Characteristics of the cohort with psoriatic arthritis
| DIP, distal interphalengeal; DMARD, disease-modifying antirheumatic drug; HAQ, Health Assessment Questionnaire; IQR, interquartile range; PASI, Psoriasis Area and Severity Index; MH, medical history; PsA, psoriatic arthritis. | |
| *Involved joints refer to tender, swollen or damaged joints. | |
| Characteristics of patients with PsA (n = 480) | |
| Female gender, n (%) | 275 (57) |
| Plaque psoriasis, n (%) | 393 (82) |
| Type I psoriasis (age at onset ⩽40 years), n (%) | 354 (74) |
| Type II psoriasis (age at onset >40 years), n (%) | 123 (26) |
| Median (IQR) age at onset of psoriasis (years) | 26 (15–42.5) |
| Median (IQR) age at onset of arthritis (years) | 36.5 (26–49) |
| Family history of | |
| Psoriasis, n (%) | 236 (49) |
| PsA, n (%) | 34 (7) |
| Nail involvement, n (%) | 391 (81) |
| Presence of rheumatoid factor, n (%) | 81 (17) |
| Ever used DMARD, n (%) | 389 (81) |
| MH of dysentery, n (%) | 20 (4) |
| MH conjunctivitis, n (%) | 156 (33) |
| MH uveitis, n (%) | 23 (5) |
| MH recurrent mouth ulcers, n (%) | 157 (33) |
| MH of sexually transmitted disease, n (%) | 12 (3) |
| Median (IQR) PASI | 6 (2.5–11.2) |
| Median (IQR) HAQ | 1.25 (0.25–1.875) |
| Median (IQR) duration of psoriasis (years) | 19 (9–33) |
| Median (IQR) duration of arthritis (years) | 10 (5–19) |
| Onset | |
| Psoriasis (>1 year) before arthritis, n (%) | 304 (63) |
| Arthritis (>1 year) before psoriasis, n (%) | 72 (15) |
| Psoriasis and arthritis at the same time (±1 year), n (%) | 104 (22) |
| Involved joint * | |
| Whole cohort, median (IQR) | 10 (4.5–21) |
| Presence of DIP involvement, n (%) | 310 (65) |
| Mono-involved joints, n (%) | 22 (5) |
| Oligo-involved joints (⩽4 joints), n (%) | 98 (20) |
| Poly-involved joints (⩾5 joints), n (%) | 360 (75) |
| Tender joint count | |
| Whole cohort, median (IQR) | 2 (0–6) |
| Swollen joint count | |
| Whole cohort, median (IQR) | 1 (0–4) |
| Damaged joints | |
| Whole cohort, median (IQR) | 6 (2–15) |
| DIP damaged, n (%) | 257 (54) |
| Mono-damaged, n (%) | 36 (8) |
| Oligo-damaged (⩽ 4 joints), n (%) | 132 (28) |
| Poly-damaged joints (⩾5 joints), n (%) | 272 (57) |