Table 2. Diagnostic polysomnography characteristics in groups with different ΔP values.
| Total (n=50) | Prequal (n=9) | APAP90+ (n=18) | CPAPmanual+ (n=23) | p | |
|---|---|---|---|---|---|
| Total sleep time, min | 318.5±77.3 | 285.5±42.2 | 323.0±93.3 | 327.0±93.4 | 0.368 |
| Sleep latency, min | 11.9±12.9 | 10.4±6.7 | 12.1±16.6 | 12.4±11.8 | 0.929 |
| REM latency, min | 126.4±77.6 | 123.1±90.5 | 142.2±86.8 | 115.3±65.4 | 0.550 |
| Sleep efficiency, % | 74.4±16.2 | 72.6±11.4 | 73.6±13.9 | 75.8±19.6 | 0.850 |
| NREM sleep, % | 84.9±7.9 | 87.1±6.6 | 86.4±5.3 | 82.8±9.6 | 0.214 |
| REM sleep, % | 15.1±7.9 | 12.9±6.6 | 13.6±5.3 | 17.2±9.6 | 0.214 |
| WASO, hr | 86.4±51.4 | 99.4±41.6 | 93.7±53.1 | 75.6±53.3 | 0.384 |
| Supine sleep, % | 60.9±25.1 | 52.5±27.2 | 58.7±26.3 | 65.8±23.2 | 0.367 |
| Not-supine sleep, % | 39.1±25.1 | 47.5±27.2 | 41.3±26.3 | 34.2±23.2 | 0.367 |
| Arousal index, events/hr | |||||
| Total | 60.1±32.8 | 64.0±28.2 | 65.6±23.9 | 54.4±40.0 | 0.524 |
| Related to respiration | 49.3±31.7 | 47.1±27.6 | 59.3±26.1 | 42.3±36.1 | 0.234 |
| Related to PLM | 0.8±3.6 | 1.6±3.6 | 0.9±3.6 | 0.5±1.2 | 0.558 |
| Spontaneous | 10.0±8.8 | 15.3±10.2 | 5.4±3.8 | 11.6±9.7 | 0.010* |
| AHI, events/hr | 56.7±27.7 | 56.0±23.3 | 67.4±25.0 | 48.7±29.5 | 0.100 |
| Apnea, events/hr | 23.4±28.1 | 20.7±25.5 | 30.6±24.2 | 19.1±31.6 | 0.409 |
| Hypopnea, events/hr | 33.3±15.1 | 35.2±11.6 | 36.8±21.0 | 29.8±9.8 | 0.314 |
| Ratio of AHI | |||||
| REM/NREM sleep | 1.0±0.8 | 1.3±1.4 | 0.9±0.6 | 1.0±0.7 | 0.589 |
| Supine/not supine | 12.5±29.6 | 15.2±32.3 | 7.6±23.1 | 15.3±336 | 0.688 |
| PLM index, events/hr | 4.0±10.6 | 7.2±14.0 | 2.7±11.2 | 3.7±8.9 | 0.582 |
| Oxygen saturation | |||||
| Overall, % | 92.7±5.1 | 94.5±1.8 | 94.5±3.6 | 92.4±6.7 | 0.542 |
| Minimum, % | 77.8±12.2 | 83.1±5.4 | 72.3±10.0 | 80.1±14.3 | 0.042* |
| ODI, events/hr | 34.8±24.5 | 27.8±18.1 | 44.8±22.9 | 29.4±26.0 | 0.090 |
| Sat. <90%, min | 18.0±23.1 | 7.4±10.3 | 24.3±23.5 | 16.8±25.1 | 0.217 |
Data are mean±SD values.
*p<0.05.
AHI: apnea hypopnea index, APAP90+: average device pressure ≤90% of the time higher than optimal pressure obtained by manual continuous positive airway pressure titration, CPAPmanual+: optimal pressure obtained by manual continuous positive airway pressure titration higher than average device pressure ≤90% of the time (ΔP ≤-1), NREM: non-REM, ODI: oxygen desaturation index, PLM: periodic limb movement, Prequal: same pressure, REM: rapid eye movement, Sat: <90%, time during which oxygen saturation was <90%, WASO: wake after sleep onset, ΔP: pressure difference.