Clinical and serological parameters in patients with RA stratified according to the IL-22 serum level at baseline*
| ‘IL-22 normal’ (n=25)† | ‘IL-22 high’ (n=24)‡ | p Value§ | |
|---|---|---|---|
| IL-22 (pg/ml) | 4.3±1.4 | 26.2±16.1 | <0.0001 |
| Age (years) | 54.7±11.1 | 51.3±13.8 | NS |
| Female/male (n) | 20/5 | 17/7 | NS |
| Disease duration (months) | 4.3±4.2 | 3.9±3.2 | NS |
| NSAID use (%) | 72.0 | 75.0 | NS |
| Smoking habit (%) | 44.0 | 62.5 | NS |
| RF positive (%) | 64.0 | 87.5 | NS |
| Anti-CCP positive (%) | 60.0 | 79.2 | NS |
| DAS28 | 4.5±1.3 | 4.7±1.2 | NS |
| TJC (n) | 6.2±5.2 | 6.7±4.5 | NS |
| SJC (n) | 5.6±5.0 | 5.9±4.3 | NS |
| CRP (mg/dl) | 2.4±3.6 | 2.4±4.1 | NS |
| ESR (mm/h) | 31.8±33.0 | 31.3±33.7 | NS |
| TNF (pg/ml) | 0.2±1.0 | 0.5±1.9 | NS |
| IL-17 (pg/ml) | 2.8±3.9 | 8.7±13.9 | <0.05 |
↵* Data are shown as mean±SD or absolute numbers.
↵† Patients with RA characterised by a normal IL-22 serum level (<7.5 pg/ml).
↵‡ Patients with RA characterised by a raised IL-22 serum level (>7.5 pg/ml).
↵§ p Values were calculated between the ‘IL-22 normal’ and ‘IL-22 high’ group by Mann–Whitney test or where applicable by Fisher's exact test.
anti-CCP, anti-cyclic citrullinated peptides; CRP, C-reactive protein; DAS28, Disease Activity Score in 28 joints; ESR, erythrocyte sedimentation rate; IL, interleukin; NSAIDs, non-steroidal anti-inflammatory drugs; RA, rheumatoid arthritis; RF, rheumatoid factor; SJC, swollen joint count; TJC, tender joint count; TNF, tumour necrosis factor.