Table 1.
Demographic and disease characteristics of patients included in the study. Results are shown as absolute numbers (percentages) or expressed as the mean ± standard deviation.
| Total N = 352 |
axSpA n = 287 (81%) |
axPsA n = 65 (19%) |
p-value | |
|---|---|---|---|---|
| Sex, male | 223 (63.4) | 180 (62.7) | 43 (66.2) | 0.7 |
| Age, years: | ||||
| At diagnosis | 35.9 ± 13.4 | 35.7 ± 13.7 | 36.9 ± 12.1 | 0.9 |
| At starting biologic therapy | 44.4 ± 13.2 | 44.1 ± 13.4 | 45.8 ± 11.6 | 0.3 |
| Disease duration before biologic therapy, years | 8.4 ± 9.2 | 7.9 ± 11.3 | 8.9 ± 9.0 | 0.7 |
| Current smoking habit | 158 (44.9) | 129 (44.9) | 29 (44.6) | 0.9 |
| HLA-B27 positive, n/N | 219/322 (67.8) | 204/281 (72.3) | 16/47 (34.1) | <0.001 |
| CRP, mg/dL | 12.4 ± 17.9 | 12.6 ± 18.9 | 11.1 ± 12.7 | 0.5 |
| Clinical involvement: | ||||
| Only axial | 170 (48.2) | 168 (58.5) | 14 (21.5) | <0.001 |
| Axial and peripheral | 182 (51.7) | 119 (41.5) | 51 (78.5) | |
| Radiographic sacroiliitis, mNY criteria, n/N | 227/341 (64.5) | 203/287 (70.7) | 24/54 (44.4) | <0.001 |
| Psoriasis | 74 (21.3) | 11 (4.2) | 63 (97) | <0.001 |
| Enthesitis, n/N | 85/205 (41.5) | 73/163 (44.8) | 12/42 (28.6) | 0.07 |
| Dactylitis | 10 (2.7) | 7 (2.4) | 3 (4.6) | 0.4 |
| IBD | 9 (2.6) | 8 (2.8) | 1 (1.5) | 0.7 |
| Uveitis | 46 (13.6) | 44 (15.3) | 2 (3.1) | 0.03 |
| ASDAS | 3.3 ± 0.9 | 3.3 ± 1.0 | 3.1 ± 1.0 | 0.1 |
| ASDAS ID | 8 (2.5) | 5 (2.0) | 3 (4.7) |
0.25 |
| ASDAS LDA | 24 (7.6) | 17 (6.8) | 7 (10.9) | |
| ASDAS HDA | 143 (45.4) | 112 (44.6) | 31 (48.4) | |
| ASDAS VHDA | 140 (44.4) | 117 (46.6) | 23 (35.9) | |
| BASDAI (0–10) | 5.9 ± 4.2 | 6.1 ± 4.5 | 5.23 ± 2.1 | 0.1 |
| PGA (0–100) | 63.2 ± 21.8 | 64.1 ± 21.5 | 58.8 ± 23.2 | 0.1 |
| PhyGA (0–100) | 39.1 ± 21.5 | 37.4 ± 13.7 | 44.4 ± 22.6 | 0.02 |
| PhyGA IGA | 2 (0.8) | 2 (1.0) | 0 |
0.13 |
| PhyGA LGA | 75 (28.6) | 58 (29.3) | 17 (26.6) | |
| PhyGA HGA | 115 (43.9) | 92 (46.5) | 23 (35.9) | |
| PhyGA VHGA | 70 (26.7) | 46 (23.2) | 24 (37.5) | |
| Concomitant therapy: | 193 (52.4) | 145 (50.5) | 48 (73.8) | 0.001 |
| Only MTX | 66 (20.7) | 36 (13.9) | 30 (46.2) | <0.001 |
| Only SFZ | 82 (25.6) | 73 (28.2) | 9 (13.8) | 0.03 |
| Prednisone use | 32 (9.5) | 20 (7.7) | 12 (20) | 0.004 |
ASDAS, Ankylosing Spondylitis Disease Activity Score; axPsA, axial psoriatic arthritis; axSpA, axial spondyloarthritis; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; CRP, C-reactive protein; HDA, high disease activity; HGA, High Global Assessment; IBD, inflammatory bowel disease; ID, inactive disease; IGA, Inactive Global Assessment; LDA, low disease activity; LGA, Low Global Assessment; mNY, modified New York; MTX, methotrexate; PGA, Patient Global Assessment; PhyGA, Physician Global Assessment; SFZ, sulfasalazine; VHDA, very high disease activity; VHGA, Very High Global Assessment.