Age group (years) | Subjects exposed to silica overall v unexposed | Subjects who had worked with rock drilling or stone crushing v unexposed | |||||
---|---|---|---|---|---|---|---|
No of exposed cases | OR* | 95% CI | No of exposed cases | OR* | 95% CI | ||
*Adjusted for the potential confounding from age, residential area, and cigarette smoking. | |||||||
CI, confidence interval; OR, odds ratio; RA, rheumatoid arthritis; RF, rheumatoid factor. | |||||||
RF+ RA | 18 to 49 | 7 | 1.4 | 0.4 to 4.5 | 2 | 4.1 | 0.3 to 53.5 |
50 to 70 | 20 | 2.2 | 0.8 to 5.8 | 13 | 3.2 | 0.8 to 12.0 | |
18 to 70 | 27 | 1.9 | 0.9 to 4.0 | 15 | 3.5 | 1.1 to 11.2 | |
RF− RA | 18 to 49 | 3 | 1.8 | 0.1 to 25.8 | 1 | 0.7 | 0.0 to 18.1 |
50 to 70 | 11 | 3.3 | 0.9 to 12.3 | 3 | 3.0 | 0.3 to 28.8 | |
18 to 70 | 14 | 2.1 | 0.8 to 5.1 | 4 | 1.7 | 0.3 to 9.3 | |
Total RA | 18 to 49 | 10 | 1.6 | 0.6 to 4.4 | 3 | 2.6 | 0.4 to 18.1 |
50 to 70 | 31 | 2.7 | 1.2 to 5.8 | 16 | 3.3 | 1.1 to 10.1 | |
18 to 70 | 41 | 2.2 | 1.2 to 3.9 | 19 | 3.0 | 1.2 to 7.6 |