Early agalactosylation of IgG is associated with a more progressive disease course in patients with rheumatoid arthritis: results of a follow-up study.

The clinical significance of the percentage agalactosyl IgG oligosaccharides [%G(O)] was investigated in serum of a well-characterized cohort of 127 female RA patients who were followed for a mean duration of 6 yr. The %G(O) was determined in the first available serum sample which was obtained at a mean of 3.4 yr after symptom onset. It could be shown that patients with a %G(O) more than 2 S.D. above the mean level of controls (n = 34), had significantly more erosions, disease activity, and were treated with more second-line drugs, than patients without an increased %G(O) (n = 93), both at the time the serum sample was obtained, and during follow-up. These findings suggest that G(O) may serve as an indicator for the disease course in patients with RA.