What is Hypertension - General Information

Blood travels through your body by flowing through arteries, carrying oxygen-rich blood from your heart to other tissues and organs. Once oxygen is delivered to your tissues and organs, oxygen-poor blood travels back to your heart through your veins. Your heart then pumps this blood into your lungs, where it is replenished

with oxygen. After returning to your heart, the blood is pumped out into your arteries again. Blood pressure is the force exerted by blood against artery walls as it circulates through your body. This is what is measured at your doctor's office.

Your body monitors and adjusts blood pressure through a complex interaction between your heart, blood vessels (arteries and veins), nervous system, kidneys, and several hormones, in response to various stimuli.

Many things can cause blood pressure to rise. When you are asleep, your blood pressure is low because your body needs less oxygen-rich blood when it is at rest. On the other hand, when you are exercising, your body's demands are greater, and so your blood pressure increases.

It is perfectly normal for your blood pressure to rise and fall in response to your body's needs throughout the day. Remember, hypertension is when your blood pressure is sustained above your normal range.

There are several risk factors that may contribute to whether or not you develop hypertension. Some of these, such as weight, diet, and lifestyle, are examples of risk factors you can control. Consumption of alcoholic beverages and smoking, which cause blood pressure to rise, are examples of risk factors you have the power to eliminate. Other risk factors, such as age, heredity, race, and gender, cannot be changed.

Hypertension or high blood pressure, results from either an increase in the amount of blood that is pumped by the heart or an increased resistance to blood as it flows through the arteries. In other words, the flow of blood travels through narrowed arteries, requiring your heart to pump harder just to keep the blood flowing.

Remember, as blood pressure increases, the strain becomes greater on your arteries as well as on your heart. This increased strain means that your heart must work much harder all the time. The result - an enlarged heart that is increasingly less effective in pumping blood throughout your body.

It is possible to have hypertension and not know it. Many people with this condition do not have any obvious symptoms, meaning they are "asymptomatic". It is, therefore, very important to have regular check-ups with your doctor and follow his or her instructions; left untreated, hypertension can result in serious complications.

Blood pressure is measured in fractions of millimeters of mercury (mmHg) by means of a special instrument called a sphygmomanometer . It has an inflatable rubber cuff attached to a pressure-monitoring device. The two numbers that indicate your blood pressure are expressed as a fraction, for example, 120/80 mmHg. The first number is the systolic pressure (when the heart contracts to pump blood through the arteries); the second number is the diastolic pressure (when the heart relaxes and fills with blood for the next contraction).

When your blood pressure is measured in your doctor's office, the cuff is placed around your arm and pumped up with air to momentarily stop the circulation of blood. When the pressure inside the cuff is reduced, the blood starts to flow again. The person measuring your blood pressure uses a stethoscope to listen to the sounds the blood makes as it flows through your arteries. By listening closely to these sounds and noting on the sphygmomanometer the exact numbers at which they start and stop, the systolic and diastolic pressures can be measured.

At-home sphygmomanometer

The increasing interest in hypertension has resulted in the development of home monitoring devices for blood pressure. Many different models are available, but they all have a display, sometimes digital, from which you can read your blood pressure.

Although some people have no trouble using these devices, others do. And if you do have hypertension, it is important to have your blood pressure checked regularly by your doctor.

Determining the Severity

The numbers—systolic pressure and diastolic pressure --indicate how high or low your blood pressure is. If you do have hypertension, your doctor can use the numbers to help determine the severity. The table below, based on the United States study by the Joint National Committee, may be used as a guide.

Category of Blood Pressure	Systolic Pressure (mmHg)	Diastolic Pressure (mmHg)
Normal	< 130	< 85
High normal	130 - 139	85 - 89
Hypertension
Stage I / Mild	140 - 159	90 - 99
Stage II / Moderate	160 - 179	100 - 109
Stage III / Severe	180 - 209	110 - 119
Stage IV / Very severe	>210	>120

Remember, if you have hypertension--whether it is mild, moderate, severe, or very severe--it can be treated through a program of lifestyle and medication. And it is very important to follow your doctor's directions exactly.

Types of Hypertension

Besides being classified according to measured pressure elevation, hypertension can also be classified according to its cause.

Primary hypertension
The majority of people with hypertension have primary hypertension, the cause of which is unknown. It is also called essential or idiopathic hypertension, and various factors are thought to contribute to its development. However, the exact cause often cannot be determined in a particular patient.

Secondary hypertension

Hypertension is defined as secondary when a specific cause can be pinpointed. This is most frequently due to a kidney (renal) disorder or another condition that affects the kidneys. Other diseases can result in secondary hypertension. If the disease is successfully treated, the secondary hypertension may be resolved as well. Certain medications can also have adverse effects on blood pressure, resulting in secondary hypertension.

Renovascular hypertension
A less common form, renovascular hypertension, can result from the narrowing of one or both of the main arteries supplying the kidneys (renal arteries).

Complications of Hypertension

If you suspect you have hypertension, it is crucial that you see your doctor. Once hypertension is diagnosed, effective treatment can be started. But remember, it is also important to see your doctor regularly for follow-up visits, and report any side effects you might be experiencing.

Untreated hypertension can cause very serious complications. People with hypertension have a higher risk of both heart attack and stroke. Hypertension also increases the risk of developing certain diseases of the heart, blood vessels, kidney, and brain. However, effective treatment of hypertension can help prevent such dangerous complications.

Who is at Risk?

If you have high blood pressure, or hypertension, you are not alone. It is one of the most common conditions for which people receive medication.

Left untreated, mild hypertension, which may have no symptoms, can progress to severe hypertension. This can lead to a life-threatening condition, such as a heart attack, a stroke, or kidney disease. That is why it is so important that you see your doctor regularly for checkups.

