Restless legs syndrome
Restless legs syndrome (RLS) is characterized by unpleasant sensations in thelimbs, usually the legs, that occur at rest or before sleep and are relievedby activity such as walking. These sensations are felt deep within the legsand are described as creeping, crawling, aching, or fidgety.
Restless legs syndrome, also known as Ekbom syndrome, Wittmaack-Ekbom syndrome, anxietas tibiarum, or anxietas tibialis, affects up to 10-15% of the population. Some studies show that RLS is more common among elderlypeople. Almost half of patients over age 60 who complain of insomnia are diagnosed with RLS. In some cases, the patient has another medical condition with which RLS is associated. In idiopathic RLS, no cause can be found. In familial cases, RLS may be inherited from a close relative, most likely a parent.
Most people experience mild symptoms. They may lie down to rest at the end ofthe day and, just before sleep, will experience discomfort in their legs that prompts them to stand up, massage the leg, or walk briefly. Eighty-five percent of RLS patients either have difficulty falling asleep or wake several times during the night, and almost half experience daytime fatigue or sleepiness. It is common for the symptoms to be intermittent, disappearing for severalmonths and then returning for no apparent reason. Two-thirds of patients report that their symptoms become worse with time. Some older patients claim tohave had symptoms since they were in their early 20s, but were not diagnoseduntil their 50s. Suspected under-diagnosis of RLS may be attributed to the difficulty experienced by patients in describing their symptoms.
More than 80% of patients with RLS experience periodic limb movements in sleep (PLMS). These random movements of arms or legs may result in further sleepdisturbance and daytime fatigue. Most patients have restless feelings in bothlegs, but only one leg may be affected. Arms may be affected in nearly halfof patients.
There is no known cause for the disorder, but recent research has focused onseveral key areas. These include:
- Central nervous system (CNS) abnormalities. Several types of drugs have been found to reduce the symptoms of RLS.Based on an understanding of how these drugs work, theories have been developed to explain the cause of the disorder. Levodopa and other drugs that correct problems with signal transmission within the CNS can reduce the symptoms of RLS. It is therefore suspected that the source of RLS is a problem relatedto signal transmission systems in the CNS.
- Iron deficiency anemia. The body stores iron in the form of ferritin. There is a relationship between low levels of iron (as ferritin) stored in the body and the occurrence of RLS.Studies have shown that older people with RLS often have low levels of ferritin. Supplements of iron sulfate have been shown to significantly reduce RLSsymptoms for these patients.
A careful history enables the physician to distinguish RLS from similar typesof disorders that cause night time discomfort in the limbs, such as muscle cramps, burning feet syndrome, and damage to nerves that detect sensations orcause movement (polyneuropathy).
The most important tool the doctor has in diagnosis is the history obtained from the patient. There are several common medical conditions that are known to either cause or to be closely associated with RLS. The doctor may link thepatient's symptoms to one of these conditions, which include anemia, diabetesmellitus, disease of the spinal nerve roots (lumbosacral radiculopathy), Parkinson's disease, late-stage pregnancy, kidney failure (uremia), and complications of stomach surgery. In order to identify or eliminate such a primary cause, blood tests may be performed to determine the presence of serum iron, ferritin, folate, vitamin B 12, creatinine, and thyroid-stimulatinghormones. The physician may also ask if symptoms are present in any close family members, since it is common for RLS to run in families and this type is sometimes more difficult to treat.
In some cases, sleep studies such as a polysomnography are undertaken to identify the presence of PLMS that are reported to affect 70-80% of people who suffer from RLS. The patient is often unaware of these movements, since they may not cause him to wake. However, the presence of PLMS with RLS can leave theperson more tired, because it interferes with deep sleep. A patient who alsodisplays evidence of some neurologic disease may undergo electromyography (EMG). During EMG, a very small, thin needle is inserted into the muscle and electrical activity of the muscle is recorded. A doctor or technician usually performs this test at a hospital outpatient department.
The first step in treatment is to treat existing conditions that are known tobe associated with RLS and that will be identified by blood tests. If the patient is anemic, iron (iron sulfate) or vitamin supplements--particularly folate or vitamin B12--will be prescribed. If kidney disease is identified as a cause, treatment of the kidney problem will take priority.
In some people whose symptoms cannot be linked to a treatable associated condition, drug therapy may be necessary to provide relief and restore a normal sleep pattern. Prescription drugs that are normally used for RLS include:
- Benzodiazepines and low-potency opioids. These drugs are prescribed for use only on an "as needed" basis, for patients with mild RLS. Benzodiazepines appear to reduce nighttime awakenings due to PLMS. The benzodiazepine most commonly used to treat RLS is clonazepam (Klonopin, Rivotril). The main disadvantage of this drug type is that it causes daytime drowsiness. It also causes unsteadiness that may lead to accidents, especially for an elderly patient. Opioid analgesics are narcotic pain relievers. Those commonly used for mild RLSare low potency opioids, such as codeine (Tylenol #3) and propoxyphene (Darvocet). Studies have shown that these can be successfully used in the treatment of RLS on a long-term basis without risk of addiction. However, narcotics can cause constipation and difficulty urinating.
