|
Variable
|
Group
|
Estimatea
|
95 % CI
|
P value
|
|---|
|
Nitrite + nitrate (NOx)
|
COPD
|
3.15
|
(1.41, 7.04)
|
0.007
|
|
Control
|
0.49
|
(0.14, 1.65)
|
0.23
|
|
8-Isoprostane
|
COPD
|
0.44
|
(0.05, 3.61)
|
0.43
|
|
Control
|
2.34
|
(0.18, 29.73)
|
0.49
|
|
FEV1 (L)
|
COPD
|
0.01
|
(-0.10, 0.12)
|
0.85
|
|
Control
|
0.01
|
(-0.10, 0.11)
|
0.90
|
|
FVC (L)
|
COPD
|
−0.17
|
(-0.37, 0.03)
|
0.09
|
|
Control
|
−0.01
|
(-0.12, 0.09)
|
0.80
|
|
Aggregate symptom score
|
COPD
|
3.47
|
(1.01, 5.93)
|
0.008
|
|
Control
|
2.02
|
(-0.92, 4.95)
|
0.16
|
-
a Displayed are estimated ratios of geometric mean levels (with 95 % CIs and p-values) of 8-isoprostane and NOx between pollution and clean air days, as well as estimated mean differences (with 95 % CIs and p-values) in FEV1, FVC, and aggregate symptom score between pollution and clean air days in a) COPD patients and b) Control group participants
