Hypertension: The killer within that we’re oblivious of

Mohammed Ismail* was messing around with his father’s blood pressure machine when he made a discovery that shocked him: his own blood pressure was sky-high. Neither overweight nor unfit, Ismail has always been careful to eat healthily. When he consulted a doctor, he was told that his hypertension was probably hereditary, lethally ticking away undetected in his outwardly healthy body.

Almost half of all South Africa adults have high blood pressure but most are unaware of this until they develop serious health issues – particularly strokes and heart disease.

“About 73% of people living in sub-Saharan Africa are not aware that they have hypertension. That is why it is called the silent killer,” said cardiologist Dr Martin Mpe, who is president of the South African Hypertension Society.

Worse still, even once people have been diagnosed with hypertension, the majority do not have their blood pressure under control – in part because medical experts still don’t know which medicine is the best to treat people from Africa, China and South Asia.

For over two decades, Nombulelo Mzwakali battled to control her blood pressure. The various doctors that she saw in the public health system prescribed different drugs and told her to lose weight. But neither strategy worked. When she was in her early 60s, she had a debilitating stroke that impaired her speech and motion, followed by a second stroke a year later that killed her.

“In South Africa, only about 6 to 8% of people with hypertension have their condition under control,” according to Mpe, who was speaking at a media round table ahead of the World Congress of Internal Medicine in Cape Town.

Hypertension is the main cause of strokes and heart attacks, but it also plays a role in other conditions such as kidney disease, sexual dysfunction and dementia. More than 10-million people a year die of hypertension-related diseases, making it the biggest epidemic known to humanity (tuberculosis kills around 1,2 million people a year).

“Nothing kills as effectively as high blood pressure. High blood pressure is the single biggest contributor to the global burden of disease and death,” according to Professor Neil Poulter, head of Preventive Cardiovascular Medicine at Imperial College London and immediate past president of the International Society of Hypertension.

Monday, 29 October is World Stroke Awareness Day, and the SA Heart and Stroke Foundation tells us that about 360 South Africans have strokes every day, causing 110 to die and 90 others to become disabled.

Governments worldwide have been slow to act against hypertension, perhaps because it has been associated with old people with little agency,

“Only a third of those on hypertensive treatment have their condition controlled because they are not on the right drugs. People need two drugs, but which two varies according to ethnic group,” said Poulter.

“We don’t have data about what treatment works best for people from Africa, south Asia and China. It is an indictment on the international hypertension community that we only have data about what works for whites.”

A big study – called the CREOLE trial - is under way to test three different drug combinations to find out which is the most effective for African patients. Patients from South Africa, Cameroun, Kenya, Mozambique, Nigeria and Uganda are involved and the results will be released in 2019.

“South Africa has seen an exponential growth in hypertension over the last 20 years,” says Professor Brian Rayner, director of the Hypertension Institute at the University of Cape Town. “It's a national health emergency, but because the links between high blood pressure and death, heart disease and stroke are indirect, public awareness is poor.”

Urging everyone to have annual blood pressure checks, Rayner said that it was a “myth” that people can feel their blood pressure: “If your blood pressure is very low, you might fall down and faint and if it is very high, you might get a head ache. But the only way to know if you have high blood pressure is to have it tested.”

It is easier to find a South African over the age of 45 with hypertension than someone with normal blood pressure (63% of women and 55% of men have hypertension by this age). But those with the condition are getting younger and younger.

One in five high school children already have high blood pressure, according to Professor Alta Schutte, director of the Medical Research Council’s Unit for Hypertension and Cardiovascular Disease.

“The main drivers of hypertension in South Africa are abdominal obesity, alcohol and high salt intake,” said Schutte, who is also the president of the International Society of Hypertension.

She said that a recent study followed South Africans with normal blood pressure for five years and that, during this time, a quarter of them developed high blood pressure.

“Awareness is not enough to get people to change their behaviour. We need government intervention to change the food industry,” said Schutte, adding that the tax on sugary drinks was a good start.

“Governments need to work with the food industry to cut down [the salt and sugar] in food,” said Poulter. “But the problem is that many of the big food companies also own sugary drinks companies. If they lower the salt content, people won’t get as thirsty and drink their fizzy drinks.

“Often you can’t tell where the salt is. A bowl of Corn Flakes has the salinity of salt water. Brown bread is also stuffed with salt. If you eat these two for breakfast, you might think you have eaten a healthy breakfast, but you have eaten about two days’ worth of salt,” said Poulter, adding that “fizzy drinks should be taxed out of sight”.

Between 1990 and 2020, deaths from heart attacks in the developing world are projected to jumped up 120 percent in women and 137 percent in men. Deaths from strokes are projected to more than double in women and increase by 124 percent in men over the same period.

For many years, South Africa’s public health sector has been single-mindedly focused on tuberculosis and HIV. But it is time that more attention is paid to the “silent epidemic” of hypertension and its deadly partners, strokes and heart attacks. DM

*Not his real name