- Levodopa (L-dopa) andcarbidopa (Sinemet). Levodopa is the drug most commonly used to treat moderate or severe RLS. It acts by supplying a chemical called dopamine to the brain. It is often taken in conjunction with carbidopa to prevent or decrease side effects. Although it is effective against RLS, levodopa may also causes a worsening of symptoms during the afternoon or early evening in 50-80% of patients. This phenomenon is known as "restless legs augmentation," and if it occurs, the physician will probably discontinue Levodopa for a brief period whilean alternate drug is used. Levodopa can often be reintroduced after a shortbreak.
- Pergolide (Permax). Pergolide acts on the same part of the brain as Levodopa. It is less likely than Levodopa to cause daytime worsening ofsymptoms (occurs in about 25% of patients). However, it is not recommended as the first choice in drug therapy since it causes a high rate of minor sideeffects. Pergolide is often used only if Levodopa has been discontinued.
- High potency opioids. If the symptoms of RLS are difficult to treat withthe above medication, higher dose opioids will be used. These include methadone (Dolophine), oxycodone, and clonidine (Catapres, Combipres, Dixarit). A significant disadvantage of these drugs is risk of addiction.
- Anticonvulsants. Some cases of RLS may be improved by anticonvulsant drugs, such as carbamazepine (Tegretol).
- Combination therapy. Some patients respond well to combinations of drugs such as a benzodiazepine and Levodopa.
Many drugs have been investigated for treatment of RLS, but it seems as though the perfect therapy has not yet been found. However, careful monitoring ofside effects and good communication between patient and doctor can result ina flexible program of therapy that minimizes side effects and maximizes effectiveness.
It is likely that the best alternative medicine will combine both conventional and alternative therapies. Levodopa may be combined with a therapy that relieves pain, relaxes muscles, or focuses in general on the nervous system andthe brain. Any such combined therapy that allows a reduction in dosage of levodopa is advantageous, since this will reduce the likelihood of unacceptablelevels of drug side effects. Of course, the physician who prescribes the medication should monitor any combined therapy. Alternative methods may include:
- Acupuncture. Patients who also suffer from rheumatoid arthritis may especially benefit from acupuncture to relieve RLS symptoms. Acupuncture is believed to be effective in arthritis treatment and may also stimulate those parts of the brain that are involved in RLS.
- Homeopathy. Homeopaths believe that disorders of the nervous system are especially important because thebrain controls so many other bodily functions. The remedy is tailored to theindividual patient and is based on individual symptoms as well as the general symptoms of RLS.
- Reflexology. Reflexologists claim that the brain,head, and spine all respond to indirect massage of specific parts of the feet.
- Nutritional supplements. Supplementation of the diet with vitamin E, calcium, magnesium, and folic acid may be helpful for people with RLS.
Some alternative methods may treat the associated condition that is suspectedto cause restless legs. These include:
- Anemia or low ferritin levels. Chinese medicine will emphasize stimulation of the spleen as a means of improving blood circulation and vitamin absorption. Other treatments may includeacupuncture and herbal therapies, such as ginseng (Panax ginseng) foranemia-related fatigue.
- Late-stage pregnancy. There are few conventional therapies available to pregnant women, since most of the drugs prescribed are not recommended for use during pregnancy. Pregnant women may benefit from alternative techniques that focus on body work, including yoga, reflexology, and acupuncture.
RLS usually does not indicate the onset of other neurological disease. It mayremain static, although two-thirds of patients get worse with time. The symptoms usually progress gradually. Treatment with Levodopa is effective in moderate to severe cases that may include significant PLMS. However, this drug produces significant side effects, and continued successful treatment may depend on carefully monitored use of combination drug therapy. The prognosis (expected outcome) is usually best if RLS symptoms are recent and can be traced toanother treatable condition associated with RLS. Some associated conditionsare not treatable, however. In these cases, such as for rheumatoid arthritis,alternative medicine such as acupuncture may be helpful.
Diet is key in preventing RLS. A preventive diet will include an adequate intake of iron and the B vitamins, especially B12 and folic acid. Strict vegetarians should take vitamin supplements to obtain sufficient vitaminB12. Ferrous gluconate may be easier on the digestive system thanferrous sulfate, if iron supplements are prescribed. Some medications may cause symptoms of RLS. Patients should check with their doctor about these possible side effects, especially if symptoms first occur after starting a new medication. Caffeine, alcohol, and nicotine use should be minimized or eliminated. Even a hot bath before bed has been shown to prevent symptoms for some sufferers.