P13 Associations of adiposity in infancy and early childhood with infantile and early childhood atopic eczema

Abstract Introduction and aims Adiposity in early life has been associated with an increased risk of infantile and childhood atopic eczema but evidence for this has been inconsistent. Examining this association can help identify mechanisms which influence the risk of developing atopic eczema and point to measures that may help prevent or control the condition. The aim of this study was to examine the association between adiposity and atopic eczema through infancy and early childhood. Methods Within the Southampton Women Survey, infant/child total body fat was assessed using dual-energy X-ray absorptiometry (DXA) as means of evaluating body composition at birth (n = 933), 4 years (n = 797) and 6 years (n = 1141). Atopic eczema was ascertained using the UK Working Party Diagnostic Criteria at ages 6 months (n = 154/1679, 12 months (n = 174/1655), 3 years (n = 233/1583) and 6 years (n = 217/1427). A directed acyclic graph determined confounders, which were: maternal body mass index, education, smoking during pregnancy, maternal history of eczema in the last 12 months, parity and infant sex. Analyses also adjusted for infant gestational age and age of DXA scan as they directly impact total body fat. Logistic regressions examined the associations between total body fat and atopic eczema at the various timepoints. Results Total body fat at birth, 4 years and 6 years were not related to atopic eczema in infancy or early childhood. However, total body fat > 80th centile at age 4 years was associated with a higher risk of atopic eczema at age 6 years and remained significant after adjusting for confounders (adjusted odds ratio 1.69, 95% confidence interval 1.03–2.77; P = 0.04). Conclusions These findings suggest that excess total body fat > 80th centile in early childhood is associated with a higher risk of childhood atopic eczema. Further research is needed to establish the mechanisms that link excess adiposity at age 4 years and atopic eczema in childhood.