Unit of Internal Medicine and Endocrinology, Fondazione Salvatore Maugeri IRCCS, ISPESL Laboratory for Endocrine Disruptors, University of Pavia, Pavia, Italy.
Clin Endocrinol (Oxf). 2011 Sep;75(3):378-81. doi: 10.1111/j.1365-2265.2011.04042.x.
Metformin is widely used for the treatment of type 2 diabetes. Growing evidence supports the beneficial effects of metformin also in patients with polycystic ovary syndrome (PCOS). It was recently reported that metformin has a TSH-lowering effect in hypothyroid patients with diabetes being treated with metformin.
Aim of this study was to evaluate the effect of metformin treatment on the thyroid hormone profile in patients with PCOS.
Thirty-three patients with PCOS were specifically selected for being either treated with levothyroxine for a previous diagnosis of hypothyroidism (n = 7), untreated subclinically hypothyroid (n = 2) or euthyroid without levothyroxine treatment (n = 24) before the starting of metformin. The serum levels of TSH and FT(4) were measured before and after a 4-month period of metformin therapy.
Thyroid function parameters did not change after starting metformin therapy in euthyroid patients with PCOS. In the 9 hypothyroid patients with PCOS, the basal median serum levels of TSH (3·2 mIU/l, range = 0·4-7·1 mIU/l) significantly (P < 0·05) decreased after a 4-month course of metformin treatment (1·7 mIU/l, range = 0·5-5·2 mIU/l). No significant change in the serum levels of FT4 was observed in these patients. The TSH-lowering effect of metformin was not related to the administered dose of the drug, which was similar in euthyroid as compared with hypothyroid patients with PCOS (1406 ± 589 vs 1322 ± 402 mg/day, respectively; NS).
These results indicate that metformin treatment has a TSH-lowering effect in hypothyroid patients with PCOS, both treated with l-thyroxine and untreated.
二甲双胍广泛用于治疗 2 型糖尿病。越来越多的证据支持二甲双胍对多囊卵巢综合征（PCOS）患者也有益处。最近有报道称，在接受二甲双胍治疗的糖尿病伴甲状腺功能减退症患者中，二甲双胍具有降低 TSH 的作用。
本研究旨在评估二甲双胍治疗对 PCOS 患者甲状腺激素谱的影响。
专门选择了 33 名 PCOS 患者，他们之前被诊断为甲状腺功能减退症（n = 7）、未经治疗的亚临床甲状腺功能减退症（n = 2）或未经左旋甲状腺素治疗的甲状腺功能正常（n = 24），在开始使用二甲双胍前。在开始使用二甲双胍 4 个月后，测量了患者的 TSH 和 FT4 血清水平。
甲状腺功能参数在甲状腺功能正常的 PCOS 患者开始使用二甲双胍治疗后没有变化。在 9 名 PCOS 伴甲状腺功能减退症患者中，基础血清 TSH 中位数（3·2 mIU/L，范围 = 0·4-7·1 mIU/L）在使用二甲双胍治疗 4 个月后显著（P < 0·05）降低（1·7 mIU/L，范围 = 0·5-5·2 mIU/L）。这些患者的血清 FT4 水平没有明显变化。二甲双胍的 TSH 降低作用与药物的给药剂量无关，在甲状腺功能正常和甲状腺功能减退症的 PCOS 患者中相似（分别为 1406 ± 589 与 1322 ± 402 mg/天；NS）。
这些结果表明，二甲双胍治疗对接受或未接受 l-甲状腺素治疗的 PCOS 伴甲状腺功能减退症患者均具有降低 TSH 的作用。
