A national study of postoperative thyroid hormone supplementation rates after thyroid lobectomy

The American Thyroid Association updated guidelines in 2015 to allow lobectomy for low-risk thyroid cancers. The objectives of this study were (1) to determine thyroid hormone supplementation rates after lobectomy and (2) to evaluate the effect of the American Thyroid Association guideline change on lobectomy and hormone supplementation rates among thyroid cancer patients.

The Merative MarketScan Databases was used to identify adult (≥age 18) patients who underwent thyroidectomy for benign nodules or thyroid cancer. The association between indication for surgery and postoperative thyroid hormone supplementation was examined using χ² analyses and multivariable logistic regression models. Among patients with thyroid cancer, lobectomy and hormone supplementation rates were compared in the periods before (2008-2015) and after the guideline change (2016-2019).

Of the 81,926 patients identified, 33,756 (41.2%) underwent thyroid lobectomy, 45,104 (55.1%) underwent total thyroidectomy, and 3,066 (3.7%) underwent completion thyroidectomy. Patients who underwent lobectomy for malignancy were significantly more likely to require hormone supplementation (59.3% vs 39.4% [P < .001], adjusted odds ratio 2.34 [95% confidence interval 2.20-2.48]) compared to those with benign disease. Compared to the 2008 to 2015 period, the proportion of patients who underwent lobectomy for thyroid cancer was higher in the 2016 to 2019 period (34.3% vs 30.3%, P < .001), with fewer patients requiring completion thyroidectomy (25.6% vs 29.8%, P < .001) and thyroid hormone supplementation (56.9% vs 60.1%, P = .04).

The postoperative thyroid hormone supplementation rate was significantly higher in patients who had thyroid cancers compared to benign diseases. After the American Thyroid Association guidelines changed, lobectomy rates increased significantly without a concomitant increase in the completion of thyroidectomy.