Early recurrence of hyperthyroidism in patients with Graves' disease treated by subtotal thyroidectomy.

Prerequisites for surgical treatment of Graves' disease are that it can be done safely and that it is associated with a low incidence of recurrent hyperthyroidism. Early recurrence is especially undesirable. We studied 728 patients with Graves' disease treated by subtotal thyroidectomy using multivariate analysis in order to determine the factors related to early recurrence. The following factors were analyzed: age, sex, duration of medical treatment, weight of resected thyroid tissue, thyroid remnant size, preoperative level of thyroid-stimulating hormone (TSH) binding inhibitory immunoglobulin (TBII), and antimicrosomal hemagglutination antibody (MCHA). "Early recurrence" was defined as TSH suppression observed within the first year after surgery and continuing for at least 6 months. A total of 106 patients (14.6%) had early recurrence. Statistical analyses were performed by the chi-square test for univariate analysis and a logistic model for multivariate analysis. Significant factors were thyroid remnant size, MCHA, and TBII. These results indicated that TBII and MCHA are related to early recurrence of hyperthyroidism, and smaller remnant size is recommended for patients with a high MCHA titer or a high TBII level (or both) in order to avoid early recurrence.