Psoriasis and imaging progression in early axial spondyloarthritis: results from a 48-month follow-up (Italian arm of SPACE study).

OBJECTIVES

To assess the influence of psoriasis on spinal/pelvic radiographic progression and MRI features in early-stage axial spondyloarthritis (axSpA).

METHODS

Analysis of baseline data from the Italian SPACE cohort, including patients with chronic back pain (CBP; duration ≥3 months and ≤2 years; onset <45 years) was performed. Patients underwent a diagnostic work-up, including MRI and X-rays of the sacroiliac joints (SIJ), to establish diagnosis of axSpA (Assessment of Spondyloarthritis International Society criteria). Clinical features, disease activity and functional indices, imaging were collected at baseline and yearly during 48 months. Spinal and SIJ X-rays and MRIs were scored by two readers following Spondyloarthritis Research Consortium of Canada score, Stoke Ankylosing Spondylitis Spinal Score System modified by Creemers and modified New York criteria. Characteristics of axSpA patients with/without psoriasis were compared over time with descriptive statistics; multivariate logistic regression model was constructed to assess predictors of spinal/pelvic radiographic progression.

RESULTS

Eighty-eight patients had axSpA (84.1% non-radiographic; 15.9% radiographic); 36.4% had psoriasis. Patients with psoriasis were older; less frequently had HLA-B27+ and radiographic sacroiliitis with unilateral/asymmetric pattern and more signs of spondylitis. Functional and disease activity indices decreased with slightly higher BASDAI and BASFI in axSpA with psoriasis. All patients showed slight spinal/pelvic radiographic progression. Patients without psoriasis showed increased sacroiliitis progression and low-grade spinal progression. More inflammatory corner lesions on cervical/thoracic MRI-spine were observed in patients with psoriasis. A significant downtrend of SPARCC SIJ/spine scores in all patients was found. Psoriasis was a predictor of increased spinal progression (odds ratio = 0.18; 95% CI: 0.04, 0.78).

CONCLUSIONS

Psoriasis was associated with distinct axSpA features, increased spinal radiographic progression and low-grade radiographic sacroiliitis.