Mendelian Randomization Research on the Relationship Between Rheumatoid Arthritis and Systemic Lupus Erythematosus and the Risk of Autistic Spectrum Disorder.

Objective: The purpose of this study was to examine whether there is a causal link between rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) and autism spectrum disorder (ASD). Methods: We used inverse variance weighted (IVW), weighted median, and MR-Egger regression methods to perform two-sample Mendelian randomization (MR) study using publicly available summary statistics datasets In addition, we employed genome-wide association studies (GWASs) for RA and SLE as exposure and an ASD GWAS as an outcome. Results: Thirty-three and 28 single-nucleotide polymorphisms from RA and SLE GWASs were selected as instrumental variables for ASD The IVW method revealed no evidence supporting a causal association between RA and SLE and risk for ASD (beta=-0077, standard error [SE]=0041, p=0062; beta=0014, SE=0021, p=0493) The weighted median approach yielded no evidence of any causal association between RA and SLE and risk for ASD (beta=-0071, SE=0058, p=0223; beta=0045, SE=0030, p=0130) MR-Egger analysis demonstrated no causal association between RA and SLE and risk for ASD (beta=-0062, SE=0079, p=0434; beta=0048, SE=0043, p=0273) The MR results calculated using IVW, the median weighted and the MR-Egger regression approaches were consistent. Conclusion: The findings of the MR analysis did not support a causal relationship between RA or SLE and the risk of ASD.