A 10-step approach to successful hypertension management in practice

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Each year since 1997, our practice has produced a detailed annual quality report. This has focused on our achievements, as well as shortcomings, and established a set of goals for the coming year.

Long before the nGMS contract and its quality and outcomes framework (QOF), we had identified hypertension as our most prevalent chronic condition. We had also carried out several audits on management.

The first year of the QOF provided the impetus for a more thorough study¹ and we developed a 10-step approach to hypertension management. This practice protocol can be summarised on a single side of A4 paper (Figure 1, below).

Figure 1: The ten steps for hypertension management

We based our initiative on the British Hypertension Society’s guidelines for management of hypertension and the NICE guideline on management of hypertension in adults in primary care.^2-4 More recently, we have incorporated evidence from the Anglo- Scandinavian Outcomes Trial (ASCOT).⁵

The first year of the QOF

Our practice was one of only 222 of the 8576 practices in England to achieve the maximum of 1050 points in the QOF during its first year.We easily met the five indicators for hypertension without recourse to exception reporting (Table 1, below).

Table 1: Hypertension quality indicators and points
Indicator	Audit structure: register	Target	Practice	%	Points
BP 1	Register of patients with hypertension	Register	738	100%	9
	Audit process: results recorded
BP 2 BP 3 BP 4	Smoking status recorded Smokers given cessation advice at least once Quality BP check in past 9 months	90% 90% 90%	738 109 692	100% 100% 94%	10 10 20
	Audit outcomes: blood pressure control
BP 5	Quality =<150>	70%	609	83%	56
Total points available					105
Patients with BP <140/85 mmHg in past 9 months			433	59%

The hypertension indicators illustrate the three principles of clinical audit – structure, process and outcome. It is important to remember that the QOF outcome target of =<150>2 Some 83% of our patients with hypertension reached the QOF audit target, while only 59% achieved the lower clinical target.

The 10-step approach

Our study enabled us to make significant improvements, particularly in the areas of blood pressure measurement, practice screening, prescribing and follow up (steps 2, 3, 8 and 9).

Step two: reliability of BP measurement

With 56 points, Indicator 5, for blood pressure outcome (BP 150/90 mmHg or below, measured in the past 9 months), justifiably carries the highest score of the 76 clinical QOF targets.

QMAS extracts computer data, which relies for accuracy on practice staff entering the correct data into the system.The QOF sets no quality standards for sphygmomanometry, and error can be introduced through faulty equipment, poor technique or observer bias.

During our study we used large-dial, wall-mounted, calibrated Speidel and Keller Maxi-Stabil 3 sphygmomanometers. This is one of the few aneroid sphygmomanometers to have been validated for accuracy.⁶ We checked results for observer bias (Box 1, below) and demonstrated a terminal zero preference of 6.6 for systolic measurements.This is lower than that found in many GP surveys, but is still unsatisfactory.

Box 1: How to investigate systolic BP readings for bias

Create an Excel spreadsheet of QOF data for patients who are on the hypertension register (preferably at the end of the QOF year) Select data/filters/auto filter Click on the auto filter arrow at the top of the column for systolic readings and select 150.This will display the number of BP readings at the threshold for Indicator 5 out of the total on the register Repeat the exercise for all systolic readings ending with a zero (e.g. 120, 130, 140, etc) Compare these numbers with those that do not end in a zero, to reveal any bias

We have now purchased Omron M7 automated oscillometric sphygmomanometers, which will eliminate bias.

Step three: screening for hypertension

Opportunistic screening for hypertension and other cardiovascular risk factors in primary care should be easy, because 70% of patients consult their GP every year and 90% consult within 5 years.

Patients never refuse a blood pressure check, unlike cervical smears and mammography, and in 5 years GPs will spend only one or two minutes per patient on screening. For an average GP list of 1800 patients, this creates a workload of around 9 hours each year or 11 minutes per week. No other screening programme can rival this for efficiency.

In our practice, paperless records and on-screen prompts made opportunistic recording a simple task. Table 2 (below) gives the percentages of patients whose risk factors were recorded in the 5 years to 1 April 2005. This shows that each partner comfortably achieved a screening uptake of more than 90% for blood pressure and smoking status, while the average for the practice was 94%. The template used to capture this information takes approximately 5 minutes to complete on 1 April each year.

Table 2: Risk factors recorded during 5 years to 1 April 2005
Records of:	GP1	%	GP2	%	GP3	%	Total	%
Patients aged 25 - 79 years Blood pressure Smoking status Alcohol units Body mass index Family history of CHD or CVD	1348 1292 1295 1291 1273 1230	96 96 96 94 91	1318 1234 1232 1094 1079 851	94 93 83 82 65	1567 1435 1471 1342 1311 1175	92 94 86 84 75	4233 3961 3998 3727 3663 3256	94 94 88 87 77

Step eight: appropriate prescribing

In September 2004 we made a detailed study of the prescribing of anti-hypertensive drugs in the practice. Diuretics were the most popular choice, with 55% of our hypertension patients taking this class of drug, while 50% of hypertension patients were taking an ACE inhibitor or an angiotensin receptor blocker, 38% were taking a calcium channel blocker and 38% a beta blocker.

