The results of sodium iodide 131I treatment of thyrotoxicosis in 1,168 patients (302 males, 866 females; 58.5% diffuse and 41.5% multinodular toxic goitre) are presented. At the end of the 1st year post-treatment, 54.4% were hypothyroid, and the incidence of hypothyroidism after the 2nd year increased by 3% per year. When the results were analysed according to the calculated radiation dose the thyroid, it was found that the cumulative incidence of hypothyroidism from 6 months to 2 years posttreatment rose almost proportionally to the dose in cases of doses of 1,500–15,000 rad, but increased very little for higher doses; however, the long-term incidence of hypothyroidism was almost independent of the thyroid dose. Multivariate analysis showed that the results of 131I therapy at 6 months depended also on sex (treatment being more effective in women), the consistency of the thyroid gland and the year of treatment, with the same radiation dose giving a higher incidence of hypothyroidism in patients treated recently, in comparison to those treated early in the period studied. Of the patients treated in the period 1978–1982 (mean dose, 300 μCi/g), 93.5% were cured with a single dose of 131I, and 78% were hypothyroid at 6 months post-treatment.
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Beling U, Einhorn J (1961) Incidence of hypothyroidism and recurrences following 131I treatment of hyperthyroidism. Acta Radiol (Ther) 56:275–288
Cunnien AJ, Hay ID, Gorman CA, Offord KP, Scanlon PW (1982) Radioiodine induced hypothyroidism in Graves' disease: factors associated with the increasing incidence. J Nucl Med 23:978–983
Freitas JE, Swanson DP, Gross MD, Sisson JC (1979) Iodine-131: Optimal therapy for hyperthyroidism in children and adolescents? J Nucl Med 20:847–850
Holm LE (1982) Changing annual incidence of hypothyroidism after 131I therapy for hyperthyroidism 1951–1975. J Nucl Med 23:108–112
Holm LE, Dahlquist I, Israelsson A, Lundell G (1980) Malignant thyroid tumors after 131I therapy. A retrospective cohort study. N Engl J Med 303:188–191
Holm LE, Lundell G, Israelsson A, Dahlquist I (1982) Incidence of hypothyroidism occuring long after iodine 131 therapy for hyperthyroidism. J Nucl Med 23:103–107
Malamos B, Koutras D, Marketos S, Rigopoulos G, Yataganas X, Binopoulos D, Sfontouris J, Pharmakiotis A, Vought RL, London WT (1967) Endemic goitre in Greece: an iodine balance study in the field. J Clin Endocrinol Metab 27:1372–1378
Peto R, Pike MC, Armitage P, Breslow NE, Cox DR, Howard SV, Mantel N, McPherson K, Peto J, Smith PG (1977) Design and analysis of randomized clinical trials requiring prolonged observation of each patient. Br J Cancer 35:1–39
Saenger EL, Thoma GE, Thompkins EA (1968) Incidence of leukemia following treatment of hyperthyroidism. JAMA 205:855–862
Safa AM, Skillern PG (1975) Treatment of hyperthyroidism with a large initial dose of sodium iodide 131I. Arch Intern Med 135:673–675
Sridama V, McCormick M, Kaplan EL, Fauchet R, DeGroot LJ (1984) Long-term follow-up study of compensated low-dose 131I therapy for Graves' disease. New Engl J Med 311:426–432
Wise SC, Ahmad A, Burnet RB, Harding PE (1975) Intentional radioiodine ablation in Graves' disease. Lancet 2:1231–1233
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Alevizaki, C.C., Alevizaki-Harhalaki, M.C. & Ikkos, D.G. Radioiodine-131 treatment of thyrotoxicosis: dose required for and some factors affecting the early induction of hypothyroidism. Eur J Nucl Med 10, 450–454 (1985). https://doi.org/10.1007/BF00256589
- iodine 131 therapy