High blood pressure facts
- High blood pressure (hypertension) is designated as either essential (primary) hypertension or secondary hypertension and is defined as a consistently elevated blood pressure exceeding 140/90 mm Hg.
- High blood pressure is called "the silent killer" because it often causes no symptoms for many years, even decades, until it finally damages certain critical organs.
- Poorly controlled high blood pressure ultimately can cause damage to blood vessels in the eye, thickening of the heart muscle and heart attacks, hardening of the arteries (arteriosclerosis),kidney failure, and strokes.
- Most antihypertensive medications can be used alone or in combination. Some are used only in combination. Some are preferred over others in certain specific medical situations. And some are not to be used (contraindicated) in other situations.
- Several classes of antihypertensive medications are available, including ACE inhibitors, ARB drugs, beta-blockers, diuretics, calcium channel blockers, alpha-blockers, and peripheral vasodilators.
- The goal of therapy for hypertension is to bring the blood pressure down below 140/85 in the general population and to even lower levels in diabetics, African Americans, and people with certain chronic kidney diseases.
- High blood pressure (hypertension) in pregnancy can lead topreeclampsia or eclampsia (toxemia of pregnancy). Pregnant women should be monitored closely by their obstetrician for complications of high blood pressure.
- Lifestyle adjustments in diet and exercise and compliance with medication regimes are important factors in determining the outcome for people with hypertension.
- High salt intake, obesity, lack of regular exercise, excessive alcohol or coffee intake, and smoking may all adversely affect the outlook for the health of an individual with high blood pressure.
What is high blood pressure?
High blood pressure (HBP) or hypertension means high pressure (tension) in the arteries. Arteries are vessels that carry blood from the pumping heart to all the tissues and organs of the body. High blood pressure does not mean excessive emotional tension, although emotional tension and stress can temporarily increase blood pressure. Normal blood pressure is below 120/80; blood pressure between 120/80 and 139/89 is called "pre-hypertension", and a blood pressure of 140/90 or above is considered high.
The top number, the systolic blood pressure, corresponds to the pressure in the arteries as the heart contracts and pumps blood forward into the arteries. The bottom number, the diastolic pressure, represents the pressure in the arteries as the heart relaxes after the contraction. The diastolic pressure reflects the lowest pressure to which the arteries are exposed.
An elevation of the systolic and/or diastolic blood pressure increases the risk of developing heart (cardiac) disease, kidney (renal) disease, hardening of the arteries (atherosclerosis or arteriosclerosis), eye damage, and stroke (brain damage). These complications of hypertension are often referred to as end-organ damage because damage to these organs is the end result of chronic (long duration) high blood pressure. For that reason, the diagnosis of high blood pressure is important so efforts can be made to normalize blood pressure and prevent complications.
It was previously thought that rises in diastolic blood pressure were a more important risk factor than systolic elevations, but it is now known that in people 50 years or older systolic hypertension represents a greater risk.
The American Heart Association estimates high blood pressure affects approximately one in three adults in the United States -- 73 million people. High blood pressure is also estimated to affect about two million Americanteens and children, and the Journal of the American Medical Associationreports that many are underdiagnosed. Hypertension is clearly a major public health problem.
How is the blood pressure measured?
The blood pressure usually is measured with a small, portable instrument called a blood pressure cuff (sphygmomanometer). (Sphygmo is Greek for pulse, and a manometer measures pressure.) The blood pressure cuff consists of an air pump, a pressure gauge, and a rubber cuff. The instrument measures the blood pressure in units called millimeters of mercury (mm Hg).
The cuff is placed around the upper arm and inflated with an air pump to a pressure that blocks the flow of blood in the main artery (brachial artery) that travels through the arm. The arm is then extended at the side of the body at the level of the heart, and the pressure of the cuff on the arm and artery is gradually released. As the pressure in the cuff decreases, a health practitioner listens with a stethoscope over the artery at the front of the elbow. The pressure at which the practitioner first hears a pulsation from the artery is the systolic pressure (the top number). As the cuff pressure decreases further, the pressure at which the pulsation finally stops is the diastolic pressure (the bottom number). Measurement of blood pressure can also be done with electronic machines that automatically inflate the cuff and recognize the changes in pulsations.
How is high blood pressure defined?
Blood pressure can be affected by several factors, so it is important to standardize the environment when blood pressure is measured. For at least one hour before blood pressure is taken, avoid eating, strenuous exercise (which can lower blood pressure), smoking, and caffeine intake. Other stresses may alter the blood pressure and need to be considered when blood pressure is measured.
Even though most insurance companies consider high blood pressure to be 140/90 and higher for the general population, these levels may not be appropriate cut-offs for all individuals. Many experts in the field of hypertension view blood pressure levels as a range, from lower levels to higher levels. Such a range implies there are no clear or precise cut-off values to separate normal blood pressure from high blood pressure. Individuals with so-called pre-hypertension (defined as a blood pressure between 120/80 and 139/89) may benefit from lowering of blood pressure with lifestyle modification and possibly medication, especially if there are other risk factors for end-organ damage such as diabetes or kidney disease (lifestyle changes are discussed below).
