Comparison of polysomnography parameters for healthy children tested at low and high altitude
| Vézina et al. [24] | Ucros et al. [1] | |
| Altitude MASL | 645 | 2560 |
| Patients n | 562 | 32 |
| Age years | 1 | 4–7 |
| Average SpO2 % | 97.1 (10th centile 95.5) | 93 (5th centile 90.5) |
| SpO2 nadir % | 87.0 (10th centile 81.0) | 84 (5th centile 56.6) |
| ODI3 events·h−1 | 6.7 (90th centile 15.8) | 11.2 (95th centile 15.2) |
| Obstructive apnoea index events·h−1 | 0 (90th centile 0.5) | |
| Obstructive AHI events·h−1 | 8.8 (95th centile 21.2) | |
| Central apnoea index events·h−1 | 2.5 (90th centile 7.1)# | |
| Central AHI events·h−1 | 0.4 (95th centile 2.4) | |
| Hypopnoea index events·h−1 | 1.2 (90th centile 3.5) | |
| Total AHI events·h−1 | 4.2 (90th centile 10.7) | 9.2 (95th centile 17.9) |
Data are presented as medians with indicated centiles, unless otherwise stated. MASL: metres above sea level; SpO2: peripheral oxygen saturation; ODI3: 3% oxygen desaturation index; AHI: apnoea–hypopnoea index. #: this high central event rate in the lower altitude group is likely to be due to younger age.