Table 2.
Polysomnographic features of patients with REM-related OSA and non-stage specific OSA.
| Variables | Total (n = 408) |
REM-related OSA (n = 88) |
Non-stage specific OSA (n = 320) |
p-value |
|---|---|---|---|---|
| Sleep efficiency (%) | 78.9 (66.2, 87.0) | 83.7 (73.1, 89.9) | 77.9 (63.9, 86.2) | < 0.001 |
| Stage N1 (%) | 16.0 (11.0, 25.0) | 11.8 (6.7, 14.0) | 18.0 (12.0, 27.0) | < 0.001 |
| Stage N2 (%) | 49.6 ± 11.7 | 51.4 ± 11.8 | 49.1 ± 11.2 | 0.110 |
| Stage N3 (%) | 16.0 (6.7, 25.0) | 20.3 (11.5, 29.7) | 15.3 (5.8, 23.9) | < 0.001 |
| Stage REM duration (min) | 27.5 (17.0, 48.5) | 43 (22.0, 70.5) | 26 (17.0, 41.5) | < 0.001 |
| Stage REM (%) | 14.3 ± 5.6 | 15.4 ± 5.8 | 14.0 ± 5.5 | 0.047 |
| AHI (events/h) | 29.2 (14.7, 54.0) | 11.3 (7.9, 15.7) | 39.9 (22.7, 63.5) | < 0.001 |
| PSG severity | < 0.001 | |||
| Mild | 103 (25.3) | 62 (70.4) | 41 (12.8) | |
| Moderate | 107 (26.2) | 26 (29.6) | 81 (25.3) | |
| Severe | 198 (48.5) | 0 (0.0) | 198 (61.9) | |
| REM-AHI (events/h) | 45.4 (22.6, 65.1) | 37.6 (24.7, 54.6) | 49.1 (19.9, 67.9) | 0.029 |
| NREM-AHI (events/h) | 27.3 (12.0, 53.4) | 7.1 (4.4, 10.8) | 36.7 (20.7, 61.9) | < 0.001 |
| Apnea index (events/h) | 2.1 (0.2, 9.9) | 0.3 (0, 1.6) | 3.5 (0.4, 16.7) | < 0.001 |
| Hypopnea index (events/h) | 20.3 (10.5, 35.6) | 9.9 (6.8, 13.7) | 26.1 (16.1, 39.7) | < 0.001 |
| Arousal index (events/h) | 24.6 (13.9, 40.5) | 10.5 (5.8, 14.9) | 29.5 (18.1, 47.0) | < 0.001 |
| Mean SpO2 (%) | 95.0 (92.0, 96.0) | 96.0 (94.0, 97.0) | 94.0 (91.0, 96.0) | < 0.001 |
| Lowest SpO2 (%) | 83.0 (72.5, 89.0) | 86.0 (79.0, 89.0) | 82.5 (69.0, 89.0) | 0.002 |
| SpO2 time < 90% (min) | 3.0 (0.3, 12.6) | 0.9 (0.2, 3.8) | 4.3 (0.4, 18.0) | < 0.001 |
Data are expressed as mean ± SD, median (IQR), or n (%).
REM rapid eye movement, NREM non-rapid eye movement, OSA obstructive sleep apnea, AHI apnea–hypopnea index, SpO2 arterial oxygen saturation.