What Is High Blood Pressure?
High blood pressure is a blood pressure reading of 140/90 mmHg or higher. Both numbers are important.
About one in every four American adults has high blood pressure. Once high blood pressure develops, it usually lasts a lifetime. The good news is that it can be treated and controlled.
High blood pressure is called "the silent killer" because it usually has no symptoms. Some people may not find out they have it until they have trouble with their heart, brain, or kidneys. When high blood pressure is not found and treated, it can cause:i The heart to get larger, which may lead to heart failure.
Blood vessels in the eyes to burst or bleed, which may cause vision changes and can result in blindness.
What is blood pressure?
Blood is carried from the heart to all parts of your body in vessels called arteries. Blood pressure is the force of the blood pushing against the walls of the arteries. Each time the heart beats (about 60-70 times a minute at rest), it pumps out blood into the arteries. Your blood pressure is at its highest when the heart beats, pumping the blood. This is called systolic pressure. When the heart is at rest, between beats, your blood pressure falls. This is the diastolic pressure.
Blood pressure is always given as these two numbers, the systolic and diastolic pressures. Both are important. Usually they are written one above or before the other, such as 120/80 mmHg. The top number is the systolic and the bottom the diastolic. When the two measurements are written down, the systolic pressure is the first or top number, and the diastolic pressure is the second or bottom number (for example, 120/80). If your blood pressure is 120/80, you say that it is "120 over 80."
Blood pressure changes during the day. It is lowest as you sleep and rises when you get up. It also can rise when you are excited, nervous, or active.
Still, for most of your waking hours, your blood pressure stays pretty much the same when you are sitting or standing still. That level should be lower than 120/80. When the level stays high, 140/90 or higher, you have high blood pressure. With high blood pressure, the heart works harder, your arteries take a beating, and your chances of a stroke, heart attack, and kidney problems are greater.
What is normal blood pressure?
A blood pressure reading below 120/80 is considered normal. In general, lower is better.
However, very low blood pressures can sometimes be a cause for concern and should be checked out by a doctor.
Doctors classify blood pressures under 140/90 as either "normal," or "prehypertension."
What Causes High Blood Pressure?
In many people with high blood pressure, a single specific cause is not known. This is called essential or primary high blood pressure. Research is continuing to find causes.
In some people, high blood pressure is the result of another medical problem or medication. When the cause is known, this is called secondary high blood pressure.
Who Gets High Blood Pressure?
More than 50 million American adults--1 in 4--have high blood pressure.
In the U.S., high blood pressure occurs more often in African Americans. Compared to other groups, blacks:
Many people get high blood pressure as they get older. Over half of all Americans age 60 and older have high blood pressure. This is not a part of healthy aging! There are things you can do to help keep your blood pressure normal, such as eating a healthy diet and getting more exercise.
Your chances of getting high blood pressure are also higher if you:
Signs and Symptoms of High Blood Pressure
High blood pressure is called "the silent killer" because you can have it for years without knowing it. The only way to find out if you have high blood pressure is to have your blood pressure measured. Using a blood pressure cuff and stethoscope or electronic sensor, your doctor or nurse can take your blood pressure and tell you if it is high.Even though high blood pressure usually has no signs or symptoms, it is dangerous if it continues over time. It is important to find out if you have high blood pressure and, if so, to keep it under control.
How Do You Know if You Have High Blood Pressure?
Only your doctor can tell you if you have high blood pressure. Most doctors will check your blood pressure several times on different days before deciding that you have high blood pressure. A diagnosis of high blood pressure is given if repeated readings are 140/90 or higher or 130/80 or higher if you have diabetes or chronic kidney disease.
Having your blood pressure tested is quick and easy. Your doctor or nurse will use some type of a gauge, a stethoscope (or electronic sensor), and a blood pressure cuff, also called a sphygmomanometer(sfig-mo-ma-NOM-e-ter).
Blood pressure readings are usually taken when you are sitting or lying down and relaxed. Below are things you can do before going to get your blood pressure taken:
You should ask the doctor or nurse to tell you the blood pressure reading in numbers.
You also can check your blood pressure at home with a home blood pressure measurement device, or monitor. It is important that you understand how to use the monitor properly. Your doctor, nurse, or pharmacist can help you check the monitor and teach you how to use it correctly. You also may ask for their help in choosing the right blood pressure monitor for you. Blood pressure monitors can be bought at discount chain stores and pharmacies. Below are additional things to do when taking your blood pressure at home:
Some people's blood pressure is high only when they visit the doctor's office. This condition is called "white coat" hypertension. If your doctor suspects this, you may be asked to check and record your blood pressure at home with a home monitor. Another way to check blood pressure away from the doctor's office is by using an ambulatory blood pressure monitor. This device is worn for 24 hours and can take blood pressure every 30 minutes.
How Can I Prevent High Blood Pressure?
You can take steps to prevent high blood pressure. These steps include:
How is High Blood Pressure Treated?
Usually, the goal is to keep your blood pressure below 140/90 (130/80 if you have diabetes or chronic kidney disease). Ask your doctor what your blood pressure goal should be.
Some people can prevent or control high blood pressure by changing to healthier habits, such as:
Sometimes blood pressure stays too high even when a person makes these kinds of healthy changes. In that case, it is necessary to add medicine to help lower blood pressure. Medicines will control your blood pressure but they cannot cure it. You will need to take high blood pressure medicine for a long time.
Blood pressure medicines work in different ways to lower blood pressure. Often, two or more drugs work better than one. Some drugs lower blood pressure by removing extra fluid and salt from your body. Others affect blood pressure by slowing down the heartbeat, or by relaxing and widening blood vessels.
Below are the types of medicines used to treat high blood pressure:
It is important that you take your blood pressure medication the same time each day.
Living with High Blood Pressure
If you have high blood pressure, it is important that you:
Remember, high blood pressure has no symptoms. If you have it, you cannot tell by the way you feel when your blood pressure level is high.
Older Adults and High Blood Pressure
A common form of high blood pressure in older adults is isolated systolic hypertension (ISH).
ISH is high blood pressure, but only the top (systolic) number is high (140 or higher). ISH can be as harmful as high blood pressure in which both numbers are high.
ISH is the most common form of high blood pressure for older Americans. About 2 out of 3 people over age 60 with high blood pressure have ISH.
You may have ISH and feel fine. As with other types of high blood pressure, ISH often causes no symptoms. To find out if you have ISH--or any type of high blood pressure--get your blood pressure checked.
If not treated, ISH can cause damage to your arteries and to body organs. ISH is treated the same way as high blood pressure in which both systolic and diastolic pressures are high: by making changes in your health habits and with blood pressure medicines, if needed.
Frequently Asked Questions
Source: National Institutes of Health