Course of Graves' disease in interferon-treated patients with chronic hepatitis C virus infection and in uninfected patients

BACKGROUND: The development of thyroid antibodies and the alteration of thyroid function are the most common disorders associated with interferon alfa therapy in individuals with chronic hepatitis C (CHC).In this study, we compared the course of Graves disease (GD) between patients diagnosed with CHC and treated with interferon alfa and uninfected patients. METHODS: We retrospectively analyzed data from 39 GD patients (15 men and 24 women, group 1) affected by CHC and treated with interferon alfa and from 43 uninfected GD patients (19 men and 24 women, group 2) who were seen at our institution from 1999 to 2011. All GD patients were treated with methimazole (MMI). Daily dose of MMI, duration of MMI therapy, and remission rate were evaluated in both groups. RESULTS: The daily dose of MMI was found to be lower in group 1 as compared with group 2 (9.74 ± 5.94 mg/d vs 14.12 ± 8.64 mg/d in group 1 vs group 2, respectively, P < 0.01). In addition, the duration of MMI treatment was found to be lower in group 1 as compared with group 2 (13.98 ± 13.0 months vs 38.86 ± 27.13 months in group 1 vs group 2, respectively; P < 0.01). The remission rate from GD was higher in the patients of group 1 in comparison with the patients of group 2 (87.17 % vs 48.86% in group 1 vs group 2, respectively, P < 0.005). CONCLUSION: Altogether, our data demonstrate a more favorable course of GD in the patients with CHC treated with interferon alfa compared with GD occurring in the patients without CHC.