Purpose

Though most of the observational studies have shown that metformin can reduce serum thyroid stimulating hormone (TSH) level in patients of hypothyroidism with diabetes or polycystic ovarian disease, randomised controlled trials are sparse. The primary objective of this study was to evaluate the effect of metformin on thyroid function tests (TSH, free T4, and free T3) in patients with subclinical hypothyroidism (SCH).

Methodology

In this open label, parallel arm, randomised controlled trial, 60 patients of SCH (TSH 5.5–10 mIU/L) were randomised to either metformin group (1500 mg/day) or control group.

Result

A total of 46 patients (23 in each group) completed the study and no significant difference in serum TSH, free T4 or free T3 was found in between the 2 groups. Neither there was any significant change in serum TSH, free T4 or free T3 (pre and post 6 months) within the individual groups. However, the rate of normalisation of serum TSH in patients with negative thyroid antibody was significantly higher than patients with positive thyroid antibody (71.4% vs. 18.8%; P = 0.026) in metformin group in post hoc analysis. Fasting plasma glucose, serum high-density lipoprotein and indices of insulin sensitivity significantly improved in metformin group. Four patients (17%) had mild gastrointestinal adverse effects in the metformin group.

Conclusion

We did not find any significant change in thyroid function test in patients with SCH with metformin therapy.

中文翻译：

---

二甲双胍对亚临床甲状腺功能减退症患者甲状腺功能检查的影响：一项开放性随机对照试验

目的

尽管大多数观察性研究表明，二甲双胍可以降低患有糖尿病或多囊卵巢疾病的甲状腺功能低下患者的血清甲状腺刺激激素（TSH）水平，但随机对照试验很少。这项研究的主要目的是评估二甲双胍对亚临床甲状腺功能减退症（SCH）患者甲状腺功能测试（TSH，游离T4和游离T3）的影响。

方法

在这项开放标签的平行臂随机对照试验中，将60例SCH（TSH 5.5-10 mIU / L）患者随机分为二甲双胍组（1500 mg /天）或对照组。

结果

共有46位患者（每组23位）完成了研究，两组之间的血清TSH，游离T4或游离T3差异无统计学意义。在各个组中，血清TSH，游离T4或游离T3（6个月前和6个月后）均无显着变化。但是， 在事后分析中，二甲双胍组甲状腺抗体阴性的患者血清TSH正常化率显着高于甲状腺抗体阳性的患者（71.4％vs. 18.8％；P = 0.026）。二甲双胍组的空腹血糖，血清高密度脂蛋白和胰岛素敏感性指数显着改善。二甲双胍组中有4例（17％）有轻度胃肠道不良反应。

结论

在二甲双胍治疗的SCH患者中，我们未发现甲状腺功能检查有任何显着变化。