High blood pressure, also known as hypertension, is a symptomless condition which often results in cerebrovascular accidents, heart disease, and renal failure. Hypertension among adults is defined as a blood pressure greater or equal to 140 over 90 mmHg. 1 in 8 people in South Africa have hypertension.
Blood pressure is defined as the pressure of blood exerted against the inner walls of the blood vessels, and the force that keeps blood circulating continuously even between heartbeats. Two measurements are used to measure blood pressure: Systolic pressure which is the measure of blood pressure exerted when your heart beats and forces blood around your body, and Diastolic pressure which is the measure of blood pressure when your heart is resting in between beats. Both the systolic and diastolic pressures are measured in millimetres of mercury (mmHg).
Complications of Hypertension
Your heart pumps blood to your entire body. Uncontrolled high blood pressure can damage your heart in a number of ways, such as:
- Coronary artery disease-Coronary artery disease affects the arteries that supply blood to your heart muscle. Arteries narrowed by coronary artery disease don’t allow blood to flow freely through your arteries. When blood can’t flow freely to your heart, you can experience chest pain, a heart attack or irregular heart rhythms (arrhythmias).
- Enlarged left heart-High blood pressure forces your heart to work harder than necessary in order to pump blood to the rest of your body. This causes the left ventricle to thicken or stiffen (left ventricular hypertrophy). These changes limit the ventricle’s ability to pump blood to your body. This condition increases your risk of heart attack, heart failure and sudden cardiac death.
- Heart failure-Over time, the strain on your heart caused by high blood pressure can cause your heart muscle to weaken and work less efficiently. Eventually, your overwhelmed heart simply begins to wear out and fail. Damage from heart attacks adds to this problem.
Just like your heart, your brain depends on a nourishing blood supply to work properly and survive. But high blood pressure can cause several problems, including:
- Transient ischemic attack (TIA)-Sometimes called a mini-stroke, a transient ischemic attack is a brief, temporary disruption of blood supply to your brain. It’s often caused by atherosclerosis or a blood clot, both of which can arise from high blood pressure. A transient ischemic attack is often a warning that you’re at risk of a full-blown stroke.
- Stroke-A stroke occurs when part of your brain is deprived of oxygen and nutrients, causing brain cells to die. Uncontrolled high blood pressure can lead to stroke by damaging and weakening your brain’s blood vessels, causing them to narrow, rupture or leak. High blood pressure can also cause blood clots to form in the arteries leading to your brain, blocking blood flow and potentially causing a stroke.
Your kidneys filter excess fluid and waste from your blood, a process that depends on healthy blood vessels. High blood pressure can injure both the blood vessels in and leading to your kidneys, causing several types of kidney disease (nephropathy). Having diabetes in addition to high blood pressure can worsen the damage.
Causes of Hypertension
The exact causes of high blood pressure are not known, but several things may play a role, including:
- Being overweight or obese
- Lack of physical activity
- Too much salt in diet
- Too much alcohol consumption
- Older age
- Chronic kidney disease
- Adrenal and thyroid disorders
- Sleep apnea
Management and medications
Some of the risk factors for high blood pressure cannot be controlled, such as your family history and age. But you can take steps to lower your risk by changing factors you can control. Antihypertensive therapy plays a key role in controlling blood pressure as well as reduces cardiovascular and renal morbidity and mortality. The aim of antihypertensive therapy can be achieved through lifestyle modifications alone, or in combination with pharmacological treatment. The most common pharmacological treatment include beta blockers, ACE inhibitors, diuretics, ARBs, as well as calcium channel blockers, all of which play a role in controlling blood pressure.
Non pharmacological recommendations for controlling high blood pressure involve the following:
- Quit smoking
- Decrease alcohol consumption
- Reduce weight
- Ingest adequate amounts of potassium, calcium and magnesium
- Modify diet
- Be physically active, at least 20-30 minutes a day
Exercise and blood pressure
The benefits of regular exercise involve improvement in cardiovascular and respiratory function, reduction in the risk for heart disease, decrease in mortality and morbidity, as well as other postulated benefits such as decreased anxiety and depression, as well as a feeling of well-being.
A single session of exercise at an intensity of 50% – 100% VO2max produces a lowering of 18-20mmHg in systolic and 7-9mmHg in diastolic. These changes remain for 12 to 16 hours after exercise. In addition, losing up to 3 kg in body mass lowers blood pressure by 7/4 mmHg.
High blood pressure is a common condition that increases the risk for cardiovascular disease, especially coronary artery disease and stroke. However, the condition can be managed through antihypertensive therapy which includes lifestyle modifications and the use of pharmacological treatment. Thus, by making certain lifestyle modifications, one can finally put an end to this silent killer.
To find out more about what you can do to treat this condition please Contact Us for an assessment.
Author: Taariq Patel at Fish and Field Biokineticists
Durstine, J.L., Moore, G.E. & Painter, P.L., 2016. ACSMs exercise management for persons with chronic diseases and disabilities, Human Kinetics.
Pal S, Radavelli S, Ho S (2013) ‘potential benefits of exercise on blood pressure and vascular function’, J Am Soc Hypertens, 7(6), pp. 494-506.