Cause of High Blood Pressure

Causes of High Blood Pressure

High Blood Pressure Overview

The heart pumps blood into the arteries with enough force to push blood to the far reaches of each organ from the top of the head to the bottom of the feet. Blood pressure can be defined as the pressure of blood on the walls of the arteries as it circulates through the body. Blood pressure is highest as its leaves the heart through the aorta and gradually decreases as it enters smaller and smaller blood vessels (arteries, arterioles, and capillaries). Blood returns in the veins leading to the heart, aided by gravity and muscle contraction.

Hypertension is the medical term for high blood pressure. It is known as the "silent killer" since it has no initial symptoms but can lead to long-term disease and complications..

Many people have high blood pressure and don't know it.

 Important complications of uncontrolled or poorly treated high blood pressure include heart attack, congestive heart failure, stroke, kidney failure, peripheral artery disease, and aortic aneurysms (weakening of the wall of the aorta, leading to widening or ballooning of the aorta).

Public awareness of these dangers has increased. High blood pressure has become the second most common reason for medical office visits in the United States.

How is blood pressure measured?

Blood pressure is measured with a blood pressure cuff and recorded as two numbers, for example, 120/80 mm Hg (millimeters of mercury). Blood pressure measurements are usually taken at the upper arm over the brachial artery.

       The top, larger number is called the systolic pressure. This measures 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.

The American Heart Association has recommended guidelines to define normal and high blood pressure.

       Normal blood pressure less than 120/80

       Pre-hypertension 120-139/ 80-89

       High blood pressure (stage 1) 140-159/90-99

       High blood pressure (stage 2) higher than 160/100

As many as 60 million Americans have high blood pressure.

Uncontrolled high blood pressure may be responsible for many cases of death 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 high blood pressure, particularly systolic hypertension. The higher your blood pressure, the higher the risk. Maintaining lifelong control of hypertension decreases the future risk of complications such as heart attack and stroke.

High Blood Pressure Causes

In 90% of people with hypertension, the cause of high blood pressure is not known and is referred to as primary or essential hypertension. While the specific cause is unknown, there are risk factors that can contribute to developing high blood pressure.

Factors that can not be changed

       Age: The older a person is, the greater the likelihood that he or she will develop high blood pressure, especially elevated systolic readings. This is largely due to arteriosclerosis, or "hardening of the arteries."

Race: African Americans develop high blood pressure more often than Caucasians. They develop high blood pressure at a younger age and develop more severe complications sooner in life.

       Socioeconomic status: High blood pressure is found more commonly among the less educated and lower socioeconomic groups. Residents of the southeastern United States, both Caucasian and African American, are more likely to have high blood pressure than residents of other regions.

Family history (heredity): The tendency to have high blood pressure appears to run in families.

       Gender: 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

Obesity: As body weight increases, the blood pressure rises. Obesity is defined as having a body mass index (BMI) greater than 30 kg/m². A BMI of 25-30 kg/m² is considered overweight (BMI=weight in pounds x 703/ height in inches ²) Being overweight increases the risk of high blood pressure. Health care practitioners recommend that all obese people with high blood pressure lose weight until they are within 15% of their healthy body weight.

Obese people are two to six 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 for high blood pressure than "pear-shaped" people.

       Sodium (salt) sensitivity: Some people have high sensitivity to sodium (salt), and their blood pressure increases 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 also contain large amounts of sodium. Read food labels and learn about salt content in foods and other products as a healthy first step to reducing salt intake. Fast food restaurants also make the salt and calorie content of their food available to consumers at their restaurants,

Alcohol use: Drinking more than one to two drinks 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 high blood pressure.

Medications: Certain drugs, such as amphetamines (stimulants), diet pills, and some medications used for cold and allergy symptoms such as pseudoephedrine, tend to raise blood pressure.