Table 2.
Polysomnography Parameters
| Variables | COPD+OSA (n = 29) | COPD (n=36) | p-value |
|---|---|---|---|
| TST, min | 318±72 | 339±83 | 0.29 |
| Sleep efficiency, % | 72.1±13.5 | 68.9±11.9 | 0.31 |
| Arousal index, events/h | 30.1±14.6 | 20.0±10.4 | <0.01 |
| Sleep architecture, % TST | |||
| Stage N1 | 16.3±9.8 | 14.4±9.2 | 0.42 |
| Stage N2 | 57.2±13.2 | 54.9±14.1 | 0.50 |
| Stage N3 | 10.5±8.3 | 13.9±11.6 | 0.19 |
| Stage R | 15.9±11.3 | 16.8±11.9 | 0.76 |
| AHI, events/h | 29.3±11.4 | 7.6±4.1 | <0.01 |
| AI, events/h | 5.2±7.1 | 4.6±6.9 | 0.73 |
| HI, events/h | 24.1±12.0 | 3.0±4.4 | <0.01 |
| Mean SpO2, % | 92.9±3.1 | 93.6±2.6 | 0.42 |
| Lowest SpO2, % | 78.9±7.9 | 85.0±6.1 | <0.01 |
| TST90 (%) | 17.3±15.7 | 7.8±14.6 | 0.01 |
| ODI (≥3%), events/h | 20.8±11.5 | 5.6±5.0 | <0.01 |
Note: Data are expressed as mean ± standard deviation.
Abbreviations: OSA, obstructive sleep apnea; AHI, apnoea hypopnoea index; AI, apnea index; HI, hypopnea index; SpO2, pulse oxygen saturation; TST, total sleep time; R, rapid eye movement; ODI, oxygen desaturation index with oximetry recording; TST90, percentage of total sleep time spent with oxyhemoglobin saturation below 90%.