The same autoimmune process is thought to cause thyroid associated ophthalmopathy (TAO) and Graves' disease. The aim of this study is to determine hether thyroid autoantibody is related to the development of thyroid associated ophthalmopathy.

A retrospective chart analysis was performed on patients with a newly diagnosed Graves' disease, who presented to our ophthalmology clinic between January 2006 and December 2009. Thyroid autoantibody titers were obtained at the time of diagnosis and were used to determine the presence or absence of TAO. In addition, any correlations between thyroid autoantibodies were analyzed in patients with TAO.

Thyroid autoantibody levels correlated with the development of TAO. Fifty-eight (69%) out of 84 patients with positive thyroid-stimulating hormone receptor antibody (TRAB) levels at the time of diagnosis had TAO. Only 50 (51%) of the 99 patients with negative TRAB levels had TAO. This difference between the two groups was statistically significant (odds ratio, OR=2.2, p =0.013). A statistically significant correlation with the development of TAO was also found in thyroid peroxidase antibody (TPOAb) and anti-thyroglobulin antibody (TgAb), respectively (OR=0.5, p=0.317; OR=0.3, p=<0.001). In patients with TAO, the correlation between TPOAb and TgAb levels was very high (r=0.64, p =<0.001).

A significant association was determined to exist between the development of TAO and thyroid autoantibody level. This result demonstrates the clinical utility of thyroid autoantibody for the diagnosis of TAO in patients with newly diagnosed Graves' disease.