Table 1.
Baseline characteristics and clinical features of CBP patients in the SPACE (n = 438) and DESIR cohorts (n = 647)
| Characteristic | SPACE n = 438 | DESIR n = 647 |
|---|---|---|
| Age, years | 31.3 (8.3) | 33.6 (8.6) |
| Symptom duration, months | 13.4 (7.4) | 18.1 (10.5) |
| Male | 165 (38) | 305 (47) |
| IBP | 286 (66) | 647 (100)* |
| Good response to NSAIDsa | 181/420 (43) | 515/643 (80) |
| Past history or current symptoms | ||
| Peripheral arthritis | 64 (15) | 363 (56) |
| Dactylitis | 24 (6) | 83 (13) |
| Enthesitis | 89 (20) | 312 (48) |
| AAU | 34 (8) | 51 (8) |
| IBD | 34 (8) | 23 (4) |
| Psoriasis | 51 (12) | 97 (15) |
| Elevated CRP (mg/L)/ESR (mm)b | 123 (28) | 254 (39) |
| HLA-B27 positive | 174/436 (40) | 376/646 (58) |
| Sacroiliitis, radiographyc | 48/434 (11) | 172 (27) |
| Sacroiliitis, MRIc | 135/431 (31) | 207/636 (33) |
| ASAS criteria for axSpA | 203 (46) | 410/634 (65) |
| Any positive family historyd | 185 (42) | 249 (39) |
| PFH of AS | 90 (21) | 127 (20) |
| PFH of AAU | 27 (6) | 29 (5) |
| PFH of ReA | 14 (3) | 6 (1) |
| PFH of IBD | 33 (8) | 32 (5) |
| PFH of Psoriasis | 83 (19) | 129 (20) |
| Total number of SpA diseases in first- or second-degree relatives | ||
| Number of patients with 1 disease | 135 (73) | 189 (76) |
| Number of patients with 2 diseases | 39 (21) | 47 (19) |
| Number of patients with ≥3 diseases | 11 (6) | 13 (5) |
Unless specified otherwise, results are presented as mean ± SD or number (%)
*Inclusion criterion
aBack pain not present anymore or is much better 24–48 hours after a full dose of NSAID
bValues greater than the upper limit of normal
cImaging based on local reading. of sacroiliac joints
dPresence in first- or second-degree relatives of any of the following: AS, AAU, ReA, IBD, or psoriasis
AAU acute anterior uveitis, AS ankylosing spondylitis, ASAS axSpA criteria, Assessment of Spondyloarthritis international Society criteria for axial Spondyloarthritis, CBP chronic back pain, CRP C-reactive protein, ESR erythrocyte sedimentation rate, HLA-B27 human leucocyte antigen B27, IBD inflammatory bowel disease, IBP inflammatory back pain, MRI magnetic resonance imaging, NSAID non-steroidal anti-inflammatory drug, PFH positive family history, ReA reactive arthritis, SpA spondyloarthritis