ACPA-positive RA | ACPA-negative RA | |||||
Duration | ca/co* | OR (95% CI)† | p Value | ca/co* | OR (95% CI)† | p Value |
0 | 828/1537 | 1.0 (reference) | 514/1537 | 1.0 (reference) | ||
<5 years | 149/275 | 0.8 (0.6 to 1.0) | 0.06 | 81/275 | 0.9 (0.7 to 1.2) | 0.5 |
5–10 years | 45/89 | 0.7 (5.1 to 1.1) | 0.1 | 24/89 | 0.8 (0.5 to 1.3) | 0.4 |
>10 years | 65/152 | 0.6 (0.4 to 0.9) | 0.005 | 35/152 | 0.7 (0.4 to 1.0) | 0.06 |
p for trend | 0.002 | 0.04 | ||||
Intensity | ca/co* | OR (95% CI)† | p | ca/co* | OR (95% CI)† | p |
0 | 828/1537 | 1.0 (reference) | 514/1537 | 1.0 (reference) | ||
<10 nights/months | 184/362 | 0.8 (0.6 to 1.0) | 0.02 | 97/362 | 0.8 (0.6 to 1.1) | 0.1 |
>10 nights/months | 75/154 | 0.7 (0.5 to 1.0) | 0.03 | 43/154 | 0.8 (0.6 to 1.2) | 0.4 |
p for trend | 0.007 | 0.2 |
*Number of exposed cases and controls.
†Adjusted for age, gender, residential area, ancestry, smoking, educational level and shift work.
ACPA, anticitrullinated peptide antibodies.