Table 1 Baseline characteristics of incident rheumatoid arthrits cases included in EIRA
All women (n = 1237) | ACPA negative | ACPA positive | |||
|---|---|---|---|---|---|
Aged 18–44 (n = 103) | Aged 45–70 (n = 331) | Aged 18–44 (n = 230) | Aged 45–70 (n = 573) | ||
Mean age, years (SD) | 51.5 (12.8) | 32.9 (7.0) | 58.8 (6.6) | 34.3 (7.4) | 57.6 (7.0) |
Parous, n (%) | 1009 (81.6) | 68 (66.0) | 292 (88.2) | 135 (58.7) | 514 (89.7) |
Nulliparous, n (%) | 228 (18.4) | 35 (34.0) | 39 (11.8) | 95 (41.3) | 59 (10.3) |
Mean time between last birth to symptom onset, years (SD) | 24.7 (12.1) | 6.8 (4.7) | 29.8 (8.1) | 7.2 (5.4) | 28.8 (9.2) |
Mean age at first birth, years (SD) | 24 (4.9) | 26 (5.3) | 24 (4.9) | 26 (4.6) | 24 (4.8) |
Mean number of children (SD) | 2.2 (0.9) | 1.9 (0.5) | 2.4 (0.9) | 2.3 (1.2) | 2.2 (1.0) |
Median DAS28 at inclusion, years (SD) | 5.4 (1.2) | 5.2 (1.1) | 5.6 (1.2) | 5.3 (1.1) | 5.4 (1.2) |
Median HAQ at inclusion (SD) | 1.0 (0.6) | 1.0 (0.5) | 1.1 (0.6) | 1.0 (0.6) | 1.1 (0.6) |
Ever smokers, n (%) | 823 (66.7) | 59 (57.3) | 202 (61.2) | 126 (55.0) | 436 (76.2) |
University degree, n (%) | 318 (25.7) | 31 (30.1) | 85 (25.7) | 82 (35.7) | 120 (21.0) |
Ever use of oral contraceptives before symptom onset, n (%) | 807 (65.6) | 89 (89.0) | 195 (59.1) | 185 (81.1) | 338 (59.1) |
Received DMARD at inclusion, n (%) | 1109 (87) | 91 (87) | 304 (90) | 190 (87) | 522 (89) |
Received prednisolone at inclusion, n (%) | 476 (37) | 32 (29) | 133 (38) | 70 (31) | 241 (40) |