Introduction to Restless Legs Syndrome

The first description of Restless Legs Syndrome (RLS) was provided in 1685 by Sir Thomas Willis. The current name for this sleep and movement disorder, "restless legs syndrome", was coined in 1945 by Karl Axel Ekbom, a Swedish neurologist and surgeon. It has only been within the past decade, however, that doctors have become more aware of restless legs syndrome and have gained a better understanding of the symptoms, diagnosis, and management of this disorder.

Restless legs syndrome is a chronic, progressive condition which varies widely in degrees of severity and rate of progression. The primary clinical feature of restless legs syndrome is akathisia, an inability to remain in a resting or inactive position without the irresistible urge to move the legs due to strange sensations which lead to motor restlessness and muscular quivering. Sometimes, the individual may report a feeling of pain but typically patients experience paresthesia which is abnormal touch sensation in the absence of an external stimulus, and dysesthesia which is a distortion of the sensation of touch. Patients gave many descriptions for this sensation, including a "creepy-crawly", "prickly", "tingly" feeling in their legs which brings on the urge to move the legs.

Symptoms of restless legs syndrome are worse with prolonged inactivity (e.g., sitting quietly) and they are reduced or relieved by voluntary movement of the affected leg. Although the need to move the legs is involuntary, the movement or activity that the individual chooses to relieve the urge to move is voluntary. Such activities are many and include pacing, stretching the legs, or marching in place. Ignoring or resisting the urge to move one's legs may lead to intensification of the feeling and result in dyskinesia, involuntary movements or jerking motions of the leg (and sometimes of the arms in more advanced restless legs syndrome). These movements can occur during the day or night and disappear with voluntary movement. It is estimated that approximately 50% of individuals seeking medical help for restless legs syndrome experience dyskinesia.

One of the hallmark characteristics of restless legs syndrome is that the severity of the restlessness and leg movement is always worst in the evening and into the night. This has led researchers to believe that restless legs syndrome may be related to the circadian mechanism in the body which regulates many aspects of metabolism, physiology and behavior in humans in a 24 hour period. This distinctive pattern of symptoms being so highly correlated with a particular period of the day is unique to restless legs syndrome.

Although restless legs syndrome is not a life-threatening condition, it may have a significant impact on a patient's quality of life. For example, patients with restless legs syndrome may experience sleep disturbances finding it difficult to fall asleep as well as to stay asleep at night due to restlessness and many short or prolonged awakenings. This results in daytime fatigue, a reduced ability to concentrate, and difficulties functioning in the work or home environment. In addition to sleep disturbances, patients with restless legs syndrome may also experience headaches, depression, reduced sexual desire, hypertension, and heart problems more frequently than people without restless legs syndrome. In addition, a significant source of frustration stems from the fact that many patients think that their symptoms are too mild to get treated or that their condition is untreatable.

Restless leg syndrome varies widely in the intensity and frequency of symptoms, with some patients experiencing symptoms as infrequently as once a month and even then only in stressful conditions (e.g., sitting for prolonged period of time in a theater), others may suffer nightly causing them to spend many hours pacing and in constant movement. Patients with milder symptoms tend to experience them intermittently for years. Other patients may experience intermittent symptoms initially but then progress quickly to daily presentation.