Selenium supplementation in inactive moderate to severe Graves' orbitopathy patients: a randomized controlled trial

PurposeThis study was designed to evaluate the effect of selenium supplementation in inactive moderate-severe Graves' orbitopathy (GO) patients.MethodsThis study was a single-center, placebo-controlled, double-masked, randomized trial. Inactive moderate-severe GO participants were randomized to receive six months of 200 micrograms/day of selenium supplementation or placebo. Thorough eye exams, clinical activity score (CAS), Graves' Ophthalmopathy quality of life questionnaire (GO-QOL), and serum selenium level were evaluated at baseline and 6 months after the interventions. The chi-squared or Fisher's exact test was used to compare categorical variables. The t-test and the paired t-test were used to compare continuous variables between two independent samples and two dependent samples, respectively.ResultsA total of 25 participants were enrolled, 13 in the selenium group and 12 in the placebo group. Both groups had adequate baseline serum selenium levels at 98.96 +/- 15.63 mcg/L and 102.55 +/- 17.71 mcg/L, respectively. After 6 months of intervention, the selenium group showed a greater improvement in palpebral aperture (mean difference: -1.4 +/- 1.7 mm, p = .04) compared to the placebo group (-0.3 +/- 2.7 mm). Notably, 5(41.67%) people in the placebo group developed larger palpebral apertures. Proptosis, ocular motility, and soft tissue signs did not change significantly. GO-QOL and CAS score improvement showed no statistically significant difference between both groups. Minor adverse effects were observed.ConclusionsSelenium supplementation has a positive effect on eyelid aperture even in inactive moderate-to-severe GO patients with a sufficient baseline selenium level.