Restless legs syndrome (RLS), also known as Willis-Ekbom disease (WED), is a common condition affecting the nervous system.
It causes an overwhelming, irresistible urge to move the legs, and occasionally the arms. It also causes an unpleasant feeling in the feet, calves and thighs, which is often felt as a crawling or creeping sensation. The sensation is often worse in the evening or at night.
Restless legs syndrome is also associated with involuntary jerking of the legs and arms, known as periodic limb movements.
Symptoms can vary from being mild to severe. In severe cases, the condition can be distressing and can disrupt daily activities.
Some people have symptoms now and again, while others have them every day.
Causes of RLS
In the majority of cases, there is no obvious cause of restless legs syndrome. Doctors may refer to this as idiopathic RLS, or primary RLS. This type of restless legs syndrome can run in families.
Some neurologists (experts in treating conditions that affect the nervous system) share the opinion that symptoms may have something to do with how the body handles a chemical called dopamine. Dopamine plays a role in controlling muscle movement and may be responsible for the involuntary leg movements associated with restless legs syndrome.
Some cases of restless legs syndrome are caused by an underlying health condition, such as iron deficiency anaemia, or kidney failure. Doctors may refer to this as secondary RLS.
There is also a link between restless legs syndrome and pregnancy and around one in five pregnant women will experience symptoms in the last three months of their pregnancy, although it is not clear exactly why. In this case, it often goes away once the woman has given birth.
Mild cases of restless legs syndrome that are not linked to an underlying health condition may not require any treatment other than making a few lifestyle changes, such as:
adopting good sleep hygiene - for example, sleeping regular hours and avoiding alcohol and caffeine late at night
quitting smoking (if you smoke)
exercising regularly during the daytime
If the symptoms are more severe, medication may be needed to regulate the levels of dopamine and iron in the body.
If restless legs syndrome is caused by iron deficiency anaemia, for example, then iron supplements may be all that is needed to treat the symptoms.
Who is affected?
As many as one in ten people are affected by restless legs syndrome at some point in their life.
Women are twice as likely to develop restless legs syndrome than men. The condition is also more common in middle age, but the symptoms can develop at any age, including childhood.
If you are able to address the underlying cause of restless legs syndrome, the symptoms will usually go away.
However, if the cause is unknown, the symptoms can get worse with time and severely affect the person's life. It's not life-threatening, but it can severely disrupt sleep (insomnia) and trigger anxiety anddepression.
The charity Restless Leg Syndrome UK offers support and more information for people affected by restless legs syndrome, and they may be able to put you in touch with others affected by the condition.
Symptoms of restless legs syndrome
Restless legs syndrome (RLS) typically causes an overwhelming urge to move your legs and an uncomfortable sensation in your legs and sometimes arms, chest and face.
A range of different sensations have been reported by people with restless legs syndrome, including:
tingling, burning, itching or throbbing
a 'creepy-crawly' feeling
feeling like fizzy water is inside the blood vessels in the legs
cramping in the calf’s or legs
These unpleasant sensations can often be relieved by moving or rubbing your legs. They can range from mild to unbearable and are usually worse in the evening and during the night.
Some people experience symptoms now and again, while others have them every day. It may be difficult to sit for long periods of time, for example on a long train journey.
Just over half of people with restless legs syndrome also experience episodes of lower back pain.
Periodic limb movements (PLMS)
Over 80% of people with restless legs syndrome also have a condition that is known as periodic limb movements (PLM)
If you have PLM, you will have jerky or twitchy leg movements, usually at night while you are asleep. The movements are involuntary (you have no control over them) and may occur every 10-60 seconds.
The leg movements of PLM can be severe enough to wake up both you and your partner. They may also sometimes occur when you are awake and resting.
Causes of restless legs syndrome
In many cases of restless legs syndrome (RLS) the exact cause is unknown.
When no cause can be found it is known as idiopathic, or primary restless legs syndrome. This can run in families and is most common in people younger than 40.
There is conflicting evidence about the role of a brain chemical called dopamine with restless legs syndrome.
Some people benefit from a type of medication called a dopamine agonist, which raises the levels of dopamine in the brain. This had led to some people arguing that the condition is related to problems with creating and breaking down dopamine in brain cells.
Dopamine levels naturally fall towards the end of the day, which may explain why the symptoms of restless legs syndrome are often worse in the evening and during the night.
Further research into this is needed.
Underlying health condition
Secondary restless legs syndrome can occur as a complication of another health condition, or it can develop as a result of another health-related factor.
