What is Blood Pressure?
As the heart contracts, the pressure within the blood vessels rises to
a maximum, which is called the systolic blood pressure. When the heart
relaxes the blood pressure falls to a minimum or bottom blood pressure
called the diastolic blood pressure. Blood pressure is required to force
the blood to circulate throughout the body. The average systolic blood
pressure is about 120 mmHg and the average diastolic blood pressure is
about 80 mmHg (millimeters of mercury). This is reported as 120/80 or
120 over 80 mmHg. Elevations of blood pressure is present when the systolic
blood pressure is above 140 mmHg or the diastolic blood pressure is above
90 mmHg. The condition of having elevated blood pressure is called hypertension.
In the majority of patients with hypertension the cause cannot be found.
Genetics and heredity may play a role. In 5 to 10% of patients a reversible
cause for hypertension may be identified.
Environmental factors such as excess salt intake will raise someones
blood pressure. Other modifiable causes of hypertension include excessive
calorie intake, inactivity, excessive alcohol consumption, low potassium
intake and smoking. In fact eliminating fast food from the diet will lower
your blood pressure significantly.
Hypertension is common and present in about 10% of the adult population
or about 2 million people in Canada. For the most part patients with hypertension
are under-diagnosed and under treated. The Canadian Heart Health Survey
has shown that only 42% of patients are aware that they have hypertension,
of these, the majority are inadequately treated and only 16% of hypertensive
patients have their blood pressure adequately controlled.
What are the risks of high blood pressure?
Excessive elevation of blood pressure can have long term effects. High
blood pressure will thicken the heart muscle. This condition is called
hypertrophy. Elevated blood pressure can lead to stroke, vascular damage,
and kidney failure. For the most part high blood pressure has no associated
symptoms unless complications develop. If blood pressure is quite high
patients may experience headaches, fatigue, shortness of breath or dizziness.
High blood pressure is particularly dangerous in those patients with other
cardiac conditions such as coronary artery disease or leaking heart valves.
In conditions such as diabetes or hypertension it is especially important
to normalize blood pressure to prevent progressive kidney and organ damage.
High blood pressure in the elderly population is one of the major risk
factors for stroke.
Can high blood pressure be treated?
Yes. There are many medications that can be used to control blood pressure.
Often small doses of a diuretic or a beta blocker medication are sufficient.
In some patients combination therapy is required and in other patients
certain agents are used for special or specific reasons such as angiotensin
converting enzyme (ACE) inhibitors in diabetes and calcium channel blocking
agents in the elderly. Medical evidence shows that aggressive treatment
of blood pressure will reduce the risk of stroke and cardiovascular events
considerably. If you have further questions regarding hypertension please
discuss them with your physician.