Lower limb peripheral arterial disease (or peripheral arterial disease for short) is a marker for increased risk of cardiovascular events even when it is asymptomatic. The most common initial symptom of peripheral arterial disease is leg pain while walking, known as intermittent claudication. Critical limb ischaemia is a severe manifestation of peripheral arterial disease, and is characterised by severely diminished circulation, ischaemic pain, ulceration, tissue loss and/or gangrene.

The incidence of peripheral arterial disease increases with age. Population studies have found that about 20% of people aged over 60 years have some degree of peripheral arterial disease. Smoking is also an important risk factor, with people who smoke having a greater risk than people who have never smoked. Incidence is also high in people with coronary artery disease and in people with diabetes, meaning that early diagnosis and management of peripheral arterial disease is important . In most people with intermittent claudication the symptoms remain stable, but approximately 20% will develop increasingly severe symptoms with the development of critical limb ischaemia.

Mild symptoms are generally managed in primary care, with referral to secondary care when symptoms do not resolve or deteriorate. There are several treatment options for people with intermittent claudication. These include advice to exercise, management of cardiovascular risk factors (for example, with aspirin or statins) and vasoactive drug treatment (for example, with naftidrofuryl oxalate).

People with severe symptoms that are inadequately controlled are often referred to secondary care for assessment for endovascular treatment (such as angioplasty or stenting), bypass surgery, pain management and/or amputation.

Rapid changes in diagnostic methods, endovascular treatments and vascular services, associated with the emergence of new sub‑specialties in surgery and interventional radiology, has resulted in considerable uncertainty and variation in practice. This guideline aims to resolve that uncertainty and variation.

In 2018 we reviewed the evidence on tests for diagnosing peripheral arterial disease in people with diabetes and added new recommendations for this group.