Association between Clinical Activity Score and Serum Interleukin-6, Interleukin-8 and Interleukin-10 during Systemic Glucocorticoid Treatment for Active Moderate-to-Severe Graves’ Orbitopathy

Abstract

ABSTRACT Purpose: Some interleukins (ILs) play an important role in Graves’ orbitopathy (GO) pathogenesis. We aimed to compare serum IL-6, IL-8 and IL-10 in GO patients, patients with Graves’ disease (GD) without GO and healthy controls (HC); to follow IL changes during glucocorticoid (GC) treatment for GO; to examine associations between ILs and Clinical Activity Score (CAS). Materials and Methods: Thirty-one patients with active moderate-to-severe GO (GO(+) group), 30 patients with GD without GO (GO(-) group) and 30 HC were enrolled. At baseline, ILs were measured in all groups, CAS was evaluated in GO(+) patients, who were then treated with systemic GCs for 12 weeks. ILs and CAS were reassessed after the first week of treatment (W2) and at the end of the therapy (W12). Results: At baseline, IL-6 was significantly higher in GO(+) and GO(-) patients, IL-8 – higher in GO(-) patients and IL-10 – lower in GO(+) patients compared to HC. Baseline ILs did not correlate with CAS. At W2, all ILs and CAS decreased significantly. At W12, CAS decreased further, IL-6 remained low, IL-8 and IL-10 returned to baseline. CAS reduction correlated positively with IL-6 reduction at W12 (ρ = 0.38, p = .04). GO(+) patients with overall CAS reduction≥2 had higher baseline IL-6 (3.4 vs 2.6 pg/ml, p = .15), smaller IL-10 reduction at W2 (10.5 vs 18.2%, p = .09), lower IL-6 (1.4 vs 2.4 pg/ml, p < .01) and higher IL-6 reduction at W12 (48.6 vs 21.4%, p = .01) compared to patients with CAS reduction<2. Logistic regression analysis confirmed that overall CAS reduction≥2 was associated with higher baseline IL-6, lower IL-6 at W12 and smaller IL-10 reduction at W2 (R2 = 0.66). Conclusions: Higher baseline IL-6, lower IL-6 at W12 and smaller IL-10 reduction at W2 were associated with higher probability of significant overall CAS reduction. IL-6 might be a potential additional marker for assessing disease activity.