For example, you may develop secondary restless legs syndrome if you:
have iron-deficiency anaemia – low levels of iron in the blood can lead to a drop in dopamine, triggering restless legs syndrome
have a chronic (long-term) health condition – such as chronic kidney disease, diabetes, Parkinson’s disease, rheumatoid arthritis, an underactive thyroid gland or fibromyalgia
are pregnant – particularly from week 27 until birth; in most cases, the symptoms disappear within four weeks of giving birth
There are a number of triggers that do not cause restless legs syndrome, but can make symptoms worse. These include medications such as:
lithium (used in the treatment of bipolar disorder)
calcium channel blockers (used in the treatment of high blood pressure)
metoclopramide (used to relieve nausea)
Other reported triggers include:
excessive smoking, caffeine or alcohol
being overweight or obese
lack of exercise
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:
A confident diagnosis can be made if you have all the above symptoms.
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:
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.
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.
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.
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
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
Treating restless legs syndrome
If your restless leg syndrome (RLS) is known to be linked to an underlying cause, then treating that cause can often cure the condition.
For example, iron deficiency can be treated by taking iron supplements, and restless legs syndrome associated with pregnancy usually goes away on its own within four weeks of the birth.
If no obvious cause can be found, then treatment falls into one of two categories:
A number of lifestyle changes may be enough to ease the symptoms of restless legs syndrome. These include:
During an attack of restless legs syndrome, you may find the following measures helpful in relieving symptoms:
A small medical trial carried out in 2011 found that a type of osteopathic exercise technique called positional release manipulation (PRM) could be of benefit to people with restless legs syndrome.
PRM involves holding different parts of the body in position that has been found to reduce feelings of discomfort and pain.
Not all medicines used to treat RLS are licensed in the UK. If a medicine is licensed, it means it has been approved by the Medicines and Healthcare Regulatory Agency (MHRA) as a safe and effective form of treatment.
Unlicensed medicines are not necessarily unsafe. They can be prescribed if a health professional feels that the potential benefit of the medication outweighs any possible risk.
The medicine may be unlicensed because there is not enough commercial interest in marketing it, or because it is awaiting approval for a license. If a medicine is unlicensed, it is up to your GP to decide whether they prescribe it to you.
Dopamine agonists are usually recommended if you are having more frequent symptoms. They include:
These medications can occasionally make you feel sleepy so you should be cautious when driving or using tools after taking them.
Other side effects of these medications include:
You may need to be prescribed a mild opiate-based painkiller such as codeine or tramadol to relieve any pain associated with restless legs syndrome.
Another medication that can be used to both relieve pain and relieve symptoms is gabapentin. Side effects of gabapentin include dizziness and feeling tired and sleepy.
If you are having a particularly severe flare-up of symptoms that is disrupting your sleep, it may be recommended that you take a short-term course of medication to help you sleep.
These types of medications are known as hypnotics and include temazepam and loprazolam.
Hypnotics are usually only recommended to be used on short-term basis (typically no longer than week).
You may find you still feel sleepy or 'hungover' the next morning after taking your medication.
Levodopa may be recommended if you only have symptoms now and again. This is because if you took levodopa every day, there is a high risk that it would actually make your symptoms worse.
Levodopa is available in tablet or liquid form and you should take it once you feel the symptoms of restless legs syndrome coming on.
The medication will make you feel very sleepy, often very suddenly, so you should never drive or use tools or machinery after taking levodopa.
Levodopa can cause nausea, so it is usually combined other medications to reduce the nausea.
Research has found that people with restless legs syndrome are twice as likely to develop cardiovascular disease (CVD) than the population at large. It is not known exactly why.
The more severe the symptoms, the greater the increase in risk.
You can take steps to reduce your risk of CVD, such as regularly exercising, maintaining a healthy weight, quitting smoking if you smoke and eating a healthy diet.
avoiding evening stimulants, such as caffeine, tobacco and alcohol
taking regular, daily exercise – but avoid exercising near bedtime
establishing a regular sleeping pattern – for example, going to bed and getting up at the same time every day; not napping during the day; taking time to relax before going to bed; avoiding caffeine close to bedtime
avoiding medicines that trigger the symptoms or make them worse – if you think your medication is causing your symptoms, continue taking it and make an appointment to see your GP.
massaging your legs
taking a hot bath in the evening
applying a hot or cold compress to your leg muscles
doing activities that distract your mind, such as reading or watching television
relaxation exercises such as yoga or tai chi
walking and stretching
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