Resumen:
Objective: To evaluate progression from nonradiographic (nr-) to radiographic axial spondyloarthritis (r-axSpA) over 5 years in patients with recently diagnosed (≤1 year) axSpA fulfilling the Assessment of SpondyloArthritis international Society (ASAS) classification criteria.
Methods: A prospsective, observational study (Patients with Axial Spondyloarthritis: Multi-Country Registry of Clinical Characteristics) was conducted in rheumatology practices in 29 countries. Baseline and follow-up radiographs of sacroiliac joints were centrally evaluated by three readers according to the grading system of the modified New York criteria for patients initially classified as nr-axSpA. Radiographic progression from nr-axSpA to r-axSpA was evaluated by Kaplan-Meier analysis. Cox proportional regression analyses for progression from nr-axSpA to r-axSpA were also conducted.
Results: Among 2,165 patients with axSpA, 1,612 (74%) were classified as having r-axSpA (1,050 [65%]) or nr-axSpA (562 [35%]) by central reading. Of 246 patients with nr-axSpA (mean [SD] symptom duration: 4.4 [6.2] years) who had at least one follow-up sacroiliac joint radiograph, progression from nr-axSpA to r-axSpA at any follow-up v...