Asthma in urban Aboriginal children: A cross-sectional study of socio-demographic patterns and associations with pre-natal and current carer smoking.

Abstract

To describe socio-demographic patterns of asthma prevalence in urban Aboriginal children and quantify associations between asthma prevalence and pre-natal maternal and current carer smoking. Analyses used carer-reported survey data for 1290 urban Aboriginal children aged 2-17 years from the Study of Environment on Aboriginal Resilience and Child Health. Multilevel log-binomial regression was used to estimate asthma prevalence ratios (PRs) for child- and family-level socio-demographic factors, pre-natal maternal smoking and current carer smoking. Smoking-related PRs were compared with general-population estimates derived from meta-analyses of published cross-sectional data. Overall, 33.9% of children had ever had asthma, and 12.9% had received treatment for asthma in the past month. Prevalence estimates declined with increasing household income and increasing household size (posterior probabilities of decreasing trend >0.98), while children exposed to pre-natal maternal smoking had a higher risk of asthma ever than unexposed children (PR 1.18 (95% credible interval 1.00-1.40)). Recently treated asthma prevalence was not significantly associated with pre-natal maternal (0.98 (0.71-1.41)) or current carer smoking (0.97 (0.68-1.37)); however, there was substantial uncertainty in our PR estimates, and 95% credible intervals contained general-population estimates derived from the meta-analyses (1.37 (1.17-1.65) for pre-natal smoking, 1.28 (1.15-1.44) for current parental or household smoking). Among urban Aboriginal children in the Study of Environment on Aboriginal Resilience and Child Health cohort, asthma prevalence declines as household income and household size increase, while children exposed to pre-natal maternal smoking are at increased risk of ever having asthma. Our results emphasise the importance of reducing smoking in Aboriginal communities, particularly among pregnant women.