FRI0199 Five-Year Follow-Up of Radiographic Sacroiliitis: Progression as Well as Improvement?. (9th June 2015)

• Record Type: Journal Article
• Authors: Sepriano, A.R.; Rudwaleit, M.; Sieper, J.; van den Berg, R.; Landewé, R.; van der Heijde, D.
• Is Part Of: Annals of the rheumatic diseases. Volume 74(2015)Supplement 2
• Page Start: 496
• Page End: 497
• Publication Date: 2015-06-09
• Subjects: Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/annrheumdis-2015-eular.4169
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Background: Detecting sacroiliitis on plain pelvic X-rays is known to be difficult, resulting in large variability regarding presence/absence of radiographic sacroiliitis. In addition, the number of patients with radiographic sacroiliitis in a cohort of patients with axial SpA can be expected to (slightly) increase or remain stable over time but certainly not decrease. Objectives: We have investigated the change of pelvic X-ray abnormalities over time in the Assessment of SpondyloArthritis international Society (ASAS) validation cohort. Methods: In the ASAS study, 975 patients with either chronic back pain (>3 months) of unknown origin beginning <45 years of age or undiagnosed peripheral arthritis, and/or enthesitis, and/or dactylitis were assessed at baseline. From these, 565 patients were followed and reassessed at follow-up [mean follow-up time 4.44 years (SD: 1.01)]. Patients with radiographs of the pelvis (X-SI) available at baseline and follow-up were included in this analysis (n=357). Readings were performed locally at both time points, either by the same or by a different reader. Positive cases were defined as definite radiographic sacroiliitis (grade ≥2 bilaterally or grade 3–4 unilaterally) according to the modified New York criteria (mNY). Results: In total, 357 patients with follow-up visit had also baseline radiographs available. The proportion of patients fulfilling the radiographic mNY at baseline was 17.4% (62/357), whereas at follow-up 22.4% (80/357) of the patients fulfilled these criteria (table ). However, more than half of the patients (36/62; 58.1%) with positive baseline X-SI were graded negative at follow-up. Moreover, 54/295 (18.3%) became positive at follow-up. However, given the percentage of the patients "becoming negative", it is hard to decide what the real rate of progression is. Conclusions: Our results confirm that radiographic sacroiliitis, defined by the mNY, is a poorly reliable method. Consequently, this method is difficult to use as an outcome measure to define progression in a cohort of patients, with and without treatment, although paired reading may improve the result. Disclosure of Interest: None declared