Table 4.
OR with 95% CI of developing ACPA positive RA and ACPA negative RA for smokers compared with never smokers, by age at smoking debut and cumulative dose of smoking
| ACPA positive RA | ||||||||
|---|---|---|---|---|---|---|---|---|
| Pack years of smoking Age at smoking debut |
0 | < 10 | 10–20 | > 20 | ||||
| 0 | 730/2655 | 1.0 (reference) | ||||||
| < 20 | 242/689 | 1.2 (1.0–1.4) | 302/530 | 2.1 (1.8–2.5) | 497/637 | 3.1 (2.7–3.4) | ||
| 20–25 | 115/310 | 1.3 (1.1–1.7) | 104/212 | 2.0 (1.6–2.6) | 133/183 | 3.0 (2.4–3.9) | ||
| > 25 | 129/382 | 1.3 (1.0–1.6) | 56/78 | 3.0 (2.0–4.3) | 23/50 | 1.9 (1.1–3.2) | ||
| ACPA negative RA | ||||||||
|---|---|---|---|---|---|---|---|---|
| Pack years of smoking Age at smoking debut |
0 | < 10 | 10–20 | > 20 | ||||
| 0 | 480/2655 | 1.0 (reference) | ||||||
| < 20 | 150/689 | 1.2 (1.0–1.5) | 119/530 | 1.2 (1.0–1.5) | 181/637 | 1.5 (1.2–1.8) | ||
| 20–25 | 72/310 | 1.3 (1.0–1.8) | 57/212 | 1.4 (1.1–2.0) | 49/183 | 1.4 (1.0–1.9) | ||
| > 25 | 69/382 | 1.1 (0.9–1.4) | 18/78 | 1.2 (0.7–2.0) | 14/50 | 1.5 (0.8–2.7) | ||
Adjusted for age, gender, residential area, study, ancestry, educational level, passive smoking, alcohol consumption, and body mass index at inclusion in the study