Join Now | Sign in

Hypertension Health Article

Media Gallery

	African-Americans and High Blood Pressure play video read transcript
	What Is Hypertension? play video read transcript
	High Blood Pressure and Kidney Disease: How Are They Connected? play video read transcript
	Erectile Dysfunction & Hypertension play video read transcript

Marketplace

Licensed from

Page: 1 2 Next >

Hypertension

Blood pressure is the force with which blood pushes against the artery walls as it travels through the body. Like air in a balloon, blood fills arteries to a certain capacity—and just as too much air pressure can cause damage to a balloon, too much blood pressure can harm healthy arteries. Blood pressure is measured by two numbers—systolic pressure and diastolic pressure. Systolic pressure measures cardiac output and refers to the pressure in the arterial system at its highest. Diastolic pressure measures peripheral resistance and refers to arterial pressure at its lowest. Blood pressure is normally measured at the brachial artery with a sphygmomanometer (pressure cuff) in millimeters of mercury (mm Hg) and given as systolic over diastolic pressure.

A blood pressure reading thus appears as two numbers. The upper number is the systolic pressure, which is the peak force of blood as the heart pumps it. The lower number is the diastolic pressure, which is the pressure when the heart is filling or relaxing before the next beat. Normal blood pressure for an adult is 120/70 (on average), but normal for an individual varies with the height, weight, fitness level, age, and health of a person.

What Is Hypertension?

Hypertension, or high blood pressure, is defined as a reading of 140/90 on three consecutive measurements at least six hours apart. The definition varies for pregnant women, where hypertension is defined as 140/90 on two consecutive measurements six hours apart. Consistently high blood pressure causes the heart to work harder than it should and can damage the coronary arteries, the brain, the kidneys, and the eyes. Hypertension is a major cause of stroke.

Types of Hypertension

Hypertension is classified as either primary (or essential) hypertension or secondary hypertension. Primary hypertension has no specific origin but is strongly associated with lifestyle. It is responsible for 90 to 95 percent of diagnosed hypertension and is treated with stress management, changes in diet, increased physical activity, and medication (if needed). Secondary hypertension is responsible for 5 to 10 percent of diagnosed hypertension. It is caused by a preexisting medical condition such as congestive heart failure, kidney failure, liver failure, or damage to the endocrine (hormone) system.

Pregnancy-induced hypertension (PIH) may appear in otherwise healthy women after the twentieth week of pregnancy. It is more likely to occur in women who are overweight or obese. PIH may be mild or severe, and it is accompanied by water retention and protein in the urine. About 5 percent of PIH cases progress to preeclampsia. Preeclampsia is characterized by dizziness, headache, visual disturbance, abdominal pain, facial edema, poor appetite, nausea, and vomiting. Severe preeclampsia affects the mother's blood system, kidneys, brain, and other organs. In rare cases, the woman can die. Preeclampsia is more likely to occur during first pregnancies, multiple fetuses, in women with existing hypertension, and in women younger than twenty-five years old or over thirty-five years old. If convulsions occur with PIH, it is called eclampsia. PIH disappears within a few weeks after birth.

Causes of Hypertension

Many prescription and over-the-counter drugs can cause or exacerbate hypertension. For example, corticosteroids and immunosuppressive drugs increase blood pressure in most solid-organ transplant recipients. Medication taken for pain and inflammation such as nonsteroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase-2 (COX-2) inhibitors may raise blood pressure since their antiprostaglandin properties affect the kidneys.

Tobacco products (cigarettes, cigars, smokeless tobacco) contain nicotine, which temporarily increases blood pressure (for about thirty minutes or less). The blood pressure of smokers should be rechecked after thirty minutes if initial readings are high. Nicotine patches that are used for smoking cessation do not appear to increase blood pressure.

There does not appear to be a direct relationship between caffeine and chronic hypertension, even though caffeine intake can cause an acute (rapid but brief) increase in blood pressure. This may be due to the fact that tolerance to caffeine develops rapidly.

Chronic overuse of alcohol is a potentially reversible cause of hypertension. Five percent of hypertension is due to alcohol consumption and 30 to 60 percent of alcoholics have hypertension. Alcohol-induced hypertension is more likely to occur in women than men.

Page: 1 2 Next >