When the heart pumps blood into the arteries, the blood flows with a force pushing against the walls of the arteries. This force is called the blood pressure. When your blood pressure is measured, it is a measure of how hard the heart has to work to pump the blood.
When the arteries become hardened and narrowed with cholesterol plaque and calcium (atherosclerosis), the heart has to strain much harder to pump blood through them. This makes the blood pressure go abnormally high. High blood pressure is also called hypertension.
What makes high blood pressure important is that it usually causes no symptoms but can still cause serious complications.
Many people have high blood pressure and don't even know it.
The complications of high blood pressure include heart disease, heart attack, kidney failure, vision loss, and stroke.
Public awareness of these dangers has increased. High blood pressure has become the second most common reason for medical visits in the United States.
Blood pressure is measured with a Blood Pressure Monitor and recorded as 2 numbers, such as 120/80 mm Hg (millimeters of mercury).
The top, larger number is called the systolic pressure. This is the pressure generated when the heart contracts (pumps). It reflects the pressure of the blood against arterial walls.
The bottom, smaller number is called the diastolic pressure. This reflects the pressure in the arteries while the heart is filling and resting between heartbeats.
Scientists have determined a normal range for both systolic and diastolic blood pressure after examining the blood pressure of many people.
Those whose blood pressure is consistently higher than this norm are said to have high blood pressure or hypertension.
High blood pressure in adults is defined as a consistently elevated blood pressure of 140 mm Hg systolic and 90 mm Hg diastolic or higher.
As many as 60 million Americans have high blood pressure.
That's about 1 in 4 adults aged 18 years and older.
Uncontrolled high blood pressure is indirectly responsible for many deaths and disability resulting from heart attack, stroke, and kidney failure.
According to research studies, the risk of dying of a heart attack is directly linked to blood pressure. The higher your blood pressure, the higher your risk.
The progress of heart disease caused by high blood pressure can be slowed down, however.
High Blood Pressure Causes
In about 10% of people, high blood pressure occurs as a symptom of another disease (this is called secondary hypertension). In such cases, when the root cause is treated, blood pressure usually returns to normal. These causes include the following conditions:
-Tumors or other diseases of the adrenal gland
-Chronic kidney disease
-Hormone abnormalities involving the adrenal glands or pituitary gland
-Pregnancy
-Use of birth control pills
-Alcohol addiction
Coarctation of the aorta - A narrowing of the aorta that you are born with that can cause high blood pressure in your arms
Thyroid dysfunction
In the other 90% of cases, the cause of high blood pressure is not known (primary hypertension). Although the specific cause is unknown, certain factors are recognized as contributing to high blood pressure.
Factors That Can't be Changed
Age: The older you get, the greater the likelihood that you will develop high blood pressure. This is largely due to atherosclerosis, or "hardening of the arteries."
Race: African Americans have high blood pressure more often than whites. They develop high blood pressure at a relatively younger age. Their high blood pressure and complications tend to be more severe as well.
Socioeconomic status: High blood pressure is also more common among the less educated and among lower socioeconomic groups. Residents of the southeastern United States, both whites and blacks, are more likely to have high blood pressure than Americans from other regions.
Family history (heredity): The tendency to have high blood pressure appears to run in families.
Sex: Generally, men have a greater likelihood of developing high blood pressure than women. This likelihood varies according to age and among various ethnic groups.
Factors that can be changed
Overweight (obesity): Obesity is defined as being 30% or more over your healthy body weight. It is very closely related to high blood pressure. Medical professionals strongly recommend that all obese people with high blood pressure lose weight until they are within 15% of their healthy body weight. Your health care provider can help you calculate your healthy range of body weight.
Sodium (salt) sensitivity: Some people have high sensitivity to sodium (salt), and their blood pressure goes up if they use salt. Reducing sodium intake tends to lower their blood pressure. Americans consume 10-15 times more sodium than they need. Fast foods and processed foods contain particularly high amounts of sodium. Many over-the-counter medicines, such as painkillers, also contain large amounts of sodium. Read labels to find out how much sodium is contained in food items. Avoid those with high sodium levels.
Alcohol use: Drinking more than 1 ounce of alcohol per day tends to raise blood pressure in those who are sensitive to alcohol.
Birth control pills (oral contraceptive use): Some women who take birth control pills develop high blood pressure.
Lack of exercise (physical inactivity): A sedentary lifestyle contributes to the development of obesity and sometimes high blood pressure.
Drugs:
Certain drugs, such as amphetamines (stimulants), diet pills, and some pills used for cold and allergy symptoms, tend to raise blood pressure.
As body weight increases, the blood pressure rises.
Obese people are 2-6 times more likely to develop high blood pressure than people whose weight is within a healthy range.
Not only the degree of obesity is important, but also the manner in which the body accumulates extra fat. Some people gain weight around their belly (central obesity or "apple-shaped" people), while others store fat around their hips and thighs ("pear-shaped" people). "Apple-shaped" people tend to have greater health risks than "pear-shaped" people.
