Prehypertension
Encyclopedia
Prehypertension is an American classification for cases where a person's blood pressure
is elevated above normal but not to the level considered to be hypertension
(high blood pressure). The seventh report of the Joint National Committee (JNC 7) proposed a new definition of blood pressure values below 140/90 mm Hg
. Prehypertension is considered to be blood pressure readings with a systolic
pressure from 120 to 139 mm Hg or a diastolic
pressure from 80 to 89 mm Hg. Readings greater than or equal to 140/90 mm Hg are considered hypertension. Classification of blood pressure is based upon two or more readings at two or more separate occasions separated by at least one week.
(NHANES III) estimated that the prevalence of prehypertension among adults in the United States
was approximately 31 percent. The prevalence was higher among men than women (39 and 23 percent, respectively).
. Blood pressure also tends to increase as a person ages.
for prehypertension is being overweight. Other risk factors include a family history
of hypertension
, a sedentary lifestyle, eating high sodium
foods, smoking
, and excessive alcohol
intake. Blood pressure levels appear to be familial, but there is no clear genetic pattern.
(without symptoms) at the time of diagnosis. Only extremely elevated blood pressure (malignant hypertension
) can, in rare cases, cause headache
s, visual changes, fatigue, or dizziness, but these are nonspecific symptoms which can occur with many other conditions. Thus, blood pressures above normal can go undiagnosed for a long period of time.
Similar to hypertension, prehypertension can increase the risk for heart attack
s, stroke
s, congestive heart failure, and renal failure
. Researchers found that a prehypertensive person is more than three times more likely to have a heart attack and 1.7 times more likely to have heart disease
than a person with normal blood pressure.
, low-sodium, high potassium
diet (e.g. DASH diet
) is recommended, along with increasing physical activity to at least thirty minutes a day most days of the week, quitting smoking, reducing alcohol consumption, and maintaining a healthy weight.
Some research indicates that the link between low-fat, low-sodium diets may have little to no effect on treating hypertension, particularly in cases of diabetics. There are also links to high-carbohydrate diets heavy in refined carbohydrates (sugar, corn syrup, white flour) as potential sources for increases in blood pressure. Recent research has found that low carbohydrate diets can lower weight and blood pressure in manners similar to medications.
Foods rich in potassium include orange juice, potatoes, bananas, avocados, cantaloupes, tomatoes, broccoli, soybeans, brown rice, garlic and apricots, although it is also abundant in most fruits, vegetables and meats.
has a substantial antihypertensive effect attributable to the flower's ACE-inhibiting anthocyanin content, and possibly to a diuretic effect. One study found that hibiscus conferred an antihypertensive effect comparable to 50 mg./day of the drug captopril.
The major indication for pharmacologic antihypertensive therapy is progression to hypertension. The threshold is lower in patients with diabetes, chronic renal failure, or cardiovascular disease
. The target blood pressure for these conditions is currently less than 120/80 mm Hg.
which results in blood pressure levels being elevated due to the presence of a doctor or physician in a ‘white coat’. Monitoring at home or work at regular times each day will help to diagnose a patient with prehypertension or hypertension.
The American Heart Association
website says, "You may have what's called 'white coat hypertension'; that means your blood pressure goes up when you're at the doctor's office. Monitoring at home will help you measure your true blood pressure and can provide your doctor with a log of blood pressure measurements over time. This is helpful in diagnosing and preventing potential health problems."
People using home blood pressure monitoring devices are increasingly also making use of blood pressure charting software. These charting methods provide print outs for the patients physician and reminders on checking blood pressure.
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
is elevated above normal but not to the level considered to be hypertension
Hypertension
Hypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and...
(high blood pressure). The seventh report of the Joint National Committee (JNC 7) proposed a new definition of blood pressure values below 140/90 mm Hg
Torr
The torr is a non-SI unit of pressure with the ratio of 760 to 1 standard atmosphere, chosen to be roughly equal to the fluid pressure exerted by a millimetre of mercury, i.e., a pressure of 1 torr is approximately equal to 1 mmHg...
