title: While Isolated Periodic Limb Movement Disorder Significantly Impacts Sleep Depth and Efficiency, Co-Morbid Restless Leg Syndrome Mainly Exacerbates Perceived Sleep Quality.
abstract: Restless leg syndrome (RLS) and periodic limb movement (PLM) disorder (PLMD) can affect sleep quality and interfere with daytime functioning. Whether the co-morbidity of RLS further worsens daytime symptoms, sleep architecture and quality in patients with PLMs, is not yet fully clarified.
  
  
  
  Sleep (polysomnography) and daytime symptoms of 47 drug-free patients, assigned to isolated PLMD or co-morbid RLS subgroups, were compared to controls in a retrospective cohort-study (n = 501). Associations between perceived sleep quality, fatigue, sleepiness, mood and sleep variables were explored descriptively.
  
  
  
  Although co-morbid patients showed worsened sleep quality, both patient groups showed similar sleepiness and affective symptoms. While significantly differing from controls, patients presented similarly increased light sleep, decreased slow-wave sleep and lowered sleep efficiency. Altered sleep quality, fatigue and sleepiness were significantly correlated to decreased slow-wave sleep and sleep fragmentation. Affective symptoms, fatigue and perceived sleep quality also correlated to PLM index.
  
  
  
  Sleep structure and efficiency were similarly impacted in isolated PLMD and in co-morbid RLS. RLS mainly worsened perceived sleep quality. Given that systematic treatment for isolated PLMD is currently not recommended, such results may question whether no or different-from-RLS treatment strategies are compatible with optimal care.
authors.affiliation: Sleep Laboratory and Unit for Chronobiology U78, Brugmann University Hospital, Université Libre de Bruxelles (ULB), Brussels, Belgium.
authors.forename: Florent-Xavier
authors.initials: FX
authors.lastname: Hardy De Buisseret
authors.forename: Olivier
authors.initials: O
authors.lastname: Mairesse
authors.forename: Johan
authors.initials: J
authors.lastname: Newell
authors.forename: Paul
authors.initials: P
authors.lastname: Verbanck
authors.forename: Daniel
authors.initials: D
authors.lastname: Neu
mesh_terms: D000328:Adult; D000368:Aged; D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020189:Nocturnal Myoclonus Syndrome / Q000453:epidemiology*; D017286:Polysomnography / Q000379:methods; D012148:Restless Legs Syndrome / Q000453:epidemiology*; D012189:Retrospective Studies; D012890:Sleep / Q000502:physiology*
keywords: Fatigue; Perceived sleep quality; Periodic limb movements; Polysomnography; Restless leg syndrome; Sleepiness