Factors associated with rapid spinal radiographic progression in patients with axial spondyloarthritis: A hospital-based retrospective cohort study with mSASSS scoring using deep learning model.

OBJECTIVE

To identify associated and protective factors of rapid spinal radiographic progression in axial spondyloarthritis (axSpA) using artificial intelligence (AI).

METHODS

We conducted a hospital-based retrospective cohort study involving 242 axSpA patients taken ≥2 lateral spine radiographs between 2002 and 2024. Spinal damage was assessed with modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) by a deep learning model. Each pair of consecutive radiographs defined an observational interval (total 379 intervals); annual mSASSS progression rate was calculated for each interval. Demographics, clinical features, baseline mSASSS, activity indices, cumulative dosage of prescriptions, and laboratory recordings were collected. Time-dependent generalized estimating equations (GEE) were applied to identify associated or protective factors of rapid spinal radiographic progression (ΔmSASSS/year >1), accounting for within-patient correlation.

RESULTS

For recorded intervals, mean mSASSS progression was 0.5/year; 26.7% of intervals showed progression >1/year. For enrolled patients, mean mSASSS progression was 0.6/year; 27.3% of intervals showed progression >1/year. Conditional multivariable GEE analysis revealed age at baseline mSASSS, especially ≥40 years, was independently associated with rapid mSASSS progression [adjusted odds ratio (aOR), 1.03; 95% confidence interval (CI), 1.003-1.06]. Higher cumulative dosage of non-steroidal anti-inflammatory drugs (NSAIDs) during the intervals was negatively associated with rapid mSASSS progression (aOR, 0.38; 95% CI, 0.19-0.75). Cumulative dosage of tumor necrosis factor inhibitors and secukinumab during the intervals was independent of rapid mSASSS progression.

CONCLUSIONS

Using AI-assisted mSASSS scoring, this retrospective cohort study identified older age at assessment as an associated factor and full-dose NSAIDs use as protective factor for rapid spinal radiographic progression.