Table 3.
Baseline SpA featuresa
| Rheumatologist's clinical diagnosis of axial SpA and fulfillment of classification criteria | ||||||
|---|---|---|---|---|---|---|
| Yes by clinical diagnosis | No by clinical diagnosis | |||||
| AS(n = 101)b | Nonradiographic axial SpA(n = 157)c | Non–axial SpA(n = 61) | AS(n = 6)b | Nonradiographic axial SpA(n = 72)c | Non–axial SpA(n = 300) | |
| HLA–B27 positive | 49 (49) | 99 (63) | 8 (13) | 1 (17) | 64 (89) | 13 (4) |
| Number of patients with MRI results available | 19 | 150 | 61 | 1 | 71 | 300 |
| MRI evidence of sacroiliitisd | 16 (84) | 105 (70) | 0 (0) | 1 (100) | 9 (13) | 0 (0) |
| Radiographic evidence of sacroiliitise | 101 (100) | 9 (6)f | 0 (0) | 6 (100) | 1 (1)f | 0 (0) |
| Inflammatory back pain | 95 (94) | 149 (95) | 53 (87) | 6 (100) | 62 (86) | 292 (97) |
| Arthritis, past or present | 26 (26) | 52 (33) | 19 (31) | 2 (33) | 31 (43) | 60 (20) |
| Heel enthesitis, past or present | 27 (27) | 45 (29) | 20 (33) | 1 (17) | 22 (31) | 78 (26) |
| Dactylitis, past or present | 3 (3) | 11 (7) | 5 (8) | 0 | 2 (3) | 5 (2) |
| Anterior uveitis confirmed by an ophthalmologist | 12 (12) | 21 (13) | 2 (3) | 1 (17) | 13 (18) | 6 (2) |
| Psoriasis, past or present | 7 (7) | 12 (8) | 9 (15) | 1 (17) | 6 (8) | 33 (11) |
| Crohn's disease or ulcerative colitis,past or present | 8 (8) | 2 (1) | 3 (5) | 0 | 4 (6) | 13 (4) |
| Family history of SpAg | 18 (18) | 37 (24) | 8 (13) | 1 (17) | 28 (39) | 45 (15) |
| Good response to NSAIDsh | 51 (50) | 94 (60) | 26 (43) | 3 (50) | 40 (56) | 122 (41) |
| Elevated CRPi | 47 (47) | 57 (36) | 20 (33) | 2 (33) | 24 (33) | 82 (27) |
Except where indicated otherwise, values are the number (%) of patients. MRI = magnetic resonance imaging; CRP = C‐reactive protein.
Fulfilled the Assessment of SpondyloArthritis international Society (ASAS) criteria and modified New York criteria for ankylosing spondylitis (AS).
Fulfilled the ASAS criteria but not the modified New York criteria for AS.
Active inflammatory lesions of sacroiliac joints with definite bone marrow edema/osteitis, suggestive of sacroiliitis associated with spondyloarthritis (SpA).
Sacroiliitis of grade ≥2 bilaterally or grade 3–4 unilaterally, consistent with AS.
Includes patients with radiographic evidence of sacroiliitis fulfilling the radiologic criterion but none of the 3 clinical criteria of the modified New York criteria and who were, therefore, not captured in the subgroup of patients classified as having AS.
Presence in first‐ or second‐degree relative of any of the following: AS, psoriasis, anterior uveitis, reactive arthritis, or inflammatory bowel disease.
Back pain no longer present or much better 24–48 hours after a full dose of nonsteroidal antiinflammatory drugs (NSAIDs).
Values greater than the upper limit of normal for the local laboratory where testing was performed.