Axial spondyloarthritis is an inflammatory disease that mainly affects the spine and sacroiliac joints, but many patients may also have symptoms outside the spine. Psoriasis, a chronic skin condition, is common in people with spondyloarthritis, but it is not always clear whether these patients have a different type of spinal disease or whether they have more involvement of other joints and tendons.

In this study, we analyzed data from 740 patients included in the Latin American ESPALDA registry. Psoriasis was present in 12% of patients. Patients with psoriasis had more peripheral arthritis, more enthesitis, higher pain scores, and higher overall disease activity. However, psoriasis was not associated with more inflammation or structural damage in the spine or sacroiliac joints on MRI.

These findings suggest that patients with axial spondyloarthritis and psoriasis may have a disease pattern mainly driven by peripheral joint and tendon involvement, rather than by more severe axial damage. They may also represent, in some cases, patients with psoriatic arthritis and axial involvement. This highlights the importance of evaluating both spinal and peripheral symptoms when assessing and treating patients with psoriatic disease.