Table 1

Summary of assigned pollutant concentrations in 2002 for participants with no diagnosis of COPD by end of 2002 (n=812 063)

Assigned annual average concentration in 2002 (µg/m3)
PM10PM2.5SO2NO2O3
No. with pollution linkage (%)807 401 (99)807 401 (99)800 360 (99)807 000 (99)801 380 (99)
Mean concentration (SD)19.7 (2.3)12.9 (1.4)3.9 (2.1)22.5 (7.4)51.7 (2.4)
IQR3.01.92.210.73.0
Practice region means (SD)
 North [81 practices]19.8 (2.3)12.9 (1.5)4.8 (2.1)23.4 (6.3)50.9 (2.4)
 South (ex. London) [96 practices]19.1 (2.0)12.5 (1.2)3.2 (1.9)19.4 (6.1)52.6 (2.2)
 London [28 practices]22.5 (1.2)14.6 (0.8)3.8 (1.2)33.3 (4.5)50.2 (0.8)
 Test for heterogeneityp<0.001p<0.001p<0.001p<0.001p<0.001
Modified IMD quintile means (SD)
 1 (Most deprived)21.0 (2.2)13.7 (1.5)4.7 (2.2)26.9 (6.3)50.9 (2.1)
 221.1 (2.6)13.8 (1.7)4.2 (2.3)26.5 (7.9)51.3 (2.2)
 320.4 (2.6)13.3 (1.7)4.5 (2.5)24.2 (8.1)51.2 (2.2)
 420.0 (2.3)13.1 (1.5)4.4 (2.5)23.2 (7.5)51.3 (2.2)
 519.5 (2.6)12.7 (1.6)3.9 (2.4)21.6 (8.2)52.1 (2.6)
 619.3 (2.4)12.6 (1.5)3.7 (1.9)21.1 (7.6)51.6 (2.6)
 719.3 (2.3)12.6 (1.4)3.9 (2.1)21.3 (7.5)51.6 (2.6)
 819.3 (2.0)12.6 (1.3)3.6 (1.8)20.9 (6.7)51.8 (2.4)
 919.4 (1.9)12.6 (1.2)3.6 (1.7)21.8 (6.6)51.9 (2.3)
 10 (Least deprived)19.6 (1.5)12.8 (0.9)3.6 (1.3)22.1 (5.6)52.2 (1.9)
 Test for trendp<0.001p<0.001p<0.001p<0.001p<0.001
Correlation* between pollutants
 PM2.50.99
 SO20.450.46
 NO20.840.850.38
 O3−0.40−0.39−0.41−0.47
  • *Spearman's rank correlation coefficient.

  • COPD, chronic obstructive pulmonary disease; IMD, Index of Multiple Deprivation; IQR, interquartile range.