Low maternal education increases the risk of Type 1 Diabetes, but not other autoimmune diseases: a mediating role of childhood BMI and exposure to serious life events.

The objective of this paper was to investigate if socioeconomic status (SES), measured by maternal education and household income, influenced the risk of developing autoimmune disease (Type 1 Diabetes, Celiac disease, Juvenile Idiopathic Arthritis, Crohn's disease, Ulcerative colitis, and autoimmune thyroid disease), or age at diagnosis, and to analyse pathways between SES and autoimmune disease. We used data from the All Babies in Southeast Sweden (ABIS) study, a population-based prospective birth cohort, which included children born 1997-1999. Diagnoses of autoimmune disease was collected from the Swedish National Patient Register Dec 2020. In 16,365 individuals, low maternal education, but not household income, was associated with increased risk of Type 1 Diabetes; middle education RR 1.54, 95% CI 1.06, 2.23; P 0.02, low education RR 1.81, 95% CI 1.04, 3.18; P 0.04. Maternal education and household income was not associated with any other autoimmune disease and did not influence the age at diagnosis. Part of the increased risk of Type 1 Diabetes by lower maternal education was mediated by the indirect pathway of higher BMI and higher risk of Serious Life Events (SLE) at 5 years of age. The risk of developing Type 1 Diabetes associated to low maternal education might be reduced by decreasing BMI and SLE during childhood.