title: Sleep-disordered breathing and daytime postural stability.
abstract: Postural stability depends on the coordination of the central nervous system with visual sense, proprioceptive and vestibular information. Sleep deprivation has been shown to affect this function. The objective of our study was to assess the effects of sleep-disordered breathing (SDB) on postural stability.
  
  
  
  158 subjects referred for suspected SDB had an overnight sleep study and were placed on a posturographic platform in late afternoon. This platform allows measuring the centre of pressure (CoP) oscillations and to calculate: total displacement of CoP in X and Y axes, mean speed of CoP displacement and the length as function of surface (LFS) ratio (length of CoP displacement/surface of CoP trajectory).
  
  
  
  98 men and 60 women were included. Mean age±SD was 45.4±5.5 years old, body mass index (BMI) 27.5±5.6 kg/m(2) and apnoea-hypopnoea index (AHI) 13.6±16.1/h. AHI was <5/h in 64 (41%) subjects, 5-15/h in 43 (27%), 15-30/h in 30 (19%) and >30/h in 21 (13%). In patients with an AHI >5/h versus AHI <5/h, we observed an important increase in LFS (+21%, p<0.001), in XY length (+23%, p<0.001) and in mean speed (+23%, p<0.001). After controlling for age, BMI and sleepiness (Epworth) in multivariate regression models, there was a positive association between all nocturnal breathing parameters (specifically: mean SpO2, AHI, oxygen desaturation index 3% and % time with SpO2 <90%) and the main stability outcomes (all p<0.05).
  
  
  
  SDB severity, especially the mean nocturnal SpO2 level, is associated with impaired daytime postural stability.
authors.affiliation: Department of Health Research, University of Health Sciences, University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland Department of Physiology, GRISSUL (Group of Research of Institute of Sports Sciences), University of Lausanne, Lausanne, Switzerland.
authors.forename: Francis
authors.initials: F
authors.lastname: Degache
authors.affiliation: Department of Physiology, Faculty of Biology and Medicine, Institute of Sports Sciences, University of Lausanne, Lausanne, Switzerland.
authors.forename: Yannick
authors.initials: Y
authors.lastname: Goy
authors.affiliation: Center for Investigation and Research in Sleep (CIRS), University Hospital of Lausanne (CHUV), Lausanne, Switzerland Pulmonary Medicine Department, University Hospital of Montreal (CHUM), Montreal, Canada.
authors.forename: Sopharat
authors.initials: S
authors.lastname: Vat
authors.affiliation: Center for Investigation and Research in Sleep (CIRS), University Hospital of Lausanne (CHUV), Lausanne, Switzerland.
authors.forename: José
authors.initials: J
authors.lastname: Haba Rubio
authors.affiliation: Department of Health Research, University of Health Sciences, University of Applied Sciences and Arts Western Switzerland, Lausanne, Switzerland.
authors.forename: Olivier
authors.initials: O
authors.lastname: Contal
authors.affiliation: Center for Investigation and Research in Sleep (CIRS), University Hospital of Lausanne (CHUV), Lausanne, Switzerland.
authors.forename: Raphaël
authors.initials: R
authors.lastname: Heinzer
mesh_terms: D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D017286:Polysomnography; D004856:Postural Balance / Q000502:physiology*; D012307:Risk Factors; D012720:Severity of Illness Index; D012891:Sleep Apnea Syndromes / Q000150:complications* / Q000503:physiopathology*
chemical_list: D010100:Oxygen
keywords: Sleep apnoea