Individual and area-level social inequalities in asthma prevalence in school children
The evidence on the relationship between social and economic indicators and health outcomes in children is mixed. Most published studies focused on individual-level associations while small-area level social characteristics have rarely been investigated. As a part of the DRIVERS EC-funded FP7 project we aimed to evaluate the role of individual, household and neighbourhood-level social indicators, together with potential cross-level interactions, in the risk of developing asthma among school children in representative UK sample.
METHODS:
Data on 12,844 children aged 0-7 years from first four waves of UK Millennium Cohort Study (MCS) were used in the analysis. Individual data included occupational position of parents, maternal education, household income, mother’s marital status and range of covariates. Data on all participants were linked with Index of Multiple Deprivation (IMD) 2007 and its domains. The role of individual and area-level characteristics was evaluated by multilevel regression modelling.
RESULTS:
The results show that both individual and area-level indicators are important determinants of childhood asthma. In fully adjusted model, those in families in the lowest quintile of income had 25% higher odds of developing asthma by the age of 7 years compared to those in the highest quintile of income (P<0.05). Those living in neighbourhoods within bottom three deciles of IMD had 21-40% higher odds of developing asthma than those living in top decile of IMD neighbourhoods (p<0.05). While gender interactions were not statistically significant, the role of family income was particularly strong in boys with OR 1.64 (95%CI 1.24-2.17) comparing those in the lowest and the highest income quintiles.
CONCLUSIONS:
The results of this project will improve our knowledge about the role of social circumstances both at individual and area level in development of asthma, and may help to identify interventions aiming to reduce inequalities in child health outcomes.