Relative risks (odds ratio with 95% confidence intervals, CI) of RF positive RA in middle and highest tertiles of serum IgG and IgA concentrations compared with the lowest tertiles, as adjusted for serum orosomucoid, body mass index, smoking, alcohol intake, and level of education
| Mid tertile | Highest tertile | p for trend | |||||||
| Odds ratio | 95% CI | Odds ratio | 95% CI | ||||||
| IgG | 1.55 | (0.81–2.97) | 2.22 | (1.16–4.26) | 0.01 | ||||
| IgA | 2.23 | (1.14–4.36) | 1.78 | (0.89–3.57) | 0.81 | ||||