Baseline data
| All patients n=824 | Patients with no courses of antibiotics* n=219 | Patients with >1 courses of antibiotics but no infection-related admissions* n=530 | Patients with ≥1 infection-related admissions* n=75 | |
| Age (years)† | 59.1 (13.7) | 58.1 (12.9) | 59.1 (13.9) | 62.0 (14.7) |
| Sex | ||||
| Male | 299 (36.3) | 86 (39.3) | 177 (33.4) | 36 (48.0) |
| Female | 525 (63.7) | 133 (60.7) | 353 (66.6) | 39 (52.0) |
| Smoking status | ||||
| Current or previous | 505 (61.4) | 123 (56.4) | 334 (63.1) | 48 (64.0) |
| Never smoked | 317 (38.6) | 95 (43.6) | 195 (36.9) | 27 (36.0) |
| (Missing) | 2 | 1 | 1 | 0 |
| Symptom duration (days)‡ | 131 (82–197) | 132 (92.5–198) | 131 (80–197.8) | 126 (73–185) |
| DAS28-CRP† | 4.8 (1.3) | 4.7 (1.4) | 4.8 (1.3) | 5.1 (1.3) |
| (Missing) | 55 | 15 | 33 | 7 |
| HAQ score† (0–3) | 1.2 (0.8) | 1.1 (0.8) | 1.3 (0.8) | 1.4 (0.8) |
| (Missing) | 4 | 2 | 2 | 0 |
| CCP (% positive) | 412 (61.3) | 108 (60.0) | 270 (61.4) | 34 (65.4) |
| (Missing) | 152 | 39 | 90 | 23 |
| RF (% positive) | 289 (58.3) | 74 (56.5) | 193 (59.8) | 22 (52.4) |
| (Missing) | 328 | 88 | 207 | 33 |
Data are n (%) unless otherwise stated.
*At any stage during the pre-RA or early arthritis stage.
†Mean (SD).
‡Median (IQR).
CCP, anti-cyclic citrullinated peptide antibodies; DAS28-CRP, 28 Joint Count Disease Activity Score; HAQ, Health Assessment Questionnaire; RA, rheumatoid arthritis ; RF, rheumatoid factor.