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Periodic Limb Movements in Sleep Increase with Age

Clin Neurophysiol; 2018 Nov; Leary, Moore IV, et al

A significant number of adults have periodic limb movements in sleep (PLMS) and prevalence increased with age, a recent study found. However, there was no noteworthy association between prevalence of periodic limb movement index (PLMI) category and sleepiness unless stratified by restless leg syndrome (RLS) symptoms. Researchers identified limb movements in 2,335 Wisconsin Sleep Cohort polysomnograms collected over 12 years. PLMI ≥15 was calculated at baseline (n=1,084). McNemar's test assessed changes in prevalence over time. They found:

  • Prevalence of PLMI ≥15 at baseline was 25.3%.
  • Longitudinal prevalence increased significantly with age.
  • Sleepiness did not differ significantly between PLMI groups unless stratified by RLS symptoms.
  • The RLS+/PLM+ group was sleepier than the RLS+/PLM− group.
  • Multiple Sleep Latency Test trended towards increased alertness in the RLS−/PLM+ group compared to RLS−/PLM−.
  • Results indicate that RLS and PLMS may have distinct clinical consequences and interactions that can help guide treatment approach.


Leary EB, Moore IV HE, Schneider LD, Finn LA, Peppard PE, Mignot E. Periodic limb movements in sleep: Prevalence and associated sleepiness in the Wisconsin Sleep Cohort. Clin Neurophysiol. 2018;129(11):2306-2314. doi:10.1016/j.clinph.2018.08.022.