Hypertension: common, dangerous and still poorly controlled

One day, Sam collapsed at work with a stroke that paralysed the left side of his body.

Sam was a well-known figure in the anaesthesia department. He was our administrator, central to the daily functioning of the place, in his early 40s and in the prime of life.

After his stroke, months of hospitalisation and rehabilitation followed. Sam recovered enough to return to his job but the man limping around campus with a walking aid was thin and frail, a much-diminished version of his former self.

Sam had been diagnosed with high blood pressure years earlier and was prescribed treatment. Unfortunately, he had not followed through. Partly it was denial. Distrust of the healthcare system also played a role. Despite being a healthcare worker himself, he had set the problem aside, until the day it arrived uninvited back into his life.

Sam’s hypertension was not rare or mysterious. It was the common kind, recognised in time, with treatment available. His story reminds us that effective management of hypertension is not only about diagnosis and prescribing. It is about whether people understand the risk, start treatment when needed, make realistic life changes, have trust, and stay connected to care for long enough to prevent catastrophic harm.

This series is about that larger problem: how health systems can manage hypertension at scale, improve outcomes and reduce the enormous burden of cost, disability and death that results from this common condition.

The burden of hypertension

A small group of chronic conditions accounts for much of the long-term burden of disease globally and in South Africa. Cardiovascular disease, stroke, diabetes, kidney disease and heart failure drive hospital admissions, disability, cost and premature death. Hypertension is at the centre of this cluster, contributing substantially to stroke, heart attack, heart failure and kidney failure, often alongside obesity, abnormal lipids, diabetes and other later-life multimorbidity. ^[2,4,5]

Globally, hypertension affects about 1.4 billion adults aged 30 to 79 years. Around 600 million are unaware that they have it, and only about one in five have it controlled. Raised blood pressure is one of the major risk factors for death and disability, killing over 10 million people each year. ^[1,9]

In South Africa, the burden is also large. Raised blood pressure accounts for about 12% of all deaths and is a major driver of stroke, hypertensive heart disease and ischaemic heart disease. Depending on the population studied and the method used, between about a third and nearly one-half of adults have hypertension. In the insured sector, new diagnoses among members aged 25–39 have been rising about 5% each year. ^[2-5,7]

A manageable condition that causes avoidable harm

It may be surprising to note that in most cases hypertension is manageable without highly specialised or expensive medical care.

Most hypertension is primary hypertension: raised blood pressure without a single clear underlying cause, usually arising from a mix of genetic, metabolic, behavioural and age-related factors. Only about 5-10% of patients have secondary hypertension caused by an underlying condition or medication. These patients need to be recognised and their care escalated appropriately. ^[6]

One reason hypertension is so dangerous is that it is usually silent at first. People are outwardly well. There is little sense of immediate danger. Consequences appear only years later, when uncontrolled blood pressure has damaged the brain, heart, kidneys or blood vessels. ^[1,6]

• Compared with many other major diseases, however, there is relatively little scientific uncertainty. Blood pressure is easy and inexpensive to measure. Effective, affordable medication has been available for decades. Treatment can usually be started simply and adjusted over time. ^[1,6] Effective lifestyle measures are known (see below), and clinical targets are reasonably clear. ^[1,6,8]

The real problem is that healthcare systems do not reliably move people from risk and diagnosis to long-term control.

Lifestyle change is part of both prevention and treatment of hypertension.

Salt reduction, weight loss where appropriate, regular physical activity, reduced alcohol intake, smoking cessation, better sleep and broader metabolic health can all help reduce risk. Dietary approaches such as a low-salt, high-fibre, fruit-and-vegetable-rich pattern are part of good hypertension care.

Patient education and family support are also important. People are more likely to accept and persist with treatment when they understand what hypertension is, why it matters, and what they can do about it. ^[6,8]

A cost-of-poor-quality problem

On the surface, the hypertension care system may appear to be functioning well. Diagnosis are made, prescriptions are written, benefits are paid and consultations take place. Failures become visible only later, when undiagnosed or poorly controlled blood pressure ends in stroke, heart failure, kidney failure, disability, lost income and avoidable suffering.

Hypertension should therefore be understood as a “cost-of-poor-quality” problem.

Better control no longer depends on future advances. It’s about doing ordinary things consistently well: identifying elevated blood pressure early, confirming the diagnosis, starting treatment when indicated, supporting lifestyle change and long-term adherence, checking whether control has been achieved, and recognising when routine care is no longer sufficient.

That makes hypertension a useful test of health-system performance. A system that manages it well probably does other things well too: identifying risk, supporting prevention, organising primary care for continuity, using data for follow-up, managing multimorbidity and escalating care appropriately when needed.

Conversely, a system that performs poorly on hypertension is likely to underperform across chronic disease more broadly.

Why this matters for South Africa’s private sector

In South Africa, the burden of hypertension and other poorly controlled chronic disease is high, and the consequences are visible in cardiovascular and renal illness.

In the better-resourced private sector, one would expect earlier detection, more reliable follow-up and higher levels of long-term control. Access to funding, medicines, clinicians and diagnostics should make that more achievable. But resources do not automatically become results. A better-resourced system achieves little if people are not reached, informed, supported and followed up over time.

The question is whether the advantages add up to a true hypertension control system: one that can identify the hypertensive population, detect emerging risk before disease is established, distinguish controlled from uncontrolled disease, support lifestyle and treatment adherence, and sustain follow-up over time.

That is the subject of the next article.

References

[1] World Health Organization. Hypertension fact sheet. https://www.who.int/news-room/fact-sheets/detail/hypertension

[2] Peer N, et al. National analyses of hypertension prevalence in South Africa. https://www.sciencedirect.com/science/article/pii/S2590113321000171

[3] Nojilana B, Bradshaw D, Pillay-van Wyk V, et al. Estimating the changing burden of disease attributable to high systolic blood pressure in South Africa for 2000, 2006 and 2012. S Afr Med J. 2022. https://samajournals.co.za/index.php/samj/article/view/219 https://www.ajol.info/index.php/samj/article/view/233870/220883

[4] National Department of Health, Statistics South Africa, SAMRC, ICF. South Africa Demographic and Health Survey 2016. https://dhsprogram.com/pubs/pdf/FR337/FR337.pdf

[5] Bradshaw D, et al. Second Comparative Risk Assessment for South Africa. S Afr Med J 2022;112(8b):556-570. https://doi.org/10.7196/SAMJ.2022.v112i8b.16648

[6] National Department of Health. National User Guide on the Prevention and Treatment of Hypertension. https://knowledgehub.health.gov.za/system/files/elibdownloads/2023-04/HYPERTENSION%2520USER%2520GUIDE%2520FINAL%2520COPY.pdf

[7] Discovery Health Medical Scheme notes an increase in young people diagnosed with chronic high blood pressure (hypertension). Press release. https://www.mynewsdesk.com/za/discovery-holdings-ltd/pressreleases/discovery-health-medical-scheme-notes-an-increase-in-young-people-diagnosed-with-chronic-high-blood-pressure-hypertension-3322821

[8] 2025 AHA/ACC Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. JACC Volume 86, Number 18