High blood pressure

High blood pressure or hypertension means high pressure (tension) in the arteries. The arteries are the vessels that carry blood from the pumping heart to all of the tissues and organs of the body. High blood pressure does not mean excessive emotional tension, although emotional tension and stress can temporarily increase the blood pressure. Normal blood pressure is below 120/80; blood pressure between 120/80 and 139/89 is called “pre-hypertension”, and a blood pressure of 140/90 or above is considered high blood pressure. The systolic blood pressure, which is the top number, represents the pressure in the arteries as the heart contracts and pumps blood into the arteries. The diastolic pressure, which is the bottom number, represents the pressure in the arteries as the heart relaxes after the contraction. The diastolic pressure, therefore, reflects the minimum pressure to which the arteries are exposed.

Many people may not view high blood pressure as life-threatening. But uncontrolled high blood pressure can increase your risk of serious health problems. Fortunately, high blood pressure can be detected with a simple test — and once you know you have high blood pressure, you can work with your doctor to control it.

Signs and Symptoms

Most people with high blood pressure have no signs or symptoms, but people often think that headaches, dizziness or nosebleeds are common warning signs and symptoms of high blood pressure. It's true that a few people with early-stage high blood pressure have a dull ache in the back of their heads when they wake in the morning. Or perhaps they have a few more nosebleeds than normal.

Headaches, dizziness or nosebleeds typically don't occur until high blood pressure has reached a more advanced stage — one that's possibly life-threatening. Even so, most people with the highest blood pressure readings don't experience any of these symptoms.

Other signs and symptoms sometimes associated with high blood pressure generally are caused by other conditions that can lead to high blood pressure. Such signs and symptoms include:

• Excessive perspiration
• Muscle cramps
• Weakness
• Frequent urination
• Rapid or irregular heartbeat (palpitations)
  

More about High blood pressure

Causes

The more blood your heart pumps and the narrower your arteries, the higher your blood pressure. A blood pressure reading consists of two numbers:

The top number indicates systolic pressure. This is the amount of pressure your heart generates when pumping blood out through your arteries.
The bottom number indicates diastolic pressure. This is the amount of pressure in your arteries when your heart is at rest between beats.
The most recent guidelines for high blood pressure were issued in the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure (JNC) and published in the Journal of the American Medical Association in May 2003. The JNC represents a coalition of leaders from 46 professional, public, voluntary and federal health care agencies, including the American College of Cardiology, the American Diabetes Association, the American Heart Association, the American Public Health Association, the American Society of Hypertension, and the National Heart, Lung, and Blood Institute. According to these guidelines, blood pressure for adults is classified as follows:

Normal blood pressure. Your blood pressure is normal only if it's below 120/80 millimeters of mercury (mm Hg), but some data indicate that 115/75 mm Hg should be the new gold standard. Once your blood pressure rises above that threshold, your risk of cardiovascular disease may begin to increase.
Prehypertension. Prehypertension is a systolic pressure ranging from 120 to 139 or a diastolic pressure ranging from 80 to 89. If your blood pressure is right at 120/80, you have prehypertension — your blood pressure isn't normal or optimal.
Stage 1 hypertension. This includes a systolic pressure ranging from 140 to 159 or a diastolic pressure ranging from 90 to 99.
Stage 2 hypertension. The most severe hypertension, this includes a systolic pressure of 160 or higher or a diastolic pressure of 100 or higher.
Only one of the numbers — the top or the bottom — needs to be high for you to have prehypertension or hypertension.

In 90 percent to 95 percent of high blood pressure cases, there's no identifiable cause. This type of high blood pressure is called essential hypertension or primary hypertension. It differs from secondary hypertension, in which the increased pressure results from another underlying condition, such as:

• Kidney disease
• Adrenal disease
• Thyroid disease
• Abnormal blood vessels
• Preeclampsia — high blood pressure and protein in the urine after the 20th week of pregnancy
• Sleep apnea
• Certain medications, including birth control pills, cold remedies, decongestants, over-the-counter pain relievers and some prescription drugs, may also cause secondary hypertension.

Although acetaminophen (Tylenol, others) was once considered very safe, researchers reported in September 2005 that regular use of higher doses may increase the risk of secondary hypertension. Researchers studied 5,000 women who didn't have high blood pressure when the studies began. Women who took an average of 500 milligrams or more of acetaminophen daily over several years were more likely to develop high blood pressure than were women who didn't take any acetaminophen. It's not known if the same holds true for men since they weren't included in this study. The women were part of two phases of the Nurses' Health Study, a study of more than 200,000 nurses that began in 1976 and still continues.

Illegal drugs, such as cocaine and amphetamines, can also increase blood pressure.

Secondary hypertension may have a more rapid onset and cause higher blood pressure than does primary hypertension, which tends to develop gradually over many years.

