Table 1

 Patient characteristics

CharacteristicExacerbated(n = 154)Did not exacerbate(n = 95)Odds ratio(95% CI)p value
BMI, body mass index; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity.
Mean (SD) age (years)30.1 (13.8)33.5 (8.8)0.95 (0.92 to 0.98)0.002
Female sex (%)82 (53%)24 (25%)3.37 (1.92 to 5.90)<0.0001
Mean (SD) BMI (kg/m2)21.2 (4.3)22.9 (3.1)0.88 (0.82 to 0.96)0.002
Mean (SD) lung function
    FEV1 (% predicted)48.3 (18.1)63.0 (20.2)0.96 (0.95 to 0.98)<0.0001
    FVC (% predicted)66.4 (20.3)76.9 (19.2)0.97 (0.96 to 0.99)0.0002
CF related diabetes mellitus35 (22.7%)18 (18.9%)1.26 (0.67 to 2.38)0.48
CF related pancreatic insufficiency149 (96.8%)83 (87.4%)4.31 (1.47 to 12.65)0.008
CF related liver disease18 (11.6%)8 (8.4%)1.44 (0.60 to 3.45)0.41
Courses of IV antibiotics for pulmonary exacerbation in past 24 months
    038 (24.7%)61 (64.2%)
    130 (19.5%)19 (20.0%)2.54 (1.26 to 5.12)0.001
    2–340 (26.0%)8 (8.4%)8.03 (3.40 to 18.98)<0.0001
    >346 (29.9%)7 (7.4%)10.55 (4.32 to 25.75)<0.0001
Bacteria in sputum at enrolment
    Burkholderia cepacia complex (BC)55 (35.7%)38 (40%)
    Pseudomonas aeruginosa (PA)78 (50.6%)38 (40%)1.42 (0.81 to 2.50)0.26
    Both BC and PA6 (3.9%)8 (8.4%)0.52 (0.17 to 1.62)0.26
    Other15 (9.7%)11 (11.6%)0.94 (0.39 to 2.27)0.89
New bacterial species in sputum during study8 (5.2%)7 (7.4%)0.69 (0.24 to 1.97)0.49
    Burkholderia cepacia complex20
    Pseudomonas aeruginosa36
    Stenotrophomonous maltophilia10
    Achromobacter xylosoxidans21
    None146 (94.8%)88 (92.6%)
Medications used chronically
    Inhaled corticosteroid89 (57.8%)29 (30.5%)3.12 (1.81 to 5.35)<0.0001
    DNase53 (34.4%)21 (22.1%)1.85 (1.03 to 3.33)0.04
    Inhaled antibiotics
        None54 (35.1%)49 (51.6%)
        Tobramycin78 (50.6%)39 (41.1%)1.82 (1.05 to 3.13)0.03
        Colimycin8 (5.2%)2 (2.1%)3.63 (0.74 to 17.9)0.11
        Tobramycin and colimycin14 (9.1%)5 (5.3%)2.54 (0.85 to 7.57)0.09
    Oral antibiotics
        None101 (65.6%)66 (69.5%)
        Azithromycin21 (13.6%)15 (15.8%)0.92 (0.44 to 1.90)0.81
        Other19 (12.3%)11 (11.6%)1.13 (0.51 to 2.52)0.77
        Azithromycin and other13 (8.4%)3 (3.2%)2.83 (0.78 to 10.32)0.11