Table 1

Odds ratio (OR) with 95% CI of developing ACPA-positive RA, ACPA-negative RA and RA overall, respectively, among men exposed to stone dust, rock drilling, stone crushing and silica overall, respectively, compared with men unexposed to silica

ExposureCategory of RANumber of exposed cases/exposed controlsOR*95% CI
Stone dustACPA-positive RA44/581.601.04 to 2.44
ACPA-negative RA17/581.020.57 to 1.82
RA overall67/581.380.95 to 2.02
Rock-drillingACPA-positive RA18/172.341.17 to 4.68
ACPA-negative RA5/170.960.34 to 2.67
RA overall26/171.830.97 to 3.43
Stone crushingACPA-positive RA11/132.030.88 to 4.67
ACPA-negative RA5/131.340.45 to 3.97
RA overall17/131.620.77 to 3.43
Silica overallACPA-positive RA54/691.671.13 to 2.48
ACPA-negative RA20/690.980.57 to 1.66
RA overall80/691.390.98 to 1.96
  • * OR adjusted for the potential confounding from age and residential area.

  • ACPA, antibodies against citrullinated peptide antigens; RA, rheumatoid arthritis.