Maternal autoimmune diseases during pregnancy tied to T1D risk in offspring

Children born to mothers with autoimmune diseases during pregnancy are at increased risk of type 1 diabetes (T1D), according to a study.

Researchers used national health registers in Sweden and identified children who were born between 2001 and 2014. They also obtained data on parental autoimmune diseases diagnosed before or during pregnancy.

The analysis included 1,455,645 included children (median age 15.3 years, 51.4 percent male), among whom 10,273 (0.71 percent) received a diagnosis of T1D over a median follow-up of 15.3 years.

In multivariable Cox proportional hazard regression models, maternal autoimmune disease during pregnancy was associated with a 57-percent increase in the risk of offspring T1D (adjusted hazard ratio [HR], 1.57, 95 percent confidence interval [CI], 1.46–1.68). Paternal autoimmune disease before childbirth showed a similar association with offspring T1D risk (adjusted HR, 1.51, 95 percent CI, 1.37–1.67).

No overall difference was observed in maternal-paternal comparisons (, but heterogeneity was observed across specific disease categories.

Overall analysis showed no significant difference between maternal and paternal autoimmune disease associations with offspring T1D risk (ratio of HR, 1.04, 95 percent CI, 0.92–1.17), although heterogeneity was observed across specific disease categories.

Children whose both parents had T1D had the highest risk of T1D, followed by those whose father had T1D and those whose mother had T1D.

The association between maternal autoimmune disease during pregnancy and T1D risk in offspring was attenuated but persisted in cousin analyses (HR, 1.27, 95 percent CI, 1.08–1.50).