Angina – the sensation of central chest pain frequently provoked by exertion or cold – is the most common symptom of coronary heart disease (CHD).
Deaths from CHD account for 25% and 20%, respectively, of all male and female fatalities. Almost one in six occur in people below the age of 65 who would otherwise have had many years of life ahead of them.1
CHD is one of the most common single causes of adult death in the UK, and particularly in Scotland where it causes more than 13000 deaths every year.
Patients often mistake angina for indigestion, or shrug it off because it goes away when they rest or warm up. Many patients also ignore it until it becomes quite severe, or do not want to 'trouble' the doctor with a symptom that appears to be transient and therefore of little significance.
Why angina is important
It is essential that both patients and doctors are aware of the importance of angina. They need to recognise that angina is not in itself a diagnosis, but rather a symptom of CHD that requires urgent investigation and treatment.
Continuous morbidity recording (CMR) data have shown that the average GP has only around 45 consultations for every 1000 patients in the practice per year where the main symptom is angina.2 Thus the opportunity for picking up these cases and for providing effective treatment is limited.
If we are to turn these CHD rates around, it is essential that we identify individuals at particular risk, at as early a stage as possible, and manage these risk factors, so that preventive treatment can be given and the risk of suffering a myocardial infarction (MI) can be reduced.
This is even more important for patients who have previously suffered an MI and for whom treatment should be initiated in order to prevent a second MI.
Several baseline surveys and audits of performance have now also reported a considerable gap between normal practice and optimum secondary prevention with regard to aspirin, lipids, blood pressure, smoking, diet, weight and exercise for all patients with CHD.3–8
Putting this simply, we have too few patients on aspirin, too many patients with uncontrolled high blood pressure or high cholesterol, too many patients who smoke and too many patients who are overweight or take no exercise.
Many, but not all, patients will have these risk factors for a heart attack and it is the treatment of these risk factors that will reduce deaths and disability from heart attacks.
Aims of the guideline development group
Against this background the Scottish Intercollegiate Guidelines Network (SIGN) formed a guideline development group to develop a clinical guideline on the management of stable angina9 which would give all clinicians clear guidance on the identification and management of this condition.
A multidisciplinary group covering all of the specialties was formed, and agreement was reached on the key questions to be asked by the group during the process of the guideline's development.
It was the experience of the group that time spent defining these questions, at the beginning of the process, was extremely worthwhile.
A detailed literature search strategy was therefore developed by the SIGN Information Manager, to enable review of the medical literature and existing guidelines published by a wide range of other bodies.
Within this process, the group reviewed the North of England evidence-based guideline for the primary care management of stable angina.10 The group decided that the quality and depth of the systematic review undertaken for the North of England guideline made duplication of this work unnecessary.
The group therefore decided to base the SIGN guideline on the North of England guideline, adapting it to produce one that was suitable for use within Scotland.
Searches for other guidelines or systematic reviews were also carried out, covering key internet sites, EMBASE, Healthstar, Medline and Pascal.
The development of the SIGN guideline followed the standard methodology for SIGN guideline development11 and the evidence base for the recommendations was very strong.
There is enough first-class evidence from randomised controlled trials in patients with CHD and angina to tell us the right things to do.
There is also good evidence that if patients with angina and CHD stopped smoking, had their blood pressure treated, modified their diet, took more exercise, reduced their weight (if overweight), had their cholesterol controlled and took aspirin, we would see a substantial reduction in heart attacks.
This guideline brings together the evidence and the recommendations of what to do for busy doctors, and also for patients so that they can understand what to do for themselves and what to expect from the NHS. The guidance is summarised in the accompanying quick reference guide (see Figure 1, below).
|Figure 1: Quick Reference Guide to the management of stable angina (SIGN Guideline No. 51)|
|© Scottish Intercollegiate Guidelines Network, 2001|
The guideline recommends, in particular, that structured care and follow-up should be provided, and highlights the successful reductions in mortality rates and symptomatology that can be achieved through, for example, the provision of nurse-led secondar prevention clinics.
