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 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?
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 enou