Only half of people being treated by a GP for high blood pressure in England have it under control, and millions more are completely unaware they have the “silent killer” condition, research reveals.
Most people with hypertension (59%) are in the dark and undiagnosed, raising their risk of stroke, heart attack and early death, according to the largest ever study of its kind.
Even among those who are diagnosed and receiving medication via their family doctor, in 50% of cases their blood pressure is out of control, the Oxford University study of 1.4 million adults suggests.
Researchers said the findings, published in journal BMJ Public Health, suggested the current approach to detecting and treating high blood pressure in England was “not fit for purpose”.
The study used data from the Our Future Health programme and looked at people enrolled between 2022 and 2025 with high blood pressure, defined as 140/90 mmHg or higher.
Researchers calculated that more than a third of adults (37%) had high blood pressure, with six in 10 of these oblivious to their condition.
Hypertension was almost 50% more common in men than women (42% compared with 29% across all ages), and more common in older people, according to the research.
Despite substantial improvements in high blood pressure detection and control during the 2000s, progress had plateaued since about 2011, the researchers said.
There were also “indications of worsening trends following the Covid-19 pandemic, possibly because disruptions to healthcare delivery may have had lasting effects”.
Wenyu Liu, a medical statistician at Oxford Population Health and lead author of the study, said: “While hypertension is largely a ‘silent killer’, the current approach to detecting and treating high blood pressure is not fit for purpose.
“Our study highlights the prevalence of hypertension across demographics. This underscores the need for population-wide prevention strategies alongside targeted treatment for people at high cardiovascular risk.”
The researchers said “the most striking finding” of the study was the high absolute number and the high proportion of people with undiagnosed hypertension. It also found only half of adults with high blood pressure treated by a GP were adequately controlled.
Dr Iain Turnbull, a GP, deputy chief medical officer at Our Future Health and a clinical research fellow at Oxford Population Health, said it was not clear why 50% of patients who said they were taking blood pressure-lowering drugs had uncontrolled hypertension.
“Blood pressure varies considerably between people, and some people need changes in dose or two or more different medicines before it is brought under control. Other health conditions and medications can affect blood pressure, too.
“There are also practical and social factors: side effects, complicated treatment regimens and competing health or life pressures can make medicines difficult to take consistently. Weight, diet, salt intake, alcohol and physical activity can also influence blood pressure.
“So a high reading can have many explanations and shouldn’t be seen simply as a reflection of what an individual patient or healthcare professional has done.
“There are also some important caveats … we did not have prescribing records available to independently confirm medication use, and a blood pressure measurement on one day does not necessarily represent someone’s usual blood pressure.
“Even with those caveats, I wouldn’t regard 50% as a satisfactory figure. Persistently high blood pressure increases the risk of stroke and heart disease, and bringing it under control reduces that risk.”
Prof Bryan Williams, chief scientific and medical officer at the British Heart Foundation, said the study “paints a concerning picture of the scale of undetected high blood pressure in the UK, and the challenges of keeping blood pressure under control in those already receiving treatment”.
“Better detection and treatment could help tens of thousands of people to avoid a preventable heart attack and stroke,” he added. “But to achieve this, we will need to rethink how we identify, treat and support those at risk so that blood pressure checks and effective treatment can benefit everyone.”
