High blood pressure

WEB EXCLUSIVE / JULY 2005
POSTGRADUATE MEDICINE
Update of a handout originally published in October 1996

Download this Patient Note in PDF format

High blood pressure, which is also called hypertension, is a lifelong disorder that requires continuous monitoring and management. A common disorder, it affects about one in four adults in the United States. The good news is that it can be controlled with diet, lifestyle changes and, if needed, drugs.

What is high blood pressure?
High blood pressure consists of multiple blood pressure readings of 140/90 mm Hg or higher. The average blood pressure of a healthy adult is less than 120/80 (expressed as "120 over 80") mm Hg (millimeters of mercury). The first number (the systolic reading) represents the amount of pressure in your arteries when the heart beats. The second number (the diastolic reading) is the amount of pressure in your arteries when your heart rests between beats. People who consistently have a systolic reading between 120 and 139 or a diastolic reading between 80 and 89 are considered to have a condition called prehypertension, which means they are likely to have high blood pressure in the future.

Some people have high blood pressure readings at the doctor's office because they are nervous, a condition known as white-coat syndrome. Checking your blood pressure at home or wearing a device that tracks your blood pressure for 24 hours can help you get more accurate readings.

What causes high blood pressure?
The amount of blood pumped by the heart and the size and condition of the arteries determine blood pressure. When high blood pressure is caused by another disorder (for example, heart or kidney disease, sleep apnea, thyroid disease, or obesity) or use of certain drugs (for example, oral contraceptives), it is called secondary hypertension. In 95% of cases, the cause is unknown, and the condition is called essential hypertension.

Obesity, lack of regular exercise, smoking, and a high-fat, high-salt diet can contribute to high blood pressure. Likewise, so can both a family history of high blood pressure and levels of hormones in the bloodstream.

Why is high blood pressure dangerous?
Untreated high blood pressure can lead to heart disease, blood vessel damage (arteriosclerosis) and, eventually, heart attack or heart failure. It can also result in stroke, kidney failure, brain damage, or loss of vision. When high blood pressure is present in combination with abdominal obesity and high levels of cholesterol and blood sugar, the risk of heart disease is higher than when any of these conditions occurs alone.

What are the symptoms of high blood pressure?
High blood pressure is called a silent disease, because in most cases there are no symptoms. If symptoms are present, they may include headache or dizziness.

How is high blood pressure treated?
The goal is to reduce blood pressure to below 140/80 or, in people with chronic kidney disease or diabetes, below 130/80. Your doctor may prescribe weight loss, exercise, dietary changes, or drugs such as a diuretic (water pill), beta blocker, angiotensin-converting enzyme (ACE) inhibitor, angiotensin II receptor blocker (ARB), or calcium channel blocker. If your blood pressure is very high, more than one type may be needed.

How can I help manage my blood pressure?
If you have high blood pressure or prehypertension, there are a number of steps you can take to help control your blood pressure.

• Have your blood pressure checked as often as your doctor recommends. A home blood pressure monitor may be an option.
• Quit smoking.
• Achieve and maintain a healthy body weight.
• Eat a low-fat, high-fiber diet that emphasizes fresh fruits, vegetables, and whole grains and minimizes red meat and high-fat dairy products.
• Avoid using salt in cooking, and check the nutrition labels on prepared foods for salt content. Products labeled as low in salt (sodium) are preferable. Even baking soda contains sodium.
• Don't drink alcohol, or if you do, drink in moderation. Moderate consumption is considered to be no more than one drink a day for women and no more than two drinks a day for men.
• Get 40 minutes of moderate to vigorous exercise each day. Choose activities you enjoy. For added benefit, exercise more.
• Minimize use of nonsteroidal anti-inflammatory drugs (for example, ibuprofen) and decongestant nasal sprays, which can raise blood pressure.
• Take your medications exactly as they are prescribed.
• Call your doctor immediately if you feel unusually tired or confused, notice blood in your urine, or have changes in vision, a nosebleed, chest pain, excessive sweating, or an irregular heartbeat.

For more information American Society of Hypertension 148 Madison Ave, 5th Floor New York, NY 10016 212-696-9099 http://www.ash-us.org MEDLINEplus http://www.nlm.nih.gov/medlineplus/ency/article/000468.shtml National Heart, Lung, and Blood Institute Health Information Center PO Box 30105 Bethesda, MD 20824 301-592-8573 http://www.nhlbi.nih.gov/hbp/index.shtml

This information is not a substitute for medical treatment.

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