# Maternal Autoimmune Disease and Childhood‐Onset Type 1 Diabetes: A Nationwide Population‐Based Nested Case‐Control Study

## TL;DR

Children of mothers with autoimmune diseases, especially type 1 diabetes and thyroiditis, are at higher risk of developing type 1 diabetes.

## Contribution

This study identifies specific maternal autoimmune diseases as significant risk factors for childhood-onset type 1 diabetes.

## Key findings

- Maternal autoimmune diseases increase the risk of T1DM in offspring (aOR 1.95).
- Specifically, maternal T1DM, Hashimoto thyroiditis, and rheumatoid arthritis are strongly linked to childhood T1DM.

## Abstract

Type 1 diabetes mellitus (T1DM) is an autoimmune disease that damages insulin‐producing pancreatic cells, often appearing in childhood. Global incidence is rising at 2%–3% yearly. Its exact cause is unclear. Prenatal exposures and maternal autoimmune disorders have been reported as potential risk factors. This study aimed to explore how maternal autoimmune conditions might correlate with the onset of T1DM, employing a population‐focused approach.

This is a retrospective population‐based cohort study with a nested case‐control analysis. Primary data were derived from the Maternal and Child Health Database (MCHD) and the National Health Insurance Research Database (NHIRD). This study enrolled a total of 2,036,051 newborns born between 2004 and 2014. They were followed up until the end of 2020. A total of 1273 children under the age of 17 with T1DM were identified from 2004 to 2020. A 1:10 control group, matched by birth date and sex, was selected for comparison. T1DM patients were identified through the Catastrophic Illness Registry Database. Maternal autoimmune diseases were determined using the primary diagnosis codes for hospitalizations and outpatients’ visits.

After adjusting for cofactors, the offspring of mothers with an autoimmune disease had a higher risk of T1DM (adjusted odds ratio [aOR] 1.95, 95% confidence interval [CI]: 1.45–2.63, p  < 0.001). For individual autoimmune diseases, T1DM (aOR: 6.81, 95% CI: 2.30–20.16, p  < 0.001), Hashimoto thyroiditis (aOR: 3.75, 95% CI: 1.85–7.60, p  < 0.001), rheumatoid arthritis (aOR: 2.49, 95% CI: 1.08–5.77, p = 0.033), and Graves’ disease (aOR: 1.85, 95% CI: 1.14–2.99, p = 0.013) significantly increase the risk of developing T1DM in their children.

Offspring of mothers diagnosed with autoimmune disease, notably T1DM, autoimmune thyroiditis, and rheumatoid arthritis, may indeed have a heightened likelihood of developing T1DM. These findings underscore the importance of targeted screening programs for T1DM in children of affected mothers.