Understanding socio-economic inequalities in childhood respiratory health

Asthma is the most common chronic disease of childhood. Recent evidence hasshown a socio-economic gradient in its distribution. This paper examineswhether a number of factors argued to have led to a rise in the incidence ofasthma might also explain the social gradient. Several of these have been theobject of policy intervention, though not necessarily with the aim of loweringchildhood respiratory conditions. Using a large cohort study (the AvonLongitudinal Study of Parents and Children) we find significant inequalities inthree respiratory conditions in middle childhood. We investigate eight potentialmediating factors: exposure to other children in infancy, child’s diet, poorhousing conditions, maternal smoking, parental history of asthma, poor childhealth at birth, maternal age at child’s birth and local deprivation. We find thateach of these alone typically explains a relatively modest part of eachrespiratory inequality, with child’s diet, local deprivation and maternal smokinggenerally the most important. But taken together, the mediating factors accountfor a substantial part of the respiratory inequalities. So the socio-economicgradient appears to operate through a number of inter-correlated pathways,some of which may be amenable to policy intervention.[...]