Mendelian randomization analyses support causal relationships between systemic lupus erythematosus and brain imaging-derived phenotypes

Neuropsychiatric disorders in systemic lupus erythematosus (NPSLE) are often accompanied by alterations in brain structure and function. Subtle changes in brain structure also can be observed in non-NPSLE patients. MRI can be used as a non-invasive tool to determine nervous system involvement in SLE. However, the causal relationship between SLE and brain MRI remains unclear. We designed two-sample MR analyses to identify brain IDPs associated with SLE. The GWAS summary data of 3,935 IDPs from the UK Biobank were used as outcomes in MR analyses. There were 25 statistically significant causal relationships between SLE and brain IDPs, in which the several cortical area, anterior corona radiata, and posterior limb of internal capsule were included. These results may suggest the pathogenesis of neuropsychiatric symptoms in patients with SLE. The findings revealed strong genetic evidence for causal links between SLE and neuroimaging phenotypes. Our results provide a promising method for the daily assessment and monitoring of SLE patients.