Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Kyungpook National University, Daegu, Korea.
Ann Surg Oncol. 2019 Dec;26(13):4405-4413. doi: 10.1245/s10434-019-07786-x. Epub 2019 Sep 5.
The goal of the present study was to determine the actual incidence, predictive risk factors, and clinical characteristics of levothyroxine supplementation (LT4S) used for the management of hypothyroidism after hemithyroidectomy.
From 2008 to 2015, we included 535 patients who underwent hemithyroidectomy. LT4S was initiated based on three major criteria: the development of overt hypothyroidism, subclinical hypothyroidism with thyroid-stimulating hormone (TSH) levels > 10 mIU/L, or subclinical hypothyroidism with TSH levels of 4.5-10 mIU/L with associated signs/symptoms.
During the 69-month follow-up period, 321 patients (60%) developed overall hypothyroidism following hemithyroidectomy, and 141 ultimately required LT4S, with an overall LT4S incidence of 26.4%. The most common cause of LT4S initiation was subclinical hypothyroidism with TSH levels > 10 mIU/L. In 141 patients with LT4S, the mean maintenance dose of levothyroxine was 1.34 μg/kg, and only 6 patients (4.3%) discontinued LT4S during the follow-up. The 1-, 3-, 5-, and 7-year LT4S-free survival rates of 535 patients were 88.6%, 80.2%, 73.8%, and 69.1%, respectively. Preoperative TSH levels > 2.12 mIU/L and coexistence of Hashimoto's thyroiditis were significantly associated with LT4S following hemithyroidectomy. The risk of LT4S increased by 1.401 times, as preoperative TSH levels increased by 1 mIU/L.
A quarter of patients required LT4S after hemithyroidectomy for the management of hypothyroidism, with a mean maintenance levothyroxine dose of 1.34 μg/kg. The preoperative TSH level and coexistence of Hashimoto's thyroiditis were significant predictive factors of LT4S following hemithyroidectomy.
本研究的目的是确定甲状腺次全切除术后用于治疗甲状腺功能减退症的左甲状腺素补充（LT4S）的实际发生率、预测风险因素和临床特征。
我们纳入了 2008 年至 2015 年间接受甲状腺次全切除术的 535 例患者。LT4S 的启动基于三个主要标准：出现显性甲状腺功能减退症、促甲状腺激素（TSH）水平>10 mIU/L 的亚临床甲状腺功能减退症或 TSH 水平为 4.5-10 mIU/L 且伴有相关体征/症状的亚临床甲状腺功能减退症。
在 69 个月的随访期间，321 例（60%）患者在甲状腺次全切除术后出现总体甲状腺功能减退症，其中 141 例最终需要 LT4S，LT4S 的总发生率为 26.4%。LT4S 启动的最常见原因是 TSH 水平>10 mIU/L 的亚临床甲状腺功能减退症。在 141 例接受 LT4S 的患者中，左甲状腺素的平均维持剂量为 1.34μg/kg，只有 6 例（4.3%）患者在随访期间停止 LT4S。535 例患者的 1、3、5 和 7 年 LT4S 无复发生存率分别为 88.6%、80.2%、73.8%和 69.1%。术前 TSH 水平>2.12 mIU/L 和桥本甲状腺炎共存与甲状腺次全切除术后 LT4S 显著相关。术前 TSH 水平每增加 1 mIU/L，LT4S 的风险增加 1.401 倍。
四分之一的患者在甲状腺次全切除术后需要 LT4S 来治疗甲状腺功能减退症，左甲状腺素的平均维持剂量为 1.34μg/kg。术前 TSH 水平和桥本甲状腺炎共存是甲状腺次全切除术后 LT4S 的显著预测因素。
