Lung function and airway responsiveness as classified by body mass index (BMI)
| Underweight (BMI <18.5) | Normal (BMI 18.5–24.9) | Overweight (BMI 25.0–29.9 ) | Moderate obesity (BMI 30.0–34.9) | Severe obesity (BMI ⩾35.0) | p value | |
|---|---|---|---|---|---|---|
| FEV1 (% pred) | 95.0 (91.9 to 98.1)3-150 | 102.0 (101.3 to 102.7) | 100.5 (99.5 to 101.5) | 99.2 (97.3 to 101.1) | 98.1 (95.2 to 101.0)3-150 | <0.001 |
| FVC (% pred) | 94.2 (91.5 to 96.9)3-150 | 99.4 (98.7 to 101.1) | 97.4 (96.4 to 98.4) | 95 (93.1 to 96.9)3-150 | 93.6 (90.7 to 96.5)3-150 | <0.001 |
| FEV1/FVC (%) | 86.4 (84.3 to 88.5) | 86.3 (85.9 to 86.7) | 85.8 (85.4 to 86.2) | 86.9 (85.9 to 87.9) | 87.6 (86.1 to 89.1) | NS |
| PEF (% pred) | 89.9 (85.7 to 94.1)3-150 | 102.2 (101.1 to 103.3) | 105.5 (104.1 to 106.9) | 106.2 (103.2 to 109.2) | 106.2 (101.8 to 110.6) | <0.001 |
| FEF25–75 (% pred) | 85.8 (79.7 to 91.9)3-150 | 97.1 (95.7 to 98.5) | 98.5 (96.5 to 100.5) | 101.4 (97.4 to 105.4) | 101.2 (94.3 to 108.1) | 0.001 |
| DRR (measure of AR) | 6.32 (4.88 to 8.18)3-150 | 4.71 (4.52 to 4.92) | 4.42 (4.23 to 4.62) | 4.72 (4.28 to 5.21) | 4.66 (4.08 to 5.33) | 0.017 |
FEV1 = forced expiratory volume in one second; FVC = forced vital capacity; PEF = peak expiratory flow; FEF25–75 = mid forced expiratory flow; DRR = dose response rate; AR = airway responsiveness.
All values are mean (95% confidence intervals).
↵3-150 Significant difference compared with normal group.