Subject characteristics and comparison by sex and menopausal status
| Total | Comparison by sex | Comparison by menopausal status in females | |||||
| Females | Males | p-value | Non-menopausal | Menopausal | p-value | ||
| Age yrs | 43.1±12.9 | 43.7±13.1 | 42.1±12.4 | 0.256 | 35.53±9.71 | 57.18±6.25 | <0.001 |
| Smoking | 0.044 | 0.043 | |||||
| Current | 94 (26) | 59 (25.8) | 35 (26.5) | 43 (33.1) | 12 (16.7) | ||
| Former | 103 (28.5) | 56 (24.5) | 47 (35.6) | 29 (22.3) | 20 (27.8) | ||
| Never | 164 (45.4) | 114 (49.8) | 50 (37.9) | 58 (44.6) | 40 (55.6) | ||
| BMI kg·m−2 | 43.0±6.86 | 43.0±7.0 | 42.91±6.6 | 0.890 | 43.33±6.83 | 42.43±7.52 | 0.276 |
| Waist–hip ratio | 0.94±0.09 | 0.904±0.08 | 1.002±0.08 | <0.001 | 0.88±0.07 | 0.94±0.07 | <0.001 |
| Waist cm | 122±14 | 117±13 | 129±13 | <0.001 | 116.8±13 | 119.72±12 | 0.093 |
| Body fat % | 48.9±7.2 | 52.2±4.9 | 42.9±6.8 | <0.001 | 52.18±4.93 | 52.64±4.29 | 0.638 |
| Leptin μg·L−1 | 54.5±30.2 | 65.4±29.3 | 36.0±21.4 | <0.001 | 64.91±30.13 | 64.64±28.96 | 0.993 |
| Log leptin μg·L−1 | 1.666±0.259 | 1.769±0.212 | 1.491±0.238 | <0.001 | 1.76±0.22 | 1.76±0.21 | 0.993 |
| Log leptin/fat % | 3.487±0.490 | 3.408±0.434 | 3.506±0.553 | 0.159 | 3.39±0.44 | 3.39±0.39 | 0.926 |
| TLC % pred | 88.93±11.66 | 92.19±10.56 | 83.32±11.39 | <0.001 | 92.50±10.71 | 91.56±10.54 | 0.578 |
| Baseline P0.1 cmH2O | 4.51±1.87 | 4.385±1.833 | 4.738±1.921 | 0.084 | 4.49±1.68 | 3.82±1.35 | <0.001 |
| Baseline PET,CO2 mmHg | 33.32±5.75 | 32.97±5.743 | 33.93±5.72 | 0.126 | 32.51±5.34 | 34.27±5.77 | 0.025 |
| P0.1/(VT/tI) cmH2O·L−1·s−1 | 7.735±3.020 | 7.850±2.885 | 7.536±3.242 | 0.086 | 8.00±2.68 | 7.05±2.53 | 0.007 |
| P0.1/PET,CO2 cmH2O/mmHg | 1.01±0.90 | 0.87±0.84 | 1.27±0.94 | <0.001 | 0.90±0.88 | 0.82±0.75 | 0.776 |
| V′E/PET,CO2 L·min−1/mmHg | 2.61±1.87 | 2.07±1.27 | 3.60±2.34 | <0.001 | 2.15±1.28 | 1.92±1.29 | 0.251 |
| AHI h−1 | 22.05±25.35 | 15.53±18.21 | 34.21±31.64 | <0.001 | 13.79±18.54 | 20.05±18.76 | 0.002 |
| Minimal Sp,O2 % | 80.55±11.17 | 82.13±10.64 | 77.63±11.56 | 0.001 | 84.4±10.31 | 78.63±10.78 | <0.001 |
| Mean Sp,O2 % | 94.50±2.83 | 94.83±2.61 | 93.92±3.12 | 0.016 | 95.46±2.45 | 93.69±2.81 | <0.001 |
Variables are shown as mean±sd and categorical variables as absolute count n (%). BMI: body mass index; TLC: total lung capacity; % pred: % predicted; P0.1: mouth occlusion pressure; PET,CO2: end-tidal carbon dioxide tension; VT: tidal volume; tI: time taken for inspiration; V′E: minute ventilation; AHI: apnoea/hypopnoea index; Sp,O2: arterial oxygen saturation. 1 mmHg = 0.133 kPa.