Silent Epidemic: Two-Thirds of Adults With High Blood Pressure Remain Unaware

High blood pressure has long been described by doctors as a silent killer, but a new analysis of nearly 1.4 million adults in England suggests the silence is deeper than many clinicians feared. Researchers at Oxford Population Health, drawing on clinic blood pressure measurements collected by Our Future Health, the United Kingdom’s largest health research programme, found that almost two-thirds of adults with hypertension had never been diagnosed and were not taking any medication to lower it. The study, published in BMJ Public Health, offers one of the most detailed portraits yet of how hypertension is detected, treated and controlled across a modern, diverse population, and the picture it paints is stark.

The research team analysed data from participants who enrolled in Our Future Health between 2022 and 2025. Hypertension was defined according to World Health Organization criteria: a systolic blood pressure of 140 mmHg or greater, a diastolic blood pressure of 90 mmHg or greater, or the use of blood pressure-lowering medication. Using this standardised definition, the investigators assessed three linked questions: how many participants had high blood pressure, how many of those had been diagnosed and treated, and how many had their blood pressure actually brought under control. The answers reveal a cascade of missed opportunities running through every stage of care.

Overall, just over one-third of participants, 37 percent, had hypertension. That figure varied enormously with age, rising from around one in six people aged 18 to 39 to nearly three-quarters of those aged 80 or older. After age-standardisation, hypertension was almost 50 percent more common in men than in women, affecting 42 percent of men compared with 29 percent of women. These prevalence estimates alone are striking, but the more alarming numbers concern what happened next. For 59 percent of people with hypertension, the condition was undetected: they had never received a diagnosis and were not on any blood pressure-lowering medication.

Detection, however, is only the first hurdle. Among participants who were taking one or more blood pressure medications, half still had elevated readings of 140/90 mmHg or higher. In other words, even when the healthcare system succeeded in identifying hypertension and initiating treatment, it frequently failed to finish the job. Effective hypertension management typically requires titration of drug doses, combination therapy, adherence support and regular monitoring, and the data suggest that these follow-through steps are breaking down for a large share of treated patients. The result is a population in which millions of people carry a major, modifiable cardiovascular risk without knowing it, and many of those who do know remain inadequately protected.

The clinical stakes are difficult to overstate. Hypertension is one of the most important causes of stroke, heart disease and premature death, and, as the British Heart Foundation emphasises, it remains the leading modifiable risk factor for cardiovascular disease, linked to around half of heart attacks and strokes in the United Kingdom. Because elevated blood pressure usually produces no symptoms, the first manifestation for many patients is a catastrophic vascular event. Every undetected case represents a person whose risk could have been reduced, often substantially, with timely diagnosis and appropriate treatment. Professor Bryan Williams, Chief Scientific and Medical Officer at the British Heart Foundation, described the study as painting a concerning picture of the scale of undetected high blood pressure and of the challenge of keeping the condition controlled in those already on treatment.

Perhaps the most provocative aspect of the analysis is the authors’ argument that the problem is not simply one of resources or public awareness, but of clinical policy. Despite longstanding guidance, current estimates of hypertension awareness, treatment and control in England have not improved in recent decades. The researchers contend that current National Institute for Health and Care Excellence guidelines, which require multiple confirmatory blood pressure readings before a diagnosis is confirmed and recommend lifestyle advice ahead of drug treatment, contribute to many cases never being properly detected, treated or controlled. Each additional diagnostic hurdle, the argument runs, creates another point at which a patient can be lost to follow-up, and each delay in pharmacological intervention extends the period during which quietly damaging blood pressure levels go unaddressed.

Wenyu Liu, Medical Statistician at Oxford Population Health and lead author of the study, was blunt in her assessment. While hypertension is largely a silent killer, she said, the current approach to detecting and treating high blood pressure is not fit for purpose. She stressed that the problem is not confined to any particular demographic group but is substantial across almost every category the team examined. Even among younger adults, who are not currently eligible for the NHS Health Check programme, more than 15 percent already had high blood pressure. That finding, she argued, underscores the need for population-wide prevention strategies alongside targeted treatment for people at high cardiovascular risk, rather than relying solely on age-triggered screening.

Clinicians working on the front line say the findings mirror everyday reality in general practice. Iain Turnbull, Deputy Chief Medical Officer at Our Future Health, Clinical Research Fellow at Oxford Population Health and a working GP, noted that many patients with high blood pressure are undetected or sub-optimally treated, and that the study’s results reflect what doctors see day to day. He called for a more proactive approach to detection and suggested that treatment decisions should consider predicted cardiovascular risk in addition to measured blood pressure levels. Such a risk-based strategy would echo approaches used in cardiovascular prevention more broadly, where absolute risk calculators help determine who benefits most from intervention, rather than waiting for a single measurement to cross a fixed threshold.

The scale of the dataset lends unusual weight to these conclusions. Our Future Health is designed to recruit up to five million people and to reflect the diversity of the UK population, collecting and linking multiple sources of health information, including genetic data, within secure, accredited trusted research environments from which identifiable information is removed and stored separately. Standardised clinic blood pressure measurements taken at enrolment, rather than self-reported diagnoses, mean the study captures the true prevalence of hypertension rather than the smaller fraction known to the health system. That methodological strength is precisely what allows the researchers to quantify the detection gap so confidently, and it explains why the findings have resonated across the cardiology and public health communities.

What happens next will depend on whether the health system can translate these numbers into action. The options under discussion include broader and earlier screening, simplified diagnostic pathways that reduce the number of confirmatory visits required, greater use of community and pharmacy-based measurement, and treatment algorithms that weigh overall cardiovascular risk rather than blood pressure readings alone. The British Heart Foundation estimates that better detection and treatment could help tens of thousands of people avoid preventable heart attacks and strokes, but achieving that, Williams cautioned, will require rethinking how at-risk people are identified, treated and supported so that blood pressure checks and effective therapy reach everyone. With hypertension implicated in roughly half of the UK’s heart attacks and strokes, and with the majority of cases still slipping through undetected, the study stands as a data-driven warning that one of medicine’s oldest and simplest interventions is being delivered to far too few of the people who need it.

Subject of Research: Prevalence, detection, treatment and control of hypertension among adults in England

Article Title: Two-thirds of adults with high blood pressure do not know they have it

Article References: Two-thirds of adults with high blood pressure do not know they have it. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: hypertension, blood pressure, cardiovascular disease, Our Future Health, Oxford Population Health, screening, NICE guidelines, public health, stroke, heart disease, BMJ Public Health, England