For some people, blood pressure readings lower than 140/90 may be a more appropriate normal cut-off level. For example, in certain situations, such as in patients with long duration (chronic) kidney diseases that spill (lose) protein into the urine (proteinuria), the blood pressure is ideally kept at 130/80, or even lower. The purpose of reducing the blood pressure to this level in these patients is to slow the progression of kidney damage. Patients with diabetes (diabetes mellitus) may also benefit from blood pressure that is maintained at a level lower than 130/80. In addition, African Americans, who have an increased risk for developing the complications of hypertension, may decrease this risk by reducing their systolic blood pressure to less than 135 and their diastolic blood pressure to 80 or less.
In line with the thinking that the risk of end-organ damage from high blood pressure represents a continuum, statistical analysis reveals that beginning at a blood pressure of 115/75 the risk of cardiovascular disease doubles with each increase in blood pressure of 20/10. This type of analysis has led to an ongoing "rethinking" in regard to who should be treated for hypertension, and what the goals of treatment should be.
What are the signs and symptoms of high blood pressure?
Uncomplicated high blood pressure usually occurs without any symptoms (silently) and so hypertension has been labeled "the silent killer." It is called this because the disease can progress to finally develop any one or more of the several potentially fatal complications such as heart attacks or strokes. Uncomplicated hypertension may be present and remain unnoticed for many years, or even decades. This happens because there are no symptoms, and those affected fail to undergo periodic blood pressure screening.
Some people with uncomplicated hypertension, however, may experience symptoms such as headache, dizziness,shortness of breath, and blurred visionusually with blood pressure that is very high. The presence of symptoms can be a good thing in that they can prompt people to consult a doctor for treatment and make them more compliant in taking their medications. Often, however, a person's first contact with a physician may be after significant damage to the body has occurred. In many cases, a person visits or is brought to the doctor or an emergency department with a heart attack, stroke, kidney failure, or impaired vision (due to damage to the back part of the retina). Greater public awareness and frequent blood pressure screening may help to identify patients with undiagnosed high blood pressure before significant complications have developed.
About one out of every 100 (1%) people with hypertension is diagnosed with severe high blood pressure (accelerated or malignant hypertension) at their first visit to the doctor. In these patients, the diastolic blood pressure (see the following section) exceeds 140 mm Hg! Affected persons often experience severe headache, nausea, visual symptoms, dizziness, and sometimes kidney failure. Malignant hypertension is a medical emergency and requires urgent treatment to prevent a stroke (brain damage).
High Blood Pressure Treatment: Food
Research has shown that following a healthy eating plan can both reduce the risk of developing high blood pressure and lower an already elevated blood pressure.
For an overall eating plan, consider the DASH eating plan. "DASH" stands for "Dietary Approaches to Stop Hypertension," a clinical study that tested the effects of nutrients in food on blood pressure. Study results indicated that elevated blood pressures were reduced by an eating plan that emphasizes fruits, vegetables, and lowfat dairy foods and is low in saturated fat, total fat, and cholesterol. The DASH eating plan includes whole grains, poultry, fish, and nuts and has reduced amounts of fats, red meats, sweets, and sugared beverages.
A second clinical study, called "DASH-Sodium," looked at the effect of a reduced dietary sodium intake on blood pressure as people followed either the DASH eating plan or a typical American diet. Results showed that reducing dietary sodium lowered blood pressure for both the DASH eating plan and the typical American diet. The biggest blood pressure-lowering benefits were for those eating the DASH eating plan at the lowest sodium level (1,500 milligrams per day).
The DASH-Sodium study shows the importance of lowering sodium intake whatever your diet. But for a true winning combination, follow the DASH eating plan and lower your intake of salt and sodium.
SOURCE:
National Heart, Lung, and Blood Institute.
What is high blood pressure?
How is the blood pressure measured?
The blood pressure usually is measured with a small, portable instrument called a blood pressure cuff (sphygmomanometer). (Sphygmo is Greek for pulse, and a manometer measures pressure.) The blood pressure cuff consists of an air pump, a pressure gauge, and a rubber cuff. The instrument measures the blood pressure in units called millimeters of mercury (mm Hg).
The cuff is placed around the upper arm and inflated with an air pump to a pressure that blocks the flow of blood in the main artery (brachial artery) that travels through the arm. The arm is then extended at the side of the body at the level of the heart, and the pressure of the cuff on the arm and artery is gradually released. As the pressure in the cuff decreases, a health practitioner listens with a stethoscope over the artery at the front of the elbow. The pressure at which the practitioner first hears a pulsation from the artery is the systolic pressure (the top number). As the cuff pressure decreases further, the pressure at which the pulsation finally stops is the diastolic pressure (the bottom number). Measurement of blood pressure can also be done with electronic machines that automatically inflate the cuff and recognize the changes in pulsations.
