Characteristics of female rheumatoid arthritis (RA) cases and female controls in the Malaysian Epidemiological Investigation of Rheumatoid Arthritis (MyEIRA) study
| Female RA cases (n=910) | Female controls (n=910) | |
|---|---|---|
| Mean age (SD) | 47.5 (11.4) | 47.4 (11.3) |
| Ethnicity | ||
| Malay | 381 (41.9) | 591 (65.0) |
| Chinese | 182 (20.0) | 105 (11.5) |
| Indian | 307 (33.7) | 159 (17.5) |
| Others | 40 (4.4) | 55 (6.0) |
| Educational level | ||
| No formal education | 41 (4.5) | 64 (7.0) |
| Primary education | 202 (22.2) | 222 (24.4) |
| Secondary education | 479 (52.6) | 444 (48.8) |
| College/university | 184 (20.2) | 177 (19.5) |
| Missing information | 4 (0.4) | 3 (0.3) |
| ACPA | ||
| Positive | 575 (63.2) | 18 (2.0) |
| Negative | 325 (36.8) | 892 (98.0) |
| HLA-DRB1 SE alleles | ||
| Positive | 360 (39.6) | 147 (16.0) |
| Negative | 549 (60.3) | 763 (84.0) |
| Missing information | 1 (0.1) | 0 |
| Smoking habits | ||
| Never smoker | 870 (95.6) | 884 (97.2) |
| Ever smoker | 9 (1.0) | 4 (0.4) |
| Missing information | 31 (3.4) | 22 (2.4) |
| Textile dust exposure | ||
| Occupational exposed | 41 (4.5) | 15 (1.7) |
| Unexposed | 622 (68.4) | 647 (71.1) |
| Missing information | 53 (5.8) | 35 (3.8) |
ACPA, anti-citrullinated peptides antibody; HLA-DRB1 SE, human leucocyte antigen DR β-1 chain shared epitope.