Periodic limb movement disorder

Periodic limb movement disorder (PLMD) is characterized by periodic limb movements of sleep (PLMS). These repetitive limb movements (mostly of the legs) occur mainly during non-rapid eye movement (non-REM) sleep and involve dorsiflexion of the toes and ankles and occasionally flexion of the hip and knee.

PLMD is diagnosed when the periodic limb movement of sleep index (PLMS-I; the number of periodic limb movements per hour of sleep) is >15 and results in clinically significant sleep disturbance or daytime impairment. The diagnosis is confirmed by polysomnography, and other causes of sleep-wake disturbance must be excluded.

May be either primary (idiopathic) or associated with conditions such as restless legs syndrome, obstructive sleep apnea syndrome, REM sleep behavior disorder, narcolepsy, congestive heart failure, essential hypertension, end-stage renal disease, spinal cord injury, syringomyelia, alcohol dependence, Parkinson disease, and Tourette syndrome.

May be related to intake of medications including lithium, tricyclic antidepressants, and selective serotonin-reuptake inhibitors.

Evidence from randomized controlled trials for the treatment of primary PLMD is lacking. Reassurance and lifestyle measures are sufficient for many patients. PLMD associated with other conditions is managed by treating the underlying cause and the cessation any causative drugs.

Periodic limb movements of sleep (PLMS) are characterized as repetitive limb movements (mostly of the legs) arising mainly during non-rapid eye movement sleep.[1]American Academy of Sleep Medicine. The AASM international classification of sleep disorders - third edition, text revision (ICSD-3-TR). 2023 [internet publication]. https://aasm.org/clinical-resources/international-classification-sleep-disorders ​​[2]Garcia-Borreguero D, Ferini-Strambi L, Kohnen R, et al. European guidelines on management of restless legs syndrome: report of a joint task force by the European Federation of Neurological Societies, the European Neurological Society and the European Sleep Research Society. Eur J Neurol. 2012;19:1385-1396. http://www.ncbi.nlm.nih.gov/pubmed/22937989?tool=bestpractice.com [3]Ferri R, Fulda S, Allen RP, et al. World Association of Sleep Medicine (WASM) 2016 standards for recording and scoring leg movements in polysomnograms developed by a joint task force from the International and the European Restless Legs Syndrome Study Groups (IRLSSG and EURLSSG). Sleep Med. 2016 Oct;26:86-95. http://www.ncbi.nlm.nih.gov/pubmed/27890390?tool=bestpractice.com ​​​​​[4]Hornyak M, Feige B, Reimann D, et al. Periodic leg movements in sleep and periodic limb movement disorder: prevalence, clinical significance and treatment. Sleep Med Rev. 2006;10:169-177. http://www.ncbi.nlm.nih.gov/pubmed/16762807?tool=bestpractice.com [5]Aurora RN, Kristo DA, Bista SR, et al. The treatment of restless legs syndrome and periodic limb movement disorder in adults-an update for 2012: practice parameters with an evidence-based systematic review and meta-analyses: an American Academy of Sleep Medicine Clinical Practice Guideline. Sleep. 2012 Aug 1;35(8):1039-62. http://www.aasmnet.org/Resources/PracticeParameters/TreatmentRLS.pdf http://www.ncbi.nlm.nih.gov/pubmed/22851801?tool=bestpractice.com ​​​ Periodic limb movement disorder (PLMD) is diagnosed when the frequency of PLMS is >15/hour in adults, and the PLMS cause clinically significant sleep disturbance or daytime impairment.[1]American Academy of Sleep Medicine. The AASM international classification of sleep disorders - third edition, text revision (ICSD-3-TR). 2023 [internet publication]. https://aasm.org/clinical-resources/international-classification-sleep-disorders This topic focuses on the diagnosis and management of PLMD in adults.