All you need to know about hypertension

DR MAXWELL ADEYEMI

HYPERTENSION IS common in many people, especially in people of African descent, wherever they reside. Despite the availability of a wide variety of antihypertensive drugs, poorly controlled hypertension is the single largest risk factor for organ damage. This is not just a consequence of socio-economic deprivation, because even in countries that subsidise medications, hypertension control rates remain poor.

What is blood pressure

Blood pressure (BP) is the pressure of the blood against the walls of the arteries when the heart pumps blood into the arteries. Normal blood pressure is below 120/80 mmHg. The top number (systolic) is the pressure when the heart contracts to pump blood into the arteries, and the bottom number (diastolic) is the pressure when the heart relaxes between beats. Both numbers are equally important. When blood pressure is high and untreated, it can damage blood vessels in various organs in the body.

What are the types

of hypertension

There are two types of hypertension. Primary hypertension – also known as essential hypertension – refers to hypertension that has no known cause. Over 90 per cent of people who have hypertension have primary hypertension.

Secondary hypertension is when there is an identifiable and potentially reversible cause of hypertension. Less than ten per cent of hypertension is the secondary type and it is more prevalent in younger people. Some of the causes of secondary hypertension include high levels of hormones that control blood pressure, narrowing of arteries that supply blood to the kidneys, side effects of medications like birth control pills and diet pills.

Why is hypertension common

in people of African descent?

Researchers don’t have a definitive explanation, but it may be due to genetic factors. It has been theoried that people of African descent possess a gene – a thrifty gene for sodium – that enabled their kidneys to excessively reabsorb and conserve sodium in the hot, dry climate of Africa to avoid dehydration.

However, as people migrated out of Africa to cooler climates, they carried this gene with them, resulting in sodium avidity that leads to hypertension, especially in societies where salt is abundant in foods.

Also, research shows that there may be a gene that makes people of African descent more salt sensitive. In people who have this gene, as little as half a teaspoon of salt could raise blood pressure by 5 mmHg. Furthermore, even among people of African descent with normal blood pressure, when given an equivalent amount of salt, their blood pressure rises higher, and their body retains more of the administered salt compared to white people.

Harmful effects

of hypertension

Hypertension usually has no symptoms. Organ damage goes on quietly without the individual having any symptoms (silent killer), until a catastrophic event occurs. Hypertension may cause heart failure, stroke, heart attack, kidney failure, abnormal heart rhythm, eye disease, erectile dysfunction and death.

Treatment of hypertension

Broadly there are two approaches to treat hypertension and both are complementary to each other. Your doctor decides on what drug is ideal for you based on factors like cost, side effects, gender, age and any coexistent conditions like diabetes, heart failure or prostate enlargement.

Non-drug therapy of hypertension (also called lifestyle modification) involves the implementation of the following interventions:

1. Dietary salt restriction

2. Maintaining ideal weight

3. Aerobic exercise

4. Reducing alcohol intake

5. DASH (dietary approaches to stop hypertension) diet – which consists of increased intake of fruits, vegetables, low-fat dairy products combined with salt restriction

6. Smoking cessation, adequate potassium intake, avoidance of non-steroidal anti-inflammatory drugs

7. Good sleep hygiene

8. Vitamin D supplementation in those with vitamin D deficiency

Treatment of hypertension

Proper treatment of hypertension significantly reduces the risk of organ damage. However, proper treatment of hypertension
must include non-drug therapy. Failure to aggressively employ the above-listed “lifestyle modifications” is the most important explanation for why a large proportion of treated hypertensive patients fail to achieve the desired BP.

This is because the ability of antihypertensive drugs to normalise your BP long-term is dependent on strict adherence to the “lifestyle modifications.” For example, even if you achieve normal blood pressure initially by taking multiple blood pressure medications, and you fail to simultaneously reduce salt intake, after a while your BP will begin to rise again.

The effectiveness of non-drug interventions is well established, but the challenge is that doctors don’t emphasise them enough, and many patients lack the discipline to stick to them. Therefore, it becomes rather convenient to just prescribe drugs.

Other measures that will improve hypertension control is to appreciate that in people with moderate to severe hypertension, no single drug covers for 24 hours – stagger treatment throughout the day to achieve round-the-clock coverage.

Also, in people with moderate to severe hypertension and in people of African descent, a diuretic (water pill) is essential to enhance salt excretion – especially since the body reflexly begins to retain salt after the initial lowering of blood pressure with drugs.

Common myths

in hypertension

“I took a course of pressure medications for two weeks.” This is erroneous as high blood pressure is not an infection that you treat for a week or two as you can do with antibiotics. Once you have hypertension, it’s a lifelong thing most times that have to be treated and monitored.

“I can’t have hypertension because there is nothing I am thinking about or nothing is bothering me.” Thinking or being bothered by something is not the issue – hypertension is very common in people of African descent.

“My blood pressure is not high because I don’t have any symptoms.” In general, there are no symptoms attributable to hypertension – you will have symptoms once it has damaged your organs.

“I usually know when my blood pressure goes up as I feel tension in my neck or get headaches.” This is not always so, as you may feel tension because of other reasons, and your pressure may be high and you don’t feel anything.

Primary hypertension is a lifelong condition, so most patients will need blood pressure control for life. However, achievement of normal blood pressure by strict adherence to lifestyle modification measures would permit reduction in the number or dose, or, infrequently, discontinuation of antihypertensive drugs.

Meticulous adherence to lifestyle modifications to control hypertension is not just effective, but also saves money by reducing the number or dose of antihypertensive medications that the individual requires. While individuals are ultimately responsible for adherence to lifestyle modification measures, many countries are implementing policies at the national level to combat hypertension.

Countries that have implemented a hypertension awareness initiative, reduction of salt intake strategy and aerobic exercise by prescription programme at a national level have witnessed a dramatic improvement in blood pressure control, as well as a remarkable reduction in organ damage and deaths from hypertension.

Consult with your doctor to effectively manage your blood pressure.

Contact Dr Maxwell on 3631807 or 7575411