Childhood Type 1 Diabetes

Abstract

PDS 71: Exposome, Johan Friso Foyer, Floor 1, August 27, 2019, 4:30 PM - 5:30 PM Background/Aim: Type 1 Diabetes (T1D) is an autoimmune disease affecting ~400,000 people across the UK. Environmental factors likely trigger the disease process in genetically susceptible individuals. We assessed the associations between a wide range of environmental factors and childhood T1D incidence in England, using an agnostic, ecological Environment Wide Association Study (EWAS) approach, to generate hypotheses about environmental triggers. Methods: We undertook analyses at the Local Authority District (LAD) level using a national Hospital Episode Statistics (HES) based incident T1D dataset, comprising 13,948 cases aged 0-9 years over the period April 2000- March 2011. We compiled LAD-level estimates for a range of potential demographic and environmental risk factors including meteorological, land use and environmental pollution variables. The associations between T1D incidence and risk factors were assessed via Poisson regression, disease mapping and ecological regression. Results: Case counts by LAD varied from 1 to 236 (median 33; inter quartile range: 24-46). Overall T1D incidence was 21.2 (95% CI 20.9-21.6) per 100,000 individuals. The EWAS and disease mapping indicated that 15 out of 53 demographic and environmental risk factors were significantly associated with diabetes incidence after adjusting for multiple testing. These included air pollutants (particulate matter, nitrogen dioxide, nitrogen oxides, carbon monoxide), as well as lead in soil, radon, outdoor light at night, overcrowding, population density and ethnicity. Disease mapping revealed spatial heterogeneity in T1D risk. The ecological regression found a significant association between T1D and the living environment domain of the Index of Multiple Deprivation (RR 0.995 (95%CI 0.991-0.998)) and radon potential class (RR 1.044 95%CI 1.015-1.074). Conclusions: Our analysis identifies a range of demographic and environmental factors associated with T1D in children in England.