#209 : The Association Between Autoimmune Diseases and Gestational Diabetes Mellitus: A Mendelian Randomization Study

Background and Aims: As a common complication of pregnancy, gestational diabetes mellitus (GDM) may lead to a serious negative impact on pregnant women and their children. Autoimmune diseases are chronic pathologies triggered by abnormal responses of the human immune system that result in damage and disorders in the body. Recently, several studies have demonstrated that autoimmune diseases could be related to the risk of GDM. However, several other studies of this relationship have yielded conflicting results. We explored the causal relationship between autoimmune diseases and GDM risk through a two-sample Mendelian randomization (2SMR) study.

Method: We obtained exposure data for rheumatoid arthritis (RA) from a genome-wide association study (GWAS) pooled dataset, which consisted of 361,194 participants. We selected single-nucleotide polymorphisms (SNPs) that had a relationship with RA and were at a significance level of not only p < 5 × 10[Formula: see text] but also at a low linkage disequilibrium (LD) level (r² < 0.01). The results included 5,687 GDM cases and 117,892 controls. For detailed Methods, please see the Methods section in this article’s Online Repository at https://www.jacionline.org

Results: The results of inverse variance weight (IVW) analysis suggested a positive correlation between RA and GDM risk. In addition, no validity was observed in the statistical models for heterogeneity and pleiotropy. However, for multiple sclerosis (MS), no causal relationship between it and GDM risk was found in our study.

Conclusion: Our results suggest a strong casual association between RA and the risk of GDM. The results suggested the importance of enhanced antenatal care and early intervention among pregnant women with RA as well as clues for novel risk factors for GDM.