High Blood Pressure

An Introduction to High Blood Pressure

Blood pressure is a measure of the pressure inside your blood vessels -- both while the heart is beating and while it is relaxed. High blood pressure, as you might guess, is when the pressure within your blood vessels is too high. This is also known as hypertension.

 

About 65 million American adults -- nearly 1 in 3 -- have high blood pressure.

 

Why Is Blood Pressure Important?

Blood pressure is the amount of force (pressure) that blood exerts on the walls of the vessels as it passes through them. As blood is pumped from your heart into your blood vessels, enough pressure is created to send it to all other parts of your body. As vessels travel away from the heart, they branch off and gradually get smaller, just like the branches of a tree. One branch may go to the brain, while another may go to your kidneys. Blood pressure keeps the blood flowing through all these branches so that your body's cells get the oxygen and nutrients they need and waste matter can be removed.

 

Causes of High Blood Pressure

In most people, the specific cause or causes of high blood pressure are not known. This is called primary or essential hypertension. In other people, the condition is the result of another medical problem or medication. When the cause is known, this is called secondary high blood pressure or secondary hypertension.

 

If a person is diagnosed with high blood pressure, it doesn't mean that he or she is "too nervous," overanxious, or obsessive. This is a popular myth. High blood pressure is not nervous tension. In fact, many people who are perfectly calm have the condition.

 

Risk Factors for High Blood Pressure

While for most people there is no known cause of high blood pressure, there are factors that can increase a person's chance of developing it. Some of these risk factors cannot be controlled, including:

 

However, some risk factors can be controlled, including:

 

Symptoms of High Blood Pressure

Most people with high blood pressure don't have any symptoms. This is because the condition doesn't cause problems over a day or weeks, or even months. It usually takes several years for high blood pressure to cause noticeable symptoms, and even when it does cause problems, the symptoms are often mild and nonspecific (meaning they could be caused by several different conditions). For this reason, high blood pressure is often referred to as "the silent killer." People with the condition typically don't even realize they have it until they have blood pressure readings that are too high.

 

 

Testing for High Blood Pressure

Having a blood pressure test is quick and painless. It involves using either a sphygmomanometer or blood pressure machine to measure the blood pressure. Blood pressure is measured in millimeters of mercury (mmHg) and recorded as two numbers: systolic pressure "over" diastolic pressure. For example, the doctor or nurse might say "130 over 80" as a blood pressure reading. This is written as 130/80. Many people define normal blood pressure as an average reading of 120/80 or below.

 

Both numbers in a blood pressure reading are important. As we grow older, systolic blood pressure is especially important.

 

Diagnosing High Blood Pressure

High blood pressure can only be diagnosed after taking several readings to find your average blood pressure. To determine your average blood pressure, your blood pressure needs to be taken two or more times, and each reading must be from a different day. If the average of these readings is more than 140/90, you have high blood pressure.

 

A single reading that is more than 140/90 doesn't necessarily mean that you have high blood pressure; however, your healthcare provider will probably want to monitor your blood pressure over time to see if it stays there. You can also have high blood pressure if the average of only one of the numbers (systolic or diastolic) is too high.

 

Effects of High Blood Pressure

The body structures that chronic (long-term) high blood pressure affects most include the:

 

Because of the effects of high blood pressure on these vital organs, a person who has had it for a long time (known as chronic hypertension) can have:

 

Treating High Blood Pressure

Hypertension research scientists have found certain lifestyle changes that can lower blood pressure. If lifestyle changes alone cannot lower blood pressure to a "normal" level, blood pressure medication can be prescribed.

 

Lifestyle changes are the first form of high blood pressure treatment. They usually help improve a person's quality of life as well. It may take three to six months before your healthcare provider sees the full benefit of lifestyle changes in your condition. Some of these changes may include:

 

Other lifestyle factors that may influence blood pressure and that should be reduced or stopped completely include smoking and prolonged stress (see Smoking and High Blood Pressure or Stress and High Blood Pressure).

 

By lowering blood pressure, people can reduce the long-term effects of hypertension, including heart attacks, stroke, and kidney failure.

 

Types of High Blood Pressure

There are a number of different categories of high blood pressure. Most people have what is known as essential hypertension or primary hypertension. This is high blood pressure where the cause is not known. Other types include:

 

There are several types of high blood pressure in pregnancy. These types include:

 

High Blood Pressure: Looking Ahead

Many people do not have symptoms of high blood pressure or discomfort, so they find it easy to ignore their condition. However, this significantly increases the chances of having:

 

Getting the condition under control may add years to a person's life. Healthy lifestyle changes often improve both a person's high blood pressure and his or her quality of life.