High blood pressure is a blood
pressure reading of 140/90 mmHg or higher. Both numbers are
important. Nearly one in three 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:
The heart to get larger, which may lead to
heart failure. Small bulges (aneurysms) to form in blood vessels.
Common locations are the main artery from the heart (aorta),
arteries in the brain, legs, and intestines, and the artery leading
to the spleen. Blood vessels in the kidney to narrow, which may
cause kidney failure.
Arteries throughout the body to "harden"
faster, especially those in the heart, brain, kidneys, and legs.
This can cause a heart attack, stroke, kidney failure, or amputation
of part of the leg. 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."
"Normal" blood pressures are lower than 120/80.
"Prehypertension" is blood pressure between 120
and 139 for the top number, or between 80 and 89 for the bottom
number. For example, blood pressure readings of 138/82, 128/89, or
130/86 are all in the "prehypertension" range. If your blood
pressure is in the prehypertension range, it is more likely that you
will end up with high blood pressure unless you take action to
prevent it.
WHAT IS
HIGH BLOOD PRESSURE?
A blood pressure of 140/90 or higher is considered high blood
pressure. Both numbers are important. If one or both numbers are
usually high, you have high blood pressure. If you are being treated
for high blood pressure, you still have high blood pressure even if
you have repeated readings in the normal range.
There are two levels of high blood pressure: Stage 1 and Stage 2
(see the chart below).
Categories for Blood Pressure Levels in Adults*
(In mmHg, millimeters of mercury)
Category
Systolic
(Top number)
Diastolic
(Bottom number)
Normal
Less than 120
Less than 80
Prehypertension
120-139
80-89
High Blood Pressure
Systolic
Diastolic
Stage 1
140-159
90-99
Stage 2
160 or higher
100 or higher
* For adults 18 and older who:
Are not on medicine for high blood pressure
Are not having a short-term serious illness
Do not have other conditions such as diabetes
and kidney disease
Note: When systolic and diastolic blood pressures fall into
different categories, the higher category should be used to classify
blood pressure level. For example, 160/80 would be stage 2 high
blood pressure.
There is an exception to the above definition of high blood
pressure. A blood pressure of 130/80 or higher is considered high
blood pressure in persons with diabetes and chronic kidney disease.
OTHER
NAMES
General
HBP
Hypertension
HTN
Caused by another
condition
Secondary hypertension
Other
Essential hypertension
Primary hypertension
Idiopathic hypertension
WHAT
CAUSE 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?
About 65 million American adults--nearly 1 in 3--have high blood
pressure.
In the U.S., high blood pressure occurs more often in African
Americans. Compared to other groups, blacks:
Tend to get high blood pressure earlier in
life
Usually have more severe high blood
pressures
Have a higher death rate from stroke, heart
disease, and kidney failure.
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:
Are overweight
Are a man over the age of 45
Are a woman over the age of 55
Have a family history of high blood
pressure
Have a "prehypertension (120-139/80-89)"
Other things that can raise blood pressure
include:
Eating too much salt
Drinking too much alcohol
Not eating enough potassium
Not exercising
Taking certain medicines
Stress that is long-lasting
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
YOUR 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:
Do not drink coffee or smoke cigarettes 30
minutes before having your blood pressure taken.
Wear short sleeves.
Go to the bathroom before the reading.
Having a full bladder can change your blood pressure reading.
Sit for 5 minutes before the test.
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:
Sit with your back supported and your feet
flat on the floor.
Rest your arm on a table at the level of
your heart.
Take two readings, at least 2 minutes
apart, and average the results.
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:
Keeping a healthy weight
Being physically active
Following a healthy eating plan that emphasizes
fruits, vegetables, and low-fat dairy foods. Also see the DASH diet
Choosing and preparing foods with less salt and
sodium
Drinking alcohol in moderation if you drink.
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:
Eating healthy foods that include fruits,
vegetables, and low-fat dairy products
Cutting down on salt and sodium in the diet
Losing excess weight and staying at a healthy
weight
Staying physically active (for example, walking
30 minutes a day)
Limiting alcohol intake.
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:
Diuretics are sometimes called "water pills."
They work by helping your kidneys flush excess water and salt from
your body. This reduces the amount of fluid in your blood, and your
blood pressure goes down. There are different types of diuretics.
They are often used along with other high blood pressure medicines
and may be combined with another medicine in one pill.
Beta blockers help your heart beat slower and
with less force. Your heart pumps less blood through the blood
vessels, and your blood pressure goes down.
Angiotensin converting enzyme (ACE) inhibitors
keep your body from making a hormone called angiotensin II, which
normally causes blood vessels to narrow. ACE inhibitors prevents
this narrowing so your blood pressure goes down.
Angiotensin II Receptor Blockers (ARBS) are
newer blood pressure drugs that protect your blood vessels from
angiotensin II. As a result, the blood vessels relax and become
wider, and your blood pressure goes down.
Calcium channel blockers (CCBs) keep calcium
from entering the muscle cells of your heart and blood vessels. This
causes blood vessels to relax, and your blood pressure goes down.
Alpha blockers reduce nerve impulses that
tighten blood vessels, allowing blood to pass more easily and
causing blood pressure to go down.
Alpha-beta blockers reduce nerve impulses to
blood vessels the same way alpha blockers do, but they also slow the
heartbeat, as beta blockers do. As a result, blood pressure goes
down.
Nervous system inhibitors relax blood vessels
by controlling nerve impulses from the brain. This causes blood
vessels to become wider and blood pressure to go down.
