Dr John Cannon and his team, runners up in the Guidelines in Practice Cardiovascular Disease Award 2007, exceeded target levels for hypertension by switching patient therapy


Dr John Cannon and his team from the Ixworth Surgery, Bury St Edmunds, were joint runners up in the Guidelines in Practice Cardiovascular Disease (CVD) Award 2007. They set up a project to review the pharmacotherapy of their patients with hypertension in line with current British Hypertension Society (BHS) and NICE guidance.1

Suboptimally controlled hypertension is a major risk factor for the development or exacerbation of coronary heart disease (CHD)/heart failure, chronic kidney disease, retinopathy, and diabetes, and the project team felt that its patients would benefit most by rigorous implementation of these guidelines.

Project criteria

Research suggests that implementation of evidence-based pharmacotherapy is poor2 and that beta blockers are still used inappropriately in the early management of hypertension.3 The team from Ixworth Surgery aimed to identify patients on a beta blocker/thiazide combination, prioritising those who were suboptimally controlled (systolic blood pressure >150 mmHg and/or diastolic blood pressure >90 mmHg) and who had no clinical indication for a beta blocker.

Trials have shown that the majority of patients require a combination of two or more drugs to reduce blood pressure to target levels.4–6 The aim of the project was to transfer appropriate patients from the beta blocker/thiazide combination to angiotensin-converting enzyme (ACE) inhibitor with additional diuretic or calcium-channel blocker (CCB), following the ACD algorithm in the updated NICE guideline (see Figure 1).1

Figure 1: ACD algorithm for the sequencing of drugs in newly diagnosed hypertensive patients

Figure 1: ACD algorithm for the sequencing of drugs in newly diagnosed hypertensive patients

National Institute for Health and Care Excellence (NICE) (2006) CG 34 Hypertension: management of hypertension in adults in primary care. London: NICE. Reproduced with permission. Available from www.nice.org.uk.

Selection and briefing of patients

The team searched the practice patient database to identify a patient sample from its hypertension register. Fifty-one patients who met the qualifying criteria were then invited by letter to attend for a routine consultation. Dispatch of the letters was staggered over an 8-week period so that only six or seven extra appointments were needed weekly to avoid placing too great a demand on available resources.

It was explained to attendees that the new management strategy for their hypertension would help them to achieve the aimed for level of blood pressure. The importance of the lower blood pressure targets and what the health gains would be were also discussed with patients.

Some patients who were already aware of the media debate were forewarned, and were positively enthusiastic. Others were happy with their current regimen and were resistant to change but were prepared to try the new therapy with our support.

Risk assessment

Colleagues at the practice including partners, the Cardiovascular Specialist Nurse, and the Computer Services Lead, encouraged the project and also helped with patients’ concerns where they arose. During the consultations, other risk factors for CVD, as detailed in the JBS 2 guidance,7 were also assessed. These include:7

  • ethnicity
  • smoking history
  • family history of CVD
  • measurement of: BMI; waist circumference; blood pressure; total cholesterol; and high density lipoprotein cholesterol.

All tests were done by appointment so patients were able to fast easily and this avoided the need for repeated testing. Patients fasted if required.

Medication

Medication was reviewed, with all patients being switched to the new drug regimen of ACE inhibitor plus a diuretic or CCB. Angiotensin-receptor blockers (ARB) were used if ACE inhibitors were not well tolerated. As recommended by the NICE guideline, gradual withdrawal of beta blockers was undertaken.

We were aware that some patients could be harbouring covert CHD or heart failure, which had previously been controlled by the beta blockers. This was explained to patients in preparation for cross-tapering of the beta blocker element with the ACE inhibitor and they were advised of the need to contact the surgery in case of adverse symptoms such as angina, shortness of breath, intolerable ankle swelling, or troublesome palpitations.

The thiazide component was either continued or changed to a CCB, according to co-morbidities, reflecting current NICE/BHS guidance.1 Patients were told to contact the surgery if they experienced any similar adverse symptoms. Possible benefits that might also be experienced were described, such as reduced fatigue, decreased impotence, and warmer peripheries.

