ACR 2016 News in Rheumatology: Psoriatic Arthritis

ACR 2016. Abstract 1657. Soluble Biomarkers May Differentiate Psoriatic Arthritis from Osteoarthritis

Vinod Chandran et al.

Results: Univariate analyses revealed the following markers significantly differed across groups (p<0.001): COMP, hyaluronan; resistin, HGF, insulin, leptin; CRP, IL -6, -8, TNF-α, MCP-1, NGF. When comparing PsA to OA controlling for age and sex, the following markers significantly differed (p<0.001): COMP ; resistin, HGF, insulin; IL-6, -8, TNF-α, MCP-1, NGF; and Adipsin (p<0.03). Multivariate analysis demonstrated that COMP (OR 1.24, 95% CI 1.06, 1.46), resistin (OR 1.26, 95% CI 1.07, 1.48), MCP-1 (OR 1.28, 95% CI 1.01, 1.48) and NGF (OR <0.001, 95% CI <0.001, 0.25) were independently associated with PsA vs. OA. The area under the ROC curve (AUROC) for this model was 0.99. Internal cross-validation of the model consistently identified MCP-1 as a PsA marker. Further validation of the model including COMP, resistin, MCP-1 and NGF in an independent sample set showed an AUROC of 0.98 (Figure).  

Conclusion: A panel of 4 biomarkers (COMP, resistin, MCP-1, NGF) may distinguish PsA from OA. Clinical utility of these markers will need to be determined in prospective studies.              

CARE Faculty Perspective: One of the challenges in diagnosing psoriatic arthritis is differentiating it from osteoarthritis, especially erosive hand osteoarthritis. This early proof-of-concept study indicates that a panel of soluble biomarkers may be useful in making the diagnosis. These markers will now need to be further verified and validated as well as clinical utility and cost-effectiveness determined.