Restless Legs Syndrome

What is Restless Legs Syndrome (RLS)?

RLS is a curious neurological disorder marked by an irresistible urge to move due to strange sensations, most commonly in the legs. These uncomfortable sensations may be described as tingling, burning, aching, grabbing, or a "creepy-crawly" feeling analogous to worms crawling underneath the skin. These feelings are usually associated with an urge to move, typically by walking around, rocking, shaking, or stretching. The different movements that patients choose to reduce their discomfort are under voluntary control and can be suppressed. However, suppression may greatly increase discomfort. Patients with RLS also may have involuntary movements in the legs. Typically these are brisk movements with a sudden jerk of the leg. What makes RLS unique is that these uncomfortable feelings are worsened by rest, lying down or sitting, and significantly improved by movement. Symptoms of RLS are typically worse in the evening and at night, which may interfere with falling asleep or staying asleep.

What causes RLS?

It is estimated that up to 10% of the population in the US is affected by RLS. Middle-aged adults and the elderly are most commonly affected, although cases involving children and adolescents also occur. Symptoms generally get worse over time. In about half of the time cases, RLS runs in families. It is frequently passed from parent to child and equally affects men and women. In other cases, it is associated with certain medical conditions, like anemia, diabetes, kidney disease, or pregnancy. RLS may first come on or get worse during pregnancy. However, within weeks after delivery the symptoms may go away and not reappear for many years. Caffeine and certain drugs used to treat depression or vomiting have also been noted to cause RLS. The exact cause of RLS is unknown; however, it may be related to a problem with dopamine. Dopamine is a natural brain chemical involved in controlling movements. A decrease in dopamine is believed to be the cause in PD. Because of this relationship, many medicines used in PD are also used in RLS.

How is RLS recognized?

RLS is considered a sleep disorder because it interferes with sleep and causes sleep deprivation. Like many sleep disorders it is often under-reported by patients and often not recognized by doctors. Diagnosis of RLS is mainly based on information given by the patient's bed partner regarding sleep problems. In addition, a sleep study known as polysomnogram may help with the diagnosis. While the patient sleeps special devices record sleeping patterns, breathing, oxygen levels, and movements. IN 70 to 90% of patients with RLS, the sleep study will show an associated condition called periodic limb movements of sleep (PLMS). These movements are repetitive contractions of the legs that typically recur at intervals of 15 to 40 seconds during sleep. PLMS are particularly common in the elderly; more than 30% of people over age 65 have them. In fact, 70% to 80% of elderly people have more than five periodic limb movements per hour of sleep on some nights. Because of the increase of PLMS with age, a finding of PLMS on a sleep study is more strongly suggestive of RLS in young people.

What treatment is there for RLS?

Several different types of medications are used for the treatment of RLS. Carbidopa/Levodopa, pramipexole and ropinrole- medications also are used for the treatment of PD-are commonly used and highly effective. The recent study by Stiasny-Koloser suggests that another drug in this same class, cabergoline, may also be promising. Alternative classes of medicine include certain types of sedatives, certain drugs used to control convulsions and for severe cases, narcotics. An evaluation with a neurologist will help in finding the best individual medical treatment. Talk with your health care provider if you are having difficulty sleeping. A good night's sleep is important for good health.

© American Academy of Neurology