The efficacy and safety of selenium supplementation versus placebo in the treatment of Graves' orbitopathy: A systematic review and meta-analysis of randomised controlled trials.

Background: Selenium is a trace element crucial for thyroid function, and has potential therapeutic benefits in Graves' orbitopathy (GO). Therefore, we aim to evaluate its efficacy and safety in GO patients to provide valuable insights into its role as a therapeutic option for this condition.

Design: Systematic review and meta-analysis.

Patients: GO Patients treated with selenium compared to placebo.

Measurements: Clinical activity score (CAS), Graves' orbitopathy quality of life (GO-QOL), eye symptoms and signs, and adverse events.

Results: Out of 1684 records screened, four randomised controlled trials were included. Selenium was superior at 6 months in lowering the CAS (MD = -1.27, 95% confidence interval [CI] [-1.68, -0.85], p < .0001]), improving total GO-QOL (RR = 2.54, 95% CI [1.69-3.81], p < .00001), and improving the visual and the psychological functioning scores (MD = 10.84, 95% CI [4.94-16.73], p = .003), (MD = 12.76, 95% CI [8.51-17.00], p < .00001) respectively. Similarly, it significantly improved these outcomes at 12 months. It also showed a significant decrease in the palpebral aperture at 6 months (MD = -1.49, 95% CI [-2.90, -0.08], p = .04). However, no significant differences were observed in proptosis, soft tissue involvement, ocular motility, and adverse effects.

Conclusions: Selenium is effective in reducing CAS and improving the palpebral aperture and GO-QOL in patients with GO. Additionally, it is safe and has promising therapeutic implications. However, further research is needed to validate its long-term efficacy and safety.