What is restless leg syndrome?
restless leg syndrome (which is sometimes referred to as restless legs syndrome, rls or rls syndrome) is a relatively common sleep disorder and central nervous system disorder that is characterized by uncomfortable sensations in the legs, often resulting in an uncontrollable urge to move the legs.
Feelings are often described as itching, tingling, crawling, gnawing or simply painful and can range from being quite mild to severe. Although normally appearing in the calf area, feelings can arise in any part of the leg from the foot up to the thigh and may be present in one or both legs. In some cases these feelings may also be present in the arms and, in rare cases, in the face, torso or groin area.
restless leg syndrome is most acute during periods of inactivity, for example when lying in bed, sitting watching television, sitting at a desk working or riding in a car.
In about eighty percent of cases, restless leg syndrome sufferers also experience a related sleep disorder called periodic limb movement disorder (PLMD), which is characterized by an involuntary jerking or bending of the legs during sleep. This involuntary movement typically occurs hundreds of times every night at intervals ranging from a few seconds up to about a minute and often wakes the sufferer and, more often than not, his or her bed partner.
Although many sleep disorders such as insomnia, sleep apnea and narcolepsy are well know and documented within the medical community, restless leg syndrome is often not taught in medical school at all and a recent study showed that many doctors only correctly diagnosed restless leg syndrome in one case out of four. This failure to correctly diagnose the condition has serious consequences as, left untreated, severe cases can lead to depression and have even been known to result in suicide.
What causes restless leg syndrome?
The exact causes of restless leg syndrome are unknown although studies suggest that it is related to a deficiency in dopamine – a chemical that carries signals between the nerve cells in the body responsible for controlling movement.
In addition, studies carried out at John Hopkins and Pennsylvania State College show evidence of iron deficiencies in the brains of sufferers. These studies do not reveal any indication of brain abnormality or damage and further suggest that the lack of iron within the brain cells simply results from an insufficiently high intake of iron as part of the diet.
There is also good evidence to suggest a genetic cause of restless leg syndrome as it has been shown to run in families. Indeed, one study suggests that a family history of restless leg syndrome is present in half of all diagnosed cases.
That there is a genetic basis for restless leg syndrome sleep disorder is also evidenced by a further recent study that suggests that a gene present on the 12q chromosome may play a part in susceptibility to restless leg syndrome. It is however early days in this area of study and further investigation will be necessary before any firm conclusions are drawn.
Finally, there is some evidence to suggest a connection between restless leg syndrome and attention-deficit hyperactivity disorder (ADHD).
What are the different types of restless leg syndrome?
There are two types of restless leg syndrome sleep disorder:
- Primary RLS. Primary RLS, which accounts for some forty to sixty percent of all cases, is an instance of restless leg syndrome in which no other condition can be said to contribute towards the condition.
- Secondary RLS. Secondary RLS is said to be present when restless leg syndrome can be attributed, at least in part, to an underlying condition.
There are a number of conditions that can trigger secondary rls including:
- Iron deficiency.
- Anemia – a deficiency of red blood cells.
- Chronic disease – such as kidney disease, diabetes or rheumatoid arthritis.
- Peripheral Neuropathy – a disease of the peripheral nerves that is marked by muscle weakness, pain, and numbness.
- The presence of caffeine.
- Pregnancy – about one in four women will experience transitory rls during pregnancy. It normally appears during the third trimester, peaks during the seventh and eight months of pregnancy and disappears after delivery.
- Stress, diet and environmental factors can also trigger rls in some cases.
- Medication – including certain H2-histamine blockers such as Zantac and Tagamet and antidepressants such as Elavil.
Who suffers from restless leg syndrome?
Approximately five to ten percent of the population suffer to some degree from restless leg syndrome (in the US this amounts to about 12 million people), although in most cases the majority of symptoms are manageable.
Both men and women of all ages are susceptible, although restless leg syndrome is more commonly seen as a problem in middle age and tends to worsen as you get older. In younger sufferers the condition is often simply put down to “growing pains” or is considered to be a case of “hyperactivity”.
This sleep disorder also tends to run in families and documented cases suggest that there may also be racial or ethnic factors associated with the condition.
What are the symptoms of restless leg syndrome?
Restless leg syndrome symptoms can range from being relatively mild to incapacitating and can also fluctuate. In some sufferers for example rls symptoms may be quite severe for several weeks or months and then disappear altogether, re-appearing months or years later.
Sufferers frequently complain of an uncomfortable feeling in one or both legs including itching, tingling, crawling, gnawing or simple pain and have an uncontrollable urge to move their legs.
In many cases, restless leg syndrome is accompanied by a related sleep disorder known as periodic limb movement disorder (PLMD) in which sufferers experience involuntary jerking or bending of the legs during sleep, often sufficient to wake them from sleep.
RLS, or the combination of both RLS and PLMD, results in sufferers finding it very difficult to get to sleep, or to remain asleep, and so they also experience excessive tiredness during the day.
RLS and PLMD together represent one of the leading causes of insomnia.
What is the best restless leg syndrome treatment?
In mild cases the best treatment for restless leg syndrome is often a combination of exercise, leg massage (including acupressure), hot baths and the application of either heated pads or ice packs.
In addition, eliminating caffeine from the diet and practicing relaxation, meditation and yoga can be very beneficial.
In all cases of rls, levels of iron in the blood should be checked and, where necessary, iron supplements given.
In moderate to severe cases the treatment for restless leg syndrome may necessitate the use of drugs. There is no single drug recommended for the treatment of rls and restless leg syndrome medications will vary from case to case and depend upon a variety of factors including other pre-existing or coexistent conditions and any other medication being taken. There are, however, four main classes of medication for restless leg syndrome:
- Benzodiazepines. Low dose benzodiazepine treatment acts to suppress the central nervous system. Commonly used drugs include clonazepam (Klonopin) and temazepam (Restoril).Benzodiazepines have a number of common side-effects including headache, heartburn, diarrhea, dizziness, weakness and dry mouth. In particular, however, they can add to daytime tiredness and should not therefore by as rls medication by people who also suffer from sleep apnea.
- Dopaminergic agents. Dopaminergic agents enhance the action of dopamine in the brain and are some of the most favored drugs for treating restless leg syndrome. Many of these drugs are already well known and approved for the treatment of Parkinson’s disease and, in May 2005, one drug in this class – ropinirole HCL (Requip) – became the first and only drug to be approved by the US Food and Drug Administration (FDA) for the treatment of restless leg syndrome.Other commonly used restless leg syndrome medicine in this class includes pramipexole (Mirapex) and pergolide (Permax). Side-effects can include nausea, drowsiness, dizziness and vomiting.In August 2004 a study at the John Hopkins University in Baltimore showed that Requip for restless leg syndrome reduced involuntary leg movements by up to seventy five percent.
- Anticonvulsants. In cases where dopaminergic agents fail or, or where peripheral neuropathy is also present, anticonvulsants such as carbamazepine (Carbatrol, Epitol, Equetro, Tegretol and Tegretol-XR) and gabapentin (Neurontin) may be prescribed.
- Opioids. In severe cases opioid pain killers/relaxants may be prescribed. These include codeine, hydrocodone and ramadol.
In addition to restless leg syndrome medication, an increasing popular non-drug treatment for restless leg syndrome is transcutaneous electric nerve stimulation which is applied to the feet or legs for about fifteen to thirty minutes before going to bed.