Clear guidance is also provided on:
- The investigation of patients' symptomatology
- When to refer the patient on for further investigation/cardiological opinion
- Identification and management of risk factors, particularly high cholesterol, smoking and diabetes, along with hypertension, dietary factors, obesity and excess alcohol consumption
- The most effective drug treatments
- Key points for audit (17 points to enable clinical teams to audit and monitor their treatment of angina are identified; see Table 1, below).
Who else might benefit?
It is hoped that the guidance on the management of risk factors will also benefit patients other than those with angina, such as those with hypertension or diabetes. These diseases are silent killers in their own right, with few or no symptoms until they have caused irreversible damage to the body. Searching for these risk factors in patients with angina has additional benefits for those patients when they start effective treatment.
If every patient recognised angina and every doctor treated their patients using this guideline, we could see a 30% or more reduction in the incidence of heart attacks. We would also see a reduction in strokes and other ill-health.
The guideline does, however, need to:
- Be made widely available to members of the public who might experience angina but do not believe that they are ill
- Be read by patients with angina
- Be easily available for doctors to use when seeing patients with angina.
The guideline was issued in April 2001 and will be considered for review in 2003.
The stable angina guideline marks the first of SIGN's new-style guidelines. It is slightly shorter and, it is hoped, easier to use. The accompanying, and popular, Quick Reference Guide (see Figure 1, above) has also been redesigned and is now available in a new pocket-size format.
By listening to their guideline users' comments, and responding to their needs, SIGN is confident that the new format of guideline coupled with their new distribution strategy and electronic publishing programme (CD-ROMs and website) will increase the accessibility of SIGN guidelines.
Making the guideline available is an essential first step, but implementing the recommendations within the guideline is the most important step for both patients and doctors.
- The full guideline Management of Stable Angina: A national clinical guideline (SIGN No. 51) and the Quick Reference Guide are available from SIGN Executive, Royal College of Physicians, 9 Queen Street, Edinburgh EH2 1JQ (tel 0131 225 7324), or can be downloaded free of charge from www.sign.ac.uk
- Register General for Scotland. Annual Report 1999. Edinburgh: General Register Office (Scotland), 2000.
- Scottish Health Statistics, 2000 (cited 20 March 2001). Available from: www.show.scot.nhs.uk/isd/Scottish_Health_Statistics/SHS2000/home.htm
- Bowker TJ, Clayton TC, Ingram J et al. A British Cardiac Society survey of the potential for the secondary prevention of coronary disease: ASPIRE (Action on Secondary Prevention through Intervention to Reduce Events). Heart 1996; 75: 334-42.
- EUROASPIRE. A European Society of Cardiology survey of secondary prevention of coronary disease: principal results. EUROASPIRE Study Group. European Action on Secondary Prevention through Intervention to Reduce Events. Eur Heart J 1997; 18: 1569-82.
- Bradley F, Morgan S, Smith H, Mant D. Preventive care for patients following myocardial infarction. The Wessex Research Network (WReN). Fam Pract 1997; 14: 220-6.
- Dovey S, Hicks N, Lancaster T et al. Secondary prevention after myocardial infarction. How completely are research findings adopted in practice? Eur J Gen Pract 1998; 4: 6-10.
- Campbell NC, Thain J, Deans HG, Ritchie LD, Rawles JM. Secondary prevention in coronary heart disease: baseline survey of provision in general practice. Br Med J 1998; 316: 1430-4.
- Brotons C, Calvo F, Cascant P, Ribera A, Moral I, Permanyer-Miralda G. Is prophylactic treatment after myocardial infarction evidence-based? Fam Pract 1998; 15: 457-61.
- Scottish Intercollegiate Guidelines Network. Management of Stable Angina: A national clinical guideline.Edinburgh: SIGN, April 2001. This can be downloaded free of charge from the SIGN website at www.sign.ac.uk
- Eccles M et al. North of England Evidence Based Guideline Development Group. Evidence based clinical practice guideline. The primary care management of stable angina. Centre for Health Services Research, Newcastle Upon Tyne. Report 98,1999.
- SIGN 50: A Guideline Developer's Handbook. Scottish Intercollegiate Guidelines Network, 2001.