High Blood Pressure: Secondary Hypertension

What is secondary hypertension?

The cause of most cases of high blood pressure is unknown. This kind of high blood pressure is called essential hypertension. High blood pressure caused by some other disease or condition is called secondary hypertension. Most cases of secondary hypertension are related to kidney or hormonal problems.

Three or more separate blood pressure readings higher than 140/90 indicate high blood pressure. The upper, systolic (pumping) pressure may be high; the lower, diastolic (resting) pressure may be high; or both pressures may be high.

How does it occur?

Many diseases, medical conditions, and medications cause secondary hypertension, including:

  • narrowing of the arteries in the kidneys
  • several types of kidney disease
  • narrowing of the aorta, a large blood vessel that supplies blood to the entire body
  • excess secretion of a hormone called aldosterone from the adrenal gland
  • tumor of the adrenal gland
  • Cushing's syndrome, a disorder in which there is an excessive amount of steroid hormones in the blood
  • Hyperthyroidism
  • certain drugs
  • abuse of illicit drugs
  • pregnancy.
What are the symptoms?

High blood pressure may not cause any symptoms. Even secondary hypertension may have few symptoms. Symptoms are usually general and may include:

  • headaches
  • dizziness
  • fatigue
  • restlessness and sleeplessness
  • nosebleeds
  • palpitations or an awareness of your heartbeat
  • general feeling of ill health
  • frequent urination (if excessive aldosterone levels are present)
  • round or "moon" face, excess body and facial hair, and weight gain if the high blood pressure is caused by Cushing's syndrome.
How is it diagnosed?

Your health care provider will ask about your symptoms and medical history and will do a physical exam. Tests of your blood, chest x-rays, and an electrocardiogram may be ordered . Your provider will want to measure your blood pressure on two or three different days when you are relaxed and not in a hurry and have not had alcohol for 72 hours. The average of these blood pressure measurements will be noted.

Your medical history is an important part of diagnosis. Your health care provider will ask about your personal and family history of high blood pressure and heart or kidney disease. (S)he may also need to assess your weight and height and conduct a complete physical exam, to help identify the cause of the hypertension. A fundoscopic eye exam may also be necessary.

How is it treated?

Secondary hypertension is treated by treating the underlying cause. For example, if you have high blood pressure caused by Cushing's syndrome, treatment for Cushing's will likely lower your blood pressure.

How long will the effects last?

If the cause can be diagnosed and treated, your blood pressure should improve. You may be able to cut down or stop taking your medicines if your underlying condition is treated.

How can I take care of myself?
  • Take medications as prescribed. Don't abruptly stop or decrease your medications without asking your health care provider. It is dangerous to suddenly stop taking certain blood pressure medications.
  • If you smoke, quit.
  • Reduce the salt and fat content in your diet according to your health care provider's advice.
  • With your provider's approval, start an exercise program that you can do regularly (such as biking or walking).
  • Lose weight if necessary.
  • Limit the amount of alcohol you drink.
  • Reduce stress or learn to use stress management techniques.
  • Monitor your blood pressure regularly. You can do it yourself or have a health care professional check it. Keep a chart of the readings.
  • See your health care provider as often as he or she recommends.
What can be done to help prevent secondary hypertension?

Most of the conditions that cause secondary hypertension cannot be prevented. However, regular checkups can help detect many conditions before they become serious, including those that can result in high blood pressure.

Developed by Phyllis G. Cooper, R.N., M.N., and iMcKesson Clinical Reference Products.
Published by iMcKesson Clinical Reference Products.
Copyright 1991-2000 iMcKesson LLC. All rights reserved.

Adapted from content provided by iMcKesson, LLC
Review Date: 6/9/2001