What are restless legs syndrome?
Restless legs syndrome (RLS), also called Willis-Ekbom disease, causes unfriendly or uncomfortable sensations in the legs and a tempting urge to move them. Symptoms usually appear in the late afternoon or evening, and are usually more severe at night when a person is resting, such as when sitting or lying in bed. They can also occur when someone is inactive and sitting for long periods (for example, when traveling by plane or watching a movie). Since symptoms can increase in severity during the night, it may be difficult to fall asleep or go back to sleep after waking up. Moving the legs or walking normally alleviates the discomfort, but the sensations often recur once the movement stops. RLS is classified as a sleep disorder because symptoms are triggered by resting and trying to sleep, and as a movement disorder, people are forced to move their legs to relieve symptoms. However, it is best characterized as a sensory neurological disorder with symptoms that arise from within the brain itself.
RLS is one of several disorders that can cause exhaustion and daytime sleepiness, which can strongly affect mood, concentration, work, and school performance, and personal relationships. Many people with RLS report that they are often unable to concentrate, have memory problems, or are unable to perform daily tasks. Raw moderate to severe RLS can lead to an approximately 20 percent decrease in work productivity and can underwrite depression and anxiety. It can also make travel difficult.
It is estimated that up to 7-10 percent of the US population may have RLS. RLS occurs in both males and females, though women are more likely to have it than men. It can start at any age. Many people who are severely affected are middle-aged or older, and symptoms tend to become more frequent and last longer with age.
More than 80 percent of people with RLS also experience periodic limb movement during sleep (PLMS). PLMS is characterized by involuntary jerking or jerking movements in the legs (and sometimes arms) during sleep, which usually occur every 15 to 40 seconds, sometimes during the night. Although many people with RLS also develop PLMS, most people with PLMS do not experience RLS.
Fortunately, most cases of RLS can be treated with non-drug therapies and, if necessary, with medications.
Types of restless legs syndrome
There are two main types of SPI:
Primary or idiopathic RLS
Idiopathic means the cause is unknown.
It is the most common type and has the next characteristics:
- It usually begins before age 40
- It can start from childhood
- It may have a genetic cause
- Once primary RLS begins, it tends to last a lifetime
Symptoms can be sporadic or gradually worsen and become more frequent over time.
In mild cases, the person may not have symptoms for a long time.
A secondary disorder is caused by an additional disease or condition.
Secondary RLS usually begins after age 45 and is not usually inherited. This type of SPI is clearly different:
- The onset is sudden
- Symptoms do not usually get worse over time
- Symptoms can be more severe
Illnesses and symptoms that can trigger secondary RLS include:
- Lack of iron
- Renal insufficiency
- Parkinson’s disease
- The pregnancy
- Rheumatoid arthritis
Exactly how Restless legs syndrome occurs is not well understood, but it may be related to the way the body processes dopamine, a neurotransmitter that plays a role in controlling muscle movements. Some medications, such as selective serotonin reuptake inhibitors (SSRIs) and antidepressants, can trigger RLS. These drugs affect the activity of dopamine.
It is also related to pregnancy. About 20 percent of women experience RLS during the last trimester of pregnancy, although the reasons are unclear.
Periodic Limb Movement Disorder (PLMD)
PLMD is a also related sleep disorder, sometimes termed periodic limb (leg) movement during sleep (PLMS). In people with PLMD, the limbs twitch or shake uncontrollably while they sleep. It is also careful a type of sleep disorder. Movement can cause the individual to wake up frequently during the night and this can undermine the quality and duration of sleep. It can cause SPI.
Symptoms of restless legs syndrome
The Restless Legs Syndrome International Study Group described the following symptoms of restless legs syndrome (RLS):
Strange itching, tingling, or “crawling” sensations occur deep in the legs; These sensations can also occur in the arms.
An urgent need to move the limbs to alleviate these sensations.
Restlessness: Walking on the floor, tossing and turning, rubbing legs
Symptoms can occur only when lying down or sitting down. Sometimes persistent symptoms get worse when lying down or sitting and improve with activity. In very severe cases, symptoms may not improve with activity.
Other symptoms of RLS include the following:
Sleep disturbances and daytime sleepiness.
Involuntary, repetitive, periodic, and jerky movements of the limbs occur during sleep or while you are awake and at rest. These movements are called periodic movements of the legs during sleep or periodic movement of the limbs disorder. Up to 90% of people with RLS also have this disorder.
In some people with RLS, symptoms do not occur every night but come and go. These people may go weeks or months without symptoms (remission) before symptoms return.
Causes of restless legs syndrome
Most of the time, the cause of RLS is a mystery. There may be a genetic tendency and an environmental trigger.
More than 40 percent of people with RLS have a family history of the condition. In fact, there are five genetic variants associated with RLS. When it is hereditary, symptoms usually begin before the age of 40.
There may be a connection between RLS and low iron levels in the brain, even when blood tests show that your iron level is normal.
RLS may be related to a disruption in dopamine pathways in the brain. Parkinson’s disease is also related to dopamine. That may clarify why many people with Parkinson’s also have RLS. Some of the same drugs are used to treat both conditions. Research on these and other theories is ongoing.
