6662 Effect of Selenium Supplementation on Mild Graves’ Ophthalmopathy at a Tertiary Hospital - A Six-Month Open-Labelled, Assessor-Masked, Randomized-Controlled Trial

Abstract Disclosure: J.M. Flores: None. N.G. Sioson: None. J.D. Uy-Ho: None. A.L. Suller-Pansacola: None. Graves’ orbitopathy is associated with increased oxidative stress. Selenium, with its antioxidant and immunoregulatory actions, has been proposed as an adjuvant therapy. Objective: This study was undertaken to determine whether selenium supplementation for six months can decrease signs and prevent worsening of mild Graves ophthalmopathy among Filipinos. Methods: We conducted an open-labelled, assessor-masked, Randomized-Controlled Trial on patients with mild Graves’ ophthalmopathy wherein one arm was assigned to standard of care (eye drops) only for a period of six months while another arm was assigned to 200 ug/day oral Selenium supplementation alongside standard of care. Population: Adult patients with Graves’ hyperthyroidism, with at least one sign of mild ophthalmopathy with GO disease duration of less than 18 months Results: Independent Sample T-test, Mann-Whitney U test and Fisher’s Exact/Chi-square test were used to determine the difference of mean, rank and frequency, between patients given Selenium versus patients given standard of care. Paired Sample T-test, Wilcoxon Sign rank test and McNemar test were used to determine the difference of mean, rank and frequency on patients from initial to 3rd month or 6th month observation. Null hypotheses were rejected at 0.05α-level of significance. There was a significant difference in Clinical Activity Score (CAS) between patients given selenium supplementation and those assigned to standard of care. On initial examination for the Selenium group, 14 eyes (33.33%) had a CAS score of 0, which increased to 27 eyes (64.29%) on the third month and ended to a 26 eyes (61.9%) at the sixth month of treatment. For the non-selenium group, 11 eyes had a CAS score of zero initially, increased to 16 eyes (and 38.1%) then finally arrived to a total count of 14 eyes (33.33%). Improvement in CAS may be attributed specifically to improvement in caruncle/plical swelling showing a significant difference (p-value 0.040). Comparing the two groups, a statistical significance in CAS is noted between the treatment versus the control group with a p-value of 0.017 on the 6th month. Conclusion: Selenium supplementation provided significant benefit in terms of decreasing signs and preventing worsening of mild GO through improved CAS score. Further studies exploring the baseline and end of treatment selenium concentrations in the Philippines may be warranted. Presentation: 6/3/2024