Silent killer: study finds most with high blood pressure unaware

A recent British study involving around 1.4 million people in England has found that more than a third of adults have high blood pressure. ADVERTISEMENT ADVERTISEMENT Worryingly, the study shows that around 6 in every 10 people affected, 59%, do not know they are living with this "silent killer" and have not received any treatment. These figures highlight a persistent failure to detect one of the main risk factors leading to heart and vascular disease and strokes, amid growing calls from health experts to step up early screening campaigns and save millions of people at risk of deadly complications. A marked rise with age Researchers from the Population Health Department at the University of Oxford analysed blood pressure readings taken in clinics as part of the "Our Future Health" programme, the largest health research initiative in the United Kingdom. The data covered participants who joined the programme between 2022 and 2025. The study used World Health Organization criteria to define high blood pressure, classifying someone as hypertensive if their systolic reading is 140 millimetres of mercury or above, their diastolic reading is 90 millimetres of mercury or above, or if they are already taking blood-pressure-lowering medication. The data showed a large variation in prevalence by age: 15% among adults aged 18 to 39, rising gradually to 71% in people aged 80 and over. Men were more likely than women to have the condition, with rates of 42% for men compared with 29% for women, after adjusting for age groups. Half of those on treatment do not reach the target level The problem does not only concern undiagnosed cases. The study found that 50% of participants taking one or more medicines to lower blood pressure still had readings of 140/90 millimetres of mercury or above, the threshold used in the research to define high blood pressure. According to the researchers, these findings show that difficulties in diagnosing and controlling the condition in England persist, despite clinical guidelines that have been in place for years. They pointed out that current guidance from the National Institute for Health and Care Excellence (NICE) requires several measurements before confirming a diagnosis and, in some cases, recommends starting with lifestyle changes before prescribing medication. They believe this approach may be leaving some cases without detection or effective treatment. Calls for a more proactive approach Wenyu Liu, a medical statistician in the Population Health Department at the University of Oxford and lead researcher on the study, said high blood pressure is often described as a "silent killer", arguing that the current methods of detecting and treating the condition need to be reconsidered. Liu stressed that the "silent killer" crisis is not confined to older people, noting that more than 15% of younger adults aged 18 to 39 were found to have high blood pressure. She noted that this younger group currently falls outside routine medical monitoring, as they do not meet the age criteria for the National Health Service (NHS) regular health check programme, which starts at 40. This, she said, makes an urgent update of early detection policies necessary. Liu called for stronger population-wide prevention strategies, alongside directing treatment towards those most at risk of heart disease and other cardiovascular conditions. For his part, Ian Turnbull, deputy chief medical officer for the "Our Future Health" programme, clinical researcher in Oxford University's Population Health Department and a general practitioner, said the results are in line with what doctors see in general practice, where many cases of high blood pressure remain undetected or are not treated optimally. He highlighted the need for a more active approach to finding people with the condition, including examining whether treatment should start on the basis of an individual's predicted risk of heart and vascular disease, rather than relying solely on blood pressure levels. British Heart Foundation warns of missed chances for prevention Professor Bryan Williams, chief scientific and medical officer at the British Heart Foundation, described the study's findings as worrying, saying they reveal the scale of undiagnosed high blood pressure and the difficulties in controlling it among people who are already receiving treatment. Williams said high blood pressure remains the main modifiable risk factor associated with cardiovascular disease, noting that it is linked to around half of all heart attacks and strokes in the United Kingdom. He added that millions of people are living with the condition without knowing it, which means important opportunities for diagnosis and early intervention are being missed. According to Williams, improving the detection and treatment of high blood pressure could help tens of thousands of people avoid preventable heart attacks and strokes. However, he believes this will require a rethink of how people at risk are identified, treated and followed up, to ensure blood pressure checks and effective therapy reach all groups.