. Prehypertension is considered to be blood pressure readings with a systolic
Systole (medicine)
Systole is the contraction of the heart. Used alone, it usually means the contraction of the left ventricle.In all mammals, the heart has 4 chambers. The left and right ventricles pump together. The atria and ventricles pump in sequence...
pressure from 120 to 139 mm Hg or a diastolic
Diastole
Diastole is the period of time when the heart fills with blood after systole . Ventricular diastole is the period during which the ventricles are relaxing, while atrial diastole is the period during which the atria are relaxing...
pressure from 80 to 89 mm Hg. Readings greater than or equal to 140/90 mm Hg are considered hypertension. Classification of blood pressure is based upon two or more readings at two or more separate occasions separated by at least one week.
Prevalence
Data from the 1999 and 2000 National Health and Nutrition Examination SurveyNational Center for Health Statistics
National Center for Health Statistics is a division of the United States federal agency the Centers for Disease Control and Prevention . As such, NCHS is under the United States Department of Health and Human Services...
(NHANES III) estimated that the prevalence of prehypertension among adults in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
was approximately 31 percent. The prevalence was higher among men than women (39 and 23 percent, respectively).
Etiology
Elevated blood pressure develops gradually over many years usually without a specific identifiable cause. However, possible medical causes, such as medications, kidney disease, adrenal problems or thyroid problems, must first be excluded. High blood pressure that develops over time without a specific cause is considered benign or essential hypertensionEssential hypertension
Essential hypertension is the form of hypertension that by definition, has no identifiable cause. It is the most common type of hypertension, affecting 95% of hypertensive patients, it tends to be familial and is likely to be the consequence of an interaction between environmental and genetic...
. Blood pressure also tends to increase as a person ages.
Risk factors
A primary risk factorRisk factor
In epidemiology, a risk factor is a variable associated with an increased risk of disease or infection. Sometimes, determinant is also used, being a variable associated with either increased or decreased risk.-Correlation vs causation:...
for prehypertension is being overweight. Other risk factors include a family history
Family history (medicine)
In medicine, a family history consists of information about disorders from which the direct blood relatives of the patient have suffered. Genealogy typically includes very little of the medical history of the family, but the medical history could be considered a specific subset of the total history...
of hypertension
Hypertension
Hypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and...
, a sedentary lifestyle, eating high sodium
Sodium chloride
Sodium chloride, also known as salt, common salt, table salt or halite, is an inorganic compound with the formula NaCl. Sodium chloride is the salt most responsible for the salinity of the ocean and of the extracellular fluid of many multicellular organisms...
foods, smoking
Smoking
Smoking is a practice in which a substance, most commonly tobacco or cannabis, is burned and the smoke is tasted or inhaled. This is primarily practised as a route of administration for recreational drug use, as combustion releases the active substances in drugs such as nicotine and makes them...
, and excessive alcohol
Ethanol
Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...
intake. Blood pressure levels appear to be familial, but there is no clear genetic pattern.
Symptoms
Prehypertension is often asymptomaticAsymptomatic
In medicine, a disease is considered asymptomatic if a patient is a carrier for a disease or infection but experiences no symptoms. A condition might be asymptomatic if it fails to show the noticeable symptoms with which it is usually associated. Asymptomatic infections are also called subclinical...
(without symptoms) at the time of diagnosis. Only extremely elevated blood pressure (malignant hypertension
Malignant hypertension
Malignant hypertension or hypertensive emergency is severe hypertension with acute impairment of an organ system and the possibility of irreversible organ-damage...
) can, in rare cases, cause headache
Headache
A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the...
s, visual changes, fatigue, or dizziness, but these are nonspecific symptoms which can occur with many other conditions. Thus, blood pressures above normal can go undiagnosed for a long period of time.
Prognosis
People with prehypertension are at a higher risk for developing hypertension, or high blood pressure, compared to people with normal blood pressure.Similar to hypertension, prehypertension can increase the risk for heart attack
Myocardial infarction
Myocardial infarction or acute myocardial infarction , commonly known as a heart attack, results from the interruption of blood supply to a part of the heart, causing heart cells to die...
s, stroke
Stroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...
s, congestive heart failure, and renal failure
Renal failure
Renal failure or kidney failure describes a medical condition in which the kidneys fail to adequately filter toxins and waste products from the blood...
