Outcomes of Patients With Graves Disease 25 Years After Initiating Antithyroid Drug Therapy

Context Graves disease (GD) is a leading cause of hyperthyroidism. Detailed investigations and predictors of long-term outcomes are missing.Objective This work aimed to investigate the outcomes in GD 25 years after initiating antithyroid drug treatment, including disease course, clinical and biochemical predictors of relapse, and quality of life.Methods A retrospective follow-up was conducted of GD patients that participated in a randomized trial from 1997 to 2001. Demographic and clinical data were obtained from medical records and questionnaires. Biobank samples were analyzed for inflammatory biomarkers and compared with age- and sex-matched healthy individuals.Results We included 83% (182/218) of the patients from the original study. At the end of follow-up, normal thyroid function was achieved in 34%. The remaining had either active disease (1%), spontaneous hypothyroidism (13%), or had undergone ablative treatment with radioiodine (40%) or thyroidectomy (13%). Age younger than or equal to 40 years, thyroid eye disease (TED), smoking, and elevated levels of interleukin 6 and tumor necrosis factor receptor superfamily member 9 (TNFRS9) increased the risk of relapsing disease (odds ratio 3.22; 2.26; 2.21; 1.99; 2.36). At the end of treatment, CD40 was lower in patients who maintained normal thyroid function (P = .04). At the end of follow-up, 47% had one or more autoimmune diseases, including vitamin B12 deficiency (26%) and rheumatoid arthritis (5%). GD patients who developed hypothyroidism had reduced quality of life.Conclusion Careful lifelong monitoring is indicated to detect recurrence, hypothyroidism, and other autoimmune diseases. Long-term ATD treatment emerges as a beneficial first-line treatment option, especially in patients with young age at onset or presence of TED.