Subject characteristics*
| Healthy subjects | Stable CF patients | Unstable CF patients | |
| N | 31 | 29 | 24 |
| Age, years | 14±0.7 | 15±0.9 | 15±0.7 |
| Sex, F/M | 15/16 | 14/15 | 11/13 |
| FEV1, % predicted | 110.4±2.5 | 86.6±2.9† | 75.7±3.4‡ |
| p<0.001 | p<0.02 | ||
| FVC, % predicted | 113.0±2.2 | 89.1±3.1† | 86.1±4.8† |
| p<0.01 | p<0.05 | ||
| BMI (kg/m2) | 20.3±0.5 | 20.1±0.6 | 19.3±0.7 |
| CRP (mg/l) | – | 0.3±0.1 | 2.0±0.2‡ |
| p<0.0001 | |||
| WBC (×109/l) | – | 8.2±0.4 | 10.6±0.6‡ |
| p<0.004 | |||
| Bacterial infection | |||
| Pseudomonas aeruginosa | – | 16 | 15 |
| Staphylococcus aureus | – | 7 | 6 |
| S aureus + P aeruginosa | – | 3 | – |
| Stenotrophomonas maltophilia | – | 1 | – |
| S aureus + S maltophilia | – | – | 1 |
| S aureus + P aeruginosa + S maltophilia | – | – | 1 |
| Burkholderia cepacia | – | – | 1 |
| CFTR genotype§ | |||
| ΔF508/ΔF508 | – | 5 | 7 |
| ΔF508/other | – | 15 | 11 |
| Other/other | – | 8 | 4 |
| ICS (yes/no) | – | 23/6 | 24/0 |
| Short-acting β2 agonists (yes/no) | – | 25/4 | 23/1 |
| Inhaled tobramycin (yes/no) | – | 17/12 | 17/7 |
| Recombinant human DNase (yes/no) | – | 18/11 | 22/2 |
Age range: healthy subjects: 9–23 years; stable CF patients: 9–24 years; unstable CF years: 9–23 years. Patients with CF with concomitant allergy and/or asthma were excluded from the study. No patient with CF, except one patient with stable CF, had pancreatic insufficiency. Full details of treatment are given in the online supplement.
↵* Data are expressed as n or mean±SEM. One-way ANOVA and unpaired t tests were used for comparing groups. Significance was defined as p<0.05.
↵† Compared with healthy subjects.
↵‡ Compared with patients with stable CF.
↵§ Genotype was not determined in one patient with stable CF and in two patients with unstable CF.
BMI, body mass index; CF, cystic fibrosis; CFTR, cystic fibrosis transmembrane conductance regulator; CRP, C reactive protein; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; ICS, inhaled corticosteroids; WBC, peripheral white blood cell counts.