Baseline characteristics of the 379 patients, 208 with and 171 without antibodies to cyclic citrullinated peptides (anti-CCP)
| Valid values | All patients | Patients with anti-CCP | Difference† (p value) | ||
|---|---|---|---|---|---|
| Negative | Positive | ||||
| Values are median (25th to 75th centile) or n (%). | |||||
| †Upper limit of expected number of false significances = 0.26. | |||||
| DAS28, 28 joint disease activity score; ESR, erythrocyte sedimentation rate; HAQ, health assessment questionnaire; VAS, visual analogue scale. | |||||
| Age (years) | 379 | 55 (45 to 67) | 55 (41 to 71) | 55 (46 to 65) | 0.51 |
| Sex (female) | 379 | 247 (65%) | 115 (67%) | 132 (64%) | 0.44 |
| Disease duration (months) | 379 | 6 (4 to 8) | 6 (3 to 8) | 6 (4 to 9) | 0.36 |
| Smoking status (current or previous smoker) | 379 | 226 (60%) | 88 (52%) | 138 (66%) | 0.003 |
| Rheumatoid factor positive | 373 | 229 (61%) | 42 (25%) | 187 (91%) | 0.0005 |
| HLADRB1*04 present | 185 | 97 (52%) | 34 (38%) | 63 (66%) | 0.0005 |
| HAQ score (0–3) | 363 | 0.90 (0.50 to 1.38) | 0.95 (0.50 to 1.36) | 0.90 (0.40 to 1.38) | 0.913 |
| Pain VAS (0–100 mm) | 366 | 44 (25 to 66) | 40 (25 to 60) | 46 (25 to 67) | 0.36 |
| C reactive protein (mg/l) | 364 | 19 (6 to 43) | 10 (4 to 35) | 23 (10 to 52) | 0.0005 |
| ESR (mm/h) | 378 | 29 (14 to 50) | 22 (9 to 39) | 36 (21 to 56) | 0.0005 |
| DAS28 (0–10) | 371 | 5.10 (4.22 to 5.85) | 4.98 (4.15 to 5.74 | 5.30 (4.29 to 6.10) | 0.046 |
| Larsen score (0–200) | 342 | 4 (0 to 10) | 2 (0 to 10) | 5 (0 to 11) | 0.008 |