Healthcare guidance body NICE has today (8 August) published a clinical guideline on the diagnosis and management of lower limb peripheral arterial disease. The guideline makes a number of important recommendations that aim to resolve the considerable uncertainty and variations in practice that currently exist in this area and improve outcomes for patients.

Peripheral arterial disease is a common condition, affecting 3% to 7% of people in the general population and 20% of people over the age of 60, in which the arteries carrying blood to the legs and feet become narrowed or blocked. The main cause is atherosclerosis, which is the build up of fatty deposits on the arterial walls. Pain on walking which stops after resting (intermittent claudication) is the most common initial symptom of peripheral arterial disease and is the result of the narrowed arteries not delivering adequate blood to leg muscles. As well as having a detrimental impact on quality of life, intermittent claudication also indicates that there is an increased risk of heart attack and stroke compared with patients with peripheral arterial disease who do not have the symptom. Even when asymptomatic, peripheral arterial disease is a marker for an increased risk of potentially preventable cardiovascular events.

In its more severe manifestations, peripheral arterial disease may lead to a condition called critical limb ischaemia which in turn can progress to severe intractable pain, ulceration and gangrene. Those with critical limb ischaemia are at significant risk of developing irreversible ischaemic damage to the leg or foot if they do not receive appropriate treatment and this may lead to the need for amputation. Overall approximately 1% to 2% of people with intermittent claudication will eventually undergo amputation, making peripheral arterial disease the largest single cause of lower limb amputation in the UK.

Treatments for peripheral arterial disease are aimed at relieving the symptoms, and depend on the level of severity of the condition. They range from changes in life style (for example, smoking cessation), advice to exercise, management of cardiovascular risk factors (for example through taking aspirin and statins) and vasoactive drug treatment such as naftidrofuryl, to endovascular treatments (including balloon angioplasty, endovascular stents and a range of new adjunct or alternative treatments and techniques) and surgical reconstruction to unblock or bypass occluded or narrowed arteries.

Key priorities for implementation identified in the guideline include:

• Offer all people with peripheral arterial disease information, advice, support and treatment regarding the secondary prevention of cardiovascular disease, in line with published NICE guidance on:

- smoking cessation

- diet, weight management and exercise

- lipid modification and statin therapy

- the prevention, diagnosis and management of diabetes

- the prevention, diagnosis and management of high blood pressure

- antiplatelet therapy.

· Assess people with suspected peripheral arterial disease by:

- asking about the presence and severity of possible symptoms of intermittent claudication and critical limb ischaemia

- examining the legs and feet for evidence of critical limb ischaemia, for example ulceration

- examining the femoral, popliteal and foot pulses

- measuring the ankle brachial pressure indexⁱ

• Offer contrast-enhanced magnetic resonance angiography for people with peripheral arterial disease who need further imaging (after duplex ultrasound) before considering revascularisation.
• Offer a supervised exercise programme to all people with intermittent claudication.
• Ensure that all people with critical limb ischaemia are assessed by a vascular multi-disciplinary team before treatment decisions are made.
• Do not offer major amputation to people with critical limb ischaemia unless all options for revascularisation have been considered by a vascular multi-disciplinary team.

Professor Mark Baker, Director of the Centre for Clinical Practice at NICE said: “Lower limb peripheral arterial disease is not only potentially life-threatening, but the severe pain that can be associated with the disease can have a large impact on the quality of life of people with the condition because of the effects of restricted mobility on independence, social life, recreation and work. However, despite improvements in diagnostic methods, together with the emergence of new treatments and organisational changes in the provision of vascular services, it is clear that there is considerable uncertainty and variation in practice across England and Wales, resulting in less than optimal outcomes for some patients with suspected or confirmed peripheral arterial disease. This guideline aims to resolve that uncertainty and variation by highlighting clear diagnostic and treatment pathways and in doing so improve outcomes for patients.”

