Table 2

 Baseline characteristics of subjects stratified in tertiles defined by the baseline eosinophil differential cell count

Eosinophil count
<1 (n = 20)1–3.9 (n = 20)>3.9 (n = 20)
FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; BD, bronchodilator; CRQ, Chronic Respiratory Disease Questionnaire; TCC, total cell count; IL-8, interleukin 8; ECP, eosinophilic cationic protein; SOB, shortness of breath; VAS, visual analogue score.
†Mean (SE), ‡geometric mean (log SE), ¶median (IQR).
*p<0.05 comparison across groups (ANOVA or Kruskal-Wallis test).
Male101515
Age (years)†66 (2)68 (2)68 (2)
Current smoker595
Ex-smokers141114
Pack years†40 (5)41 (6)39 (5)
Treated with long actingβ2 agonists (n)434
Atopic (subjects with +ve RAST)769
IgE (kU/l)†77 (21)63 (13)197 (53)*
Blood eosinophil count (×109/l)‡0.15 (0.02)0.25 (0.04)0.37 (0.06)*
Total CRQ†4.0 (0.3)3.9 (0.2)4.5 (0.3)
FEV1 (l)†1.35 (0.13)1.29 (0.1)1.03 (0.09)
FEV1 BD (l)†1.47 (0.14)1.42 (0.11)1.09 (0.1)
FEV1 (% predicted)†47 (3)47 (3)38 (3)
FVC (l)†2.5 (0.2)2.3 (0.2)2.2 (0.2)
Sputum characteristics
    Eosinophils (%)¶0.4 (0.1)2 (0.04)7.5 (0.05)
    Neutrophils (%)¶67 (41–89)81 (68–84)80 (65–89)
    Macrophages (%)¶29 (10–53)14 (9–27)10 (4–24)
    Lymphocytes (%)¶0.5 (0.16–0.9)0.8 (0.05–1.25)0.2 (0–0.7)
    Epithelial cells (%)¶0.8 (10.2–2.2)0.9 (0.2, 2.4)0.9 (0.2–2.5)
    TCC (×106 cells/g sputum)†4.8 (1.4)2.9 (0.5)3.7 (1.0)
    Histamine (ng/g)‡45 (0.17)84 (0.16)48 (0.1)
    IL-8 (ng/g)‡135 (0.9)100 (0.08)142 (0.1)
    ECP (ng/g)‡687 (0.09)998 (0.1)1769 (0.2)
CRQ domain scores
    Dyspnoea†3.3 (0.3)3.1 (0.3)3.7 (0.3)
    Fatigue†3.6 (0.3)3.5 (0.2)4.0 (0.3)
    Emotion†4.4 (0.3)4.5 (0.2)4.9 (0.3)
    Mastery†4.5 (0.3)4.5 (0.3)5.3 (0.3)
Symptom scores (VAS)
    Cough (mm)†35 (7)34 (6)43 (7)
    Sputum (mm)†25 (6)38 (6)26 (5)
    SOB (mm)†51 (7)48 (5)45 (7)
    Wheeze (mm)†27 (6)25 (5)32 (6)