Table 3.
Baseline disease activity measures in patients with axSpA at enrollment, stratified by enthesitis status
| Characteristic | Patients with axSpAa | P valueb | |
|---|---|---|---|
| With enthesitis (n = 121) | No enthesitis (n = 356) | ||
| ASDAS | 2.9 (0.9) | 2.5 (1.2) | <0.01 |
| BASDAI (0‐10) | 5.3 (2.2) | 4.1 (2.4) | <0.01 |
| BASFI (0‐10) | 4.5 (2.8) | 3.3 (2.7) | <0.01 |
| Tender joint count (0‐68) | 8.2 (10.8) | 1.3 (4.2) | <0.01 |
| Swollen joint count (0‐66) | 1.3 (3.3) | 0.5 (2.0) | <0.01 |
| Dactylitis, n (%) | 4 (3.3) | 7 (2.0) | 0.40 |
| Dactylitis (1‐20) | 2.0 (2.0) | 3.6 (3.9) | 0.35 |
| SPARCC Enthesitis Index (1‐16) | 3.9 (2.9) | 0 | … |
| Inflammatory back pain, n (%) | 78 (64.5) | 205 (57.6) | 0.18 |
| Lateral lumbar flexion (average of left and right), cm | 28.1 (21.1) | 21.5 (18.8) | 0.01 |
| CRP, mg/L | 6.9 (7.0) | 10.4 (24.1) | 0.32 |
| ESR, mm/h | 14.2 (16.4) | 15.5 (18.9) | 0.84 |
| Physician global assessment | 36.6 (21.9) | 23.5 (21.9) | <0.01 |
Abbreviation: ASDAS, Ankylosing Spondylitis Disease Activity Score; axSpA, axial spondyloarthritis; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; CRP, C‐reactive protein; ESR, erythrocyte sedimentation rate; SPARCC, Spondyloarthritis Research Consortium of Canada.
All values were calculated based on available data and are presented as mean (SD) unless otherwise stated and had less than 20% missing data except for ESR and CRP.
P value for comparison between patients with versus those without enthesitis. The Wilcoxon rank‐sum test was used for continuous variables, whereas the χ2 test was used for categorical variables. For variables where more than 20% of the cells had expected counts less than 5, the Fisher exact test was used.