Selenium improves mild Graves’Orbitopathy: a randomized, double-blind, placebo-controlled study.

Background Free oxygen radicals and cytokines play a pathogenic role in Graves’ orbitopathy (GO). This study reports the results of a randomized, double-blind, placebo-controlled trial on the effect of selenium, an antioxidant agent, or pentoxifylline, an anti-inflammatory agent, on mild GO. Methods One hundred fifty-nine patients with untreated mild GO were randomized to receive either selenium (100 µg bid), or pentoxifylline (600 mg bid), or placebo (bid) tablets for 6 months and followed for 6 months after treatment withdrawal. Primary outcomes at 6 months were evaluated by an overall ophthalmic assessment by a blinded ophthalmologist and a GO -specific quality of life (GO-QoL) questionnaire completed by the masked patient. Secondary outcomes were evaluated by a Clinical Activity Score (CAS) and a diplopia score. Results At the 6- month evaluation treatment with selenium, but not with pentoxifylline, compared with placebo, was associated with improved GO-QoL (P<0.001) and eye involvement (P=0.01) and slowed the progression of GO (P=0.01). The CAS decreased in all groups, but the change was significantly greater in selenium-treated patients. Exploratory evaluation at 12 months confirmed the results at 6 months. Two patients assigned to placebo and one to pentoxifylline had deterioration in GO and required immunosuppresion therapy. Selenium had no evident adverse events, whereas pentoxifylline was associated with frequent gastrointestinal problems. Conclusions Selenium administration significantly improved the QoL and the eye involvement and slowed progression of the disease in patients with mild GO.