Dr Mark Davis discusses the changes to the treatment algorithm in the updated NICE/BHS hypertension guideline

For the past 2 years, my practice has been treating patients with hypertension by following the most recent British Hypertension Society guidelines (BHS IV).1

These have been easily understood by the practice team and, being pragmatic, have been readily incorporated into the practice protocol.

The need for an update

BHS IV, despite having many similarities with the 2004 NICE guidance,2 did have important differences in the drug treatment algorithm. Additionally, new trial evidence has cast a shadow over the use of beta-blockers in uncomplicated hypertension.3

NICE noted the concern over beta-blockers and recognised that if two highly regarded guidelines conflicted, confusion might ensue. Therefore, NICE decided to instigate a rapid update of its guideline on hypertension in adults in primary care.4

This was prompted by the availability of new information from recent large outcome trials, such as ASCOT.3 Importantly, the BHS agreed to adopt this review as an update on the pharmacological treatment of hypertension for its own BHS IV guideline.1

New treatment algorithm

Based on the available evidence it was decided that:

  • most people will require more than one drug to achieve their blood pressure target
  • in the absence of compelling indications, beta-blockers should not be the preferred initial treatment for hypertension; this view was further supported by the finding that there was an increased risk of developing diabetes in patients treated with a beta-blocker, particularly in combination with a diuretic
  • calcium channel blockers (CCBs) and thiazide-type diuretics are the drugs most likely to confer benefit as firstline treatments for the majority of patients
  • in younger patients (pragmatically defined as less than 55 years), angiotensin-converting enzyme (ACE) inhibitors might result in greater blood pressure lowering than CCBs or thiazide-type diuretics
  • people of Afro-Caribbean descent usually respond less well to beta-blockers or ACE inhibitors; thus for this group, CCBs or thiazide-type diuretics should be the firstline treatment, regardless of age
  • for reasons of cost, it is suggested that an angiotensin receptor blocker (ARB) should only be used instead of an ACE inhibitor when the latter is not tolerated.

For the second step of treatment, the addition of an ACE inhibitor to a CCB or diuretic (or a CCB or diuretic to an ACE inhibitor in the younger group) is recommended (Figure 1). There is less evidence to support the third treatment step, but the guideline development group concluded that the combination of an ACE inhibitor, a CCB and a thiazide-type diuretic would be a reasonable combination.

Figure 1: Treatment algorithm for patients with newly diagnosed hypertension

Reproduced by kind permission of the National Institute for Health and Care Excellence

Should patients stay on beta-blockers?

Many of our patients who do not have compelling indications will be taking beta-blockers for their hypertension. What should we do when our patients visit us at the surgery clutching a press cutting warning of the harm that will befall them should they continue with their current treatment?

The most important thing is still to reduce the patient's blood pressure to the therapeutic target. Blood pressure lowering is more important than what agent we use to do it. However, NICE sensibly suggests that if blood pressure is not controlled, treatment should be revised according to the new guidance. If the patient's blood pressure is well controlled then long-term management should be considered as part of their routine review.

There is no absolute need to replace the beta-blocker with an alternative agent as the risks associated with loss of blood pressure control may outweigh any advantage gained by a change in treatment. If appropriate, the beta-blocker should be withdrawn gradually.

Conclusion

NICE has been subject to criticism from primary care, which suspected that it was a 'cost-cutting agency'. This is not true and the production of this guideline does illustrate the ability of NICE to respond quickly to the changing evidence base. By collaborating with the BHS, primary care has been provided with a coherent and consistent approach to the pharmacological management of hypertension.

Guidelines in Practice, July 2006, Volume 9(7)
© 2006 MGP Ltd
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  1. Williams B, Poulter N, Brown M et al. Guidelines for management of hypertension: report of the fourth working party of the British Hypertension Society, 2004; BHS IV. J Hum Hypertens 2004; 18 (3): 139-85.
  2. National Institute for Clinical Excellence. Hypertension – management of hypertension in adults in primary care. NICE Clinical Guideline 18. London: NICE, 2004.
  3. Dahlöf B, Sever P, Poulter N et al. ASCOT Investigators. Prevention of cardiovascular events with an antihypertensive regimen of amlodipine adding perindopril as required versus atenolol adding bendroflumethiazide as required, in the Anglo-Scandinavian Cardiac Outcomes Trial-Blood Pressure Lowering Arm (ASCOT-BPLA): a multicentre randomised controlled trial. Lancet 2005; 366 (9489): 895-906.
  4. National Institute for Health and Care Excellence. Hypertension: Management of hypertension in adults in primary care (partial update). NICE Clinical Guideline 34. London: NICE, 2006.