ALB and rheumatoid arthritis: The results of the 5 MR analyses were finally summarized in Figure 3, and the results of the IVW method study showed that there was a bidirectional causal relationship between serum ALB and RA, (IVW: ALB on RA, OR = 0.70 [0.52–0.93], P = .013; RA on ALB, OR = 0.95 [0.93–0.98], P < .001).