The average number of drugs that each partner prescribed per patient varied, from 1.67 to 1.98 (Table 3, below). Not surprisingly, we found better blood pressure control in patients taking three agents than in those taking one. Some 79% of patients taking three agents were controlled to the target of =<150>

Table 3: ABCD drugs prescribed
	GP1	%	GP2	%	GP3	%	Total	%	BP =<150/90 mmHg
Patients prescribed ABCD drugs Step 1: One ABCD agent Step 2:Two ABCD agents Step 3:Three ABCD agents Step 4: Four ABCD agents Five ABCD: both ACE & ARB Total ABCD drugs prescribed ABCD drugs per patient	212 75 80 45 10 2 420 1.98	35 38 21 5 1	215 101 85 27 2 0 360 1.67	47 40 13 1 0	219 89 83 37 10 0 406 1.85	41 38 17 5 0	646 265 248 109 22 2 1186 1.84	41 38 17 3 0	69% 76% 79% 68%

We also examined our prescribing to see whether it corresponded with the guidelines’ recommendations.We found that it showed better correlation with the BHS guidelines’ ABCD rule⁷ than with the NICE guideline at the first, second and third steps of treatment (Table 4, below).

Table 4: How prescribing conformed with guidelines’ recommendations
Patients on one drug (Step 1)	265
Follows BHS IV age and ethnicity guidelines: A or B <55 years, non-black; C or D=>55 years or black	148	56%
Follows NICE guideline: D first but B may be used in patients <55 years	86	32%
Patients on two drugs (Step 2)	248
Follows BHS IV guidelines: two drugs in different groups (A or B + C or D)	179	72%
Follows NICE guideline for known diabetics and patients at raised risk of new-onset diabetes - family history diabetes, BMI =>30, impaired glucose tolerance, South Asian or African- Caribbean origin: D + A; For all other patients: D + B	65	26%
Patients on three drugs (Step 3)	109
Follows BHS IV guidelines:A or B + C + D	57	52%
Follows NICE guideline for known diabetics and patients at raised risk of new-onset diabetes: D + A + C; All others: D + B + C	35	32%
A, ACE inhibitor or angiotensin receptor blocker; B, beta-blocker; C, calcium channel blocker; D, low-dose thiazide-type diuretic

Of course, there are flaws in this analysis – most practice prescribing predates the publication of the BHS guidelines and the NICE guideline, both of which were published in 2004. Also, we made no allowance for the effect of co-morbidity on treatment selection except for diabetes in the NICE analysis. Nevertheless, this prescribing audit proved to be a worthwhile educational venture by encouraging partners to study the guidelines more thoroughly.

Step 9: follow up

The ASCOT study published in the Lancet in September 2005 found significant reductions in cardiovascular mortality and stroke in hypertension patients treated with a calcium-channel blocker and an ACE inhibitor, compared with a combination of low-dose thiazide-type diuretic and beta-blocker. As a result, national guidelines on the management of hypertension are under revision.

However, even when recommendations on hypertension management change, it will remain important for GPs to focus on selecting the most appropriate therapy for the individual patient. We have introduced a simple method to encourage this by incorporating the reason for prescribing and the drug class letter, taken from the BHS guidelines’ ABCD rule, into our instructions on repeat prescribing. Some prescribing examples for anti-hypertensives and drugs for co-morbidity are given in Box 2 (below).

Box 2: Example of instructions on repeat prescribing
Perindopril 8 mg Losartan 50mg Atenolol 50 mg Amlodipine 10 mg Bendroflumethiazide 2.5 mg Simvastatin 40 mg	1 tablet each morning for BP (A1) 1 tablet each morning for BP (A2) 1 tablet each morning for BP (B) 1 tablet each morning for BP (C) 1 tablet each morning for BP (D) 1 tablet at bedtime for cholesterol

This system helps to eliminate inappropriate prescribing. For example, although 79% of our hypertension patients taking three drugs were controlled to target, only 52% were taking the correct combination of drugs as recommended by the BHS guidelines’ ABCD rule. A critical review of therapy in the remaining 48% could improve their blood pressure control.

One further refinement that we have made to facilitate logical prescribing is to make a careful record of adverse effects and intolerance to agents that have been tried and withdrawn.

Conclusion

Nearly all routine hypertension management is carried out within primary care, and the QOF has successfully enabled GPs to improve the health of their hypertensive patients.

Having begun with small audits, our practice has now carried out a very detailed dissection of all aspects of hypertensive care.

We intend our 10-step approach to be a dynamic document that can be updated and improved, and Bury PCT is keen to roll out our initiative in other practices.

References

1. Standing P, Deakin H, Norman P, Standing R. Hypertension – its detection, prevalence, control and treatment in a quality driven British general practice. Br J Cardiol 2005; 12: 471-6.
2. Williams B, Poulter NR, Brown MJ 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: 139-85.
3. Williams B, Poulter N, Brown MJ et al. British Hypertension Society guidelines for Hypertension Mnagement 2004 (BHS-IV): Summary. Br Med J 2004; 328: 634-40.
4. National Institute for Clinical Excellence. Hypertension – management of hypertension in adults in primary care. NICE Clinical Guideline 18. London: NICE, 2004.
5. Dahlof B, Sever PS, Poulter NR 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: 895-906.
6. Reinders A, Jones CR, Cuckson AC, Shennan AH. The Maxi Stabil 3: validation of an aneroid device according to a modified British Hypertension Society protocol. Blood Pressure Monitor 2003; 8 (2): 83-9.
7. Brown M, Cruickshank JK, Dominiczak AF et al. Better blood pressure control; how to combine drugs. J Hum Hypertens 2003; 17: 81-6.

Guidelines in Practice, December 2005, Volume 8(12) © 2005 MGP Ltd further information | subscribe