A cross-sectional study suggested that elevated syndecan-1 levels may be related to disease activity in rheumatoid arthritis.15 In another study involving patients with rheumatoid arthritis, 6 weeks of disease-modifying antirheumatic drugs (DMARDs) treatment was linked to a decrease in serum syndecan-1 levels, independent of inflammatory effects.16 This study also showed that tumor necrosis factor alpha (TNF-α) inhibitors did not produce the same effect on syndecan-1 as DMARDs16. Here, TNF is linked to rheumatoid arthritis.