Table 2

Changes from baseline in real CPAP and sham CPAP groups and the between-group differences

Mean changeBetween-group differences (real – sham)p Value
Real CPAP (n=26)Sham CPAP (n=24)Mean difference (95% CI)
Sleep architecture and sleepiness
 TST (min)25.226.9−1.7 (−43.2 to 39.9)0.94
 Sleep efficiency (% TST)4.82.82.0 (−5.9 to 9.8)0.62
 REM (% TST)0.04−0.020.06 (0.01 to 0.1) 0.02
 Non-REM (% TST)−0.040.02−0.06 (−0.1 to −0.01) 0.02
 SWS (% TST)11.64.57.1 (−0.04 to 14.3)0.05
 Subjective sleepiness (ESS, scale 0–18)−1.8−1.7−0.1 (−1.6 to 1.9)0.87
 Objective sleepiness (OSLER, min)4.53.21.3 (−2.6 to 5.3)0.19
Anthropometry
 BMI (kg/h2)0.140.080.06 (−0.3 to 0.4)0.71
 Weight (kg)0.50.30.3 (−0.7 to 1.2)0.57
 Waist circumference (cm)−0.5−0.70.2 (−1.2 to 1.6)0.79
Clinic blood pressure
 SBP (mm Hg)−4.75−0.50−4.25 (−9.60 to 1.10)0.12
 DBP (mm Hg)0.41−0.040.45 (−3.38 to 4.28)0.82
 HR (beats/min)−1.481.38−2.86 (−7.17 to 1.45)0.19
 MAP (mm Hg)−1.32−0.30−1.01 (−4.49 to 2.47)0.56
  • Bold values are statistically significant (p<0.05).

  • Data are mean differences from baseline, between-group differences (and 95% CIs) and unadjusted p values. Between-group differences were determined by linear regression. Mixed model analysis was used for outcomes with repeated measures.

  • BMI, body mass index; CPAP, continuous positive airway pressure; DBP, diastolic blood pressure; ESS, Epworth Sleepiness Scale; HR, heart rate; MAP, mean arterial pressure; OSLER, the Oxford sleep resistance test; REM, rapid eye movement; SBP, systolic blood pressure; SWS, slow wave sleep; TST, total sleep time.