In 2002, The International Restless Legs Syndrome Study Group produced the following 4 criteria for the diagnosis of RLS;

• Uncontrollable urge to move the legs, usually with disturbed sensation

• Onset or exacerbation with rest

• Relief with movement

• Circadian pattern

1. Urge to move the legs, usually with dysaesthesiae (disturbed sensation),

An urge to move the legs, usually accompanied or caused by uncomfortable or unpleasant sensations in the legs (sometimes the urge to move is present without the uncomfortable sensations and sometimes the arms or other body parts are involved in addition to the legs).

About 10% of patients report having the urge to move without any other related sensations, but the majority of people feel uncomfortable sensations or pain. Most have difficulty describing their RLS sensation and use broad terms such as ‘uncomfortable’ and ‘inside the leg’.

Although it was originally taught that pain was not a part of RLS, new research shows that more than 50% of patients describe pain as part of their problem.

2. Onset or exacerbation with rest

The urge to move and/or unpleasant sensations begin or worsen during periods of rest or inactivity particularly with lying down or sitting. Rest with inactivity triggers the symptoms in a sufferer, usually fairly quickly, and symptoms worsen if the patient does not move. Rest with inactivity almost always involves sitting or lying and these positions seem to be specific for setting off the problem. Long journeys by car or plane are a common trigger as is just sitting down in the evening or going to bed.

The urge to move or unpleasant sensations are partially or totally relieved by movement such as walking or stretching, at least as long as the activity continues. Relief with movement usually begins immediately or very soon after activity begins. It may not be complete and sometimes patients are aware that the RLS symptoms are just damped down but still in the background. Some patients find that rubbing the legs or taking hot or cold baths can help. As the RLS becomes more severe patients find that the degree of relief they can get from movement decreases until no amount of movement helps.

4. Circadian pattern

The urge to move or unpleasant sensations are worse in the evening or night than during the day, or only occur in the evening or night. (When symptoms are very severe they may be constant and the worsening at night may not be noticeable, but night worsening must have been present at some stage previously).

Most patients will have their symptoms in the evening or at night (the peak activity is in the hours immediately after midnight), but in patients with advanced RLS there may be symptoms throughout the 24 hours without variation.

The main problem with RLS is the sleep disturbance that it causes, not only for the sufferer, but also for the spouse or partner. I have seen a patient who was being forced out of bed 12 or 13 times a night, and who was almost suicidal because of lack of sleep.

RLS seems to run in families (and some genes for this have been isolated). It can occur at any age, even in children where it may be misdiagnosed as “growing pains”. It is more common in women and is much commoner during pregnancy (up to 30% of women may suffer), although it tends to diappear after the baby is born.