Key clinical point: Axial involvement in psoriatic arthritis (axPsA) is a unique phenotype with characteristics lying between axial spondyloarthritis and pure peripheral PsA. Male gender, elevated C-reactive protein (CRP), and absence of psoriasis were associated with axPsA.
Major finding: Axial involvement was observed in 35.5% of patients with PsA, and they were thus classified as axPsA. Being male (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.09-2.61), having elevated CRP (OR, 2.87; 95% CI, 1.80-4.60), and absence of psoriasis (OR, 0.33; 95% CI, 0.15-0.72) were independently associated with axPsA.
Study details: The data come from an observational, cross-sectional ASAS-perSpA study of 3,684 patients with axial spondyloarthritis or PsA.
Disclosures: The ASAS-PerSpA study was funded by Pfizer, Lilly, AbbVie, Novartis, UCB, Janssen, and Merck. The authors including the lead author reported receiving consulting fees, speaking fees, and/or honoraria from various sources including AbbVie. Three authors reported no conflicts of interest.
Source: Benavent D et al. Semin Arthritis Rheum. 2021 May 5 . doi: 10.1016/j.semarthrit.2021.04.018.