relaxes between beats.

Systolic pressure is usually higher than diastolic pressure.

How does it affect you?

High blood pressure is often called hypertension. It can damage your heart and brain and lead to stroke, kidney failure, heart attack, and even blindness. High blood pressure is the leading cause of death in the United States. It affects more than one third of American adults over age 40.

What causes high blood pressure?

There are several factors that contribute to high blood pressure. These include:

How do you know if you have high blood pressure?

Your doctor will check your blood pressure during an office visit. He or she will ask you to sit quietly for at least five minutes. Then your doctor will use a special cuff to measure your blood pressure. You should not feel any pain when the cuff is placed around your upper arm. If you do, your blood pressure reading may be inaccurate.

Blood pressure readings vary from day to day. Therefore, it is important to have several readings taken at different times of the day. The first two readings are called the initial or resting blood pressure. The second two readings are called the daytime or sitting blood pressure. The last two readings are called the night-time or lying down blood pressure.

When should you see your doctor?

If you have high blood pressure, you should see your doctor. This is especially true if you have any of these signs or symptoms: