TY - JOUR
T1 - What influences early hypothyroidism after radioiodine treatment for Graves' hyperthyroidism?
AU - Vijayakumar, Vani
AU - Ali, Seham
AU - Nishino, Thomas
AU - Nusynowitz, Martin
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2006/11
Y1 - 2006/11
N2 - OBJECTIVE: The objective of this study was to evaluate the factors influencing the occurrence of early hypothyroidism after radioiodine treatment of Graves' hyperthyroidism. MATERIAL AND METHODS: Of 147 patients with Graves' disease (GD) treated with radioactive I-131 (RAI) in our thyroid clinic between July 2003 and December 2004, 84 were followed at 2 and 4 to 5 months after treatment. The age range was 12 to 75 years and the dosage range in these patients was 7.4 to 29.9 mCi. Twenty-four were males and 60 were females. Factors possibly contributing to post-RAI hypothyroidism are: dosage of I-131, age, gender, size of the gland, initial serum free T4, free T3, thyroid-stimulating hormone (TSH) levels, pretreatment with antithyroid drugs, radioactive iodine uptake, and duration of disease. RESULTS: All patients had low TSH, elevated FT4, and elevated radioactive iodine uptake (RAIU) at 4 and/or 24 hours. Of the 84 patients followed, 46% of the males and 62% of the females became hypothyroid at 4 to 5 months (57% of the total). Twenty-one patients remained hyperthyroid and 14 patients became euthyroid. Multivariate analysis of these 84 patients showed no statistically significant single contributing factor for the development of early hypothyroidism. CONCLUSION: The early onset of hypothyroidism after RAI in GD is very common (57%) and unpredictable. Thus, after RAI treatment, all patients must be closely monitored for the development of this disorder.
AB - OBJECTIVE: The objective of this study was to evaluate the factors influencing the occurrence of early hypothyroidism after radioiodine treatment of Graves' hyperthyroidism. MATERIAL AND METHODS: Of 147 patients with Graves' disease (GD) treated with radioactive I-131 (RAI) in our thyroid clinic between July 2003 and December 2004, 84 were followed at 2 and 4 to 5 months after treatment. The age range was 12 to 75 years and the dosage range in these patients was 7.4 to 29.9 mCi. Twenty-four were males and 60 were females. Factors possibly contributing to post-RAI hypothyroidism are: dosage of I-131, age, gender, size of the gland, initial serum free T4, free T3, thyroid-stimulating hormone (TSH) levels, pretreatment with antithyroid drugs, radioactive iodine uptake, and duration of disease. RESULTS: All patients had low TSH, elevated FT4, and elevated radioactive iodine uptake (RAIU) at 4 and/or 24 hours. Of the 84 patients followed, 46% of the males and 62% of the females became hypothyroid at 4 to 5 months (57% of the total). Twenty-one patients remained hyperthyroid and 14 patients became euthyroid. Multivariate analysis of these 84 patients showed no statistically significant single contributing factor for the development of early hypothyroidism. CONCLUSION: The early onset of hypothyroidism after RAI in GD is very common (57%) and unpredictable. Thus, after RAI treatment, all patients must be closely monitored for the development of this disorder.
KW - Hyperthyroidism
KW - Hypothyroidism
KW - I-131
KW - Radioactive iodine
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U2 - 10.1097/01.rlu.0000242213.26839.20
DO - 10.1097/01.rlu.0000242213.26839.20
M3 - Article
C2 - 17053385
AN - SCOPUS:33750374632
SN - 0363-9762
VL - 31
SP - 688
EP - 689
JO - Clinical nuclear medicine
JF - Clinical nuclear medicine
IS - 11
ER -