IL17A and Alzheimer disease: It is currently unknown whether PsA with and without atopy, especially AD, will respond differently to biologics as well as to targeted synthetic disease-modifying anti-rheumatic drugs (tsDMARDs), such as Janus kinase (JAK) inhibitors; however, the intervention of specific proinflammatory cytokines (TNF α vs. IL-17 axis vs. IL-12/23 axis) in patients with AD, psoriasis, and PsA is able to promote different effects in response to different biologics, raising the question that AD might be a factor guiding biologic drug selection in patients with PsA and atopy.