Comparative Disease Burden in Patients with Rheumatoid Arthritis, Psoriatic Arthritis, or Axial Spondyloarthritis: Data from Two Corrona Registries

INTRODUCTION: Rheumatoid arthritis (RA), psoriatic arthritis (PsA), and axial spondyloarthritis (axSpA) are three common inflammatory rheumatic diseases that can lead to deformities and joint destruction. Few studies have compared disease burden across patients with these diseases. The objective of this study was to compare disease burden in patients with RA, PsA, or axSpA in routine US clinical practice. METHODS: This study included adults with RA, PsA, or axSpA enrolled in the Corrona RA and PsA/SpA registries between March 2013 and March 2018. Patient and clinical characteristics at enrollment were compared between patients with RA vs. PsA and RA vs. axSpA using t tests or Wilcoxon rank-sum tests for continuous variables and χ(2) or Fisher’s exact tests for categorical variables. RESULTS: A total of 11,350 patients with RA, 2003 with PsA, and 495 with axSpA were included. Patients with RA had shorter mean symptom and disease duration (9.4 and 7.6 years, respectively) than those with PsA (11.2 and 8.4 years) or axSpA (16.7 and 9.8 years). Patients with PsA had lower mean physician global assessment (18.6 vs. 27.3), higher patient global assessment (43.2 vs. 36.9), comparable pain (38.9 vs. 39.5), and lower fatigue (41.1 vs. 43.4) scores than those with RA. Patients with axSpA had comparable mean physician global assessment (25.5 vs. 27.3) and higher patient global assessment (50.2 vs. 36.9), pain (46.1 vs. 39.5), and fatigue (48.3 vs. 43.4) scores than those with RA. CONCLUSIONS: Disease burden in patients with PsA or axSpA was comparable to or greater than that in patients with RA on the basis of common patient-reported outcome measures but appeared lower when assessed using RA disease activity measures, suggesting that disease-specific approaches to care are needed to optimize disease management. FUNDING: This study was sponsored by Corrona, LLC, and financial support was provided by Novartis. The Rapid Service Fee was funded by Novartis. PLAIN LANGUAGE SUMMARY: Plain language summary available for this article.