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Updated: May 28, 2026

Du-Moxibustion in a Mouse Model of Ankylosing Spondylitis
Published on: October 27, 2023
Development of new syndesmophytes and bridges in ankylosing spondylitis and their predictors: a longitudinal study
Astrid van Tubergen1, Sofia Ramiro, Désirée van der Heijde
1Department of Medicine, Division of Rheumatology, Maastricht University Medical Center, The Netherlands. a.van.tubergen@mumc.nl
Background:
Structural damage of the spine in ankylosing spondylitis (AS) is associated with worse physical function and impaired spinal mobility. Knowledge about predictors of new syndesmophyte formation is limited.
Objectives:
To assess the development of new syndesmophytes at the level of individual vertebral bodies and to assess predictors for this development.
Methods:
Clinical and radiological data from 132 patients from the Outcome in Ankylosing Spondylitis International Study for whom complete sets of radiographs were available at baseline and at 2- and 4-year follow-up were used. Univariable and multivariable logistic regression analyses were performed to identify predictors associated with development of new syndesmophytes within 4 years.
Results:
At baseline, 81 (61%) patients had syndesmophytes. New syndesmophytes developed in 44 (33%) patients within 2 years and in 63 (48%) patients within 4 years. The RR of developing new syndesmophytes was 5.0 (95% CI 2.5 to 10.2) at 4 years in patients with existing syndesmophytes as compared with patients without. In the univariable analysis, older age, worse functional status, male gender, erythrocyte sedimentation rate and existing syndesmophytes were associated with development of new syndesmophytes at 4 years. In the multivariable logistic regression analysis, only the presence of existing syndesmophytes was a significant predictor (OR 18.72, 95% CI 6.44 to 54.42). When existing syndesmophytes were taken out from the model, age (OR 1.07, 95% CI 1.03 to 1.11) and male gender (OR 3.98, 95% CI 1.47 to 10.77) were statistically significant contributors.
Conclusion:
In AS, patients with existing syndesmophytes are prone to develop new syndesmophytes over time.
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