An estimated 10% of patients with axial spondyloarthritis (axSpA) also present with psoriasis. While it is believed that a phenotype of the disease is responsible for this association, such a relationship has yet to be investigated. This study explored the correlation between clinical phenotype and radiographic progression and skin psoriasis in patients with axSpA. The findings were presented at the ACR/ARP Annual Meeting.
A total of 210 axSpA patients were included, 155 of whom had radiographic and 95 had non-radiographic axSpA. Two readers scored radiographs of the spine and sacroiliac joints per the modified Stoke Ankylosing Spondylitis Spinal Score and the grading system of the modified New York criteria. Multivariable regression analysis was employed to assess how psoriasis impacted radiographic progression. A total of 28 patients (13.3%) had axSpA and skin psoriasis.
Patients with a dual diagnosis were less frequently human leukocyte antigen-B27-positive; more likely to be treated with disease-modifying antirheumatic drugs; and had higher anamnestic prevalence of peripheral arthritis (n=16; 57.1% vs. n=58; 31.9%; P=0.01), higher disease activity (Bath Ankylosing Spondylitis Disease Activity Index 5.0±2.2 vs. 3.8±2.1; P=0.01), and worse physical function (Bath Ankylosing Spondylitis Functional Index 3.8±2.3 vs. 2.8±2.3; P=0.02).
In adjusted multivariable regression analysis, psoriasis was not significantly associated with radiographic progression in the spine (odds ratio [OR], 2.93; 95% confidence interval [CI], 0.81-10.58) or sacroiliac joints (OR, 1.98; 95% CI, 0.72-5.43). In conclusion, the researchers stated, “Presence of skin psoriasis in patients with axSpA was associated with HLA-B27 negativity, peripheral arthritis, higher disease activity, and worse functional status and did not impact the radiographic progression in axSpA.”