Department of Diabetes, Endocrinology, Nutritional Medicine and Metabolism, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
Division of Clinical Pharmacy and Epidemiology, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland.
Thyroid. 2024 Mar;34(3):295-313. doi: 10.1089/thy.2023.0556. Epub 2024 Feb 16.
Hashimoto thyroiditis (HT) is the most common cause of hypothyroidism in iodine-sufficient areas. Selenium is an essential trace element required for thyroid hormone synthesis and exerts antioxidant effects. Therefore, it may be of relevance in the management of HT. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of selenium supplementation on thyroid function (thyrotropin [TSH], free and total thyroxine [fT4, T4], free and total triiodothyronine [fT3, T3]), thyroid antibodies (thyroid peroxidase antibodies [TPOAb], thyroglobulin antibodies [TGAb], thyrotropin receptor antibody [TRAb]), ultrasound findings (echogenicity, thyroid volume), immune markers, patient-reported outcomes, and adverse events in HT. The study protocol was registered on PROSPERO (CRD42022308377). We systematically searched MEDLINE, Embase, CINHAL, Web of Science, Google Scholar, and the Cochrane CENTRAL Register of Trials from inception to January 2023 and searched citations of eligible studies. Two independent authors reviewed and coded the identified literature. The primary outcome was TSH in patients without thyroid hormone replacement therapy (THRT); the others were considered secondary outcomes. We synthesized the results as standardized mean differences (SMD) or odds ratio (OR), assessed risk of bias using the Cochrane RoB 2 tool, and rated the evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. We screened 687 records and included 35 unique studies. Our meta-analysis found that selenium supplementation decreased TSH in patients without THRT (SMD -0.21 [confidence interval, CI -0.43 to -0.02]; 7 cohorts, 869 participants; = 0%). In addition, TPOAb (SMD -0.96 [CI -1.36 to -0.56]; 29 cohorts; 2358 participants; = 90%) and malondialdehyde (MDA; SMD -1.16 [CI -2.29 to -0.02]; 3 cohorts; 248 participants; = 85%) decreased in patients with and without THRT. Adverse effects were comparable between the intervention and control groups (OR 0.89 [CI 0.46 to 1.75]; 16 cohorts; 1339 participants; = 0%). No significant changes were observed in fT4, T4, fT3, T3, TGAb, thyroid volume, interleukin (IL)-2, and IL-10. Overall, certainty of evidence was moderate. In people with HT without THRT, selenium was effective and safe in lowering TSH, TPOAb, and MDA levels. Indications for lowering TPOAb were found independent of THRT.
桥本甲状腺炎（HT）是碘充足地区导致甲状腺功能减退症的最常见原因。硒是甲状腺激素合成所必需的痕量元素，具有抗氧化作用。因此，它可能与 HT 的治疗相关。我们对随机对照试验（RCT）进行了系统评价和荟萃分析，以评估硒补充剂对甲状腺功能（促甲状腺激素[TSH]、游离和总甲状腺素[fT4、T4]、游离和总三碘甲状腺原氨酸[fT3、T3]）、甲状腺抗体（甲状腺过氧化物酶抗体[TPOAb]、甲状腺球蛋白抗体[TGAb]、促甲状腺素受体抗体[TRAb]）、超声表现（回声、甲状腺体积）、免疫标志物、患者报告的结局和 HT 中的不良事件的影响。研究方案已在 PROSPERO（CRD42022308377）上注册。我们系统地检索了 MEDLINE、Embase、CINHAL、Web of Science、Google Scholar 和 Cochrane 对照试验中心注册库，检索时间从开始到 2023 年 1 月，并检索了合格研究的参考文献。两名独立的作者对确定的文献进行了审查和编码。主要结局是未经甲状腺激素替代治疗（THRT）的患者的 TSH；其他为次要结局。我们将结果综合为标准化均数差（SMD）或比值比（OR），使用 Cochrane RoB 2 工具评估偏倚风险，并使用推荐评估、制定和评估（GRADE）方法评估证据质量。我们筛选了 687 条记录，纳入了 35 项独特的研究。我们的荟萃分析发现，硒补充剂降低了未经 THRT 的患者的 TSH（SMD-0.21[置信区间，CI-0.43 至-0.02]；7 个队列，869 名参与者； = 0%）。此外，TPOAb（SMD-0.96[CI-1.36 至-0.56]；29 个队列；2358 名参与者； = 90%）和丙二醛（MDA；SMD-1.16[CI-2.29 至-0.02]；3 个队列；248 名参与者； = 85%）在有和没有 THRT 的患者中均降低。干预组和对照组的不良事件相当（OR 0.89[CI 0.46 至 1.75]；16 个队列；1339 名参与者； = 0%）。fT4、T4、fT3、T3、TGAb、甲状腺体积、白细胞介素（IL）-2 和 IL-10 无显著变化。总体而言，证据确定性为中等。在未经 THRT 的 HT 患者中，硒在降低 TSH、TPOAb 和 MDA 水平方面是有效和安全的。降低 TPOAb 的指征独立于 THRT。
