Restless Legs Syndrome, Willis-Ekbom Disease

Researchers May Have An Explanation For Restless Legs Syndrome

Willis-Ekbom Disease (WED) – first acknowledged by neurologist Dr. Thomas Willis in 1685 and later described as a syndrome by Dr. Karl Ekbom in 1944 – is a neurological condition associated with an abnormal sensation in the extremities. The disruptive condition is commonly known as Restless Legs Syndrome (RLS).

Restless legs is characterized by a persistent, irresistible urge to move one’s body in an effort to cease an uncomfortable or abnormal feeling – described as an unscratchable itch, tickling, or crawling sensation – permeating throughout the legs. Often times the disorder can also affect the arms, torso, head, and even in rare cases phantom limbs. Moving the affected body part provides temporary relief. Some suffers can have periodic limb movement disorder – where the limb involuntarily jerks or kicks.

The sensation typically begins or intensifies during points of relaxation – while sitting, reading, or trying to sleep – and is found to be most disruptive during nocturnal hours. RLS/WED affects an estimated five percent of the general population, and 10 percent of those over 65.

Several theories suggest the condition may be part of a spectrum, as people can suffer from an infrequent, minor version versus those who suffer to the point where the restlessness impairs their sleep and quality of life significantly.

In the last 20 years, a substantial amount of research has been dedicated to RLS/WED, defining its pathology in hopes of determining the cause and improving treatment options.

Johns Hopkins researchers believe they may have discovered an explanation for the sleepless nights associated with restless legs syndrome/Willis-Ekbom disease, according to their news release.

From the preexisting research, there appears to be three factors which are pertinent to the disease: concentrations of iron in the brain, dopamine concentrations, and genes.

It’s been long thought by neurologists that RLS/WED is related to a dysfunction in the way the brain uses the neurotransmitter dopamine, a neurochemical used by brain cells to communicate and produce smooth, intentional movements. Disruption of these signals results in involuntary movement. Drugs that increase dopamine levels are used to treat RLS/WED, but studies have shown they don’t significantly improve sleep.

A study – published in the May issue of the journal Neurology – led by Richard P. Allen, PhD, an associate professor of neurology at the Johns Hopkins University School of Medicine, suggests there is a link between glutamate and restless legs.

Using an MRI (magnetic resonance imaging) to scan the brains of participants, Allen and his associates found abnormally high levels of glutamate – a neurotransmitter involved in arousal, a major mediator of excitatory signals associated with cognition, memory, and learning – in the images of those with the restless condition.

Researchers specifically measured the glutamate activity in the thalamus – the area of the brain associated with regulation of consciousness, sleep, and alertness – and reviewed the images of 28 people with moderate symptoms of RLS/WED and 20 without, taken during a two-day sleep study. It was found the higher the levels of glutamate the worse the RLS/WED suffers sleep.

According to Allen, “We may have solved the mystery of why getting rid of patients’ urge to move their legs doesn’t improve their sleep. We may have been looking at the wrong thing all along, or we may find that both dopamine and glutamate pathways play a role in RLS.”

The study was funded in part by the National Institutes of Health’s National Institute of Neurological Disorders and Stroke, the National Institute on Aging, and the National Center for Research Resources.

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