Jonathan Michaels, Professor of Clinical Decision Science, University of Sheffield, and Chair of the Guideline Development Group, said: “Poor circulation to the legs is a common problem usually caused by narrowing of one or more of the arteries that supply the legs. This peripheral arterial disease can lead to disabling symptoms and may indicate more widespread cardiovascular disease that puts people at risk of stroke and heart disease. This guideline provides clear recommendations on reducing the risk of future circulatory problems, and on accurate diagnosis and treatment of the disease in the legs. The importance of lifestyle changes is emphasised, particularly the benefit of exercise and supervised exercise programmes. For those requiring further treatments for their leg symptoms the recommendations cover modern diagnostic methods, surgery and less invasive treatments, which should be available from multi-disciplinary teams able to offer a full range of specialist treatments.”

Duncan Ettles, Consultant Vascular Interventional Radiologist, Hull Royal Infirmary and member of the Guideline Development Group, said: “Peripheral arterial disease has a relatively high incidence within the UK but is clear that recognition and treatment of the problem shows significant regional variation. The guideline provides clear advice on the initial assessment and management of people with peripheral arterial disease in primary care and important recommendations for better provision of supervised exercise programmes for patients with intermittent claudication. The guideline also adds weight to the case for better availability of non-invasive imaging, particularly magnetic resonance angiography, in patients being investigated for peripheral arterial disease. In patients with critical limb ischaemia the guideline supports early referral to secondary care to avoid the potential for failed revascularisation and amputation.”

Anita Sharma, GP Principal, Clinical Director Vascular and Elective Care Clinical Commissioning Group, Oldham and member of the Guideline Development Group, said: “Patients with peripheral arterial disease are under diagnosed and undertreated despite the fact that it is associated with an increased risk of cardiovascular mortality. Patients with asymptomatic peripheral arterial disease are just as likely to progress to critical ischaemia as those with symptoms. An early diagnosis by doing ankle brachial pressure index measurement, introducing risk reduction strategies and maximising secondary prevention can slow down the progression of the condition and this can be easily done in primary care. For me as a GP peripheral arterial disease management means Prevent an Amputation and Death due to cardiovascular event.”

Peter Maufe, patient representative on the guideline development group, said: “For many patients with peripheral arterial disease, modifiable risk factors such as smoking, poor diet and lack of exercise have probably played a significant part in the development of their condition. One of the key recommendations in the guideline therefore is to offer all people with peripheral arterial disease appropriate information, advice, support and treatment in line with current NICE guidance on a number of important modifiable risk factors including smoking cessation, diet, weight management and exercise. Importantly, the guideline also recommends that all patients with intermittent claudication are offered a supervised exercise programme.”

Ends

Notes to Editors

References

i. The ratio of the blood pressure in the lower legs to the blood pressure in the arms. Compared to the arm, lower blood pressure in the leg is an indication of peripheral arterial disease. The ABI is calculated by dividing the systolic blood pressure at the ankle by the systolic blood pressures in the arm.

About the guideline

1. The NICE guideline on the diagnosis and management of lower limb peripheral arterial disease is available from the NICE website (from Wednesday 8 August 2012).

2. The following tools are available on the NICE website to help with the implementation of the guideline:

• Costing tools - to help estimate the costs and savings anticipated
• Baseline assessment tool - for assessing compliance against the guideline.
• Clinical audit tools - for monitoring and improving local practice
• Shared learning - examples from practice where people have implemented this guideline

About peripheral arterial disease

1. Peripheral arterial disease (PAD) is a condition in which there is a blockage or narrowing of in one of the main arteries, most commonly the femoral artery in the thigh, or sometimes the iliac artery in the lower abdomen, that carry blood to the legs and arms. The main cause is atherosclerosis, which is narrowing of the arteries caused by fatty deposits on the arterial walls. Asymptomatic PAD is common in people with diabetes.

2. Of those presenting with intermittent claudication over a 5-year period approximately 70 - 80% will remain with stable claudication, 10 - 20% will go on to have worsening symptoms and 5 - 10% will go on to develop critical limb ischaemia. Approximately 10 - 15% die of cardiovascular causes within 5 years and a further 20% will have a non-fatal cardiovascular event

3. Of those who develop critical limb ischaemia there is a high mortality with approximately 25% dying within a year and about 1/3 will require a major lower limb amputation within a year

4. The incidence of PAD increases with age and about 20% of people older than 60 have the condition, although only a quarter of these have symptoms. The incidence of peripheral arterial disease is high among people who smoke, people with diabetes, and people with coronary artery disease. Asymptomatic peripheral arterial disease is common in people with diabetes.

