CLINICAL AND IMAGING-BASED CHARACTERIZATION OF A PROSPECTIVE COHORT OF PATIENTS WITH AXIAL PSORIATIC ARTHRITIS (AXIAL PSA). GESPIC-AXIAL PSA: RESULTS OF AN INTERIM ANALYSIS
Authors: Käding H et al.
Axial involvement in psoriatic arthritis has been of interest more recently and has been identified as an important disease domain. The observational and longitudinal German GESPIC Cohort was used to prospectively evaluate the clinical and imaging patterns of patients with axial PsA. Conventional radiographs and MRI scans of the spine and the sacroiliacal joint were performed at baseline and after 2 years. Patients were seen every 6 months. In this interim analysis, baseline data is presented.
Between 8/2019 and 12/2021, 85 axial PsA patients were included with a mean age of 45.2 + 12.9 years, 55.3% female. 45.9% were HLA-B27 positive, and peripheral involvement was observed in 50.6% of patients. An inflammatory type of backpain was noted in 75% of patients. 44.9% fulfilled the modified New York Criteria. MRI inflammation of the IS joints was demonstrated in 55% and structural changes evident in 73.8%. Interestingly, involvement of the spine without IS joint inflammation was observed in 18.8% of patients.
Based on retrospective and cross-sectional analyses, axial involvement in psoriatic arthritis occurs in up to 34% of patients but it is still unclear, whether the features of axial involvement in PsA are similar to classical axSpA or not. The data presented here are based on an interim analysis of the GESPIC cohort and suggest some distinct differences with regard to clinical and radiomorphologic features of axial involvement in PsA compared to classical axSpA. Patients with axial PsA are less frequently HLA-B27 positive and more frequently female. Nearly 20% of the patients showed an isolated spinal involvement.
These differences suggest that a modified diagnostic approach may be warranted in patients with PsA who report on inflammatory backpain.