Table 2.
Axial clinical examination and radiographic characteristics in pPsA, fPsA, and fPsA/PSO cases
| pPsA | fPsA | fPsA/PSO | P1 | P2 | pPsA versus fPsA/PSO | fPsA versus fPsA/PSO | |
|---|---|---|---|---|---|---|---|
| OR (95% CI) | OR (95% CI) | ||||||
| HLA-B*27 presence, n (%) | 54 (37.2) | 39 (40.6) | 25 (45.5) | 0.289 | 0.563 | 0.712 (0.380–1.335) | 0.821 (0.421–1.603) |
| Axial symptoms, n (%) | |||||||
| Current | 59 (40.7) | 47 (49.0) | 24 (43.6) | 0.706 | 0.528 | 0.886 (0.473–1.660) | 1.239 (0.636–2.413) |
| Ever | 59 (40.7) | 46 (47.9) | 21 (38.2) | 0.747 | 0.247 | 1.111 (0.587–2.100) | 1.490 (0.758–2.927) |
| BMD, n (%) | 0.075 | 0.047 | 1.755 (0.931–3.308) | 1.954 (1.000–3.820)* | |||
| Osteopenia | 41 (28.3) | 29 (30.2) | 15 (27.3) | 0.880 (0.637–1.216) | 0.990 (0.667–1.469) | ||
| Osteoporosis | 26 (17.9) | 18 (18.8) | 4 (7.3) | 0.203 (0.134–0.306) *** | 0.211 (0.129–0.345)*** | ||
| Clinical examination indices | |||||||
| BASDAI, mean (SD) | 4.12 (0.82) | 3.74 (0.74) | 4.09 (0.93) | 0.716 | 0.031 | ||
| BASFI, mean (SD) | 3.81 (0.82) | 3.22 (0.76) | 3.69 (0.86) | 0.339 | 0.004 | ||
| ASDASCRP, mean (SD) | 3.19 (0.93) | 2.79 (0.83) | 3.32 (0.86) | 0.423 | 0.002 | ||
| Radiographic, n (%) | |||||||
| Sacroiliitis | 87 (60.0) | 51 (53.1) | 36 (65.5) | 0.479 | 0.140 | 0.792 (0.414–1.513) | 0.598 (0.301–1.187) |
| Spondylitis (cervical and/or lumbar) | 51 (35.2) | 31 (32.3) | 19 (34.5) | 0.934 | 0.777 | 1.028 (0.536–1.973) | 0.904 (0.448–1.822) |
| Sacroiliitis pattern, n (%) | |||||||
| Bilateral | 71 (49.0) | 39 (40.6) | 27 (49.1) | 0.545 | 0.332 | 1.077 (0.766–1.515) | 0.610 (0.295–1.262) |
| Morphology | |||||||
| Sacroiliac joint, n (%) | 0.822 | 0.037 | 0.938 (0.530–1.660) | 0.508 (0.272–0.949)* | |||
| Grade 1 | 5 (3.4) | 8 (8.3) | 2 (3.6) | 1.569 (1.134–2.170)* | 1.083 (0.732–1.602) | ||
| Grade 2 | 50 (34.5) | 35 (36.5) | 24 (43.6) | 1.356 (0.983–1.870) | 0.824 (0.556–1.220) | ||
| Grade 3 | 27 (18.6) | 8 (8.3) | 9 (16.4) | 0.261 (0.179–0.380)*** | 0.102 (0.058–0.181)*** | ||
| Grade 4 | 5 (3.4) | 0 | 1 (1.8) | 0.030 (0.013–0.070)*** | 0.005 (0.001–0.036)*** | ||
| Vertebral, n (%) | 0.973 | 0.266 | |||||
| Non-bridging syndesmophyte | 44 (30.3) | 30 (31.3) | 16 (29.1) | 0.974 (0.690–1.375) | 1.038 (0.500–2.156) | ||
| Bridging syndesmophyte | 7 (4.8) | 1 (1.0) | 3 (5.5) | 1.058 (0.524–2.137) | 0.185 (0.019–1.840) | ||
*P ≤ 0.05; **P ≤ 0.01; ***P ≤ 0.001
P1 P (pPsA vs. fPsA/PSO), P2 P (fPsA vs. fPsA/PSO), BASDAI Bath Ankylosing Spondylitis Disease Activity Index, ASDAS Ankylosing Spondylitis Disease Activity Score, BASFI Bath Ankylosing Spondylitis Functional Index