Axial spondyloarthritis treatment patterns, clinical characteristics and patient-reported outcome collection in US rheumatology practices.

Objectives: To investigate real-world treatment patterns, patient-reported outcome (PRO) collection practices and clinical outcomes among patients newly diagnosed with axial spondyloarthritis (axSpA) in a major US rheumatology network. Methods: Patients diagnosed with axSpA between 1 January 2016 and 7 November 2022 were identified in the United Rheumatology Normalized Integrated Community Evidence clinical data repository. Patient demographic and clinical characteristics were assessed for the 12 months before the first diagnosis (index date). Treatment patterns, PRO collection and clinical outcomes were assessed for the 12 months after diagnosis. Baseline characteristics and study outcomes are reported using descriptive statistics. Cumulative incidence of post-index clinical events is also reported. Results: Overall, 2641 patients newly diagnosed with axSpA were included. Most (87%) initiated axSpA medications within 1 year of diagnosis and 73% initiated treatment within 1 month. Biologics were prescribed as first-line therapy, alone or in combination, in 47%. Approximately half (52%) received one or more PRO assessment; most common were the Routine Assessment of Patient Index Data 3 (45%) and BASDAI (16%). PRO collection frequency met guidelines (two or more assessments in 12 months) in 38%. axSpA-related clinical events occurred in 19% of patients within 1 year of diagnosis. Conclusion: Patients recently diagnosed with axSpA often initiated a biologic-containing treatment regimen as first-line therapy, contributing to improved symptom management compared with those without biologic treatment. More than half of patients did not receive guideline-recommended PRO assessments, highlighting the opportunity for increased symptom monitoring to guide clinical decision-making.