AB0888 EVALUATING THE PROGRESSION RATE FROM NON-RADIOGRAPHIC AXIAL SPONDYLOARTHRITIS TO RADIOGRAPHIC AXIAL SPONDYLOARTHRITIS AND THE CONTRIBUTING FACTORS
Authors: E. Erpek, E. Durak Ediboglu, İ. Kurut Aysin, E. Otman Akad, H. Cinakli, G. Alp, A. Özkan, H. Kocaayan, Ö. Yoğurtçu, H. İ. Y. Atli, M. Ozmen, D. Solmaz, S. Akar
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background and Objectives:</h3> <h3></h3> We aimed to examine the rates of progression and effective factors in patients diagnosed with non-radiographic axial spondyloarthritis (nr-AxSpA) progression to radiographic axial spondyloarthritis (r-AxSpA). <h3>Methods:</h3> Among the 695 patients followed in the Axial Spondyloarthritis (AxSpA) cohort, 209 individuals diagnosed with non-radiographic axial spondyloarthritis (nr-AxSpA) and with at least one follow-up pelvic AP radiograph were included in the study. 520 radiographs from 209 patients were evaluated by a single reader blinded to chronology. Demographic and clinical characteristics of the patients, baseline laboratory tests, baseline disease activity, function and quality of life scales, and treatment status were recorded. The progression rate from Nr-axSpA to r-axSpA was calculated during the mean follow-up period of 5.4±2.1; Factors that may have an impact on progression to r-axSpA were tested with "The Generalized Estimating Equations (GEE)" analysis method. <h3>Results:</h3> Among the 209 patients, progression from nr-axSpA to r-axSpA was observed in 57 individuals (27.3%) at the end of the follow-up period. The characteristics of patients with and without progression are presented in Table 1. In the second year, progression was observed in 29 out of 178 patients with imaging (16.29%), in the fifth year, 25 out of 119 patients with imaging (21.73%), and in the eighth year, 9 out of 37 patients with imaging (21.62%). Univariate Generalized Estimating Equations (GEE) analysis identified factors influencing progression from nr-axSpA to r-axSpA, including lower educational level (&lt;8 years), elevated C-reactive protein levels, poor spinal mobility assessed by baseline BASMI, and a positive family history according to ASAS criteria. In the model created for multivariate analysis, low educational level, family history, and elevated C-reactive protein level were found to be independent variables associated with the progression from nr-axSpA to r-axSpA (Table 2). <h3>Conclusion:</h3> The progression of non-radiographic axial spondyloarthritis (nr-axSpA) patients to radiographic axial spondyloarthritis (r-axSpA) appears to be associated with elevated C-reactive protein levels, consistent with findings from other studies. In contrast to previous research, this study uniquely identified the presence of a positive family history and lower educational level (&lt;8 years) as potential contributors to progression to r-axSpA. Additionally, the observed association between elevated BASMI (Bath Ankylosing Spondylitis Metrology Index) and progression to r-axSpA in this analysis may be considered a consequence rather than a cause of progression. <h3>REFERENCES:</h3> <b>NIL.</b> <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> <b>None declared.</b>