Polysomnography data
| SDB | NoSDB | p-value | |
| Patients n | 22 | 17 | |
| Characteristic | |||
| AHI events·h−1 | 22.3 (16.6–100) | 3.7 (0–12.3) | <0.001 |
| Obstructive Index events·h−1 | 6.4 (0.2–93.2) | 0.8 (0.0–7.7) | <0.001 |
| Central Index events·h−1 | 3.4 (0.0–16.5) | 0.2 (0.0–6.2) | <0.01 |
| Mixed Index events·h−1 | 0.6 (0.0–9.4) | 0.0 (0.0–1.3) | <0.001 |
| Hypopnoea Index events·h−1 | 11.8 (0.0–29.6) | 1.6 (0.0–8.7) | <0.001 |
| Desaturation Index events >4%·h−1) | 6.5 (0.0–45.0) | 1.0 (0.0–17.0) | <0.01 |
| Minimum O2 value %# | 85 (47–92) | 89 (47–96) | 0.02 |
| Total sleep time h | 5.1±1.1 | 5.5±1.3 | 0.24 |
| SL min | 17±6−88 | 11±1−38 | 0.03 |
| SE TIB asleep % | 62.6±10.9 | 72.2±12.2 | 0.01 |
| Arousal Index events·h−1 | 40.7 (13.9–117.9) | 19.4( 5.3–49.8) | <0.001 |
| Stage of sleep % | |||
| 1 | 39±16 | 30±14 | 0.07 |
| 2 | 34±12 | 40±11 | 0.10 |
| 3 and 4 | 11±7 | 11±7 | 0.86 |
| REM | 16±8 | 18±8 | 0.46 |
Data presented as mean±sd and median (range), unless otherwise stated. SDB: sleep-disordered breathing; NoSDB: no SDB; AHI: apnoea/hypopnoea index; SL: sleep latency; SE: sleep efficiency; TIB: time in bed; REM: rapid eye movement. #: note that the minimum oxygen desaturation value was 47% in both groups. This was due to isolated obstructive apnoeas with significant desaturation in one NoSDB patient. Congestive heart failure patients with SDB regularly desaturated to low levels.