TABLE 5

Biomarkers in blood, sputum and exhaled air

Severe nonsmoking asthmaSmokers and ex-smokers with severe asthmaMild/moderate nonsmoking asthmaHealthy nonsmoking controlsp-valuep-value#
Subjects n31111088101
Exhaled NO ppb26.5 (16−47) (n=290)23.5 (12−42) (n=104)25 (18−54) (n=87)19.25 (13−29) (n=96)<0.0010.438
Sputum
 Sputum eosinophils %2.75 (0−19) (n=128)4.13 (1−14) (n=53)1.05 (0−3) (n=43)0 (0−0) (n=41)<0.0010.004
 Sputum neutrophils %53.69 (34−75) (n=128)55.15 (35−65) (n=53)44.5 (26−62) (n=43)39.56 (21−56) (n=41)0.0020.042
 Sputum differential eosinophil count >1.9%74 (57.81%) (n=128)32 (60.38%) (n=53)17 (39.53%) (n=43)1 (2.44%) (n=41)<0.0010.026
Blood
 Blood eosinophils %2.94 (1−6) (n=302)2.88 (1−5) (n=106)3.00 (2−5) (n=88)2.10 (1−3) (n=101)0.0010.295
 Blood eosinophils absolute0.2 (0.3) (n=302)0.22 (0.29) (n=106)0.23 (0.2) (n=88)0.1 (0.11) (n=101)0.0010.295
 Blood neutrophils %62 (55−70) (n=302)61.75 (55−69) (n=106)56.83 (52−63) (n=88)57.34 (51−64) (n=101)<0.001<0.001
 Blood neutrophils absolute4.73 (3.1) (n=302)4.97 (2.87) (n=106)3.64 (1.75) (n=88)3.03 (1.6) (n=101)<0.001<0.001

Data are presented as median (interquartile range), unless otherwise stated. #: severe asthma (nonsmoking asthma group and smokers and ex-smokers with severe asthma group combined) versus mild/moderate nonsmoking asthma group.