Table 1.
Characteristics of 1033 women from the Nurses’ Health Study and Nurses’ Health Study II in a nested case-control study of rheumatoid arthritis, at the time of blood draw [1989-90 (NHS) or 1996-99 (NHSII)]
| Characteristics | Pre-RA Cases (n=255) |
Matched Controls (n=778) |
p value |
|---|---|---|---|
| Age at blood draw, years | 51.4 (8.0) | 51.4 (8.0) | matching factor |
| White | 250 (98.0%) | 758 (97.4%) | 0.45 |
| ≥2 ACPA subtypes present | 40 (15.7%) | 16 (2.1%) | <0.001 |
| BMI ≥25 | 126 (49.4%) | 313 (40.2%) | <0.01 |
| Smoking, pack-years | 12.3 (16.1) | 9.4 (15.7) | 0.01 |
| Cumulative average alcohol, g/day | 4.0 (5.3) | 5.5 (8.6) | <0.01 |
| ≥1 HLA-SE allele present* | 139 (56.0%) | 284 (42.5%) | <0.001 |
Presented as mean (SD) or n (%). P values are from univariable conditional logistic regression models. ACPA: anti-citrullinated protein antibody. BMI: body mass index.
*
HLA-SE: HLA-shared epitope (missing in 117 women). Presented as % of 248 pre-RA cases and 668 controls