Although some of us are at greater risk than others, everyone has some potential for developing hypertension, along with the medical complications it can cause. You may be male or female, young or old, active or inactive, overweight or thin, and of any race or ethnic group. Your lifestyle may be highly stressed or very relaxed, and your family history may or may not include relatives who have had hypertension or heart disease. Perhaps you are undergoing treatment for diabetes, heart disease, cancer, or another chronic condition. Simply put, it does not matter who you are--you can be at risk for hypertension and its consequences.

Is This You?

Do you think your blood pressure may be high but have not spoken to your doctor about it? Consider the following questions.

Regarding your medical history:
1. Have you previously taken medication for high blood pressure but quit?
2. Do you have a family history of hypertension or heart disease?

Regarding your lifestyle:
1. Do you get little or no regular physical exercise?
2. Are you overweight for your height, age, and build?
3. Do you smoke or use tobacco?
4. Do you eat a lot of salty foods or add a lot of salt to your food?
5. Is your diet high in cholesterol and/or saturated fats?
6. Do you drink alcoholic beverages?
7. Are you stressed or anxious at work and/or at home?

If you can answer "yes" to any of these questions, it is essential that you consult with your doctor.

Treatment is Available

Although you may think that it is bad news if you have been diagnosed with hypertension, there is good news. Effective treatment is available. The main goal of treatment is to bring hypertension under control quickly and permanently. Compliance with therapy and following your doctor's directions are essential.

But in order to bring hypertension under control, lifestyle changes (such as eating right, maintaining the correct weight, and quitting smoking) are necessary. You may also have to take some antihypertensive medication to help control your hypertension. And you must take your medication exactly the way your doctor tells you to.

Lifestyle Changes

If you and your doctor discover that you do have hypertension, there are some very effective steps that you can follow to take control. The first thing to do is to make sure your lifestyle is in order.

· Are you prone to reaching for the salt shaker and pouring on the salt before you even pick up your fork?

· Do you feel as if you cannot make it through the day without a constant supply of caffeine?

Depending on your condition, your doctor may ask you to make some changes in your lifestyle. These will be for the better. It may be difficult at first to make these healthy changes, but soon you will be feeling and looking better and wondering why you did not do it sooner. And best of all, for many people, blood pressure will decrease. In some cases, your doctor may also prescribe medication at this stage or after a few weeks of these lifestyle changes. If the changes have proven effective, meaning your blood pressure has come down, then you will be advised to continue them and to be sure to have your blood pressure frequently monitored.

The following are some factors about your lifestyle that may make you more likely to develop hypertension. Some of them you have the power to change, but there are others you cannot.

· Obesity
People who are obese are 30 percent or more above the ideal weight for their height, age,

and build. This is very dangerous for their health. Maintaining your ideal weight can reduce your chance of developing hypertension. You can do this by eating right and getting enough exercise. You may think this is hard, but it does work. Talk to your doctor about a sensible weight-loss program. Sometimes, losing weight can help lower your blood pressure.

· Smoking/Tobacco Use
One of the goals of controlling hypertension with medication is to protect you from the risk of developing heart disease and stroke. Smoking decreases the protective effects of hypertension medications in preventing heart disease and stroke. Therefore, it is extremely important to avoid tobacco use if you have hypertension. If you are already a smoker, there are many programs available to help you quit the habit.

· Nutrition
People who have poor diets or who skip meals frequently may not be getting enough important nutrients, such as calcium, potassium, and magnesium. Proper levels of

these minerals are essential for overall health. Excessive alcohol consumption may also raise blood pressure, as may consuming large amounts of fat. Excess intake of salt (also called sodium) causes water retention. The increased water in the body makes blood pressure rise.

· Age
As people age, their chance of developing hypertension tends to increase. Many factors affecting overall health, such as weight, diet, lifestyle, and environmental influences, may contribute to this tendency.

· Heredity (Family History)
If your parents or brothers or sisters have hypertension, there is a very good chance that you will develop it too. That is why it is important that your doctor take a family history during your

examination. If you do not know whether your family members have hypertension, ask. It is especially a concern if a close family member has severe hypertension or has died from heart disease before the age of 55.

· Race and Ethnicity
Certain ethnic backgrounds have a greater chance of developing hypertension. For example, African Americans may develop hypertension when they are young. If and when hypertension develops, it can also be more severe. As a result, serious consequences related to hypertension, such as stroke and heart disease, can develop more frequently in people of certain ethnic groups.

· Gender
No concise clinical data yet exist to differentiate hypertension in men versus women, especially young and middle-aged women. Birth control pills and pregnancy can occasionally cause hypertension in women, and these should always be considered in hypertensive women.

· Stress
There has been a connection established between stress in the working environment and hypertension. It can only benefit you to try and decrease or eliminate the amount of stress in your life. The role of relaxation treatments as an effective treatment to lower stress-related hypertension has not been proven. If you have any questions, consult your physician.

· Exercise
Studies have shown that regular exercise helps control blood pressure. Lack of exercise is a strong risk factor for heart disease, especially if you have hypertension. You do not have to run a marathon or spend most of the day in the gym to reap the benefits of exercise. Moderate exercise is enough. Just pick something you enjoy--and stick with it.

Medications

For some people, lifestyle changes are not enough to reduce blood pressure to normal levels. But there is help for these people too. Through medical research, a variety of medications have been developed that effectively reduce hypertension.

Since no two people are exactly alike, antihypertensive therapy is different for each person. Your doctor will prescribe medication based on your medical condition.

Antihypertensive medications fall into one of several major categories:

Angiotensin II (A II) Antagonists

Talk about these different types of medications with your doctor.