Baseline characteristics of the two treatment groups
| Amoxicillin/clavulanic acid N=18 | Placebo N=17 | p Value | |
|---|---|---|---|
| Gender (number of men (%)) | 9 (50) | 12 (71) | 0.21 |
| Smoking status (number (%)) | 0.42 | ||
| Ex-smokers | 14 (78) | 11 (65) | |
| Current smokers | 4 (22) | 6 (35) | |
| Age (median (range)) | 68 (54–74) | 65 (47–76) | 0.38 |
| Lung function postbronchodilation at inclusion (SD) | |||
| FEV1 in litres | 1.24 (0.44) | 1.53 (0.54) | 0.06 |
| FEV1% predicted | 44.7 (15.4) | 52.2 (15.1) | 0.16 |
| FEV1/VC % | 38.3 (13.0) | 42.9 (11.2) | 0.27 |
| Positive Gram's stain (number (%)) | 15 (83) | 15 (88) | 1.00 |
| Sputum culture at inclusion (Number (%)) | 0.18 | ||
| No colonisation nor infection | 3 (17) | 5 (29) | |
| Colonisation | 2 (11) | 5 (29) | |
| Infection | 13 (72) | 7 (41) | |
| AECOPDs in the previous year (number (%)) | 0.63 | ||
| <2 AECOPDs | 7 (39) | 8 (47) | |
| ≥2 AECOPDs | 11 (61) | 9 (53) | |
| Lung function decline of ≥200 mL and ≥12% at start of AECOPD compared to baseline* (number (%)) | 2 (11) | 2 (12) | 1.00 |
| Sputum colour score† (SD) | 4.4 (1.2) | 3.4 (1.1) | 0.02 |
| Purulent sputum (number (%)) | 17 (94) | 13 (77) | 0.17 |
| Type of AECOPD according to Anthonisen (number (%)) | 0.44 | ||
| Type I (3 major symptoms) | 15 (83) | 12 (71) | |
| Type II (2 major symptoms) | 3 (17) | 5 (29) | |
| Type III (1 major+1 minor symptom) | 0 | 0 | |
| Procalcitonin level (µg/L) (median (range)) | 0.06 (0.03–0.22) | 0.06 (0.04–0.11) | 0.42 |
| Procalcitonin cut-off level (number (%)) | 1.00 | ||
| <0.1 µg/L | 17 (94) | 16 (94) | |
| 0.1–0.25 µg/L | 1 (6) | 1 (6) | |
| >0.25 µg/L | 0 | 0 | |
To identify variables that were different by treatment group, t tests in case of normally distributed variables were performed. For not normally distributed variables this was performed by Mann-Whitney U test. Between-group comparisons of categorical variables were performed by χ2 tests or Fisher's Exact tests as appropriate.
*Baseline lung function was an earlier in stable state performed lung function measurement.
†Score according to the Stockley protocol with the nine-point colour chart (Bronko Test, Heredilab Inc, Salt Lake City, Utah, USA).
AECOPD, acute exacerbations chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 s; VC, vital capacity.