Background/Purpose: Differentiating between pain related to spondyloarthritis (in particular polyenthesitis) and pain related to fibromyalgia can be challenging, both in daily practice and in clinical trials. Some rheumatologists believe an “extreme” enthesitis score and/or pain/Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score may reflect a “fibromyalgia” disease. Additionally, depression is frequently observed in fibromyalgia patients; thus, an “extreme” enthesitis and/or pain/BASDAI score may correlate with an elevated depression score. The purpose of this post-hoc analysis was to evaluate patients with spondyloarthritis in order to: 1) estimate the percentage of patients with such “extreme” scores; 2) evaluate the relationship between “extreme” scores and depression; 3) evaluate the effect of baseline “extreme” scores on treatment outcome for etanercept and placebo.

Methods: Patients with non-radiographic axial spondyloarthritis participated in a randomized clinical trial and received double-blind etanercept 50 mg or placebo weekly. For this analysis, patients were divided into those who did vs. those who did not have extreme scores at baseline. Extreme baseline scores were defined as the highest quintile for enthesitis score (≥6), and/or scores ≥8 on 3 of 5 BASDAI items (morning stiffness duration was excluded). Depression was evaluated using the Hospital Anxiety and Depression Scale, depression subscale (HADS-D). Treatment outcome was the Assessment of SpondyloArthritis (ASAS) 40 response rate at week 12.

Results: Of the 213 patients at baseline, 35 (16%) met only enthesitis criteria, 31 (15%) met only BASDAI criteria, 12 (6%) met both criteria, and 135 (63%) met neither criteria. Patients with extreme enthesitis and/or BASDAI scores vs. those without were more likely to have moderate to severe depression at baseline: 20/68 (29%) vs. 10/118 (9%) of patients had HADS-D score >11 (P<0.001). For patients with vs. without extreme scores, no significant difference existed in week 12 ASAS40: etanercept 13/41 (32%) vs. 21/60 (35%); placebo 5/36 (14%) vs. 12/68 (18%). 

Conclusion: Extreme enthesitis and/or BASDAI scores correlated with depression at baseline, but did not have an effect on week 12 ASAS40 in either the etanercept or placebo treatment group.

---

« Back to 2014 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/evaluation-of-extreme-enthesitis-andor-patient-related-outcome-score-as-potential-surrogates-for-fibromyalgia-and-as-potential-confounding-factors-of-anti-tnf-response/