Baseline patient characteristics (n=4377) according to anaemia status at inclusion
| Item | Anaemic (n=1054) | Non-anaemic (n=3323) | p Value |
|---|---|---|---|
| Age in years | 55 (±15) | 54 (±12) | 0.08 |
| Male gender (%) | 21 | 23 | 0.17 |
| DAS28ESR | 5.2 (±1.5) | 4.2 (±1.4) | <0.001 |
| cDAI | 28.2 (±14.2) | 21.2 (±16.3) | <0.001 |
| Disease duration in years | 6.7 (6.7) | 6.0 (6.4) | <0.001 |
| Erosion score (% of max) | 5 (1.5–24) | 3 (0.5–9) | <0.001 |
| Haemoglobin (g/dl) | 11.1±1.1 | 13.6±1.7 | <0.001 |
| RF positivity (%) | 80 | 76 | 0.03 |
| Subcutaneous nodules (%) | 31 | 28 | 0.009 |
| Vasculitis (%) | 6 | 4 | 0.005 |
| Methotrexate (%) | 41 | 45 | 0.03 |
| Other synthetic DMARDs (%) | 43 | 41 | 0.36 |
| Anti-TNF-α agents (%) | 5 | 6 | 0.26 |
| Corticosteroids (%) | 32 | 30 | 0.22 |
| Non-selective NSAIDs (%) | 34 | 30 | 0.004 |
| Coxibs (%) | 19 | 16 | 0.03 |
| Haematological comorbidities (%) | 19 | 4 | <0.001 |
| Renal comorbidities (%) | 2 | 2 | 0.27 |
| Gastrointestinal comorbidities (%) | 9 | 8 | 0.38 |
Parameters with Gaussian distribution are presented by the mean±SD, and non-normally distributed parameters by median and IQR. Anti-inflammatory treatment was often intensified after inclusion.
cDAI, clinical disease activity index15; DAS28ESR, disease activity score including the 28-joint count for tender and swollen joints and erythrocyte sedimentation rate; DMARDs, disease-modifying antirheumatic drugs; RF, rheumatoid factor; TNF, tumour necrosis factor.