To test the impact of inflammation on MRI‐structural changes occurring in the sacroiliac joints (SIJ) and the spine. Patients with early axSpA from the DESIR cohort were included. MRIs of the SIJ (MRI‐SIJ) and spine (MRI‐spine), obtained at baseline, 2 and 5 years, were scored by three central readers. Inflammation and structural damage on MRI‐SIJ/MRI‐spine were defined by the agreement of ≥2 of 3 readers (binary outcomes) and by an average of 3 readers (continuous outcomes). The inflammation (MRI‐SIJ/MRI‐spine) effect on damage (MRI‐SIJ/MRI‐spine, respectively) was evaluated in two models:
1) Baseline prediction model: effect of baseline inflammation on damage assessed at 5‐year; and
2) Longitudinal model: the effect of inflammation on structural damage assessed during five years.
Two hundred two patients were included. Both the presence of bone marrow edema (BME) on MRI‐SIJ and MRI‐spine at baseline were predictive of 5‐year damage (≥3 fatty lesions) on MRI‐SIJ [OR=4.2 (95% CI: 2.4; 7.3)] and MRI‐spine [OR=10.7 (95% CI: 2.4; 49.0)], respectively, when adjusted for CRP. The association was also confirmed in longitudinal models (when adjusted for ASDAS) both in the SIJ [OR=5.1 (95% CI: 2.7; 9.6)] and spine [OR=15.6 (95% CI: 4.8; 50.3)]. Analysis of other structural outcomes (i.e., erosions) on MRI‐SIJ yielded similar results. In the spine, a significant association was found for fatty lesions but not for erosions and bone spurs, which infrequently occurred over time.
We found a predictive and longitudinal association between MRI‐inflammation and several types of MRI‐structural damage in patients with early axSpA, which adds to the proof for a causal relationship.
Ref: https://onlinelibrary.wiley.com/doi/10.1002/acr.24449
