that is essential in making thyroid hormones, has been suggested in prior studies to improve symptoms of TED. It has long been known that smoking is associated with a higher incidence of TED. The present study suggests that a relative deficiency in selenium may also be a risk factor for TED and may provide a reason why selenium may be helpful in treating the disease.
THE FULL ARTICLE TITLE:
Khong JJ et al. Serum selenium status in Graves’ disease with and without orbitopathy: a case-control study. Clin Endocrinol (Oxf) 2014:80:905-910. Epub January 30, 2014.
SUMMARY OF THE STUDIES
A total of 198 patients with Graves’ disease were recruited from multiple clinics to participate in this study. Of these patients, 101 patients had moderate to severe TED and 97 patients had had Graves’ disease for more than 2 years with no evidence of TED. Patients with TED were older (54.1 vs. 47.4 years) and had a longer duration of Graves’ disease (8 years vs. 3 years). More patients with TED were current or former cigarette smokers and more were residents of surburban areas. Also, more patients in the TED group required radioactive iodine or thyroidectomy as treatment for their hyperthyroidism while more of those without TED were managed with antithyroid drugs alone. At the time of the study, the patients with TED had higher TSH levels and lower T3 levels than those without TED. The average selenium levels were significantly lower in the TED group (86.6 mcg/L vs. 93.7 mcg/L).
WHAT ARE THE IMPLICATIONS OF THIS STUDY?
This study suggests that is a small but significant difference in selenium levels in Graves’ disease patients with TED compared with patients who do not have TED. Therefore, relative selenium deficiency may be an independent risk factor for TED in patients with Graves’ disease. This suggests a reason why selenium supplementation may be helpful in treating patients with TED. Further studies are needed to determine whether selenium supplementation is beneficial in patients diagnosed with Graves’ disease to prevent development of TED.
—Frank Crantz, MD
ATA THYROID BROCHURE LINKS
Graves’ disease: http://www.thyroid.org/what-is-graves-disease
Radioactive iodine therapy: http://thyroid.org/radioactive-iodine