Table 5 COPD diagnosis and chronic bronchitis symptoms in relation to traffic.

n

n, (%)

OR ^a

n

n, (%)

OR ^a

Heavy traffic

No

6041

243(4.0%)

1.00

6041

401(6.6%)

1.00

Yes

3275

172(5.3%)

1.36(1.10–1.67)

3275

234(7.1%)

1.11(0.94–1.31)

Heaviest road within <100 m

no heavy road

3755

153(4.1%)

1.00

3755

222(5.9%)

1.00

<2 cars/min

2235

95(4.3%)

1.04(0.80–1.35)

2235

159(7.1%)

1.21(0.98–1.50)

2–5 cars/min

1820

71(3.9%)

0.96(0.72–1.28)

1820

137(7.5%)

1.30(1.04–1.62)

6–10 cars/min

886

60(6.8%)

1.57(1.15–2.14)

886

67(7.6%)

1.24(0.93–1.65)

>10 cars/min

578

34(5.9%)

1.64(1.11–2.41)

578

48(8.3%)

1.53(1.10–2.13)

NO_x (μg/m³)

0–8

1855

74(4.0%)

1.00

1855

110(5.9%)

1.00

8–11

1855

68(3.7%)

0.89(0.63–1.24)

1855

118(6.4%)

1.05(0.81–1.38)

11–14

1855

87(4.7%)

1.19(0.86–1.64)

1855

121(6.5%)

1.12(0.86–1.46)

14–19

1858

83(4.5%)

1.03(0.74–1.42)

1858

122(6.6%)

1.06(0.81–1.39)

>19

1851

101(5.5%)

1.43(1.04–1.95)

1851

162(8.8%)

1.55(1.21–2.00)

p-trend

0.010

p-trend

<0.0001