Restless Legs Syndrome: Known Knowns and Known Unknowns.

Elena Antelmi,Anna Latorre,Michele Tinazzi,Kailash P Bhatia,Francesca Magrinelli,Daniele Belvisi,Lorenzo Rocchi

doi:10.3390/brainsci12010118

Abstract

Although restless legs syndrome (RLS) is a common neurological disorder, it remains poorly understood from both clinical and pathophysiological perspectives. RLS is classified among sleep-related movement disorders, namely, conditions characterized by simple, often stereotyped movements occurring during sleep. However, several clinical, neurophysiological and neuroimaging observations question this view. The aim of the present review is to summarize and query some of the current concepts (known knowns) and to identify open questions (known unknowns) on RLS pathophysiology. Based on several lines of evidence, we propose that RLS should be viewed as a disorder of sensorimotor interaction with a typical circadian pattern of occurrence, possibly arising from neurochemical dysfunction and abnormal excitability in different brain structures.

Highlights

Restless legs syndrome (RLS) is a common neurological disorder affecting up to 15% of the general population [1,2,3]. It is categorized as a sleep-related movement disorder (MD) due to its peculiar occurrence, usually during or shortly before sleep [4]
Post-mortem, neuroimaging and biohumoral studies have suggested that brain iron deficiency (BID) may play a role in RLS pathophysiology [14]
RLS is classified among sleep-related MDs, namely, conditions characterized by simple, often stereotyped movements occurring during sleep [4]

Summary

Introduction

Restless legs syndrome (RLS) is a common neurological disorder affecting up to 15% of the general population [1,2,3]. It is categorized as a sleep-related movement disorder (MD) due to its peculiar occurrence, usually during or shortly before sleep [4]. RLS is classified as primary (idiopathic, iRLS) or associated with other medical conditions [8]. Post-mortem, neuroimaging and biohumoral studies have suggested that brain iron deficiency (BID) may play a role in RLS pathophysiology [14]. The aim of the present review is to summarize and query some of the current concepts of RLS pathophysiology (known knowns) and to identify open questions (known unknowns), which might drive future research and shed light on this disorder

Why RLS Is Not a Sleep-Related Movement Disorder

Findings

Conclusions and Future Research