Serum selenium status in Egyptians patients who had Graves' disease with and without ophthalmopathy

Selenium is efficient in reducing the progression of active Graves' orbitopathy and improving life quality. The impact of mending relative deficiency of selenium on improving Graves' orbitopathy is not known, due to the lack of previous measurement of baseline levels of selenium. The study object was to determine whether serum selenium levels are lower in patients with Graves' ophthalmopathy (GO) disease in comparison with those without ophthalmopathy. This prospective case control study was conducted between 2019 and 2021 at the endocrine and ophthalmology clinics, Ain Shams University, Cairo. The study included a total of 75 subjects, 50 patients with Graves' disease (GD) and 25 subjects as a control group. Of the GD patients, 25 had Graves' orbitopathy. Serum selenium concentrations were measured in each group. The mean level of serum selenium was significantly lower in patients with Graves' orbitopathy (16.6 ± 7.5 ng/ml) than in patients with Graves' disease (42.9 ± 8.2 ng/ml) (p < 0.001). Mean selenium levels were reduced with increasing severity of GO, as selenium level was 30-55 ng/ml in GD, 21-28 ng/ml in mild GO, 18-22 ng/ml in moderate GO and 5-16 ng/ml in severe GO (p < 0.001). In conclusion, serum selenium levels were lower in GO patients compared with GD patients in an Egyptian population. Low selenium levels may be a risk factor for ophthalmopathy in Graves' disease patients.