Anderson, H. R.; Ruggles, R.; Pandey, K.D.; Kapetanakis, V.; Brunekreef, B.; Lai, C. K. W.; Strachan, D. P.; Weiland, S. K.; Aït-Khaled, N.; Anabwani, G.; Asher, M. I.; Beasley, R.; Björkstén, B.; Burr, M. L.; Crane, J.; Keil, U.; Mallol, J.; Martinez, F. C.; Mitchell, E. A.; Montefort, S.; Pearce, N.; Robertson, C. F.; Shah, J. R.; Stewart, A. W.; Mutius, Erika von; Williams, H. C.; Clayton, T. O.; Ellwood, P.
Ambient particulate pollution and the world-wide prevalence of asthma, rhinoconjunctivitis and eczema in children: Phase One of the International Study of Asthma and Allergies in Childhood (ISAAC).
In: Occupational and Environmental Medicine, Vol. 67, Nr. 5: S. 293-300
Objectives: To investigate the effect of ambient particulate matter on variation in childhood prevalence of asthma, rhinoconjunctivitis and eczema.
Methods: Prevalences of asthma, rhinoconjunctivitis and eczema obtained in Phase One of the International Study of Asthma and Allergies in Childhood (ISAAC) were matched with city-level estimates of residential PM10 obtained from a World Bank model. Associations were investigated using binomial regression adjusting for GNP per capita and for clustering within country. For countries with more than one centre, a two stage meta-analysis was carried out. The results were compared with a meta-analysis of published multi-centre studies.
Results: Annual concentrations of PM₁₀ at city level were obtained for 105 ISAAC centres in 51 countries. After controlling for GNP per capita, there was a weak negative association between PM₁₀ and various outcomes. For severe wheeze in 13-14-year-olds, the OR for a 10 μg/m³ increase in PM₁₀ was 0.92 (95 CI 0.84 to 1.00). In 24 countries with more than one centre, most summary estimates for within-country associations were weakly positive. For severe wheeze in 13-14-year-olds, the summary OR for a 10 μg/m³ increase in PM₁₀ was 1.01 (0.92 to 1.10). This result was close to a summary OR of 0.99 (0.91 to 1.06) obtained from published multi-centre studies.
Conclusions: Modelled estimates of particulate matter at city level are imprecise and incomplete estimates of personal exposure to ambient air pollutants. Nevertheless, our results together with those of previous multi-centre studies, suggest that urban background PM₁₀ has little or no association with the prevalence of childhood asthma, rhinoconjunctivitis or eczema either within or between countries.