How is high blood pressure defined?
Blood pressure can be affected by several factors, so it is important to standardize the environment when blood pressure is measured. For at least one hour before blood pressure is taken, avoid eating, strenuous exercise (which can lower blood pressure), smoking, and caffeine intake. Other stresses may alter the blood pressure and need to be considered when blood pressure is measured.
Even though most insurance companies consider high blood pressure to be 140/90 and higher for the general population, these levels may not be appropriate cut-offs for all individuals. Many experts in the field of hypertension view blood pressure levels as a range, from lower levels to higher levels. Such a range implies there are no clear or precise cut-off values to separate normal blood pressure from high blood pressure. Individuals with so-called pre-hypertension (defined as a blood pressure between 120/80 and 139/89) may benefit from lowering of blood pressure with lifestyle modification and possibly medication, especially if there are other risk factors for end-organ damage such as diabetes or kidney disease (lifestyle changes are discussed below).
For some people, blood pressure readings lower than 140/90 may be a more appropriate normal cut-off level. For example, in certain situations, such as in patients with long duration (chronic) kidney diseases that spill (lose) protein into the urine (proteinuria), the blood pressure is ideally kept at 130/80, or even lower. The purpose of reducing the blood pressure to this level in these patients is to slow the progression of kidney damage. Patients with diabetes (diabetes mellitus) may also benefit from blood pressure that is maintained at a level lower than 130/80. In addition, African Americans, who have an increased risk for developing the complications of hypertension, may decrease this risk by reducing their systolic blood pressure to less than 135 and their diastolic blood pressure to 80 or less.
In line with the thinking that the risk of end-organ damage from high blood pressure represents a continuum, statistical analysis reveals that beginning at a blood pressure of 115/75 the risk of cardiovascular disease doubles with each increase in blood pressure of 20/10. This type of analysis has led to an ongoing "rethinking" in regard to who should be treated for hypertension, and what the goals of treatment should be.
What are the signs and symptoms of high blood pressure?
Uncomplicated high blood pressure usually occurs without any symptoms (silently) and so hypertension has been labeled "the silent killer." It is called this because the disease can progress to finally develop any one or more of the several potentially fatal complications such as heart attacks or strokes. Uncomplicated hypertension may be present and remain unnoticed for many years, or even decades. This happens because there are no symptoms, and those affected fail to undergo periodic blood pressure screening.
Some people with uncomplicated hypertension, however, may experience symptoms such as headache, dizziness,shortness of breath, and blurred visionusually with blood pressure that is very high. The presence of symptoms can be a good thing in that they can prompt people to consult a doctor for treatment and make them more compliant in taking their medications. Often, however, a person's first contact with a physician may be after significant damage to the body has occurred. In many cases, a person visits or is brought to the doctor or an emergency department with a heart attack, stroke, kidney failure, or impaired vision (due to damage to the back part of the retina). Greater public awareness and frequent blood pressure screening may help to identify patients with undiagnosed high blood pressure before significant complications have developed.
About one out of every 100 (1%) people with hypertension is diagnosed with severe high blood pressure (accelerated or malignant hypertension) at their first visit to the doctor. In these patients, the diastolic blood pressure (see the following section) exceeds 140 mm Hg! Affected persons often experience severe headache, nausea, visual symptoms, dizziness, and sometimes kidney failure. Malignant hypertension is a medical emergency and requires urgent treatment to prevent a stroke (brain damage).
High Blood Pressure Treatment: Food
Research has shown that following a healthy eating plan can both reduce the risk of developing high blood pressure and lower an already elevated blood pressure.
For an overall eating plan, consider the DASH eating plan. "DASH" stands for "Dietary Approaches to Stop Hypertension," a clinical study that tested the effects of nutrients in food on blood pressure. Study results indicated that elevated blood pressures were reduced by an eating plan that emphasizes fruits, vegetables, and lowfat dairy foods and is low in saturated fat, total fat, and cholesterol. The DASH eating plan includes whole grains, poultry, fish, and nuts and has reduced amounts of fats, red meats, sweets, and sugared beverages.
A second clinical study, called "DASH-Sodium," looked at the effect of a reduced dietary sodium intake on blood pressure as people followed either the DASH eating plan or a typical American diet. Results showed that reducing dietary sodium lowered blood pressure for both the DASH eating plan and the typical American diet. The biggest blood pressure-lowering benefits were for those eating the DASH eating plan at the lowest sodium level (1,500 milligrams per day).
The DASH-Sodium study shows the importance of lowering sodium intake whatever your diet. But for a true winning combination, follow the DASH eating plan and lower your intake of salt and sodium.
SOURCE:
National Heart, Lung, and Blood Institute.
National Heart, Lung, and Blood Institute.
No comments:
Post a Comment