Risk Factors

• Family history of hypertension
• Alcohol abuse
• High sodium intake
• Inactive lifestyle
• Being overweight
• Mood disorders, particularly depression and anxiety (they may have a direct impact on blood vessels or they may lead to unhealthy behaviors such as alcohol and substance abuse or poor weight management)

Hypertension is more common among African Americans than Whites (this may be due to nitric oxide levels or to social factors such as chronic life stressors)

Diagnosis
Blood pressure is the force of the blood pushing against the walls of the arteries. Each time the heart beats, or contracts, it pumps blood into the arteries. Blood pressure is at its maximum at this time; this is known as the systolic blood pressure. When the heart is at rest, between beats, the blood pressure falls; this is known as the diastolic pressure. A person with hypertension has an average systolic blood pressure above 140 mm Hg and/or a diastolic blood pressure above 90 mm Hg (usually written as 140/90).
To diagnose hypertension, a physician will obtain a blood pressure measurement during a routine physical examination.Treatment Approach

The goal of treatment is to prevent health complications that may occur as a result of high blood pressure. Your doctor also may suggest steps to control disorders such as diabetes and high blood cholesterol, which may contribute to high blood pressure or may occur along with high blood pressure. Treating conditions such as diabetes and high blood cholesterol will reduce your risk of heart attack and stroke beyond the benefits accrued by lowering blood pressure.
Blood pressure goals aren't the same for everyone. Although everyone should strive to reach blood pressure readings of below 140/90, doctors recommend lower readings for people with certain conditions. The goal is 130/80 if you have or have had chronic kidney disease or diabetes.

The safest way to control your blood pressure is to change your lifestyle. But sometimes lifestyle changes alone can't reduce your blood pressure enough. You may also have to treat another medical condition besides high blood pressure. In these cases, you may need medication. Discuss with your doctor the goals of treatment and the roles that both lifestyle changes and medications can play. Maintaining lifestyle changes may improve the effectiveness of the medications you're taking and may mean you'll need fewer drugs or lower dosages.
Many types of medications to lower blood pressure are available. They lower your blood pressure in different ways. If one medication doesn't decrease your blood pressure to a safe level, your doctor may substitute another one or add one to your regimen.

The major types of medication used to control high blood pressure include:
Diuretics. These medications act on your kidneys to help your body eliminate sodium and water, reducing blood volume. Diuretics are often the first — but not the only — choice in treatment because they're often the most effective.
Beta blockers. These medications block the effects of certain adrenaline-related chemicals, causing your heart to beat more slowly and less forcefully.
Angiotensin-converting enzyme (ACE) inhibitors. These medications help relax blood vessels by blocking the formation of a naturally occurring chemical that narrows blood vessels. These medications are especially important in treating high blood pressure in people with coronary heart disease, heart failure or kidney failure.
Angiotensin II receptor blockers. These medications help relax blood vessels by blocking the action — not the formation — of a naturally occurring chemical that narrows blood vessels.
Calcium antagonists, also known as calcium channel blockers (CCBs). These medications help relax the muscles of blood vessels. Some slow your heart rate. A word of caution, though: If you take certain calcium antagonists, don't eat grapefruit or drink grapefruit juice. Grapefruit juice interacts with some calcium antagonists, causing blood levels of the medication to rise and putting you at a higher risk of side effects from the drug. This action of the juice may persist for 24 hours. If you're concerned about interactions, talk to your doctor or pharmacist.

To achieve a blood pressure goal, your doctor may recommend the use of multiple drugs. In fact, low-dose medications in combination can lower blood pressure as well as can larger doses of one drug. This strategy may reduce the number of doses you need a day, which can reduce side effects. Most people can control their blood pressure with long-acting drugs, so the medications need to be taken only once or twice daily. Your doctor may suggest you take aspirin once your blood pressure is under control in order to reduce your risk of cardiovascular disorders.

Other drug classes may be used in addition to combinations of the above medications, when blood pressure hasn't reached a set goal. These drug classes may include:
Alpha blockers. These medications prevent muscle contractions in smaller arteries and reduce the effects of naturally occurring body chemicals that narrow blood vessels.
Central-acting agents. These medications prevent your brain from signaling your nervous system to increase your heart rate and narrow your blood vessels.
Direct vasodilators. These medications work directly on the muscles in the walls of your arteries, preventing the muscles from tightening and your arteries from narrowing.

Medications

High blood pressure Medications

• Accupril
• Adalat
• Atacand
• Avapro
• Benace
• Benazepril
• Catapress
• Cozaar
• Diovan
• Diovan-HCTZ
• Ibesartan
• Lisinopril
• Lisinopril HCTZ
• Lopresor-SR
• Lotensin
• Micardis
• Micardis-Plus
• Norvasc