Hypertension

Hypertension is defined by the Sixth Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC-VI) as a systolic blood pressure of 140 mmHg or higher, or a diastolic blood pressure of 90 mmHg or higher. Out of office goal blood pressure is less than 135/85. It is estimated that 60% of the U.S. population over age 65 has hypertension .

Hypertension should generally not be diagnosed in a single office visit or by a single isolated elevation in blood pressure. On initial evaluation, blood pressure should be checked in both arms. Elevated blood pressure should then be confirmed on two follow-up visits before a diagnosis of hypertension is made. Sometimes hypertension will be diagnosed and treated immediately due to findings on physical exam or routine testing that confirm complications of untreated hypertension.

About 20-30% of patients have "White-Coat" hypertension, that is elevated blood pressure only in the physician office or hospital setting. Measurement of blood pressure with home blood pressure cuffs or 24 hour ambulatory blood pressure cuffs will be normal in these people. Even in patients with true hypertension, physician office systolic blood pressure is typically 10 points higher than home systolic blood pressure.

Detection and treatment of hypertension is important because hypertension is common, and untreated hypertension decreases life-expectancy by 10-20 years . The consequences of untreated or inadequately treated hypertension include stroke, heart failure , development of coronary and peripheral vascular disease, and kidney failure , among others.

Certain people are at increased risk of developing hypertension; they include those with diabetes, obesity, sleep apnea, physical inactivity, high levels of alcohol intake and smoking .

The vast majority of hypertensives have Primary hypertension (meaning no specific cause of hypertension can be identified). Treatment in these cases consists of life-style modification and drug therapy.

About 5 - 10% of patients have an identifiable, Secondary cause of hypertension . Renovascular hypertension , which is elevation of the blood pressure due to narrowing of the blood vessels supplying the kidneys is seen in up to 5% of patients with hypertension; it is especially common in patients with preexisting coronary or cerebrovascular disease, and in diabetics. Hypertension can sometimes be cured and medications withdrawn after successful restoration of normal blood flow to the kidneys, usually by balloon angioplasty and stent placement in the renal arteries. Diseases affecting the kidneys themselves may also lead to hypertension, so kidney function should always be checked when evaluating a new patient with hypertension. There are a few endocrine tumors that rarely cause hypertension; surgical removal of these may be curative. Oral contraceptives (birth control pills) may lead to the development of hypertension or cause early onset of hypertension in about 1% of users.

There are many classes of drugs available for the treatment of hypertension. Most important is ensuring that control is adequate. Generally, once therapy is initiated, systolic blood pressure should be less than 140 mmHg (ideally closer to 120 mmHg) and diastolic blood pressure should be less than 85 mmHg . The more cardiovascular risk factors that a person has, the more important is becomes to have excellent blood pressure control. Initial steps include life-style modifications: weight loss, exercise, moderation of alcohol and salt intake, and avoidance of tobacco. Drug therapy is often (but not always) necessary, and certain drugs are better for certain patients; you should ask your physician.

Hypertension is often called the " Silent Killer ", but its complications including heart attack , stroke and kidney failure are anything but silent.