Blood Pressure-101

Do you have high blood pressure? Though almost 15 percent of North America's population does, less than a third of them know it. As we age, our chances of getting high blood pressure increase. Over a lifetime the risk of having high blood pressure is 90 percent. Many people believe if they are relaxed and relatively stress free, they cannot possibly have high blood pressure. Sadly, this isn't true. It is also wrong to think that your blood pressure must be normal because you feel well.

Most people who learn their blood pressure is high have no symptoms and may not even be under much stress. You cannot tell what your blood pressure is based on how you feel. The only way to know your blood pressure is through direct measurement.

Your family doctor can measure your blood pressure for you. First, a fabric cuff is applied to your upper arm. An inflatable bladder inside the cuff is pumped up with air until the pressure in the balloon is higher than the pressure in the arteries of your arm. This feels tight but not painful. The person taking the measurement slowly lowers the pressure in the balloon and uses a stethoscope on the inside of your elbow to listen for blood beginning to enter the arm again.

The first measurement, systolic pressure, is equal to the pressure inside the bladder when the sound of blood first re-entering the arm is heard. The second reading, diastolic pressure, is taken when the pressure in the balloon drops low enough that it no longer compresses the artery. At this point no sound is heard.

These two numbers together are used to describe a person's blood pressure. Systolic pressure is always written first and is a higher number. For instance, if medical staff says your blood pressure is 120 (systolic) over 80 (diastolic), it will be written 120/80. This simple procedure provides valuable information about the state of a patient's arteries and the functioning of their heart.

Hypertension is the word used to describe high blood pressure. It does not indicate nervousness or being highly stressed. It simply means that the pressure at which blood is pumped from the heart to the various parts of the body is elevated. This is a serious and very common medical problem. Although an elevated blood pressure will not directly make you feel sick, it can have grave results on your health. Whether the pressure is high for many years or very high for a short time, health problems can occur. Stroke, heart attack, heart failure, circulatory problems in the limbs, kidney failure and early death are all more likely if you have high blood pressure. Even dementia has been recently linked with hypertension. The World Health Organization reported in 2002 that for North Americans, hypertension is the leading risk associated with death in women and the second leading risk in men!

When diagnosing high blood pressure, the doctor has four things to consider:

1. Is the pressure truly elevated?

2. Has the pressure damaged any body organs such as the heart, brain or kidney?

3. Are there other factors that could also damage the circulation such as smoking or diabetes?

4. Can a cause be found for the high blood pressure?

 

 

RECOMMENDED FOLLOW-UP OF BLOOD PRESSURE IN ADULTS
(U.S. Joint National Committee on High Blood Pressure)

 

 

TABLE 1

 

Initial Blood Pressure		Recommendation
Systolic	Diastolic
Under 120	Under 80	Recheck in two years
120-139	80-89	Diet and lifestyle modification recheck in 1 year
140-159	90-99	Diet and lifestyle modification recheck in 2 months
Over 160	Over 100	Manage within 2-4 weeks

 

 

Confirming that blood pressure is elevated is tricky. Blood pressure measurements vary a lot through the day with different activities. Several measurements and often-home measurements are needed to confirm elevation at all but the highest levels. (Blood pressure measured at home is expected to be below 135/85.) The level of blood pressure measurement will allow the doctor to assess the urgency of the problem (see table 1). The higher the blood pressure the greater the risk and the urgency.

 

 

HIGH BLOOD PRESSURE RISK
Risk Category	Systolic Pressure (mm Hg)	Diastolic Pressure (mm Hg)
Normal:	Under 120	Under 80
Pre-Hypertension:	120-139	Under 80
Hypertension:
Stage 1:	140-159	90-99
Stage 2:	Over 160	Over 100

 

 

If the systolic and diastolic pressures are in different risk categories, the higher risk category is chosen.

 

 

There are limits that have been chosen to mark the end of one risk level and the start of another. These levels do not mark sharp changes in risk since the danger gradually increases at any pressure above the ideal of 120/80. A blood pressure in the high end of the normal range (120/80 to 140/90) carries three times the risk of circulation problems such as stroke and heart failure. Despite the gradual increase in risk above 120/80 there is agreement about the pressure levels that are considered normal and abnormal (see Table 2).

The next step in evaluating high blood pressure is to look for evidence of damage to the brain, eyes, heart, and kidneys. The third question is whether other factors are present which increase a person's risk of developing complications from hypertension. To answer this question the doctor looks for factors such as diabetes, high cholesterol and cigarette smoking because they all further increase the danger of high blood pressure.

Finally, it is important to determine whether a cause for the high blood pressure can be found. Hypertension is classed as either essential (primary) or secondary. Ninety-five percent of cases are classed as essential hypertension because no cause can be found.

This type of hypertension usually first appears between the age of 30 and 50, and there is often a family of it. It is likely the result of many factors in combination. The other five percent of high blood pressure cases have a medical condition causing the pressure to be high. This is called secondary hypertension. It is more likely that a person has secondary hypertension when the blood pressure elevated before the age of 30 years of after 50.

 

Essential hypertension is responsible for the most of the complications of elevated blood pressure in our society. This condition is being studied in great detail. We are learning a great deal about how the body handles fluid, salt and calcium and how the nerves, reflexes, and chemicals interact to determine blood pressure. The effects of weight, exercise, alcohol, cigarettes, diet, and genetic factors also have an influence.

 

Secondary hypertension is important because the underlying cause often requires specific management. Doctors try to target both the cause and the hypertension itself. Common causes of secondary hypertension include sleep apnea, chronic kidney disease, narrowing of the arteries supplying the kidney, various benign tumours, thyroid disease, and certain drugs including birth control pills, anti-inflammatory medications and alcohol.

 

High blood pressure is treatable and the good news is that treatment can avert much potential damage. Safe blood pressure levels have been determined in studies involving tens of thousands of patients.

 

 

Treatment Targets

The recorded level of blood pressure will guide the doctor's next step in treatment (see tables 1 and 3). Recent studies have shown that anyone, including the elderly, can benefit from active management of hypertension. Despite this, only half of those people with known hypertension have their pressure adequately controlled. (see Table 4).

 

 

How can I help myself?

There are many things a person can and should do to reduce high blood pressure and its risks. Diet modification, exercise and weight loss can all help. If a person is over weight, losing just five kg (11 pounds) will noticeably lower the pressure. Exercise helps weight loss, reduces the risk of damage to the heart and improves well being- and can lower blood pressure. Simply walking for 20 to 45 minutes five times a week will improve health. Reducing salt, alcohol intake and eating a diet rich in calcium and potassium will also help significantly. Some believe that eating garlic and onion can decrease blood pressure. However, this has never been proven in a recognized clinical trial.

 

Although stress can raise blood pressure, stress management programs offer only small unreliable results. Still, relaxation training and bio-feedback remain important techniques in improving the quality of life for those under stress, whether or not they are hypertensive.

 

If your doctor feels your blood pressure it too high or if it remains high despite the general measures just outlined, medication may become necessary. Many medications can be used. Your doctor will try to pick the best way to control your blood pressure without unacceptable side effects. Fortunately, most patients are now able to use medications that are safe, lower blood pressure and have little or no side effects as ALISTROL.

 

If you have high blood pressure, it is very important that you know about it. Remember, a lack of symptoms does not mean your blood pressure is normal. See your doctor and have your pressure checked if you have not already done so. If a problem is discovered, follow your doctor's advice carefully. Proper treatment can prevent much of the terrible damage and suffering that can result from high blood pressure.