Since 2005, The World Hypertension League (WHL) has promoted World Hypertension Day on 17 May, annually. The primary aim of this health event is to increase the awareness of the dangers of high blood pressure (BP) or Hypertension in populations around the world. The call to action for World Hypertension Day is to promote best practices to stay up to date with global standards in hypertension prevention, and measurement and to standardize these measures globally in order to monitor the prevalence within countries and across countries. Key stakeholders in the health space are set to achieve the goal for hypertension control in Africa by the year 2030.
In 2022 the focus is on low to middle income countries (LMICs) as the consequences of hypertension in these countries lead to very poor health outcomes, in particular making individuals more vulnerable to heart disease, strokes and other circulatory diseases. Given the rise in the prevalence of hypertension in LMICs over the past 25 years, interventions for hypertension control are urgently needed. 1 in 3 people are aware of their hypertension status with only approximately 8% of them having their blood pressure controlled. It has been projected that three quarters of all adults with hypertension will be living in LMICs by the year 2025.
As hypertension is the leading preventable risk factor for cardiovascular diseases in Africa and globally, it is important to stimulate all countries to address social impact, disease burden and costs for national health systems. Hypertension is responsible for 13% of all deaths globally. In South Africa more than 1 in 3 adults live with high blood pressure and it is responsible for 1 in every 2 strokes and 2 in every 5 heart attacks. High blood pressure is known as a ‘silent killer’ because there are rarely any symptoms or visible signs to warn that blood pressure is high. That is why more than 50% of people with high blood pressure are unaware of their condition.
Hypertension is defined as the high persistent force of the blood flowing through the blood vessels. Fluctuations in blood pressure are normal which is why it is only diagnosed when it remains high on several occasions or when it is dangerously high on one occasion.
It is important to understand the pathophysiology of hypertension as this will prove the urgency of appropriate action to address it.
When trying to understand the risk factors of hypertension in relation to LMICs, it is a combination of both risk factors that have already been well establihed and those that are not emphasized enough. Established risk factors include unhealthy diets which in LMICs can be associated with affordability and availability of healthy foods, as well as physical inactivity. Another prominent risk factor is tobacco smoking with over 80% of all tobacco users residing within LMICs. Further to this, excessive alcohol consumption has been linked to hypertension and heavy episodic drinking has been found to be high in LMICs. With LMICs facing a double burden of malnutrition (i.e. coexistence of undernutrition and overweight/obesity), obesity is another established risk factor which can lead to kidney disease which in turn, can increase blood pressure.
Less emphasized risk factors include environmental factors such as low green space, high pollution and urbanization, all which have a link to raised blood pressure and are found to be in a worse state in LMCIs compared to the rest of the world. Green space is found to reduce environmental stressors such as air pollution. This is necessary as polluted air can enter the bodily systems, resulting in arterial stiffness. Urbanization, which is at a rapid rate in LMICs, is an element that births all the above-mentioned established risk factors as well as the environmental factors. Another less emphasized yet highly driven risk factor for hypertension, especially in LMICs, includes social and commercial determinants of health. Social determinants refer to unequal conditions in which individuals are born, grow, live, work and age and often influence risk factors for hypertension, mainly unhealthy diet, physical inactivity and tobacco and alcohol consumption. Examples of commercial determinants of health, which are found to influence unhealthy behaviors such as tobacco smoking include certain industries that promote products harmful to health.
Familial hypertension (FH) is often also not discussed as an important risk factor. FH is a rare, genetic form of hypertension caused by mutations in particular genes, many of which help control the balance of fluids and salts in the body and affect blood pressure. The heritable component of blood pressure has been documented in familial and twin studies suggesting that 30%-50% of the variance of blood pressure readings are attributable to genetic heritability (explained by genes) and about 50% to environmental factors. Similarly, familial aggregation of hypertension is well recognised and a family history of hypertension has been associated with an increased risk and earlier onset of hypertension, highlighting the importance of genetic factors in hypertension.
Amongst the known risk factors, evidence states that the likelihood of high blood pressure increases with age. Nearly 8 in 10 South Africans over the age of 55 years have high blood pressure (The Heart and Stroke Foundation South Africa).The HSFSA, therefore, urges the public and especially those over the age of 45 years to get screened and know their numbers. Furthermore, our message stands simple and strong to adhere to medications prescribed by your doctor should you already be diagnosed. Below is a table which summarizes the readings taken when blood pressure is measured.
