Table 5—

Association between exposure to air pollution and infections, asthmatic and allergic symptoms at 4 yrs of age for the full cohort based on recent and early-life risk factors

OR (95% CI)
UnadjustedSubjects nAdjusted#Subjects nAdjusted-early lifeSubjects n
Wheeze
PM2.51.20 (1.02–1.42)*35221.23 (1.00–1.51)*25771.20 (0.99–1.46)2825
Soot1.19 (1.03–1.38)*35221.18 (0.98–1.41)25771.18 (1.00–1.40)*2825
NO21.14 (0.99–1.31)35221.13 (0.95–1.34)25771.16 (0.98–1.36)2825
Doctor-diagnosed asthma
PM2.51.21 (0.92–1.60)35271.15 (0.82–1.62)25751.32 (0.96–1.83)2826
Soot1.23 (0.97–1.56)35271.15 (0.85–1.55)25751.30 (0.98–1.71)2826
NO21.20 (0.96–1.51)35271.12 (0.84–1.49)25751.29 (0.99–1.69)2826
Dry cough at night
PM2.51.19 (1.04–1.36)*35311.11 (0.94–1.31)25781.14 (0.98–1.33)2830
Soot1.19 (1.06–1.34)*35311.13 (0.97–1.30)25781.14 (1.00–1.31)*2830
NO21.17 (1.05–1.30)*35311.11 (0.97–1.28)25781.11 (0.97–1.26)2830
Doctor-diagnosed bronchitis
PM2.50.96 (0.77–1.21)34960.88 (0.66–1.18)25590.86 (0.66–1.11)2807
Soot0.98 (0.80–1.20)34960.90 (0.69–1.16)25590.88 (0.69–1.11)2807
NO20.97 (0.80–1.17)34960.90 (0.70–1.15)25590.89 (0.71–1.12)2807
Ear/nose/throat infections
PM2.51.11 (0.98–1.25)35431.13 (0.98–1.31)25871.17 (1.02–1.34)*2839
Soot1.12 (1.00–1.24)*35431.15 (1.01–1.31)*25871.16 (1.03–1.31)*2839
NO21.13 (1.03–1.25)*35431.17 (1.03–1.32)*25871.18 (1.05–1.32)*2839
Doctor-diagnosed flu/serious cold
PM2.51.17 (1.02–1.33)*35151.21 (1.02–1.42)*25721.25 (1.07–1.46)*2820
Soot1.16 (1.03–1.30)*35151.18 (1.02–1.36)*25721.19 (1.04–1.37)*2820
NO21.13 (1.01–1.27)*35151.14 (1.00–1.31)25721.17 (1.02–1.33)*2820
Itchy rash
PM2.51.07 (0.95–1.22)35310.96 (0.82–1.11)25820.98 (0.85–1.14)2832
Soot1.06 (0.95–1.18)35310.94 (0.82–1.08)25820.97 (0.85–1.10)2832
NO21.05 (0.95–1.17)35310.95 (0.83–1.08)25820.97 (0.86–1.10)2832
Doctor-diagnosed eczema
PM2.51.10 (0.97–1.25)34641.00 (0.83–1.21)25710.98 (0.82–1.17)2819
Soot1.09 (0.98–1.22)34640.99 (0.84–1.17)25710.97 (0.83–1.14)2819
NO21.06 (0.95–1.17)34641.00 (0.85–1.17)25710.97 (0.83–1.14)2819
  • OR: odds ratio; CI: confidence interval; PM2.5: particles with a 50% cut-off aerodynamic diameter of 2.5 μm; NO2: nitrogen dioxide. #: Adjusted for confounders in table 3 and mothers' age at time of birth, but not region; : adjusted for confounders in table 3 from earliest year available (instead of at 4 yrs) i.e. smoking in the home, gas stove, unvented gas water heater, any other siblings and any mould or pets in home. ORs are calculated for an interquartile range increase in annual average concentration at birth address. *: Significant association, p<0.05.