Comparison between psoriatic arthritis patients with and those without monoclonal gammopathy.
| Characteristic | Monoclonal Gammopathy, n = 35 | Controls, n = 326 | p |
|---|---|---|---|
| Age, yrs (± SD) | 61.3 (10.8) | 53.4 (13.2) | 0.001 |
| Sex, male, n (%) | 21 (60.0) | 223 (61.8) | 0.84 |
| White, n (%) | 29 (82.9) | 313 (86.9) | 0.51 |
| Duration of psoriasis, yrs (± SD) | 31.5 (16.9) | 25.7 (13.8) | 0.02 |
| Duration of PsA, yrs (± SD) | 22.0 (12.6) | 16.4 (11.1) | 0.006 |
| Swollen joint count (± SD) | 0.29 (0.71) | 0.32 (0.93) | 0.82 |
| Active joint count (± SD) | 6.7 (9.6) | 3.4 (6.3) | 0.07 |
| Clinically damaged joint count (± SD) | 16.0 (14.2) | 13.1 (13.8) | 0.32 |
| Dactylitis, n (%) | 3 (9.7) | 17 (5.0) | 0.27 |
| Enthesitis, n (%) | 3 (9.4) | 43 (12.4) | 0.62 |
| DMARD use, n (%) | 10 (28.6) | 192 (54.2) | 0.05 |
| Biologics use, n (%) | 14 (40.0) | 141 (40.2) | 0.98 |
| CRP, mg/dl (± SD) | 8.0 (6.3) | 6.6 (7.5) | 0.51 |
| Creatinine, μmol/l (± SD) | 88.1 (38.5) | 79.7 (24.3) | 0.22 |
| Leukocyte level, × 109/l (± SD) | 7.0 (6.4) | 7.2 (7.0) | 0.72 |
| ESR, mm/h (± SD) | 21.1 (19.7) | 11.7 (15.0) | 0.01 |
| Hemoglobin, g/l (± SD) | 131.6 (21.0) | 140.3 (15.4) | 0.02 |
| Gammaglobulin, mg/dl (± SD) | 10.2 (3.2) | 9.9 (5.6) | 0.68 |
| Rheumatoid factor-negative (%) | 17 (94.4) | 185 (96.9) | 0.65 |
| Functional comorbidity index (± SD) | 1.8 (1.3) | 1.4 (1.5) | 0.19 |
| Cancer ever, n (%) | 7 (20) | 44 (12.2) | 0.19 |
| Body mass index, kg/m2 (± SD) | 31.1 (8.9) | 29.5 (6.3) | 0.30 |
PsA: psoriatic arthritis: DMARD: disease-modifying antirheumatic drugs; CRP: C-reactive protein; ESR: erythrocyte sedimentation rate.