Table 2. Results of sleep study before and after CPAP treatment.
| Variables | Control (n=20) | OSA group (n=40) | |
|---|---|---|---|
| Before CPAP | After CPAP | ||
| AHI, times/hour | 3.7±1.2 | 55.7±16.5* | 3.7±2.5 |
| ODI, times/hour | 2.8±1.2 | 49.5±15.8* | 2.7±2.0 |
| Baseline SaO2, % | 98.2±0.8 | 97.0±0.9* | 97.9±0.7 |
| Minimum SaO2, % | 90.7±1.9 | 73.1±8.0* | 90.9±2.0 |
| Sleep architecture, % | |||
| Stage 1 | 13.5±4.1 | 28.2±7.1* | 16±3.1 |
| Stage 2 | 50.2±4.3 | 50.8±6.3 | 49.3±3.9 |
| Stage 3 | 18.0±3.0 | 10.2±3.4* | 17.1±3.3 |
| REM | 18.3±4.0 | 10.8±3.6* | 17.6±3.2 |
| TST, min | 420.9±34.9 | 397.4±38.1 | 415.1±33.6 |
| Sleep efficiency, % | 85.9±6.3 | 76.4±6.7* | 88.7±4.0 |
| AI, times/hour | 5.1±0.8 | 59.5±22.0* | 4.1±3.7 |
Student’s t-test was applied for comparison between control and OSA group before CPAP and paired t-test was used for comparison between before and after CPAP treatment within OSA group. *, P<0.05, for difference before and after CPAP. CPAP, continuous positive airway pressure; OSA, obstructive sleep apnea; AHI, apnea-hypopnea index; ODI, oxygen desaturation index; SaO2, arterial oxyhemoglobin saturation; REM, rapid eye movement; TST, total sleep time; AI, arousal index.