Vasodilators open blood vessels by directly
relaxing the muscle in the vessel walls, causing blood pressure to
go down.
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:
Keep track of your blood pressure. Learn to
take your own blood pressure at home or have it regularly checked by
a health care professional. Write it down each time (with date).
Talk to your health care provider about the
names and dosages of your blood pressure medicines and how to take
them.
If you think you're having other problems (side
effects) from taking your medicine, talk to your doctor. Another
medicine may be better for you, or the problem may not be related to
the medicine.
Refill your blood pressure medicines before
they run out.
Take your blood pressure medicines exactly as
directed.
Keep your followup appointments with your
health care provider.
Choose healthier habits--for example, eat a
heart healthy diet, exercise regularly, and don't smoke.
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.
Women and High Blood Pressure
In some women, blood pressure can increase if they use birth control
pills, become pregnant, or take hormone therapy during menopause.
Pregnancy
Many pregnant women with high blood pressure have healthy babies.
However, high blood pressure can be dangerous for both the mother
and the baby. High blood pressure can harm the mother's kidneys and
other organs, and it can cause low birth weight and early delivery.
If you are thinking about having a baby and you have high blood
pressure, talk first to your doctor or nurse. You can take steps to
control your blood pressure before and during pregnancy. Regular
prenatal care (health care during pregnancy) is very important for
your and your baby's health.
Before becoming pregnant:
Be sure your blood pressure is under control.
Making changes such as limiting the salt and sodium in your diet,
exercising regularly, and losing weight if you are overweight can be
helpful.
Discuss with your doctor how high blood
pressure might affect you and your baby during pregnancy, and what
you can do to prevent or lessen problems.
If you take medicines for your blood pressure,
ask your doctor what you should do about taking them during
pregnancy. Women who take ACE inhibitors should talk to their doctor
before they become pregnant.
While you are pregnant:
Be sure to get regular prenatal health care.
Don't miss any appointments.
Don't drink alcohol or smoke.
Talk to your doctor about any over-the-counter
or prescribed medicines you are taking or are thinking about taking.
Some women develop high blood pressure for the
first time in the middle of their pregnancy. In the most serious
cases, the mother develops a condition called preeclampsia or
"toxemia of pregnancy." This condition can threaten the lives of
both the mother and the unborn child.
Even though high blood pressure during pregnancy can be serious,
most women with high blood pressure and those who develop
preeclampsia have successful pregnancies. Getting early and regular
prenatal care is the most important thing you can do for you and
your baby.
Oral Contraceptives (Birth Control Pills)
Women taking birth control pills usually have a small increase in
both systolic and diastolic blood pressure. If you have high blood
pressure and are using birth control pills, get your blood pressure
checked regularly and talk to your doctor about a possible rise in
blood pressure and what you can do about it.
If you have high blood pressure, are age 35 or older, and also
smoke, you should not take birth control pills unless you quit
smoking. Women age 35 and older who smoke and use birth control
pills are more likely to develop heart disease or have a stroke.
High blood pressure also raises your chances of stroke and heart
disease.
If you are age 35 or older, are healthy, do not smoke, and your high
blood pressure is controlled, it may be safe for you to use birth
control pills. Ask your doctor if birth control pills are safe for
you.
Hormone Therapy (HT) for Menopause
A recent study indicated that blood pressure does not increase
significantly with HT in most women with and without high blood
pressure. However, a few women may have a rise in blood pressure due
to estrogen therapy.
If you start taking HT, you should have your blood pressure checked
regularly. Your doctor can help answer your questions.
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
What is normal blood pressure? ANS: A blood pressure reading
below 120/80 is considered normal. In general, lower is better.
If my blood pressure is in the "prehypertension" category, what
should I do? ANS: You should talk to your doctor or other health care provider about
your blood pressure and what you can do to lower it. You may be able
to lower your blood pressure by making changes in your diet, losing
weight, exercising more often, or drinking less alcohol. You have "prehypertension"
blood pressure when your systolic pressure is usually 120 to 139, or
your diastolic pressure is usually 80 to 89.
Can drinking alcohol raise blood pressure?
ANS: Drinking too much alcohol can raise blood pressure. If you drink
alcohol, limit your drinks to just two a day for men and one a day
for women. One drink is 12 ounces of beer, 5 ounces of wine, or 1½
ounces of 80-proof whiskey.
Do children ever get high blood pressure?
ANS: Yes. However, high blood pressure is not as common in children as it
is in adults. High blood pressure in younger children is often
related to another health problem. Children with a family history of
high blood pressure or who are overweight are more likely to develop
high blood pressure.
Is salt and sodium the same thing? ANS: The chemical name for salt is sodium chloride, so salt is partly
sodium. Salt and other forms of sodium are found in many foods. Most
Americans eat too much salt and sodium, and for many, that means
higher blood pressure. Eating less salt and sodium in your diet can
help lower your high blood pressure. Many snack foods, soups,
lunchmeats, and other foods have a lot of sodium in them. Look at
food labels to find products that are lower in sodium.
How do I know if I'm overweight? ANS: Body mass index (BMI) is an easy way to find out if you are
overweight or obese. BMI is calculated by relating how much you
weigh to how tall you are. It gives an approximation of total body
fat. As BMI goes up, so does your chance of getting high blood
pressure, heart disease, and other diseases related to being
overweight. Overweight is defined as a BMI of 25 to 29.9; obesity is
defined as a BMI equal to or more than 30