In these analyses (the results of which are presented in detail in Supplemental Table 3) baseline or incident dual RF-IgA and RF-IgM positivity was associated with a significantly higher risk for incident IA/RA (Hazard Ratio 3.09, 95% Confidence Interval 1.15 to 8.29, p=0.025). This evidence concerns the gene CD79A and rheumatoid arthritis.