Hypertension or High Blood Pressure , is a medical condition in which narrowed arteries cause persistently elevated pressure of blood within the arteries, which carry blood from the heart through the body. The heart must work harder to pump blood through the narrowed arteries. If the condition persists, damage to the heart and blood vessels is likely, increasing the risk for stroke, heart attack, and kidney or heart failure. Often called the “silent killer,” hypertension usually causes no symptoms until it reaches a life-threatening stage.

Physicians use two measurements to describe blood pressure. Systolic pressure measures blood pressure as the heart contracts to pump out blood. Diastolic pressure measures blood pressure as the heart relaxes to allow blood to flow into the heart. An instrument called a sphygmomanometer measures systolic and diastolic pressure using units of millimeters of mercury (abbreviated mm Hg).

Blood pressure is classified in four categories: normal, prehypertension, stage 1 hypertension, and stage 2 hypertension.

•  Stage 1 hypertension is defined as a systolic pressure of 140 to 159 mm Hg or a diastolic pressure of 90 to 99 mm Hg.

•  Stage 2 hypertension is defined as 160/100 mm Hg or higher.

Causes

Although many people believe that hypertension is caused by extreme activity or tension, this theory has not been proved.

When no underlying cause of hypertension is discovered, the disease is called primary, or essential, hypertension. If another disease, such as kidney or endocrine disease, causes the elevated blood pressure, the condition is called secondary hypertension.

Symptoms

Hypertension has been called the silent disease because it often has no obvious symptoms. A person can have high blood pressure for years without noticing any symptoms. Symptoms include headache, fatigue, dizziness, flushing of the face, ringing in the ears, and frequent nosebleeds. However, these symptoms may also result from other conditions.

Treatment

Physicians recommend that people with pre-hypertension undergo diet and lifestyle changes, such as losing weight and quitting smoking, in order to prevent a rise in blood pressure. Some patients can lower their blood pressure by limiting salt in their diet. Increasing physical activity and reducing alcohol consumption to less than two drinks per day for men and one drink per day for women may also lower blood pressure.

For those with stage 1 and stage 2 hypertension, a physician may prescribe diet and lifestyle changes, as well as a regular exercise program, and strict limitation of sodium intake, which affects fluid balance and volume and therefore blood pressure. Controlling sodium in the diet requires restriction of table salt as well as careful scrutiny of all food and drug labels. If medication is indicated, a physician may prescribe one or several drugs. Commonly prescribed drugs include diuretics, angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, and calcium channel blockers.