Characteristics of Japanese patients with Graves’ disease who fail first radioiodine therapy

Abstract

The factors predisposing to failure of radioiodine therapy (RIT) using ¹³¹I for Graves’ disease have been reported in various studies, but there are few reports from Japan. We investigated predictors of first RIT outcome. We retrospectively investigated outcomes of first RIT for 59 patients with Graves’ disease and divided into two groups with regard to the outcome of first RIT and factors associated with the failure of first RIT were determined. Binary logistic analysis showed thyroid weight as the only factor associated with outcome of first RIT. Receiver operating characteristic analysis demonstrated that the optimal cutoff value for thyroid weight to discriminate between patients who would or would not achieve success with first RIT was 33.4 g (81.6 % sensitivity, 80.0 % specificity; area under the curve, 0.837; 95 % confidence interval, 0.695–0.978; p < 0.001). Thyroid weight was the most important predictor of first RIT outcome.