Incidence of hypothyroidism after 131I therapy for hyperthyroidism. Relation to pretherapy serum levels of T3, T4 and thyroid antibodies.
A correlation is reported between serum levels of triiodothyronine (S-T3) and thyroxine (S-T4) before treatment, as well as levels of thyroid antibodies before treatment, and the development of hypothyroidism following 131I therapy in 86 patients with hyperthyroidism. Patients with marked elevation of S-T3 or S-T4 had demonstrable antibodies to thyroid cytoplasmic antigen more often than those with normal or moderately elevated levels, and patients with markedly elevated levels of S-T3 also had a higher incidence of hypothyroidism after treatment. Patients with nodular thyroid glands and with markedly elevated levels of S-T3 required a larger number of 131I doses before no signs of hyperthyroidism persisted in comparison to those with moderately elevated levels.
D000328:Adult; D000368:Aged; D000906:Antibodies / Q000032:analysis; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000532:radiotherapy*; D007037:Hypothyroidism / Q000209:etiology*; D007457:Iodine Radioisotopes / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D013961:Thyroid Gland / Q000276:immunology; D013974:Thyroxine / Q000097:blood*; D014284:Triiodothyronine / Q000097:blood*
D000906:Antibodies; D007457:Iodine Radioisotopes; D014284:Triiodothyronine; D013974:Thyroxine