Identification of a subgroup of Graves' disease patients at higher risk for severe ophthalmopathy after radioiodine.

We have analyzed retrospectively the records of 89 patients with Graves' disease who were treated with radioiodine between 1980-88 and whose ophthalmopathy was recorded in a uniform manner initially and after 5 and 12 months. Moreover information on progression of eye disease was obtained by telephone for all patients after an average of 72 months. Pretreatment endocrine ophthalmopathy (class greater than or equal to 1 of classification of American Thyroid Association) was present in 34% of the patients. Eight patients developed proptosis over 20 mm, 7 patients severe ophthalmopathy (classes 4 to 6), 5 patients required special treatment for eye disease. Among the 30 patients with initial ophthalmopathy, severe ophthalmopathy (5 of 30; p less than 0.05) and proptosis greater than 20 mm 16 of 30; p less than 0.05) developed in significantly more cases than in patients with no pretreatment ophthalmopathy. The data suggest that hyperthyroid patients with pretreatment ophthalmopathy are at risk for developing severe ophthalmopathy after 131I treatment.