Ekbom syndrome - Diagnosing restless legs syndrome

There is no single test for diagnosing restless legs syndrome (RLS). The condition is usually diagnosed based on your symptoms and your previous medical and family history.

The International Restless Legs Syndrome Study Group has identified some basic criteria for diagnosing restless legs syndrome. These are:

• an overwhelming urge to move your legs, usually with an uncomfortable sensation such as itching or tingling
• symptoms occur or worsen when you are resting or inactive
• symptoms are relieved by moving your legs or rubbing them
• symptoms are worse during the evening or at night

A confident diagnosis can be made if you have all the above symptoms.

Blood tests

If your GP suspects that you have restless legs syndrome, they may refer you for a number of blood tests to confirm or rule possible secondary underlying causes. For example, you may have blood tests to rule out health conditions such as anaemia, diabetes and problems with your kidney function.

The most important blood test is to find out the levels of iron in your blood. Low levels of iron can be treated with iron tablets.

Assessing your symptoms

Your GP will also want to ask you about the pattern of your symptoms, to assess whether you have mild, moderate, severe or very severe restless legs syndrome.

They may ask:

• how often your symptoms occur
• how unpleasant you find your symptoms
• if your symptoms cause significant distress
• if your sleep is being disrupted, making you tired during the day

Mild symptoms can usually just be treated by making lifestyle changes. Moderate to very severe restless legs syndrome usually requires medication to bring symptoms under control. Read more about the treatment of restless leg syndrome.

Your symptoms may be assessed using the International RLS severity scale (IRLSS). Your symptoms are given a score out of 40 and if the score is over 15 you will need treatment.

Sleep tests

If you have restless legs syndrome and are experiencing severe disruption to your sleep, sleep tests such as a suggested immobilisation test (SIT) may be offered. A suggested immobilisation test involves lying on a bed for a period of time without moving your legs while any involuntary leg movements are monitored.

Occasionally, polysomnography may be recommended. Polysomnography is a test that measures your breathing rate, brain waves, and heartbeat throughout the course of a night. This type of test will confirm whether you have periodic limb movements of sleep.