Table 4. Associations of wheezing phenotype with lung function in 4448 children with complete data on wheezing and lung function measurements at 8–9 years and 2957 with airway responsiveness measurements at 8–9 years.
| Phenotype | FEV1 (l) | FEF25–75 (l/s) | Airway responsiveness* | ||||||
| Total | Mean (SD) | Mean difference (95% CI) | Total | Mean (SD) | Mean difference (95% CI) | Total | Mean (SD) | Mean difference (95% CI) | |
| Transient early | 724 | −0.16 (0.91) | −0.29 (−0.37 to −0.21) | 735 | −0.12 (0.96) | −0.31 (−0.39 to −0.24) | 481 | 0.03 (1.5) | 0.29 (0.13 to 0.44) |
| Prolonged early | 396 | −0.17 (1.11) | −0.30 (−0.41 to −0.20) | 402 | −0.34 (0.95) | −0.54 (−0.64 to −0.44) | 263 | 0.01 (1.5) | 0.27 (0.07 to 0.47) |
| Intermediate | 118 | −0.4 (1.18) | −0.53 (−0.71 to −0.35) | 120 | −0.49 (1.17) | −0.69 (−0.87 to −0.51) | 79 | 1.51 (1.7) | 1.76 (1.41 to 2.12) |
| Late | 265 | −0.08 (0.98) | −0.21 (−0.33 to −0.08) | 269 | −0.21 (1.07) | −0.40 (−0.53 to −0.28) | 176 | 1.36 (1.7) | 1.61 (1.37 to 1.85) |
| Persistent | 306 | −0.27 (1.05) | −0.40 (−0.52 to −0.28) | 310 | −0.49 (1.12) | −0.68 (−0.80 to −0.57) | 203 | 0.94 (1.8) | 1.19 (0.96 to 1.42) |
| Never/infrequent | 2639 | 0.13 (0.98) | 0 (reference) | 2679 | 0.2 (0.97) | 0 (reference) | 1755 | −0.26 (1.6) | 0 (reference) |
*Mean of least squares dose-response slope (% decline in FEV1 per μmol methacholine).
CI, confidence interval; FEF25–75, mid forced expiratory flow; FEV1, forced expiratory volume in 1 s; SD, standard deviation.