Facts About High Blood Pressure

High blood pressure, medically termed hypertension, is a common and potentially serious health problem that develops over the course of many years. Blood pressure is determined by the force of blood as it is pumped from the heart through the arteries. Blood pressure rises as the arteries narrow. According to the University of Maryland Medical Center, one in three Americans has high blood pressure, two-thirds of whom are older than age 65.

Causes

• In primary hypertension, accounting for more than 95 percent of all cases, the exact cause is unknown, but several factors contribute to the condition, including genetics; low levels of nitric oxide, a substance in the body that causes the dilation of blood vessels; insulin resistance; and obesity.

  Secondary hypertension is a result of an underlying condition, including disorders of the kidneys and endocrine system, sleep apnea, adrenal gland tumors and congenital heart defects. Certain medications can also contribute to hypertension. These include NSAIDs (nonsteroidal anti-inflammatory drugs) like Aleve and Motrin, birth control pills, steroids and hormone replacement therapy. Chronic use of alcohol, nicotine, cocaine and other stimulants are also potential causes.

Symptoms

• Symptoms are often nonexistent, even in people with dangerously high blood pressure levels. Possible symptoms include severe headache, confusion, nausea, visual disturbances, seizures, dizziness and nosebleeds. These effects are unlikely to manifest until levels are extremely elevated and, even then, they may not appear at all. MayoClinic.com suggests getting blood pressure checked every two years starting at age 20.

Complications

• Hypertension can lead to a number of complications. It can damage arteries; cause aneurysms, in which blood vessels weaken and bulge; heart failure; burst blood vessels in the brain (stroke); and prevent the kidneys and eyes from working properly. Hypertension can also prompt metabolic disorders, which comprise a group of medical problems that affect the body's metabolism as well as affect memory and mental functioning.

  An optimal blood pressure reading to avoid cardiovascular risk is 120/80 mm Hg. Dangerous readings are those hovering around 140/90 mm Hg or higher.

Risk Factors

• Certain risk factors cannot be controlled. High blood pressure is more likely to occur as we age and is more common in men; women past menopause are more likely to develop hypertension than younger women. It is prevalent among black people and appears at an earlier age than it does in whites; serious complications are more common as well. High blood pressure also runs in families.

  Certain risk factors can be controlled with healthy lifestyle changes. These risk factors include obesity, a sedentary lifestyle, smoking, a high sodium diet with inadequate amounts of potassium and vitamin D, excessive alcohol consumption and poor stress management.

Treatment

• Blood pressure medications are administered depending on blood pressure levels and any other medical conditions currently present.

  Thiazide diuretics aid the kidneys in getting rid of sodium and water, which lessens blood volume. Typically, they are a primary medication in the treatment regimen.

  Beta blockers open the blood vessels and help the heart work less hard, allowing it to beat more slowly and with less force, reducing blood pressure.

  Angiotensin-converting enzyme (ACE) inhibitors stop the formation of chemicals that narrow blood vessels. These medications are especially useful in people with heart disease and kidney failure.

  Calcium channel blockers relax blood vessels and slow the heart rate. Eating grapefruit can interfere with these medications.

  Renin inhibitors reduce the production of renin, an enzyme made in the kidneys that start a series of chemical actions that raise blood pressure.