Blood pressure is the measure of the force exerted by blood as it travels through the blood vessels after the heart has pumped it.
If you have had your blood pressure taken, you may have seen it recorded as two numbers. The numbers are the systolic blood pressure over the diastolic pressure. The systolic blood pressure is that pressure when the heart beats while the diastolic pressure is the pressure in the blood vessels when the heart rests. The normal blood pressure is considered to be between 90/60 to 120/80 mmHg.
The Kenya National Guidelines for Cardiovascular Diseases Management defines high blood pressure (hypertension) as persistently elevated blood pressure of 140/90 mmHg or more.
Why is increased blood pressure a problem?
Well, an increase in the blood pressure above the normal range in adults has been shown to cause an increase in the risk of developing cardiovascular diseases, stroke and kidney disease. What’s more, the risk of death from heart and blood vessels disease (cardiovascular disease) doubles with every 20mmhg rise in systolic and 10mmhg rise in diastolic blood pressure above the normal levels.
Hypertension in Kenya
In the 2015 Kenya STEPS survey, 24 in 100 Kenyans had hypertension with only 8% of them on treatment for the disease. Only half of those on treatment had their pressure well controlled. In addition to low access to treatment and control levels, awareness levels were also low. The survey showed that more than half of Kenyans have never been screened for hypertension.
Takeaway: Did you know it is recommended that you get your blood pressure measured annually if you are above 40 years, and every three years if you are aged between 18-39 years?
Globally, 1 in 4 men and 1 in 5 women suffer from hypertension.
Types of hypertension
Hypertension is broadly classified into Primary (Essential) and Secondary (Non-essential) hypertension depending on its causes.
This comprises 95% of all diagnosed cases in adults.
The causes of this type of hypertension are not known. It is also called Essential hypertension. However, the following risk factors have been identified as contributing to disease development:
- Increasing age above 45 years in men and 60 years in women
- Family history of hypertension
- Overweight/central obesity
- Physical inactivity
- Tobacco use
- Low intake of fruits and vegetables
- High dietary salt
- Low dietary potassium
- Low vitamin D
- Chronic alcohol use
This accounts for 5% of the cases. The specific causes for the elevated pressures can be identified. The hypertension is thus said to be secondary to the identified cause.
These causes include:
- Narrowing of the kidney arteries
- Diseases of the kidney
- Coarctation of the aorta
- Disorders of the thyroid gland
- Tumour or Excess secretion from the adrenal gland
- Cushing’s syndrome
- Obstructive sleep apnoea
“The Silent Killer”
Hypertension develops slowly over time and has no tell-tale symptoms. Its complications sneak up on individuals, earning the name “silent killer”.
The symptoms occur when the pressures are highly elevated and may include: headaches, dizziness, blurred vision, nose bleeding, vomiting, fatigue, chest pain and muscle tremors.
Hypertension is diagnosed with accurate blood pressure measurement. A cuff is applied to the upper arm, inflated and then deflated slowly and the blood pressure readings recorded.
Other tests are done to assess any organ damage and other co-existing conditions. These include urinalysis, blood glucose levels, lipid profile test and blood count tests,
In the Kenya National Guidelines for Cardiovascular Diseases and Management, the overall aim in the treatment of hypertension is the adequate control of blood pressure. This will prevent complications and death from the disease. Hypertension is unfortunately not curable but can be controlled.
- Lifestyle modification
This can reduce one’s blood pressure, risk of cardiovascular death and number of antihypertensive medication is given. These lifestyle changes include: limiting alcohol intake, stopping tobacco intake, daily moderate-intensity exercise, consumption of a healthy diet (DASH- diet) and weight reduction in obese patients.
A medical practitioner will give medicine to treat hypertension according to the treatment guidelines. The antihypertensive medications act in different mechanisms such as widening the blood vessels and reducing blood volume through water loss by the kidneys.
Hypertension complications are severe, causing disability and premature death.
Uncontrolled hypertension causes damage to the heart muscle, hardening of arteries, and increased risk of atherosclerosis. These decrease blood flow to the heart, causing chest pain, heart failure, heart attack and irregular heartbeat (arrhythmia).
It causes damage to the:
- kidneys, resulting in kidney failure.
- Eyes blood vessels cause visual problems and blindness.
- Blood vessels in the brain. These burst or block, causing a stroke.
- Arterial walls, weakening them leading to aneurysms.
You can reduce your risk of developing hypertension by living a healthy lifestyle and ensuring you have regular blood pressure measurements to catch it early.
If you are diagnosed with hypertension, adhere to your prescription and lifestyle advice, monitor your blood pressure at home and attend your medical clinic regularly.