Incident RA in relation to farm tasks reported by applicators at enrolment
| Tasks (at least once per year) | RA cases n=196 | |
| N (%) | HR (95% CI)* | |
| Veterinary services | 97 (49) | 0.83 (0.62 to 1.14) |
| Butcher animals | 29 (15) | 0.99 (0.66 to 1.50) |
| Work in swine areas | 52 (26) | 0.99 (0.70 to 1.41) |
| Work in poultry areas | 5 (3) | 0.64 (0.26 to 1.56) |
| Load/unload silage | 43 (22) | 1.15 (0.80 to 1.66) |
| Grind animal feed | 92 (47) | 1.12 (0.81 to 1.54) |
| Handle stored grain | 133 (68) | 0.96 (0.65 to 1.40) |
| Handle stored hay | 108 (55) | 0.93 (0.69 to 1.25) |
| Repair engines | 92 (47) | 1.10 (0.82 to 1.46) |
| Replace asbestos brakes | 40 (20) | 1.23 (0.86 to 1.75) |
| Weld | 135 (69) | 0.95 (0.68 to 1.23) |
| Paint | 136 (69) | 1.04 (0.80 to 1.43) |
| Repair pesticide equipment | 131 (67) | 0.95 (0.69 to 1.31) |
*Results shown for enrolled applicators with complete data on pesticide covariates and diagnosis age (196 cases and 24 357 non-cases).
†HRs and 95% CIs estimated by cox proportional hazards model adjusting for state, participant type (applicator/spouse), smoking pack-years, education and pesticides. HRs allowed to vary by the median age (ie, 62 years) when proportional hazards assumption was not met (p≤0.10).
RA, rheumatoid arthritis.