$Unique_ID{BRK03847} $Pretitle{} $Title{Hypertension} $Subject{Hypertension Arterial Hypertension High Blood Pressure Essential Primary Hypertension Secondary Hypertension Renal Renovascular Hypertension Systolic Hypertension} $Volume{} $Log{} Copyright (C) 1992 National Organization for Rare Disorders, Inc. 784: Hypertension ** IMPORTANT ** It is possible that the main title of the article (Hypertension) is not the name you expected. Please check the SYNONYM listing to find the alternate names and disorder subdivisions covered by this article. Synonyms Arterial Hypertension High Blood Pressure Disorder Subdivisions: Essential (or Primary) Hypertension Secondary Hypertension Renal (or Renovascular) Hypertension Systolic Hypertension General Discussion ** REMINDER ** The information contained in the Rare Disease Database is provided for educational purposes only. It should not be used for diagnostic or treatment purposes. If you wish to obtain more information about this disorder, please contact your personal physician and/or the agencies listed in the "Resources" section of this report. Hypertension is defined as persistent elevation of blood pressure. Blood pressure is the amount of pressure placed on the walls of the arteries as blood is pumped throughout the body. (Generally, normal blood pressure is considered 120/80, but can be anywhere from 100/60 to 140/90. Blood pressure is measured by an instrument called a sphygmomanometer.) The systolic blood pressure is the upper reading which measures pressure when the heart muscle is contracting. The diastolic blood pressure is the lower reading which measures pressure when the heart muscle is at rest. Blood pressure varies depending on age, altitude, activity, posture and from person to person. When only the systolic blood pressure is high, it is referred to as systolic hypertension. Symptoms Hypertension is ordinarily discovered during a routine examination. There are usually no outward symptoms. However, when blood pressure is extremely high, there may be symptoms of headache, heart failure, and/or vision disturbances. When hypertension is untreated it can cause damage to the heart, blood vessels and kidneys. It can also lead to congestive heart failure, mini-strokes (transient ischemia attacks; TIA), strokes, and kidney failure. This is why it is important for people with high blood pressure to receive medical treatment even though they may feel perfectly healthy. Causes In over 95% of people who have hypertension there is no discernible cause. When the cause is unknown, high blood pressure is referred to as essential or primary hypertension. In secondary hypertension, the cause is known. Some known causes of secondary hypertension are kidney diseases (renal or renovascular hypertension) including kidney failure due to any cause. Endocrine disorders such as Acromegaly, Hyperthyroidism, Cushing's Syndrome, Congenital Adrenal Hyperplasia, or Pheochromocytoma can also cause secondary hypertension. Other causes of hypertension include neurological disorders such as Encephalitis, Acute Porphyria, Familial Dysautonomia, or Guillain-Barre Syndrome. (For more information on these disorders, choose "encephalitis," "porphyria", "dysautonomia," and "Guillain-Barre" as your search terms in the Rare Disease Database.) In some patients, hypertension may be caused by hereditary factors or by high salt intake (especially in people who inherited the tendency to develop hypertension). Other contributing causes are obesity, smoking, alcoholism, oral contraceptives or emotional stress. Affected Population Hypertension is a very common disorder affecting over 60 million Americans as of 1988. Because there are rarely symptoms, many Americans are unaware they have hypertension so these figures may be even higher. Hypertension tends to occur more often in black people than in white; however with age, the incidence of hypertension increase in all groups. Men are affected more often than women before the age of 50; after 50, more women are affected than men. Therapies: Standard Treatment of hypertension includes the use of diuretics (sometimes called "water pills") to reduce sodium and water levels in the body and lower blood pressure. Beta-blocking drugs which reduce constriction of blood vessels, and vasodilators which are drugs that relax the muscles in blood vessel walls are also used. Centrally acting drugs that lower the heart rate by controlling the sympathetic nervous system, and angiotensin converting enzyme (ACE) inhibitors which reduce constriction of blood vessels as well as salt and water levels may be prescribed. People can aid in the control of hypertension if they practice proper weight control, exercise regularly and eat a low sodium diet. Blood pressure machines for home use can be of benefit when people want to monitor their own blood pressure. Therapies: Investigational There is extensive research being pursued on the causes, prevention and treatment of hypertension. For information about this research contact the National Heart, Blood and Lung Institute listed in the Resources section of this report. Clinical trials are underway to study the effects of dietary calcium and sodium manipulation in Essential Hypertension. Interested persons may wish to contact: Dr. Rose Marie Robertson Professor of Medicine CC2218 MCN Vanderbilt University Nashville, TN 37232 (615) 322-2318 to see if further patients are needed for this research. Clinical trials are underway to study patients that develop Supine Hypertension after lesions of the nucleus tactus solitarii. Interested persons may wish to contact: S.H. Subramony, M.D. University of Mississippi Medical Center 2500 N. State St. Jackson, MS 39216 (601) 984-5525 to see if further patients are needed for this research. Clinical trials are underway to study responses to psychologic stressors in ten to eighteen year old patients with Primary Hypertension. Interested persons may wish to contact: Dr. Bruce S. Alpert University of Tennessee Division of Cardiology 848 Adams Ave. Memphis, TN 38103 (901) 522-3380 to see if further patients are needed for this research. This disease entry is based upon medical information available through January 1990. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder. Resources For more information on Hypertension, please contact: National Organization for Rare Disorders P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 American Heart Association 7320 Greenville Ave. Dallas, TX 75231 (214) 750-5300 NIH/National Heart, Blood, and Lung Institute 9000 Rockville Pike Bethesda, MD 20892 (301) 951-3260 References CECIL TEXTBOOK OF MEDICINE, 18th Ed.: James B. Wyngaarden, and Lloyd H. Smith, Jr., Editors; W.B. Saunders Co., 1988. Pp. 276-302. INTERNAL MEDICINE, 2nd Ed.: Jay H. Stein, ed.-in-chief; Little, Brown and Co., 1987. Pp. 553. THE MERCK MANUAL, Volume 1, 14th Ed.: Robert Berkow, M.D., ed.-in-chief; Merck, Sharp, and Dohme Laboratories, 1982. Pp. 390-403.