TNFSF13B and rheumatoid arthritis: Serum levels of soluble BAFF were slightly decreased in RA patients but were nonsignificantly different from healthy subjects in a bivariate analysis (median levels RA = 913.9 pg/ml vs. controls = 1128.0 pg/ml, p = 0.21) or after adjusting by age (p = 0.52) (Figure S1).