Table 2.
Sleep variables with and without events
| Variable | Total (N = 764) | Event free (N = 354) | Incident case (N = 410) | P value |
|---|---|---|---|---|
| Apnoea–hypopnoea index, events/h | 15.5 (6.4, 29.3) | 15.2 (6.1, 29.2) | 16.1 (6.6, 29.2) | 0.856 |
| Oxygen desaturation index, events/h | 19.9 (11.4, 32.9) | 19.6 (10.2, 33.0) | 20.4 (12.0, 32.3) | 0.484 |
| T90, min | 19.5 (3.0, 83.0) | 9.0 (2.0, 59.8) | 28.0 (4.0, 94.5) | <0.001 |
| TRT90, % | 5.0 (0.6, 21.0) | 2.4 (0.4, 16.0) | 7.6 (0.9, 23.9) | <0.001 |
| Mean oxygen saturation, % | 94.0 (93.0, 96.0) | 95.0 (93.0, 96.0) | 94.0 (93.0, 96.0) | 0.004 |
| Minimal oxygen saturation, % | 79.0 (74.0, 83.0) | 80.0 (75.0, 83.0) | 79.0 (73.0, 82.0) | 0.003 |
| SDB | 0.477 | |||
| No or mild SDB, n (%) | 358 (46.9) | 166 (46.9) | 192 (46.8) | |
| Obstructive sleep apnoea, n (%) | 126 (16.5) | 64 (18.1) | 62 (15.1) | |
| Central sleep apnoea, n (%) | 280 (36.6) | 124 (35.0) | 156 (38.0) |
SDB, sleep‐disordered breathing; T90, time < 90% oxygen saturation; TRT90, proportion of total recording time < 90% oxygen saturation.