EDN1 and rheumatoid arthritis: Therefore, the literature indicates that inflammation is a common feature of both RA and dementia, and this is confirmed by common inflammatory biomarkers found in both diseases (e.g., interleukin-6, interleukin-12, C-reactive protein, penxine 3, endotheline-1, resistin, and receptors for the end products of advanced glycation) [108].