Risk of developing ACPA-positive RA among participants exposed to prolonged repetitive physical workload and SE genes in the EIRA
| 5 years before baseline | |||||
|---|---|---|---|---|---|
| Types of physical workloads | HLA-DRB1 SE negative | HLA-DRB1 SE positive | |||
| Cases/controls | OR* (95% CI) | Cases/controls | OR* (95% CI) | ||
| Repetitive bending/turning | Unexposed | 89/356 | 1.0 (ref) | 391/357 | 4.4 (3.3 to 5.7) |
| Exposed | 136/469 | 1.2 (0.9 to 1.6) | 811/485 | 6.9 (5.3 to 9.0) | |
| AP | 0.3 (0.2 to 0.5) | ||||
| Repetitive hand/finger movements | Unexposed | 79/282 | 1.0 (ref) | 348/298 | 4.2 (3.1 to 5.6) |
| Exposed | 146/543 | 1.0 (0.7 to 1.3) | 853/542 | 5.7 (4.3 to 7.5) | |
| AP | 0.3 (0.1 to 0.4) | ||||
| Lift or carry more than 10 kg | Unexposed | 116/437 | 1.0 (ref) | 539/451 | 4.6 (3.6 to 5.8) |
| Exposed | 109/388 | 1.1 (0.8 to 1.4) | 662/390 | 6.4 (5.0 to 8.2) | |
| AP | 0.3 (0.1 to 0.4) | ||||
| Precision work | Unexposed | 202/731 | 1.0 (ref) | 1068/747 | 5.3 (4.4 to 6.3) |
| Exposed | 22/92 | 0.9 (0.5 to 1.4) | 131/92 | 5.1 (3.7 to 7.0) | |
| AP | 0.0 (−0.3 to 0.3) | ||||
| Hands below knee level | Unexposed | 179/690 | 1.0 (ref) | 925/711 | 5.1 (4.2 to 6.2) |
| Exposed | 46/134 | 1.4 (0.9 to 2.0) | 276/130 | 8.5 (6.4 to 11.1) | |
| AP | 0.4 (0.2 to 0.5) | ||||
| Hands above shoulder level | Unexposed | 170/669 | 1.0 (ref) | 839/675 | 5.0 (4.1 to 6.1) |
| Exposed | 55/154 | 1.5 (1.0 to 2.1) | 359/167 | 8.9 (6.9 to 11.5) | |
| AP | 0.4 (0.3 to 0.5) | ||||
| Vibration | Unexposed | 194/710 | 1.0 (ref) | 980/714 | 5.1 (4.2 to 6.1) |
| Exposed | 31/114 | 1.0 (0.6 to 1.6) | 221/125 | 6.8 (5.1 to 9.1) | |
| AP | 0.3 (0.0 to 0.5) | ||||
Baseline is the year when the participants were diagnosed with RA.
Values are OR and 95% CI as compared with unexposed and no SE reference group.
*OR adjusted for age (10 strata), sex and residential area.
ACPA, anticitrullinated protein antibody; AP, attributable proportion due to interaction; EIRA, Epidemiological Investigation of Rheumatoid Arthritis; RA, rheumatoid arthritis; ref, reference; SE, shared epitope.