Table 1.
Characteristics of patients and healthy controls
| Healthy controls | RA | EIA | |
|---|---|---|---|
| Number of patients | 30 | 38 | 20 |
| Female sex, n (%) | 18 (60) | 27 (71) | 15 (75) |
| Age in years, mean (s.d.) | 51 (20) | 55 (16) | 51 (14) |
| Duration of symptoms in months, median (IQR) | 72 (24, 111) | 9 (5, 17) | |
| Rheumatoid factor +ve, n% | 28 (72) | 11 (55) | |
| ESR, mm/h, median (IQR) | 20 (11·5, 33) | 22 (12, 36) | |
| DAS28, mean (s.d.) | 4·6 (1·5) | 5·3 (1·3) | |
| C-reactive protein mg/l, mean (s.d.) | 14 (14·6) | 27·6 (60·0) | |
| Erosive disease, n (%) | 22 (58) | 11 (55) |
Patients with early inflammatory arthritis (EIA) were recruited from an early arthritis clinic, and patients with established rheumatoid arthritis (RA) were recruited from general rheumatology clinics. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and disease activity score 28 (DAS28) were measured on the day blood was drawn. Disease activity assessments were not performed in healthy subjects. IQR: interquartile ratio; s.d.: standard deviation.