Demographic, anthropometrics and sleep disordered breathing parameters
| Entire group | Low Pcritp | High Pcritp | p-value | |
| Subjects | 14 | 7 | 7 | |
| Age years | 37.2 (34.0–43.2) | 42.3 (34.0–48.4) | 34.9 (34.0–43.2) | 0.710 |
| Anthropometrics | ||||
| Weight kg | 127.8 (122.3–134.2) | 125.9 (122.3–128.3) | 132.7 (119.6–136.9) | 0.456 |
| BMI kg·m−2 | 48.6 (45.9–50.1) | 49.1 (44.0–51.3) | 48.1 (47.6–50.1) | 1 |
| Neck circumference cm | 39.7 (36.8–41.3) | 39.8 (37.0–42.2) | 39.5 (36.0–41.3) | 0.710 |
| Waist circumference# cm | 126.8 (120.8–134.8) | 129.7 (120.8–136.5) | 126.8 (112.0–132.7) | 0.534 |
| Hip circumference# cm | 143.8 (136.5–145.8) | 140.2 (135.0–145.5) | 144.3 (141.0–148.7) | 0.628 |
| Waist/hip ratio# | 0.91 (0.86–0.94) | 0.94 (0.91–0.96) | 0.87 (0.85–0.92) | 0.138 |
| Respiratory disturbance index events·h−1 | ||||
| NREM | 3.1 (1.6–4.5) | 2.3 (0.7–4.5) | 3.3 (3.0–5.2) | 0.165 |
| REM | 10.6 (7.5–22.9) | 22.9 (2.3–43.8) | 10.5 (7.5–10.6) | 0.259 |
| Total¶ | 4.4 (2.5–6.6) | 4.2 (2.3–9.5) | 4.5 (3.9–6.5) | 1 |
| Oxygen desaturation index (4% SpO2 drop)+ events·h−1 | ||||
| NREM | 1.7 (0.63–2.23) | 1.1 (0.44–2.51) | 1.9 (1.84–1.95) | 0.291 |
| REM | 1.8 (0.63–3.46) | 2.6 (0.54–5.94) | 1.2 (0.72–1.98) | 0.291 |
| Total¶ | 3.8 (2.03–5.50) | 3.8 (0.73–7.56) | 3.8 (2.58–3.95) | 0.808 |
| Peripheral capillary oxyhaemoglobin saturation % | ||||
| Baseline SpO2 | ||||
| NREM | 96.0 (94.8–96.8) | 95.6 (94.5–96.2) | 96.6 (94.8–97.7) | 0.209 |
| REM | 95.8 (95.3–96.6) | 95.6 (95.1–95.8) | 96.5 (95.8–96.7) | 0.128 |
| Total¶ | 95.8 (95.2–96.9) | 95.7 (95.2–95.8) | 96.6 (95.1–97.1) | 0.259 |
| Average low SpO2 | ||||
| NREM | 91.6 (90.2–93.0) | 91.0 (90.2–91.6) | 92.9 (90.1–93.6) | 0.366 |
| REM | 91.3 (90.5–91.8) | 90.7 (88.8–91.3) | 91.5 (90.5–92.7) | 0.128 |
| Total¶ | 91.4 (90.1–92.7) | 90.8 (89.2–91.4) | 92.5 (90.3–93.0) | 0.209 |
| Pcritp cmH2O | −1.98 (−5.22–−1.00) | −5.22 (−8.00–−3.01) | −1.00 (−1.55–1.30) | 0.001 |
Data are presented as n or median (interquartile range), unless otherwise stated. Pcritp: passive critical pressure; BMI: body mass index; NREM: non-rapid eye movement (REM); SpO2: peripheral capillary oxyhaemoglobin saturation. #: one patient had no waist and hip measurements; ¶: NREM and REM values combined; +: oxygen desaturation indices could not be calculated in two patients.