Restless legs syndrome

The restless legs syndrome (RLS, also known as Ekbom's syndrome) (1) is a common sensorimotor disorder - the adult prevalence figures for this syndrome are between 5 and 29 per cent (2)

Patients complain of unpleasant sensations experienced predominantly in the legs and rarely in the arms. The symptoms occur only at rest and become more pronounced in the evening or at night.

There is often a strong urge to move the limbs, resulting in only temporary relief of symptoms. The disorder is characterised by periodic leg movements during sleep. These movements may interfere with sleep.

The disorder is associated with a condition known as periodic leg movements during sleep (PLMS). Around 80% of the patients with RLS have PLMS (although less than 50% of PLMS patients have RLS) (3). These movements may interfere with sleep and patients may present with complains of insomnia or fatigue as initial symptoms (1).

The underlying pathophysiology of RLS is not fully recognized. It appears to be associated with

• abnormalities of the dopaminergic neurons
• reduced iron stores specially in the brain (4)

Large-scale study groups in Europe and the US have identified several factors which are associated with RLS:

• high body-mass index
• lower income
• smoking
• lack of exercise
• low alcohol consumption
• diabetes mellitus (5)

Reference:

• (1) Earley C.J. Restless legs syndrome. NEJM 2003;348:2103-210.
• (2) Prescriber (2003), 14 (18).
• (3) Bayard M et al. Restless legs syndrome. AFP 2008;78(2)
• (4) Merlino G. et al. Restless legs syndrome: differential diagnosis and management with rotigotine. Neuropsychiatr Dis Treat. 2009;5:67–80
• (5) RLS-UK/Ekbom Syndrome Association. What is Restless legs syndrome?