Intermittent claudication

What causes intermittent claudication?

Intermittent claudication happens when your leg muscles cannot get enough oxygen-rich blood while you're active. This is usually caused by peripheral arterial disease (PAD), where fatty deposits build up inside the artery walls in a process called atherosclerosis, narrowing the arteries and restricting blood flow to your legs.

Risk factors for PAD include:

• Smoking – the most significant risk factor
• High cholesterol
• High blood pressure
• Diabetes (type 1 or type 2)
• Obesity (a body mass index, or BMI, over 30)
• Chronic kidney disease
• Growing older, particularly from age 50, or from a younger age if you also smoke or have diabetes
• A family history of atherosclerosis, PAD or claudication.

Are there different types of intermittent claudication?

Intermittent claudication can feel slightly different from person to person, depending on which artery is affected and how narrowed it has become.

• Calf pain – the most common site, usually linked to narrowing in the arteries of the lower leg
• Thigh, hip or buttock pain – can happen when the narrowing is higher up, in the arteries of the pelvis or upper leg
• Pain in one leg, or both at the same time – both patterns are common
• Mild to severe pain – how bad the pain is varies between people.

How is intermittent claudication diagnosed?

A GP will usually start by asking about your symptoms and examining your legs, checking your pulses and looking for changes in skin colour or temperature. Possible investigations:

1. Ankle brachial pressure index (ABPI, sometimes called ABI) – comparing the blood pressure in your ankle with the blood pressure in your arm; a difference between the two suggests PAD.
2. Doppler scan, if needed – a scan that listens to the sound of blood flowing through your leg arteries.
3. Further imaging, if needed – such as an ultrasound or MRI scan, usually only if the diagnosis is unclear or your circulation is very poor.

Your GP will also assess your wider risk of heart attack and stroke by checking your blood pressure and cholesterol, and asking whether you smoke.

How is intermittent claudication treated?

Treatment aims to improve blood flow to your legs and to reduce your risk of heart attack and stroke, since the same narrowed arteries raise both risks.

• Supervised exercise – a programme of about 2 hours a week for 3 months, walking to the point of pain and resting, to build up your walking distance over time
• Stopping smoking – smoking speeds up artery narrowing, so quitting is one of the most important changes you can make. Smoking cessation support and medications can be accessed from your local pharmacy
• Healthy diet and weight – eating a healthy balanced diet and losing weight if you're overweight
• Antiplatelet medicine – such as aspirin or clopidogrel, to reduce the risk of blood clots
• Statins – cholesterol-lowering medicine that can also improve walking distance and pain-free walking time
• Blood pressure or diabetes medicine, if needed – to manage other risk factors.

If exercise and medicine do not improve your symptoms enough, or your leg pain is severe, you may be offered a procedure to improve blood flow: an angioplasty (using a small balloon to widen the narrowed artery) or a bypass operation (creating a new route for blood to flow around the blockage).

When should you see a doctor?

Consult your GP if you notice repeated episodes of pain, cramping or tiredness in the legs which comes on with walking or exercise and eases with rest. Contact a GP urgently (or call 111) if you notice the following symptoms, as they can indicate a serious complication known as critical limb ischaemia:

• Leg pain that develops quickly, or suddenly gets worse
• Burning pain in your legs or feet that continues even when you're resting
• Skin on your legs or feet turning pale, blue, shiny or unusually smooth (colour changes can be harder to see on brown and black skin)
• Wounds, ulcers or sores on your feet or legs that will not heal
• Numbness, coldness or swelling in your toes or lower leg