The Dangers of Hypertension -
The Silent Killer
By Joseph Weisstuch

NEW YORK (AP) -- Hypertension, known as the "silent disease," can be compared to what happens when too much air is pumped into a tire. Too high pressure will damage the tire. Eventually, untreated high blood pressure can damage the body's vascular system.
Hypertension, or high blood pressure, afflicts about 50 million Americans. Left untreated, it can lead to a heart attack, a stroke, circulatory problems and other health complications.
The condition is called the "silent" disease because there are no noticeable symptoms in 95 percent of cases. The problem is usually discovered during a routine office visit or when severe symptoms, including dizziness, headache or breathing difficulty occur.
Contrary to popular belief, high blood pressure is not caused by tension or stress, though these factors may produce a temporary rise in blood pressure. Factors that may influence increased blood pressure may include age, weight, diet, smoking, heredity and an underlying illness.
Normal blood pressure is about 120 over 80. The first number represents systolic pressure, the peak pressure at the moment the heart contracts and pumps blood into the arteries. The lower number is diastolic pressure, the lowest pressure in the arteries just before the next contraction of the heart.
Whether blood pressure is considered high is somewhat arbitrary and varies from individual to individual, and the diagnosis of hypertension requires the judgment of a physician.
For example, if a person over the age of 65 has a blood pressure reading of 140 over 90, a physician might consider the reading normal since blood pressure tends to rise with age. But if that same person had a blood pressure reading of 150 over 110, there would be a cause for concern. Blood pressure readings above 140 over 90 are considered too high. In general, the higher the reading, the more severe the disease is considered.
Patients with hypertension can be categorized according to the cause of their hypertension: essential, or primary, hypertension for which there is no apparent cause; and secondary hypertension, which is related to an underlying disorder such as kidney disease or a hormonal imbalance.
In many cases, essential hypertension, which accounts for 95 percent of patients with high blood pressure, is believed to be linked to heredity and general health habits, including excess weight, smoking and lack of exercise. In those genetically susceptible, a high intake of sodium in the diet may contribute to hypertension.
The first sign of essential hypertension -- in most cases, discovered by a routine blood pressure check -- is usually found in people in their 40s and 50s. In the elderly without a previous history of hypertension, the cause may be due to an underlying vascular problem.
Without treatment, blood pressure in a person with a history of essential hypertension will continue to rise over the years. In some people, blood pressure may rise suddenly to high levels which constitutes a condition known as malignant hypertension. If the elevated blood pressure is not brought under control, it can be followed quickly by stroke, kidney or heart failure.
Treatment for hypertension may include lifestyle changes, prescribed medications or a combination of both, depending upon the severity of the condition. Non-pharmacological treatment for patients considered "borderline" would include exercise, losing excessive weight and cutting back on alcohol, caffeine and salt.
If blood pressure remains too high, medications, such as a thiazide diuretic, beta-blocker, ACE-inhibitor or long-acting calcium channel blocker may be prescribed. Although such drugs can control high blood pressure, they do not cure it and patients generally must continue to take medications for the rest of their lives.
For elderly patients, walking exercises and a reduced salt intake can be of great benefit in conjunction with prescribed medications.
Research over the last five years has shown that patients who are treated with medication and who manage to change their lifestyle (more exercise, weight loss and healthier diets) have a much lower incidence of stroke and heart disease. Anyone over the age of 40 who is overweight and has a family history of hypertension should consider seeing their doctor for a blood pressure check at least twice a year.
Dr. JOSEPH WEISSTUCH is a clinical assistant professor of medicine at New York University School of Medicine.