Psoriatic arthritis (PsA) is a chronic immunoinflammatory disease that, on the one hand, is considered as the most common comorbidity in psoriasis as part of systemic psoriatic disease, and, on the other, is classified as a clinical form of spondyloarthritis and lies at the interface of the basic problems of rheumatology and dermatology. The study of the evolution of psoriasis in relation to the development of PsA is a research priority area in rheumatology and dermatology, which is important for deciphering the nature of heterogeneity and the immunopathogenesis mechanisms of these diseases and for developing novel methods of personalized therapy at different stages of diseases.