Other evidence-based interventions were also implemented at these interviews such as prescribing aspirin (where blood pressure was controlled to <150/90 mmHg) and statins as described in JBS 2.7

Where possible we employed fixed-drug combinations in accordance with NICE/BHS1 because concordance is improved by 17–25% using a single tablet compared with taking two or more medications. Research has shown a 30% better blood pressure control with high concordance than low, which translates into better attainment of target blood pressure using fixed-dose combinations.8 Reduced concordance also impairs significant synergistic effects.9

Patient review

Patients were encouraged to phone with any concerns during this transition period. Renal function tests were performed 1–2 weeks after commencing treatment with ACE inhibitors or ARBs, and patients were examined again after 6–8 weeks.

Fasting blood sugar, lipid levels, and baseline liver function tests, if warranted, were also assessed. If the blood pressure had not come down to the target level of ?140/85 mmHg for those with uncomplicated hypertension, or ?130/80 mmHg for those with diabetes or target organ damage, Step 3 of the NICE ACD algorithm was put in place (see Figure 1).1

Blood pressure was rechecked at 6–8 weeks, and if patients were controlled to target, a review was arranged for them after a further 6 months. Those patients who had needed to move to Step 3 of the ACD algorithm1 were reviewed after a further 6–8 weeks with a plan to invoke Step 4 if they were still not hitting target levels for blood pressure.

Results

The practice exceeded the 70% quality and outcomes framework (QOF) parameter for achieving good control of blood pressure (?150/90 mmHg) in patients with CHD, stroke, and hypertension: full points were achieved with 93.5%, 88.7%, and 78.2% of patients being recorded, respectively. The practice also exceeded the 55% QOF parameter in its patients with diabetes by reducing blood pressure to ?145/85 mmHg in 79.1% of that group.

Future of the project

Ixworth Surgery plans to expand the project to identify all those hypertensive patients with a latest blood pressure recording (during the previous 12 months) greater than 150/90 mmHg and offer them an appointment to review blood pressure and cardiovascular risk factors. Again we would aim for a target of ?140/85 mmHg for uncomplicated hypertension and ?130/80 mmHg for patients with target organ damage (and arguably lower for specific disease areas such as chronic kidney disease).

Dr Cannon has lectured locally and regionally on the best practice of hypertension, sharing the success of this project with other general practices in Suffolk.

Summary

The ACD algorithm1 is clear and logical, and it was incorporated easily into normal working practices at the Ixworth Surgery, where our Cardiovascular Specialist Nurse is competent in implementing these guidelines in our CHD clinic. Practice nurses are well placed to implement algorithms, and this is an area that could be easily delegated to them after they have completed the appropriate training.

 

  1. National Institute for Health and Care Excellence. Hypertension: management of hypertension in adults in primary care (partial update). Clinical Guideline 34. London: NICE, 2006.
  2. Whitworth J; World Health Organization, International Society of Hypertension Writing Group. 2003 World Health Organization (WHO)/International Society of Hypertension (ISH) statement on management of hypertension. J Hypertens 2003; 21 (11): 1983–1992.
  3. Carlberg B, Samuelsson O, Lindholm L. Atenolol in hypertension: is it a wise choice? Lancet 2004; 364 (9446): 1684–1689.
  4. Dahlöf B, Sever P, Poulter N; ASCOT Investigators et al. 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.
  5. ALLHAT Officers and Coordinators for the ALLHAT Collaborative Research Group. The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial. Major outcomes in high-risk hypertensive patients randomized to angiotensin-converting enzyme inhibitor or calcium channel blocker vs diuretic: The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). JAMA 2002; 288 (23): 2981–2997.
  6. Hansson L, Zanchetti A, Carruthers S et al. Effects of intensive blood-pressure lowering and low-dose aspirin in patients with hypertension: principal results of the Hypertension Optimal Treatment (HOT) randomised trial. HOT Study Group. Lancet 1998; 351 (9118):1755–1762.
  7. JBS 2: Joint British Societies’ guidelines on prevention of cardiovascular disease in clinical practice. Heart 2005; 91 (suppl 5): v1–52.
  8. Mahmud A, Feely J. Low-dose quadruple antihypertensive combination: more efficacious than individual agents—a preliminary report. Hypertension 2007; 49 (2): 272–275.
  9. Jamerson KA for the ACCOMPLISH investigators. Exceptional early blood pressure control rates: the ACCOMPLISH trial. American Society of Hypertension 2007 Scientific Sessions; May 21, 2007; Chicago, IL.G