Table 2.
Sociodemographic and laboratory characteristics of the PsSpA (n=118), AS (n=157) and pPsA (n=127) cases (numerical variables)
| PsSpA | AS | pPsA | AS versus PsSpA |
pPsA versus PsSpA |
|||
|---|---|---|---|---|---|---|---|
| Median (IQR) | Median (IQR) | Median (IQR) | Mean diff | Mean diff | |||
| Mean (SD) | Mean (SD) | Mean (SD) | (95% CI) | p Value | (95% CI) | p Value | |
| Age at (years) | |||||||
| Clinical assessment | 58.09 (11.42) | 53.44 (13.61) | 58.13 (11.71) | −4.63 (−7.68 to −1.58) | 0.003* | −0.03 (−2.95 to 2.88) | 0.98* |
| Arthritis onset | 31.27 (21.06, 46.24) | 20.00 (16.00, 26.00) | 37.98 (28.37, 46.32) | – | – | – | 0.01† |
| Arthritis diagnosis | 35.99 (27.27, 52.00) | 29.00 (23.00, 38.00) | 39.99 (29.70, 48.73) | – | – | – | 0.33† |
| Psoriasis onset | 31.50 (17.50, 41.50) | – | 27.00 (16.00, 14.00) | – | – | – | 0.68† |
| Psoriasis diagnosis | 33.00 (19.00, 43.00) | – | 30.00 (19.00, 46.00) | – | – | – | 0.20† |
| Disease duration at (years) | |||||||
| Recent axial radiograph | 15.50 (7.00, 26.00) | 19.00 (10.00, 29.00) | 13.00 (6.00, 23.00) | – | 0.13† | – | 0.41† |
| Clinical assessment | 18.00 (9.00, 27.00) | 22.00 (10.00, 31.00) | 15.00 (7.00, 26.00) | – | 0.13† | – | 0.34† |
| C reactive protein | 3 (2, 7) | 4 (1, 10) | 2 (0, 5) | 1.06 (0.99 to 1.12) | 0.07‡ | 0.79 (0.74 to 0.84) | <0.0001‡ |
| Body mass index (BMI) | 29.52 (5.16) | 29.92 (4.96) | 29.69 (5.36) | −1.60 (−2.21 to −0.84) | 0.01* | −0.18 (−0.62 to 0.51) | 0.81* |
*Two-tailed Student's t-test.
†Mann-Whitney U test.
‡Poisson regression (adjusted for: sex, age, disease duration, anti-TNF use ever, synthetic DMARD use ever, and BMI).
Anti-TNF, antitumour necrosis factor; AS, ankylosing spondylitis; DMARD, disease modifying antirheumatic drug; Mean diff, mean difference; pPsA, peripheral psoriatic arthritis; PsSpA, psoriatic spondyloarthropathy.