Patient baseline characteristics
| <1 Exacerbation/year n=140 | 1–2 Exacerbations/year n=160 | >2 Exacerbations/year n=146 | Between-group p value | |
| Average follow-up time, years | 2.17 | 2.27 | 2.34 | |
| Total no. of exacerbations | 158 | 710 | 1512 | |
| Average no. of exacerbations/year | 0.52 | 1.95 | 4.43 | |
| Mean age (SD), years | 28.5±9.7 | 29.1±9.1 | 30.2±10.1 | 0.33 |
| Sex (% male) | 96 (68.6%) | 92 (57.5%) | 67 (45.9%) | 0.0005 |
| Mean height (SD), cm | 169.8±9.4 | 169±9.3 | 167.6±8.3 | 0.11 |
| Mean weight (SD), kg | 65.5±12.5 | 64.1±12.6 | 61.9±14.1 | 0.06 |
| Mean BMI (SD), kg/m2 | 22.6±2.9 | 22.4±3.6 | 21.9±4 | 0.25 |
| Lung function | ||||
| FEV1 measured (SD), litres | 2.70±1.00 | 2.26±0.87 | 1.81±0.85 | <0.0001 |
| FEV1 % predicted (SD) | 67.5±20.7 | 59.0±20.8 | 49.1±20.4 | <0.0001 |
| FVC measured (SD), litres | 4.71±0.86 | 5.47±0.83 | 4.37±0.76 | 0.002 |
| FVC % predicted (SD) | 83.4±17.8 | 77.77±20.6 | 67.9±21.6 | <0.0001 |
| Chronic infections, n (%) | ||||
| Achromobacter species | 0 (0%) | 7 (4.4%) | 4 (2.7%) | 0.05 |
| Aspergillus species | 25 (18.4%) | 36 (22.5%) | 56 (38.4%) | 0.0003 |
| Burkholderia cepacia complex | 17 (12.5%) | 24 (15%) | 22 (15.1%) | 0.78 |
| Staphylococcus aureus | 39 (28.7%) | 44 (27.7%) | 37 (25.5%) | 0.83 |
| Stenotrophomonas maltophilia | 6 (4.4%) | 14 (8.8%) | 15 (10.3%) | 0.17 |
| Transmissible Pseudomonas aeruginosa strains | 42 (30.0%) | 28 (17.5%) | 32 (21.9%) | 0.11 |
| Pseudomonas aeruginosa (all strains) | 101 (72.1%) | 101 (68.8%) | 109 (74.7%) | 0.67 |
| Co-morbidities, n (%) | ||||
| CF-related diabetes | 23 (16.4%) | 28 (17.5%) | 41 (28.1%) | 0.02 |
| Pancreatic insufficiency | 116 (82.9%) | 132 (82.5%) | 127 (87%) | 0.50 |
| CF-related liver disease | 4 (2.9%) | 8 (5%) | 11 (7.5%) | 0.20 |
| Medications, n (%) | ||||
| Azithromycin | 30 (21.4%) | 52 (32.5%) | 61 (41.8%) | 0.001 |
| Inhaled colistin | 5 (3.6%) | 8 (5%) | 16 (11%) | 0.03 |
| Dornase α | 10 (7.1%) | 16 (10%) | 31 (21.2%) | 0.0007 |
| Inhaled tobramycin | 86 (61.4%) | 94 (58.8%) | 98 (67.1%) | 0.31 |
BMI, body mass index; CF, cystic fibrosis; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity.