title: Effect of continuous positive airway pressure versus supplemental oxygen on sleep quality in obstructive sleep apnea: a placebo-CPAP-controlled study.
abstract: OBJECTIVE
  We investigated the short-term effectiveness of continuous positive airway pressure (CPAP) and oxygen in improving sleep quality in patients with obstructive sleep apnea (OSA).
  
  
  METHODS
  Randomized, double-blind, placebo-controlled, parallel study.
  
  
  METHODS
  General Clinical Research Center at a university hospital.
  
  
  METHODS
  Seventy-six patients with untreated OSA.
  
  
  METHODS
  Patients were randomly assigned to 1 of 3 treatments (CPAP, placebo-CPAP, or nocturnal oxygen at 3 L per minute) for 2 weeks. Sleep quality was assessed at baseline and after 1 and 14 days of therapy. Repeated-measures analysis of variance was used to evaluate treatment and time effects, and their interaction.
  
  
  RESULTS
  Sixty-three patients completed the protocol. When compared with placebo-CPAP and nocturnal oxygen, CPAP increased rapid eye movement (REM) sleep and significantly reduced stage 1 sleep and the number of stage shifts (p < or = .003). CPAP improved, to within normal limits, the apnea-hypopnea index, total arousal index, and mean oxyhemoglobin saturation (p < or = .001). The effects of CPAP were apparent during the first night of therapy. Oxygen improved only mean nocturnal saturation (p = .009). CPAP had no significant effect on stage 2 sleep or slow-wave sleep.
  
  
  CONCLUSIONS
  CPAP was associated with an improvement in sleep quality in patients with OSA by consolidating sleep, reducing stage 1 sleep, and improving REM sleep. CPAP was effective in correcting the respiratory and arousal abnormalities of OSA. The effectiveness of supplemental oxygen was limited to oxyhemoglobin desaturation.
authors: Department of Medicine, University of California, San Diego, CA 92103-0804, USA. jloredo@ucsd.edu
authors: José S
authors: JS
authors: Loredo
authors: Sonia
authors: S
authors: Ancoli-Israel
authors: Eui-Joong
authors: EJ
authors: Kim
authors: Weon Jeong
authors: WJ
authors: Lim
authors: Joel E
authors: JE
authors: Dimsdale