Calls for 24-hour blood pressure monitoring, in radical update to NICE guidelines
Patients suspected of having hypertension should be sent home and told to wear a monitor for 24 hours, rather than having their blood pressure checked in the clinic, says NICE.
Currently, anyone suspected of having high blood pressure is diagnosed by a GP with an inflatable arm cuff. They are then invited back to the surgery for additional readings so that an average measurement can be calculated.
But in a radical change to the existing guidelines, NICE now recommends that a diagnosis of hypertension should be made using 24-hour ambulatory blood pressure monitoring (ABPM). This should be offered to patients if the clinic blood pressure is 140/90 mmHg or higher.
The process involves wearing a type of mobile blood pressure monitor that straps around the waist and records numerous blood pressure measurements throughout the day and night.
Today's recommendations are based on substantial new evidence, including a paper published in the Lancet, which suggest that ABPM is a more accurate and cost effective way of diagnosing hypertension than both clinic and home monitoring.
The move towards the use of ABPM will help to avoid the white coat effect - where a patient experiences a temporary increase in blood pressure while having their blood pressure measured by their doctor.
It is thought that up to a quarter of patients experience white coat effect. This can potentially suggest that a patient has high blood pressure when it would be within a healthy range during everyday life.
Bryan Williams, Professor of Medicine at the University of Leicester and Chair of the Guideline Development Group, said: “The important recommendations in this guideline will affect the treatment of millions of people in our country and change the way blood pressure is diagnosed for the first time in more than a century.
“Blood pressure is highly variable so we never use a single reading. Patients are asked to come in and see their GP on at least 2 further occasions. But with AMBP, BP is monitoring throughout the day and then an average value is taken.
“This is done way from the doctor's office, so it is a more natural environment and the results are available after a single day.”
Professor Williams stressed that AMBP should be used for making new diagnoses of hypertension and that patients already diagnosed with hypertension do not need to come forward for re-testing as they will be assessed during their annual review.
Professor Williams added that the introduction of ABPM would be very cost effective, helping to save the NHS £10million after 5 years, by reducing the number of unnecessary consultations and ensuring that only the patients who require treatment receive it.
Professor Mark Caulfield, President of the British Hypertension Society and a member of the Guideline Development Group, added: “The cost of treating people with hypertension is now cheaper than doing nothing. If left untreated, hypertension will go on to be a greater cost to the NHS through strokes and heart attacks.”
Professor Richard McManus, Professor of Primary Care Cardiovascular Research at the University of Birmingham, who is also a GP and was involved in the development of the guidelines, agreed that cost savings could be made but warned that currently not all practices had the right equipment in place.
“The biggest challenge for GPs will be around purchasing the ABPM equipment. Smaller practices may well need to share equipment. But with practices banding together into consortia, this may be the ideal way for practices to share equipment,” he said.
Professor McManus discusses the use of ABPM
Elsewhere, the updated guidelines recommend for the first time that patients over the age of 80 are treated for hypertension.
The use of calcium-channel blockers rather than diuretics is now recommended for patients over 55 or patients of African or Caribbean family origin of any age, following the emergence of new evidence.
NICE has produced a range of support tools to help put this guidance into practice, including slide sets highlighting key messages for local discussion, costing tools on the implementation of ABPM, and a podcaston ABPM with Professor Williams.
24 August 2011