. Researchers found that a prehypertensive person is more than three times more likely to have a heart attack and 1.7 times more likely to have heart disease
Heart disease
Heart disease, cardiac disease or cardiopathy is an umbrella term for a variety of diseases affecting the heart. , it is the leading cause of death in the United States, England, Canada and Wales, accounting for 25.4% of the total deaths in the United States.-Types:-Coronary heart disease:Coronary...
than a person with normal blood pressure.
Treatment
To lower the risk of prehypertension progressing to hypertension, modification of lifestyle or behaviors is necessary.Diet
A low-fatFat
Fats consist of a wide group of compounds that are generally soluble in organic solvents and generally insoluble in water. Chemically, fats are triglycerides, triesters of glycerol and any of several fatty acids. Fats may be either solid or liquid at room temperature, depending on their structure...
, low-sodium, high potassium
Potassium
Potassium is the chemical element with the symbol K and atomic number 19. Elemental potassium is a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive with water, generating sufficient heat to ignite the hydrogen emitted in the reaction.Potassium and sodium are...
diet (e.g. DASH diet
Dietary Approaches to Stop Hypertension
The DASH diet is a diet promoted by the National Heart, Lung, and Blood Institute to control hypertension...
) is recommended, along with increasing physical activity to at least thirty minutes a day most days of the week, quitting smoking, reducing alcohol consumption, and maintaining a healthy weight.
Some research indicates that the link between low-fat, low-sodium diets may have little to no effect on treating hypertension, particularly in cases of diabetics. There are also links to high-carbohydrate diets heavy in refined carbohydrates (sugar, corn syrup, white flour) as potential sources for increases in blood pressure. Recent research has found that low carbohydrate diets can lower weight and blood pressure in manners similar to medications.
Foods rich in potassium include orange juice, potatoes, bananas, avocados, cantaloupes, tomatoes, broccoli, soybeans, brown rice, garlic and apricots, although it is also abundant in most fruits, vegetables and meats.
Supplements
Several studies have found that hibiscus teaHibiscus tea
Hibiscus tea is the infusion made from the calyces of the Hibiscus sabdariffa flower, an herbal tea drink consumed both hot and cold by people around the world...
has a substantial antihypertensive effect attributable to the flower's ACE-inhibiting anthocyanin content, and possibly to a diuretic effect. One study found that hibiscus conferred an antihypertensive effect comparable to 50 mg./day of the drug captopril.
Monitoring
Careful monitoring for signs of end-organ damage or progression to hypertension is an important part of the follow-up of patients with prehypertension. Any change in blood pressure classification should be confirmed on at least one subsequent visit.The major indication for pharmacologic antihypertensive therapy is progression to hypertension. The threshold is lower in patients with diabetes, chronic renal failure, or cardiovascular disease
Cardiovascular disease
Heart disease or cardiovascular disease are the class of diseases that involve the heart or blood vessels . While the term technically refers to any disease that affects the cardiovascular system , it is usually used to refer to those related to atherosclerosis...
. The target blood pressure for these conditions is currently less than 120/80 mm Hg.
Home monitoring of prehypertension
Home monitoring of blood pressure can be used to monitor and track prehypertensive patients. This can help to raise the awareness of the patient and their doctor if their blood pressure levels rise to hypertensive levels. Home monitoring can help to avoid white coat hypertensionWhite coat hypertension
White coat hypertension, more commonly known as white coat syndrome, is a phenomenon in which patients exhibit elevated blood pressure in a clinical setting but not in other settings...
which results in blood pressure levels being elevated due to the presence of a doctor or physician in a ‘white coat’. Monitoring at home or work at regular times each day will help to diagnose a patient with prehypertension or hypertension.
The American Heart Association
American Heart Association
The American Heart Association is a non-profit organization in the United States that fosters appropriate cardiac care in an effort to reduce disability and deaths caused by cardiovascular disease and stroke. It is headquartered in Dallas, Texas...
website says, "You may have what's called 'white coat hypertension'; that means your blood pressure goes up when you're at the doctor's office. Monitoring at home will help you measure your true blood pressure and can provide your doctor with a log of blood pressure measurements over time. This is helpful in diagnosing and preventing potential health problems."
People using home blood pressure monitoring devices are increasingly also making use of blood pressure charting software. These charting methods provide print outs for the patients physician and reminders on checking blood pressure.