Up to one-quarter of the six million people being treated for high blood pressure in the UK may have been misdiagnosed.
The standard method of measuring blood pressure is inaccurate and should be replaced by 24-hour monitoring, using a device worn on the waist, experts advise. The recommendation, by a panel of the National Institute for Clinical Excellence (Nice), is expected to be adopted around the world – the first change to the way blood pressure is measured for more than a century.
High blood pressure affects an estimated 12 million people in the UK, one in four of the adult population and one in two of those over 60. But it remains undiagnosed in more than half of them. It is one of the most important causes of heart disease, stroke and kidney disease and controlling it is one of the most effective ways of preventing premature death.
Traditionally, blood pressure is taken by a cuff attached to the patient's upper arm and pumped up to block the blood flow before being released slowly to measure the pressure at which blood starts to flow again.
Many patients suffer from "white coat syndrome" – their blood pressure rises because of anxiety triggered by a visit to the surgery. A more accurate measure can be obtained by monitoring blood pressure for 24 hours using a device attached to the waist that pumps up the cuff worn around the arm every half hour and takes a reading, all of which are then averaged out.
Fewer than one in 10 patients are diagnosed in this way. The devices cost more than £1,000 and drugs prescribed for blood pressure on the NHS cost £1bn a year. Nice estimates that introducing the devices would save £10bn annually after five years.
Bryan Williams, Professor of medicine at the University of Leicester, who led the Nice panel, said: "The important recommendations in this guideline will affect the treatment of millions of people in our country. It is a step change that is likely to be replicated across the world."
The research is published in The Lancet.Reuse content