Hypertension
Safe and effective treatment is available either with nondrug programs or with a suitably selected drug. Drug selection is important and is discussed in some detail in the following sections.
HYPERTENSION, COMMONLY KNOWN AS HIGH blood pressure, is a problem suffered by more than 60 million people in the United States from the age of 65 to 75.The incidence of hypertension is higher in African-Americans. There are approximately 1 billion individuals with hypertension worldwide.
The complications of high blood pressure often lead to early death or serious physical handicaps. There are
- I. MEASUREMENT OF BLOOD PRESSURE
The instrument used to measure blood pressure is called a sphygmomanometer. It measures the air pressure needed to raise a column of mercury (Hg). The instrument consists of an inflatable cuff connected to a small bulb pump and a pressure gauge. By means of the inflatable cuff, which encircles the limb (usually the upper arm), air pressure within the cuff is balanced against the pressure in the artery (usually the brachial artery at the elbow). The pressure is estimated by means of a mercury or aneroid manometer. The mercury manometer is the most accurate pressure gauge. The aneroid gauge is frequently used instead of the mercury manometer because it is more compact and is convenient as a portable instrument. Some electronic instruments may give falsely high diastolic readings, but manufacturers will improve these to meet market demands. - II. HOW HIGH IS HIGH?
The World Health Organization (WHO) and many experts agree that in individuals under age 65, a systolic blood pressure equal to or greater than 140 mmHg and a diastolic blood pressure of 90 mmHg or above is ab¬normal. Optimal systolic blood pressure is less than 120 mmHg and optimal diastolic blood pressures are less than 80 mmHg. In patients age 65–80 a systolic pressure greater than 165 on three or more readings weeks or months apart is considered hypertension. The Framingham Study and other studies indicate a significant increase in car¬diovascular risk in individuals with a blood pressure in the borderline range. An individual is considered to have high blood pressure if several readings exceed 140/90, especially if three consecutive readings are elevated. The risk at any level of hypertension, including borderline hypertension, is greatly increased by smoking or a high blood cholesterol. Mild hypertension is extremely common, and over a 10- to 15-year period increases the risk of stroke, heart attack, and heart failure. Clinical studies have documented that blacks develop organ damage (stroke, heart failure, and damage to the kidneys) much quicker than whites at the same level of hypertension. - III. CAUSES OF HYPERTENSION A. Primary (Essential) Hypertension
In the majority of cases of hypertension, no detectable underlying disease is present. There are several theories as to why the blood pressure may be increased. This type - IV. PATHOGENESIS OF PRIMARY ESSENTIAL HYPERTENSION
A. Salt Hypothesis - V. COMPLICATIONS
A. Effects on Arteries and Heart - VI. SYMPTOMS
There is little doubt that hypertension either leads to early death or inflicts serious physical handicaps to millions. Blood pressure may be mildly or moderately elevated for several years without symptoms until the occurrence of stroke, heart attack, or heart failure. - VII. INVESTIGATIONS
Blood, urine, and other tests are performed to determine if hypertension is primary, that is, without a cause, or secondary to diseases of organs, especially the kidney. These tests will also serve as a baseline for future com¬parison and as a means for detecting side effects of some antihypertensive drugs. The tests and the reasons for their use are listed below. - VIII. NONDRUG TREATMENT
The majority of patients with mild primary hypertension are advised to persist with a one-year trial of nondrug treatment. It is important to understand the essential requirements of the program. The hypertensive must be aware of the dangers of the so-called silent killer to become sufficiently motivated to comply with self-imposed treatment. Individuals who persist with nondrug treatment - IX. DRUG TREATMENT
A. Number of Drugs Available - BIBLIOGRAPHY
ALLHAT: Officers and Coordinators for the ALLHAT Collabo¬rative Research Group. JAMA, 288:2981–2997, 2002. ALLHAT: The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial. Major cardiovascular events in hypertensive patients randomized to doxazosin vs. chlorthalidone. The ALLHAT