Associations with persistence of air trapping
| Clinical factors | Change in air trapping status | Model 1* | Model 2† | |||
| Transient | Persistent | OR (95% CI) | p Value | OR (95% CI) | p Value | |
| Age | 2.2 (1.2–3.4) | 2.0 (1.0–3.2) | 0.86 (0.70 to 1.07) | 0.175 | 0.76 (0.59 to 0.97) | 0.028 |
| Sex (female) | 50% (21/42) | 54% (97/178) | 1.17 (0.58 to 2.37) | 0.657 | – | – |
| Severe CFTR genotype | 88% (29/33) | 93% (160/172) | 1.83 (0.51 to 6.57) | 0.355 | – | – |
| Pancreatic sufficiency | 17% (7/42) | 11% (19/178) | 0.53 (0.20 to 1.42) | 0.208 | – | – |
| Respiratory symptoms at the initial scan | 19% (8/42) | 20% (36/178) | 1.18 (0.51 to 2.74) | 0.697 | – | – |
| Respiratory symptoms at the subsequent scan | 13% (5/40) | 21% (36/172) | 1.95 (0.73 to 5.17) | 0.180 | – | – |
| CT factors | ||||||
| Detectable bronchiectasis at the initial scan | 52% (22/42) | 48% (86/178) | 0.99 (0.49 to 2.02) | 0.986 | – | – |
| Bronchiectasis extent at the initial scan | 1 (0–3) | 0 (0–5) | 1.19 (0.98 to 1.43) | 0.072 | – | – |
| Detectable bronchiectasis at the subsequent scan | 60% (25/42) | 68% (121/178) | 1.69 (0.83 to 3.44) | 0.152 | – | – |
| Bronchiectasis extent at the subsequent scan | 1 (0–4) | 1 (0–7) | 1.22 (1.04 to 1.42) | 0.013 | – | – |
| Change in bronchiectasis extent | 0 (−1–4) | 1 (0–4) | 1.18 (1.00 to 1.40) | 0.048 | – | – |
| Air trapping extent at the initial scan | 2 (1–5) | 4 (2–7) | 1.34 (1.13 to 1.60) | 0.001 | – | – |
| Bronchoalveolar lavage factors at the initial scan | ||||||
| Uninfected | 43% (18/42) | 31% (55/177) | (Comparator) | (Comparator) | ||
| Mixed oral flora | 26% (11/42) | 27% (47/177) | 1.32 (0.57 to 3.06) | 0.523 | 0.89 (0.35 to 2.30) | 0.814 |
| Infected | 31% (13/42) | 42% (75/177) | 1.95 (0.87 to 4.37) | 0.105 | 1.49 (0.57 to 3.92) | 0.416 |
| Detectable neutrophil elastase | 22% (9/41) | 34% (61/177) | 1.75 (0.81 to 3.81) | 0.156 | – | – |
| Inflammatory response score | −0.43 (−1.04–0.74) | 0.07 (−1.02–1.19) | 1.20 (0.98 to 1.49) | 0.083 | 1.02 (0.79 to 1.32) | 0.885 |
| Bronchoalveolar lavage factors at the subsequent scan | ||||||
| Uninfected | 40% (17/42) | 25% (44/177) | (Comparator) | (Comparator) | ||
| Mixed oral flora | 26% (11/42) | 22% (39/177) | 1.39 (0.58 to 3.35) | 0.461 | 1.33 (0.49 to 3.63) | 0.572 |
| Infected | 33% (14/42) | 53% (94/177) | 2.83 (1.26 to 6.36) | 0.012 | 2.54 (0.96 to 6.71) | 0.060 |
| Detectable neutrophil elastase | 21% (9/42) | 37% (66/178) | 2.13 (0.97 to 4.67) | 0.060 | – | – |
| Inflammatory response score | −0.32 (−1.05–0.65) | 0.47 (−0.63–1.33) | 1.23 (0.98 to 1.53) | 0.071 | 1.10 (0.85 to 1.44) | 0.470 |
| Change in inflammatory response score | 0.11 (−1.05–1.17) | 0.45 (−1.81–1.34) | 1.19 (0.94 to 1.49) | 0.150 | – | – |
–Not included in model Bold, significant p-values (<0.05).
Data given as median (25th–75th percentile) or percentage (raw data) as appropriate.
↵* Model 1: Each variable analysed in a separate model after adjusting for age at the initial scan.
↵† Model 2: Combined model adjusted for age at initial scan, infection status at the initial and subsequent scans and inflammation status at the initial and subsequent scans.
CFTR, cystic fibrosis transmembrane regulator.