A dysregulated production of cytokines—particularly interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-17 (IL-17)—could be proposed as a unifying common feature between PsA, depression, and ED, as it plays a key role in the pathogenesis of psoriatic diseases and seems to be associated to mood disorders and impaired endothelial function in non-psoriatic cohorts (13, 14). This evidence concerns the gene IL17A and major depressive disorder.