5. Many people will have undetected and asymptomatic PAD. In post-mortem studies, there is a significant incidence of such disease that has never led to lifetime symptoms. The development of symptoms will depend both upon the extent of disease and activity levels of the individual.

6. Peripheral arterial disease may progress to critical limb ischaemia (CLI), with constant and intractable pain preventing sleep, often with ulceration or gangrene of the foot. People with CLI are at risk of losing their leg if they don't receive treatment, and a high proportion present for emergency care. Around 1-2% of people with IC eventually undergo amputation, although the risk is higher (about 5%) in people with diabetes.

7. Even in the absence of symptoms, a reduced blood pressure at the ankle (ankle brachial pressure index or ABPI) - a sign of PAD - is an independent predictor of cardiac and cerebrovascular morbidity and mortality and may help to identify people who would benefit from secondary prevention with aspirin, statins and angiotensin-converting enzyme (ACE) inhibitors. However, treatments for secondary prevention are currently less commonly offered to people with peripheral arterial disease than to those with other cardiac and cerebrovascular risk factors.

8. Self-help measures, including lifestyle changes such as quitting smoking, taking regular exercise and eating a healthy diet, are the most important components in reducing the chance of developing peripheral arterial disease.

9. The management of peripheral arterial disease remains controversial. Treatments include watchful waiting, medical management, exercise training, endovascular treatment and surgical reconstruction.

10. Mild symptoms are generally managed in primary care, with referral to secondary care when symptoms either do not resolve or deteriorate. There are a number of treatment options for those with IC. These include changes in life style (for example, smoking cessation), advice to exercise, management of cardiovascular risk factors (e.g. aspirin, statins) and vasoactive drug treatment (e.g. naftidrofuryl). However, for some people the severe pain that is often associated with intermittent claudication means that their ability to engage in regular exercise, particularly walking, can be severely limited.

11. People with severe symptoms that are inadequately controlled are often referred to secondary care for assessment for endovascular or surgical revascularisation. In recent years there has been a move away from invasive investigation by catheter angiography to non-invasive investigation by duplex ultrasonography, magnetic resonance angiography or computed tomography angiography. Treadmill walking tests and segmental pressures are other commonly used investigations.

12. Endovascular treatments include balloon angioplasty, endovascular stents and a range of new adjunct or alternative treatments and techniques. The new treatments include drug-eluting stents, modified balloons, laser angioplasty, atherectomy, cryotherapy and brachytherapy.

13. Surgical reconstruction may be carried out to unblock or bypass occluded or narrowed arteries. Procedures include aorto-bifemoral, femoro-popliteal and femoro-distal bypass and common femoral endarterectomy. The risks and outcomes of these vary according to the nature of the procedure, the presenting symptoms, comorbidities, and the site and extent of the disease. The current trend is toward less invasive treatment.

14. In 2011 NICE published technology appraisal guidance on cilostazol, naftidrofuryl oxalate, pentoxifylline and inositol nicotinate for peripheral arterial disease (TA223. See: Peripheral arterial disease - cilostazol, naftidrofyryl oxalate, pentoxifylline and inositol nicotinate

About NICE

1. The National Institute for Health and Care Excellence (NICE) is the independent organisation responsible for providing national guidance and standards on the promotion of good health and the prevention and treatment of ill health

2. NICE produces guidance in three areas of health:

• public health - guidance on the promotion of good health and the prevention of ill health for those working in the NHS, local authorities and the wider public and voluntary sector
• health technologies - guidance on the use of new and existing medicines, treatments, medical technologies (including devices and diagnostics) and procedures within the NHS
• clinical practice - guidance on the appropriate treatment and care of people with specific diseases and conditions within the NHS.

3. NICE produces standards for patient care:

• quality standards - these reflect the very best in high quality patient care, to help healthcare practitioners and commissioners of care deliver excellent services
• Quality and Outcomes Framework - NICE develops the clinical and health improvement indicators in the QOF, the Department of Health scheme which rewards GPs for how well they care for patients

4. NICE provides advice and support on putting NICE guidance and standards into practice through its implementation programme, and it collates and accredits high quality health guidance, research and information to help health professionals deliver the best patient care through NHS Evidence.