It is possible that certain substances such as caffeine or alcohol can trigger or intensify symptoms. Other potential causes include medications to treat:
Primary RLS is not related to an underlying condition. But RLS can actually be a consequence of another health problem, such as neuropathy, diabetes, or kidney failure. When that’s the case, treating the main condition can solve RLS problems.
Diagnosis of restless legs syndrome
There is no single test to diagnose restless legs syndrome.
The diagnosis will be based on your symptoms, medical and family history, a physical exam, and test results.
Your GP should be able to diagnose restless leg syndrome but can refer you to a neurologist if there is any doubt.
There are 4 main criteria that your GP or specialist will look for to confirm a diagnosis.
- An irresistible urge to move your legs, typically with an uncomfortable sensation, such as itching or tingling
- Your symptoms occur or are worse when you are resting or inactive
- Your symptoms are relieved by moving or rubbing your legs
- Your symptoms get worse in the afternoon or evening
- Assess your symptoms
- Your GP or specialist will ask about the pattern of your symptoms to help assess their severity
For example, they may ask you:
- How often do you have symptoms?
- How unpleasant you find your symptoms
- If your symptoms cause significant distress
- If your sleep is interrupted, making you feel tired during the day
- Keeping a sleep diary can help your doctor evaluate your symptoms
You can use the diary to record your daily sleeping habits, such as the time you go to bed, the time it takes to fall asleep, how often you wake up during the night, and episodes of fatigue during the day.
Mild symptoms of restless legs syndrome can usually be treated through lifestyle changes.
- Establish a regular sleep pattern
- Avoiding stimulants, such as caffeine, alcohol, or tobacco, at night
- If your symptoms are more severe, you may need medicine to control them
Your GP may refer you for blood tests to settle or rule out possible fundamental causes of restless legs syndrome.
For example, you may have blood tests to rule out conditions such as anemia, diabetes, and kidney function problems.
It is particularly important to know your blood iron levels because low iron levels can sometimes cause secondary restless legs syndrome.
Low iron levels can be treated with iron tablets.
If you have restless legs syndrome and your sleep is severely disrupted, sleep tests, such as a suggested immobilization test, may be recommended.
The test involves lying on a bed for a set period of time without moving the legs while monitoring the involuntary movements of the legs.
On occasion, polysomnography may be recommended. This is a test that measures your breathing rate, brain waves, and heartbeat over the course of one night.
The results will confirm if you have periodic limb movement during sleep (PLMS).
Treatment for restless legs syndrome
Treatment of restless legs syndrome is contingent on the intensity of the symptoms. Treatment should be considered if the quality of life is affected by insomnia and excessive daytime sleepiness. In cases of RLS due to ongoing medical conditions, specific treatment is also necessary.
Non-pharmacological treatments. Non-drug treatments are tried first, particularly if symptoms are mild. Non-drug treatments include:
- Exercise regularly, such as riding a bike / stationary bike or walking, but avoid heavy/intense exercise a few hours before bed.
- Follow good sleep habits, such as avoiding reading, watching television, or using a computer or telephone while lying in bed; get 7 to 9 hours of sleep and follow other healthy sleep habits. Not getting enough sleep can make Restless legs syndrome symptoms worse.
- Avoid or limit caffeinated harvests (coffees, teas, colas, chocolates, and some medications [check labels]), nicotine, and alcohol.
- Apply a heating pad, cold pack, or rub the legs to temporarily relieve leg discomfort. Also consider massage, acupressure, ambulatory, light stretching, or other relaxation techniques.
- Soak in a hot tub.
- Try magnesium supplements. Can be useful.
- Reduce stress as much as possible. Try meditation, yoga, soft music, or other options.
- Iron supplements. Iron deficiency is a reversible cause of RLS. If blood tests reveal that you have low iron levels, your doctor may recommend taking an iron supplement.
Prescription drugs. When Restless legs syndrome symptoms are recurrent or severe, your healthcare provider will likely prescribe medications to treat the disorder. Medication options include:
Dopamine agonists switch the urge to move, sensory symptoms in the legs, and reduce involuntary jerking of the legs throughout sleep. Ropinirole (Requip), pramipexole (Mirapex), and rotigotine patch (Neupro) are FDA-approved dopamine agonists used for RLS.
Anti-seizure medications can slow or block pain signals from the nerves in the legs. Examples include gabapentin enacarbyl (Horizant), gabapentin (Neurontin), and pregabalin (Lyrica). These medications are particularly effective in patients with painful RLS due to neuropathy. Gabapentin enacarbyl is the only drug in this class that is FDA approved for Restless legs syndrome. However, the others can be effective.
Benzodiazepines, particularly clonazepam, are sometimes prescribed for RLS but are generally reserved for more severe cases due to their addictive potential and side effects, including daytime sleepiness.
Opioids, such as methadone or oxycodone, can be used to relieve the symptoms of RLS, but due to the risk of addiction, they are generally not prescribed unless the case is plain and other medications have not been effective.
You and your physician will discuss the treatment that might be best for you.
Although RLS does not lead to other serious conditions, symptoms can range from mildly bothersome to disabling. Many people with RLS have a hard time falling asleep or staying asleep.
Severe Restless legs syndrome can cause a marked deterioration in the quality of life and can lead to depression. Insomnia can cause excessive daytime sleepiness, but RLS can interfere with napping.