title: Bound to supine sleep: Parkinson's disease and the impact of nocturnal immobility.
abstract: BACKGROUND
  Impaired nocturnal mobility is a well-known problem in Parkinson's disease (PD), and clinical experience suggests a predominance of supine body position during sleep. However, this assumption - and potential consequences - still awaits objective validation by a polysomnography-based and adequately controlled study.
  
  
  METHODS
  Clinical and polysomnographical analysis of 80 consecutive PD patients and 80 control subjects carefully matched for age, sex, body mass index and apnea-hypopnea index.
  
  
  RESULTS
  PD patients slept twice as much in supine position than control subjects (62.2 ± 32.9% vs. 34.2 ± 28.5%, p < 0.001). In PD, but not in control subjects, more supine sleep correlated with fewer changes in body position (rho = -0.434, p < 0.001). Longer PD disease duration was an independent predictor of more supine sleep in multiple linear regression analysis (β = 0.389, p < 0.001); conversely, more supine sleep was associated with higher apnea-hypopnea index and daytime sleepiness.
  
  
  CONCLUSIONS
  We confirmed that supine sleep is common in PD, and increases with longer disease duration. Our findings indicate that supine sleep may contribute to the overall disease burden by deteriorating sleep-disordered breathing and daytime vigilance.
authors: Department of Neurology, University Hospital Zurich, Switzerland.
authors: Michael
authors: M
authors: Sommerauer
authors: Department of Neurology, University Hospital Zurich, Switzerland.
authors: Esther
authors: E
authors: Werth
authors: Department of Neurology, University Hospital Zurich, Switzerland.
authors: Rositsa
authors: R
authors: Poryazova
authors: Department of Neurology, University Hospital Zurich, Switzerland; Department of General Pathology and Pathological Physiology, Institute of Experimental Medicine, St. Petersburg, Russia.
authors: Yury V
authors: YV
authors: Gavrilov
authors: Department of Neurology, University Hospital Zurich, Switzerland.
authors: Sabrina
authors: S
authors: Hauser
authors: Department of Neurology, University Hospital Zurich, Switzerland. Electronic address: philipp.valko@usz.ch.
authors: Philipp O
authors: PO
authors: Valko
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D010300:Parkinson Disease / Q000150:complications*; D017286:Polysomnography; D012189:Retrospective Studies; D012890:Sleep / Q000502:physiology*; D016683:Supine Position
keywords: Nocturnal immobility; Parkinson's disease; Sleep position; Sleep-disordered breathing; Sleepiness; Supine