Pathways from socioeconomic deprivation to bronchiolitis and subsequent childhood asthma

Acute and chronic respiratory conditions are a major cause of morbidity amongst children in the UK, and are responsible for substantial burden on children, their families and the health care system. In infants, infection of the lungs (bronchiolitis) is the most common cause of hospitalisation in England. Asthma is another respiratory condition that is highly prevalent amongst children in the UK. Despite wide agreement that hospital admission for acute respiratory infection is associated with an increased risk of asthma at an older age, there is an ongoing debate about the nature of this association. Discussions focus on a directly causative or a genetic predetermined signal explanation to explain this relationship, without fully considering the role of other risk factors.

An overriding facet of both conditions is the inequity in prevalence across socioeconomic groups. An unknown proportion of the association between socio-economic status, infant bronchiolitis, and subsequent asthma is due, to common risk factors operating in utero such as tobacco smoke exposure, fetal growth and prematurity. It is therefore important, as there is no cure available for the majority of these conditions, that we fully understand what causes these health problems to occur. This is particularly important amongst children who are known to be socially disadvantaged, and are placed at a greater risk for these diseases and other chronic conditions.


The overall aim of this project is to understand the causal pathways between socioeconomic deprivation and respiratory conditions in early and mid-childhood (see Figure 1). I will primarily use national English and Scottish birth cohorts, created from administrative health records, to meet the specific study objectives:

1. To describe the association between socioeconomic deprivation, seasonality and acute respiratory infection in infancy
2. To establish to what extent maternal and perinatal risk factors, including in-utero pollution exposure, mode of delivery, birth weight, gestational age and chronic conditions mediates the association between socioeconomic deprivation and acute respiratory infection in infancy
3. To describe asthma/wheeze phenotypes in children aged <10 years old and their associated risk factors, including socio-economic position
4. To determine the total contribution of early acute respiratory infection to the effect of socio-economic deprivation on mid-childhood asthma/wheeze phenotypes.

Overall, I will determine at what time, and for which risk factors, interventions would reduce the most inequity and overall burden of respiratory conditions in childhood.