Therefore, in our study, we utilized GWAS summary-level data from diverse large-scale cohorts and employed the MR method to determine the causal relationships between Klotho and AIDs (rheumatoid arthritis [RA], systemic lupus erythematosus [SLE], multiple sclerosis [MS], Crohn disease [CD], celiac disease [CeD], ulcerative colitis [UC], psoriasis [PsO], autoimmune hepatitis [AIH], primary sclerosing cholangitis [PSC], primary biliary cirrhosis [PBC], autoimmune thyroid disease [ATD], type 1 diabetes [T1D], pernicious anemia [PA]). Here, KL is linked to rheumatoid arthritis.