Baseline characteristics of the total chronic obstructive pulmonary disease (COPD) cohort
| Total patients | 127 |
| Continuous variables | |
| Age years | 66.8±8.61 |
| Smoking history pack-years | 50.3±28.2 |
| Body mass index kg·m–2 | 27.0 (6.69) |
| Fat-free body mass % | 48.9 (21.5) (n=125) |
| White blood cells count ×109 L–1 | 7.60 (2.20) (n=126) |
| Eosinophils count ×109 L–1 | 0.20 (0.20) (n=126) |
| Eosinophils % | 2.94 (3.08) (n=126) |
| Neutrophils count ×109 L–1 | 4.80 (1.70) (n=126) |
| Fibrinogen g·L–1 | 4.80 (1.02) (n=114) |
| C-reactive protein mg·L–1 | 5.00 (8.00) |
| Eosinophils %# | 1.93 (5.05) (n=83) |
| Neutrophils %# | 47.0 (70.4) (n=83) |
| FEV1 % pred | 46.7 (25.3) (n=126) |
| ΔFEV1 % of baseline¶ | 4.93 (21.1) (n=85) |
| FEV1 reversibility % of pre-bronchodilator FEV1+ | 11.2 (17.0) (n=105) |
| KCO % | 69.2 (30.7) (n=122) |
| TLCO % | 57.9 (29.5) (n=122) |
| CAT score | 16.0 (10.0) (n=126) |
| 6MWT distance m | 300 (170) (n=125) |
| EXACT-PRO score | 37.0 (12.0) (n=101) |
| Exacerbation rate in year before study | 2.00 (2.00) |
| Exacerbation rate in first year of study | 2.94 (3.91) |
| Eosinophilic exacerbation rate in first year of study | 0.99 (2.02) |
| Follow-up in first year of study years | 1.00 (0.02) |
| Categorical variables | |
| Sex | |
| Male | 68 (54) |
| Female | 59 (46) |
| Current smoker§ | |
| Yes | 54 (43) |
| No | 73 (57) |
| Frequent exacerbators in year 0 | |
| Yes | 99 (78) |
| No | 28 (22) |
| Use of ICS at enrolmentƒ | |
| Yes | 113 (89) |
| No | 14 (11) |
| Sputum eosinophils >3%# | |
| Yes | 27 (33) |
| No | 56 (67) |
| Blood eosinophils ≥2% | |
| Yes | 86 (68) |
| No | 40 (32) |
| Bacteria present## | |
| Yes | 57 (52) |
| No | 53 (48) |
| Virus present¶¶ | |
| Yes | 18 (17) |
| No | 85 (83) |
| Blood eosinophils ≥200 cells·μL–1 | |
| Yes | 90 (71.4) |
| No | 36 (28.6) |
Data are presented as n for patient numbers, mean±sd or median (interquartile range) for continuous variables, or n (%) for categorical variables. FEV1: forced expiratory volume in 1 s; KCO: transfer coefficient of the lung for carbon monoxide; TLCO: transfer factor of the lung for carbon monoxide; CAT: COPD Assessment Test; 6MWT: 6-min walk test; ICS: inhaled corticosteroid. #: sputum eosinophil and neutrophil percentage at baseline is reported (“baseline” is equal to enrolment if good quality data (squamous cell contamination <30%) is present at enrolment or the next (pre-exacerbation) stable visit with quality data within 4 months of enrolment); ¶: calculated as FEV1 at month 12×100/FEV1 at enrolment; +: calculated as (post-bronchodilator FEV1–pre-bronchodilator FEV1)/pre-bronchodilator FEV1×100; §: smoking status report derived from American Thoracic Society Division of Lung Disease questionnaire ATS-DLD-78A; ƒ: ICS use was coded as “Yes” if one of the following medications/inhalers was on the list: Symbicort, Seretide, QVAR, Fostair, beclomethasone, beclomethasone/formoterol, beclomethasone dipropionate, Clenil, fluticasone/salmeterol or budesonide/formoterol; ##: sputum sampling, measured by culture (includes Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pneumoniae, Staphylococcus aureus and Pseudomonas aeruginosa); ¶¶: sputum sampling, measured by PCR (includes adenovirus, enterovirus, influenza, coronavirus, metapneumovirus, bocavirus, parainfluenza, respiratory syncytial virus and rhinovirus).