To analyze the influence of IL6R rs8192284 polymorphism on the disease activity of rheumatoid arthritis (RA).
Patients with RA (n = 281) were followed for a median of 4.2 years. A total of 1143 disease activity measurements using the 28-joint count Disease Activity Score (DAS28) were performed. A mixed-effect model was used to analyze the measurements.
A statistically significant interaction was observed between IL6R rs8192284 polymorphism and the presence of anticyclic citrullinated peptide (anti-CCP) antibodies (p = 0.008). An inverse relationship between the polymorphism and DAS28 was observed depending on anti-CCP status.
The anti-CCP status in patients with RA determines the association between the IL6R rs8192284 polymorphism and disease activity.