The Clinical Characteristics of Psoriatic Arthritis: A Cross-Sectional Study Based on the Psoriatic Arthritis Cohort of West China Hospital

INTRODUCTION: This study aims to describe the demographic, clinical, laboratory, and ultrasonic characteristics of patients with psoriatic arthritis (PsA) in the Psoriatic Arthritis cohort of West China Hospital. METHODS: In this cross-sectional study, we included patients diagnosed with PsA according to the Classification Criteria for Psoriatic Arthritis, collected their demographic information, medical histories, and treatments, evaluated all domains (skin and nail lesions, tenderness, swelling, enthesitis, dactylitis, and axial arthritis) related to PsA, and then performed descriptive statistical analyses of all data. RESULTS: A total of 275 patients with PsA were included in this study. The ratio of male to female patients was 2.16:1. Skin lesions preceded arthritis in 86.5% of these patients with PsA with a mean interval of 10.1 years. The metacarpophalangeal (MCP) joints, proximal interphalangeal (PIP) joints of fingers, and sacroiliac joints are the most commonly involved sites of tenderness, swelling, and the spine, respectively. Among all comorbidities, fatty liver has the highest incidence with 33.1%. Finally, we noted that the mean disease duration of PsA was 4.2 years, suggesting a delay in the diagnosis of PsA. CONCLUSION: Our study proposes that the prevalent population of PsA are male patients with psoriasis over 40 years of age who have a long disease course. For patients with PsA, MCP, PIP joints of fingers, and sacroiliac joints are the most frequently affected anatomical sites. With respect to comorbidities, the association between PsA and fatty liver and the underlying molecular mechanisms are worthy of further exploration.