title: Sleepiness in Idiopathic REM Sleep Behavior Disorder and Parkinson Disease.
abstract: OBJECTIVE
  To determine whether patients with idiopathic and symptomatic RBD were sleepier than controls, and if sleepiness in idiopathic RBD predicted earlier conversion to Parkinson disease.
  
  
  METHODS
  The Epworth Sleepiness Scale (ESS) and its determinants were compared at the time of a video-polysomnography for an RBD diagnosis in patients with idiopathic RBD, in patients with Parkinson disease, and in controls. Whether sleepiness at time of RBD diagnosis predicted an earlier conversion to neurodegenerative diseases was retrospectively analyzed in the followed-up patients.
  
  
  RESULTS
  The 75 patients with idiopathic RBD were sleepier (ESS: 7.8 ± 4.6) at the time of RBD diagnosis than 74 age- and sex-matched controls (ESS: 5.0 ± 3.6, P < 0.0001). They reached the levels of 114 patients with Parkinson disease (ESS: 8.7 ± 4.8), whether they had (n = 78) or did not have (n = 36) concomitant RBD. The severity of sleepiness in idiopathic RBD correlated with younger age, but not with sleep measures. Among the 69 patients with idiopathic RBD who were followed up for a median 3 years (1-15 years), 16 (23.2%) developed parkinsonism (n = 6), dementia (n = 6), dementia plus parkinsonism (n = 2), and multiple system atrophy (n = 2). An ESS greater than 8 at time of RBD diagnosis predicted a shorter time to phenoconversion to parkinsonism and dementia, from RBD onset, and from RBD diagnosis (when adjusted for age and time between RBD onset and diagnosis).
  
  
  CONCLUSIONS
  Sleepiness is associated with idiopathic REM sleep behavior disorder and predicts more rapid conversion to parkinsonism and dementia, suggesting it is an early marker of neuronal loss in brainstem arousal systems.
authors.affiliation: Sorbonne Universities, UPMC Univ Paris 06, Paris, France.|Brain Research Institute (CRICM - UPMC-Paris6), Paris, France.|Sleep Disorders Unit, Pitié-Salpêtrière University Hospital, Paris, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Arnulf
authors.affiliation: Sleep Disorders Unit, Pitié-Salpêtrière University Hospital, Paris, France.
authors.forename: Dulce
authors.initials: D
authors.lastname: Neutel
authors.affiliation: Sleep Disorders Unit, Pitié-Salpêtrière University Hospital, Paris, France.
authors.forename: Bastien
authors.initials: B
authors.lastname: Herlin
authors.affiliation: Department of Biostatistics, Salpêtrière Hospital, ER4, Sorbonne Universites, UPMC Univ Paris 06, Paris, France.
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Golmard
authors.affiliation: Brain Research Institute (CRICM - UPMC-Paris6), Paris, France.|Sleep Disorders Unit, Pitié-Salpêtrière University Hospital, Paris, France.
authors.forename: Smaranda
authors.initials: S
authors.lastname: Leu-Semenescu
authors.affiliation: Sleep Disorders Unit, Pitié-Salpêtrière University Hospital, Paris, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Cochen de Cock
authors.affiliation: Sorbonne Universities, UPMC Univ Paris 06, Paris, France.|Brain Research Institute (CRICM - UPMC-Paris6), Paris, France.
authors.forename: Marie
authors.initials: M
authors.lastname: Vidailhet
mesh_terms: D000368:Aged; D001143:Arousal; D001933:Brain Stem / Q000473:pathology; D003704:Dementia / Q000150:complications; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D019578:Multiple System Atrophy / Q000150:complications; D010300:Parkinson Disease / Q000209:etiology* / Q000503:physiopathology*; D020734:Parkinsonian Disorders / Q000150:complications; D017286:Polysomnography; D020187:REM Sleep Behavior Disorder / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology*; D012189:Retrospective Studies; D012894:Sleep Stages / Q000502:physiology*; D013997:Time Factors
keywords: dementia; hypersomnolence; parkinsonism; synucleinopathy