Cardiovascular experts have completely redrawn the guidance on the diagnosis and treatment of hypertension with the launch of a ‘radical and bold’ new NICE guideline today.
The treatment algorithm has been updated to ‘give GPs a much stronger steer’ towards the use of calcium channel blockers as the preferred first-line treatment in patients aged over 55 years, or black patients of any age.
For patients aged under 55, ACE inhibitors and angiotensin receptor blockers remain first-line drugs, and CCBs should be added as a second-step drug.
If blood pressure remains uncontrolled, GPs should use thiazide-like diuretics. But in a major change, the guideline development group recommended that when starting treatment with a diuretic, the evidence of cost and clinical efficacy favoured the thiazide-like diuretic chlortalidone 12.5mg or 25mg once daily, or indapamide 1.5mg modified release or 2.5mg daily, in preference to conventional thiazide diuretics such as bendroflumethiazide or hydrochlorothiazide.
The group also incorporated evidence from the UK-based HYVET study of nearly 4,000 hypertensive patients over 80 years, which found standard hypertensive treatment reduced the risk of fatal stroke drop by nearly 40%, heart failure by 64% and all-cause mortality by over a fifth.
As a result, the guidance recommends GPs ‘offer people aged 80 years and over the same antihypertensive drug treatment as people aged 55-80 years, taking into account any comorbidities’ – though GPs should only treat elderly patients if their systoilic blood pressure of 160mm Hg or above, and the treatment target is lower, at 150/90mm Hg compared with 140/90mm Hg in other patients.
But as reported by Pulse in February, the key change for GPs will be the use of ambulatory blood pressure monitoring to confirm a diagnosis in a patient with a clinical reading of 140/90 mm Hg.
The guideline development group estimated that the use of ABPM will drastically reduce white coat hypertension, which they estimated could mean that 25% of the 12 million patients on UK practice hypertension registers are misdiagnosed.
In a modelling study also published today in The Lancet, the guideline development group estimated the switch to ABPM is more cost-effective than both clinical readings and home monitoring, for all age groups and in men and women.
A costing report by NICE also estimated the change in diagnostic method would cost the NHS £5.1m a year. But with reduced drug costs assuming fewer people are initiated on treatment there would be a net saving of £10m after five years.
Professor Richard McManus, professor of primary care cardiovascular research at the University of Birmingham and a GP in the city, concluded: ‘Ambulatory monitoring as a diagnostic strategy for hypertension after an initial raised reading in the clinic would reduce misdiagnosis and save costs.’
‘Additional costs from ambulatory monitoring are counterbalanced by cost savings from better targeted treatment. Ambulatory monitoring is recommended for most patients before the start of antihypertensive drugs.’
He told Pulse: ‘This is an ideal way in which people can group together and work in consortia to share devices.’
Professor Bryan Williams, professor of medicine at the University of Leicester and chair of the guideline development group, told Pulse: ‘We’re under no illusions that this is going to be a major implementation challenge but we are convinced that the long term benefits for patients will be significant. People with hypertensions are potentially treated for 50 years or more and we have to get it right.’
‘We expect this change to be implemented over the next year or so to allow time for commissioners to design their services, this might prompt questions about how blood pressure is managed in the community and that will be a good thing.’