TABLE 4

Season-specific#estimates for the associations between personal exposure to air pollutants and peak expiratory flow (PEF) and exacerbation

Spring Summer Autumn Winter
PEF Exacerbation PEF Exacerbation PEF Exacerbation PEF Exacerbation
PM2.5 −0.011
(−0.059–0.037)		 0.986
(0.975–0.997)*		 −0.122
(0.186 - 0.058−−)*		 1.010
(1.000–1.021)*		 0.012
(−0.041–0.065)		 1.000
(0.994–1.005)		 0.018
(−0.018–0.053)		 0.995
(0.990–0.999)*
PM10 −0.003
(−0.042–0.035)		 1.001
(0.993–1.010)		 −0.063
(−0.113– −0.014)*		 1.006
(0.998–1.015)		 0.006
(−0.048–0.060)		 1.000
(0.994–1.005)		 0.011
(−0.027–0.049)		 0.992
(0.987–0.998)*
NO2 −0.119
(−0.248–0.011)		 1.008
(0.982–1.034)		 0.059
(−0.156–0.275)		 1.024
(0.976–1.074)		 −0.115
(−0.368–0.138)		 1.003
(0.964–1.043)		 0.063
(−0.092–0.218)		 0.970
(0.942–0.999)*
NO 0.034
(−0.136–0.205)		 1.000
(0.970–1.031)		 −0.027
(−0.171 - -0.117)		 1.030
(0.988–1.073)		 0.002
(−0.084–0.088)		 1.002
(0.990–1.014)		 −0.006
(−0.058–0.046)		 1.009
(1.001–1.017)*
CO −0.009
(−0.082–0.064)		 0.996
(0.982–1.011)		 0.052
(−0.031–0.135)		 1.001
(0.985–1.018)		 −0.096
(−0.209–0.016)		 1.005
(0.988–1.022)		 −0.012
(−0.074–0.050)		 1.007
(0.995–1.018)
O3 0.009
(−0.113–0.132)		 1.028
(1.004–1.052)*		 0.035
(−0.099–0.169)		 1.016
(0.987–1.045)		 −0.169
(−0.515–0.177)		 0.969
(0.913–1.029)		 0.008
(−0.411–0.427)		 1.149
(1.074–1.229)*

Data are presented as estimated change in PEF (L·min−1)或f比值比or exacerbation with 95% confidence interval by season per unit increase (models adjusted for age, sex, chronic obstructive pulmonary disease severity, Index of Multiple Deprivation rank, inhaled corticosteroid medication use, temperature and time). PM2.5: particulate matter with aerodynamic diameter <2.5 μm; PM10: particulate matter with aerodynamic diameter <10 μm; NO2: nitrogen dioxide; NO: nitric oxide; CO: carbon monoxide; O3: ozone.#: spring n=4495, summer n=4507, autumn n=2769, winter n=2969;: per 0.01 ppm increase. *: statistically significant estimates (p<0.05).