American Medical Association Family Medical Guide - American Medical Association [332]
High blood pressure is a very common condition, affecting about 50 million adults in the United States. Because it seldom causes symptoms, many people who have high blood pressure do not know that they have it. However, in most cases, high blood pressure is easy for doctors to detect and treat.
The cause of high blood pressure is usually unknown. This is called primary or essential hypertension. Most people who have high blood pressure have essential hypertension. Although essential hypertension can’t be cured, it can be controlled. Hypertension that results from an underlying disease or condition—such as long-term kidney disease, thyroid disease, adrenal gland abnormalities, or use of illicit drugs—is called secondary hypertension. Secondary hypertension can be cured by successfully treating the underlying disease or condition.
In most people who have hypertension, blood pressure continues to rise over time unless it is treated. Sometimes, however, significantly high blood pressure develops very quickly. This life-threatening condition, which can result from either essential hypertension or secondary hypertension, is called malignant hypertension. Untreated malignant hypertension can lead rapidly to stroke, kidney failure, or heart failure.
Risk Factors
Testing Blood Pressure
The Meter
Blood pressure is measured with an instrument called a sphygmomanometer, which consists of an inflatable rubber cuff and a special type of pressure gauge. Because the earliest devices for measuring blood pressure used a mercury-filled glass column, blood pressure is expressed as millimeters of mercury (mm Hg).
Measuring Blood Pressure
To measure your blood pressure, the doctor or nurse wraps the cuff securely around your upper arm and inflates the cuff by squeezing the attached rubber bulb until it is tight enough to stop blood flow temporarily. He or she then begins to gradually deflate the cuff, while listening through a stethoscope placed inside your elbow to the sound of blood flowing through the main artery in your arm. The doctor takes a reading from the meter as soon as he or she hears the first heartbeat. This is the systolic pressure. The doctor continues deflating the cuff until blood flows steadily through the artery. The doctor takes a second reading when he or she hears the last heartbeat. This is the diastolic pressure.
Although the cause of high blood pressure is usually unknown, a number of factors can increase your chances of developing high blood pressure or worsen existing high blood pressure:
• You have close family members (parents or siblings) who have high blood pressure.
• You are male.
• You are female and past menopause.
• You are black.
• You are overweight.
• You do not exercise regularly.
• You use any tobacco products (including smokeless tobacco).
• You regularly consume more than two alcoholic drinks per day.
• You have diabetes or long-term kidney disease.
• You are not able to cope with stress.
Symptoms
In the early stages, high blood pressure usually does not produce symptoms. By the time symptoms such as severe headaches, palpitations (heartbeats that you’re aware of), or shortness of breath occur, the disease has already caused organ damage. Therefore, it is vital to monitor your blood pressure and have it checked every time you visit your doctor, especially if you have any of the risk factors for hypertension described above.
If not treated, high blood pressure can lead to the following health problems, even if you don’t have any symptoms:
• Atherosclerosis Uncontrolled high blood pressure causes the artery walls to thicken and lose elasticity, which promotes formation of hardened fatty deposits