Clinical Thyroidology for the Public summarizes selected research studies discussed in the previous month’s issue of Clinical Thyroidology, an official publication of the American Thyroid Association. Editor-in-chief, Alan Farwell, MD, FACE

Volume 16 Issue 3

March is Medullary Thyroid Cancer Awareness Month

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Clinical Thyroidology for the Public Volume 16 Issue 3 (PDF file, 2.58 MB)



Long-term, low-dose methimazole therapy is effective in protecting against relapses in Graves’ disease

Anti-thyroid drugs are used to control Graves’ disease with the hope that the disease will go into remission. However, after stopping this medication, about 40-50% of the patients experience a relapse of their hyperthyroidism. This study was conducted to understand whether long-term therapy with low-dose MMI could protect Graves’ disease patients from relapses of hyperthyroidism.
Lertwattanarak R et al 2022 Benefits of Long-term continuation of low-dose methimazole therapy in the prevention of recurrent hyperthyroidism in Graves’ hyperthyroid patients: A randomized prospective controlled study. Int J Endocrinol 2022:1705740. PMID: 36267362.

Predictors of radioactive iodine treatment failure in Graves’ Disease

Radioactive iodine therapy is a common treatment for Graves’ disease. Sometimes radioactive iodine therapy fails to treat the hyperthyroidism and patients can require either repeat radioactive iodine therapy treatments or alternative treatments including antithyroid medications or surgery to control the overactive thyroid. This study sought to examine the factors that predict radioactive iodine therapy failure in patients with Graves’ disease.
Shalaby M et al Predictive factors of radioiodine therapy failure in Graves’ Disease: A meta-analysis. Am. J. Surgery. 223 287-296. 2021. PMID: 33865565.

Positive thyroid antibody levels in mothers during pregnancy are associated with higher risks of behavioral problems in pre-school children.

Elevated thyroid antibodies in the mother during pregnancy have also been associated with higher risks of attention-deficit/ hyperactivity disorder (ADHD) or autism spectrum disorder in the babies in some studies. However, not all studies show similar results and other studies report no such associations. Given the lack of clear findings, this study evaluated potential associations between elevated thyroid antibodies in the mother during pregnancy and emotional and behavioral development in preschool-aged children.
Teng Y et al 2022 Sex-specific effect of thyroid peroxidase antibody and thyroglobulin antibody exposure during pregnancy on preschoolers’ emotional and behavioral development: A birth cohort study. Thyroid 32:1229–1242. PMID: 35920111.

Rate of thyroid hormone replacement after lobectomy for benign disease is higher than previously estimated

Currently, hypothyroidism requiring thyroid hormone therapy following lobectomy may occur in 8 to 50% of cases. There is an increased likelihood of hypothyroidism after lobectomy in patients with elevated TSH levels before surgery, positive thyroid peroxidase antibodies, thyroid cancer as the reason for the surgery, and small thyroid tissue left behind. This study was performed to determine the frequency of hypothyroidism and timing of beginning thyroid hormone therapy after lobectomy over a 15-year follow-up period.
Barranco H et al 2023 Thyroid hormone replacement following lobectomy: Long-term institutional analysis 15 years after surgery. Surgery 173:189–192.

Do people who previously underwent weight loss surgery have lower body calcium levels after thyroid surgery?

Damage to the parathyroid glands that control calcium levels is a complication of thyroid surgery and can lead to hypocalcemia. Bariatric surgery to promote weight loss by either decreasing the size of the stomach or re-routing the path of food through the intestines is an effective treatment for severe obesity but also can decrease the absorption of calcium and Vitamin D. This study aimed to determine if people who underwent bariatric surgery and then subsequently undergo thyroid surgery are more likely to have low calcium levels than thyroid surgery patients who have not had bariatric surgery.
Lorenz FJ et al 2022 Hypocalcemia after thyroidectomy in patients with prior bariatric surgery: A propensity score matched analysis from a national administrative database. Thyroid 32:1382–1391.

Active surveillance of low-risk thyroid cancer is not easy

The option following certain small low risk papillary cancers with ultrasound and deferring surgery, known as active surveillance, has been described as an alternative to surgical treatment by some groups in Japan, and, more recently, in the United States. However, it is not very clear what are the rates of use of active surveillance in the United States, outside of selected centers. This study was done in order to understand physicians’ attitudes toward use of active surveillance, how often it is being used, and what are the barriers to its use in a diverse group of physicians who treat thyroid cancer patients in the general population.
Hughes DT et 2022 Barriers to the use of active surveillance for thyroid cancer: Results of a physician survey. Ann Surg 276(1):e40–e47. PMID: 33074908.