Demographic data of the study group.
| Characteristic | Psoriatic Arthritis, mean (SD) | Control Group, n = 115, mean (SD) |
|---|---|---|
| Age, yrs (n = 456) | 57.4 (13.2) | 65 ± 14.1 |
| Age at onset of arthritis, yrs (n = 456) | 39.5 (13.8) | 56.8 ± 14.4 |
| Age at onset of psoriasis, yrs (n = 456) | 30.3 (15.4) | NA |
| Female, % | 53.1 | 73 |
| Rheumatoid factor-positive, % (n = 416) | 2.9 | 64 |
| Cyclic citrullinated antibody-positive, % (n = 363) | 1.3 | 43 |
| Phenotype, % (n = 316) | ||
| Distal interphalangeal (DIP) | 0.3 | |
| DIP and polyarthritis | 0.3 | |
| Monoarthritis | 1.7 | |
| Mutilans | 1.9 | |
| Oligoarthritis | 22 | |
| Oligoarthritis and spondyloarthritis | 3.9 | |
| Polyarthritis | 59.4 | |
| Polyarthritis and spondyloarthritis | 8.5 | |
| Spondyloarthritis | 1.9 |