N | Cohort 1 (n=407) | N | Cohort 2 (n=416) | |
---|---|---|---|---|
Age at symptom onset (years) | 407 | 53 (43–64) | 416 | 57 (48–69) |
Gender (female) | 407 | 250 (61%) | 416 | 269 (65%) |
Baseline visit | ||||
Symptom duration (months) | 407 | 5.4 (3.0–10.0) | 416 | 6.7 (4.5–11.4) |
RA (1987 ACR criteria) | 407 | 255 (62.7%) | 416 | 220 (52.9%) |
No of swollen joints | 407 | 7 (3–14) | 416 | 3 (1–7) |
No of tender joints | 407 | 7 (2–14) | 416 | 3 (0–8) |
CRP (mg/L) | 336 | 10 (2–27) | 363 | 12 (4–26) |
DAS28(3)CRP | 336 | 4.5 (3.5–5.5) | 363 | 3.7 (2.8–4.7) |
HAQ score | 398 | 1.0 (0.5–1.6) | 408 | 1.0 (0.5–1.8) |
RF (positive) | 368 | 160 (43.5%) | 371 | 155 (41.8%) |
ACPA (positive) | 288 | 130 (45.1%) | 341 | 136 (39.9%) |
SE (no of alleles) | ||||
0 | 351 | 115 (32.8%) | 371 | 135 (36.4%) |
1 | 170 (48.4%) | 178 (48.0%) | ||
2 | 66 (18.8%) | 58 (15.6%) | ||
Previous or current DMARD use | 407 | 142 (34%) | 416 | 269 (65%) |
Previous or current steroid use | 407 | 29 (7%) | 416 | 130 (31%) |
Smoking | ||||
Never smoked | 407 | 129 (31.7%) | 377 | 113 (30.0%) |
Ex-smoker | 162 (39.8%) | 166 (44.0%) | ||
Current smoker | 116 (28.5%) | 98 (26.0%) |
Patients in cohort 1 were recruited between 1990 and 1994 and patients in cohort 2 were recruited between 2000 and 2004. Values are median (IQR) for continuous variables and numbers (%) for categorical variables.
ACPA, anti-citrullinated protein antibody; ACR, American College of Rheumatology; CRP, C-reactive protein; DAS28(3)CRP, 28-joint disease activity score based on three components including CRP; DMARD, disease-modifying antirheumatic drug; HAQ, health assessment questionnaire; RA, rheumatoid arthritis; RF, rheumatoid factor; SE, shared epitope.