Disclosures: The authors report no relevant financial disclosures.
September 09, 2021
2 min read

Total thyroidectomy decreases thyrotropin receptor antibodies quicker in Graves’ disease

Disclosures: The authors report no relevant financial disclosures.
You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact customerservice@slackinc.com.

Changes in thyrotropin-binding inhibitory immunoglobulin levels for people with refractory Graves’ disease differed for those undergoing total thyroidectomy vs. radioactive iodine therapy, according to study data.

Adults with refractory Graves’ disease who underwent total thyroidectomy had a decrease in thyrotropin-binding inhibitory immunoglobulin (TBII) levels immediately after treatment, whereas levels increased for a short time for those undergoing radioactive iodine (RAI) therapy before later declining.

Participants who underwent a total thyroidectomy had a quicker decrease in thyrotropin receptor antibodies compared with people who had radioactive iodine therapy. Data were derived from Kim J, et al. Thyroid. 2021;doi:10.1089/thy.2020.0756.

“Patients in the total thyroidectomy group exhibited faster decline in TBII levels, consistent with the results of a previous study,” Sun Wook Kim, MD, PhD, assistant professor in the division of endocrinology and metabolism, department of medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine in Seoul, South Korea, and colleagues wrote in a study published in Thyroid. “We also confirmed that hyperthyroidism was immediately resolved after total thyroidectomy. The reduction in TBII levels in the total thyroidectomy group occurred faster, despite these individuals having more severe symptoms before treatment.”

Researchers conducted a retrospective review of 130 adults with Graves’ disease requiring treatment after antithyroid drug use and for whom TBII levels were available 3 months before treatment and 1 year after treatment. All participants underwent a total thyroidectomy or RAI therapy at Samsung Medical Center from 2011 to 2017.

Of the study cohort, 85 received RAI therapy and 45 underwent total thyroidectomy. Those who underwent total thyroidectomy had higher triiodothyronine (197.82 ng/dL vs. 158.98 ng/dL; P = .009) and baseline TBII levels (66.86 IU/L vs. 21.27 IU/L; P < .001) compared with the RAI therapy group. Those who underwent RAI therapy were older (mean age, 47.06 years vs. 40.24 years) and had a higher percentage of people with arrhythmia (23.5% vs. 4.4%) than the thyroidectomy group. There was no difference in the type or duration of antithyroid drug used between the two groups.

After treatment, all participants with thyroidectomy reached hypothyroidism, whereas 41.2% in the RAI group had recurrent hyperthyroidism and 18.8% did not experience hyperthyroid remission during the 2-year study period.

TBII levels decreased in the thyroidectomy group immediately after treatment, whereas those who underwent RAI therapy had an increase in TBII levels for a median of 138 days before values slowly decreased. TBII levels were significantly lower in the thyroidectomy group compared with RAI therapy 6 and 9 months after treatment.

The estimated median time for TBII levels to decrease below 4.5 IU was 316 days with total thyroidectomy and 659 days with RAI therapy. In the thyroidectomy group, older adults and those with high baseline TBII levels had slower reductions in levels, whereas the presence of a goiter was associated with a slower reduction of TBII levels in the RAI therapy group.

Despite the findings, researchers said it remains difficult to recommend total thyroidectomy as an initial treatment for Graves’ disease due to its cost and its invasiveness.

“The results of this study indicate that patients with severe Graves’ disease, who had high TBII levels, goiter and ophthalmopathy often underwent total thyroidectomy,” the researchers wrote. “In elderly patients or patients with arrhythmia, RAI would be preferred over surgery and these patients would likely easily accept RAI as the definitive treatment option.”