Sleep Medicine and Psychophysiology (수면정신생리)

KOREAN ACADEMY OF SLEEP MEDICINE (대한수면의학회)
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The Pathophysiology of Restless Legs Syndrome/Willis-Ekbom Disease

하지불안증후군/윌리스-엑봄병의 병태생리

  • Cyn, Jaegong (Yong-In Mental Hospital, Yong-In Mental Psychiatric Research Institute)
  • 신재공 (용인정신병원, 용인정신의학연구소)
  • Received : 2021.12.06
  • Accepted : 2021.12.18
  • Published : 2021.12.31
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Abstract

Restless Legs Syndrome/Willis-Ekbom Disease (RLS/WED) is a sleep disorder characterized by sensorimotor symptoms such as unpleasant sensations before sleep, akathisia, and periodic limb movements during sleep. It is also closely related to hyperarousal and is often accompanied by insomnia. Although the mechanism is not clear, the understanding of etiology and pathophysiology has greatly expanded through recent advances in genetic and neurobiological research. The most important pathophysiology of RLS/WED is brain iron deficiency. Such iron deficiency in the brain is caused by complex interactions between several genetic factors and various environmental factors, including comorbidities. Iron deficiency in the brain results in dysfunction of several neurotransmitters. A decrease in adenosine activity appears first, followed by an increase in the activity of glutamate and dopamine. A decrease in adenosine activity and an increase in glutamate activity stimulate the brain arousal system, resulting in hyperarousal. In addition, overproduction of dopamine and glutamate leads to dysfunction of the cortical-striatal-thalamic circuit, resulting in symptoms such as akathisia and periodic limb movements during sleep.

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References

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