Comparison of two insulin sensitizers, metformin and myo-inositol, in women with polycystic ovary syndrome (PCOS)

Abstract

Insulin resistance (IR) plays a pivotal role in PCOS. Insulin-sensitizer agents such as metformin and inositols have been shown to improve the endocrine and metabolic aspects of PCOS. The purpose of this study is to compare their effects on the clinical and metabolic features of the women with PCOS. Fifty PCOS women with IR and/or hyperinsulinemia were randomized to treatment with metformin (1500 mg/day) or myo-inositol (4 g/day). IR was defined as HOMA-IR >2.5, while hyperinsulinemia was defined as a value of AUC for insulin after a glucose load over the cutoff of our laboratory obtained in normal women. The Matsusa Index has been calculated. The women have been evaluated for insulin secretion, BMI, menstrual cycle length, acne and hirsutism, at baseline and after 6 months of therapy. The results obtained in both groups were similar. The insulin sensitivity improved in both treatment groups. The BMI significantly decreased and the menstrual cycle was normalized in about 50% of the women. No significant changes in acne and hirsutism were observed. The two insulin-sensitizers, metformin and myo-inositol, show to be useful in PCOS women in lowering BMI and ameliorating insulin sensitivity, and improving menstrual cycle without significant differences between the two treatments.

Chinese abstract

胰岛素抵抗 (IR) 在PCOS中起关键作用。胰岛素增敏剂如二甲双胍和肌醇在改善PCOS的内分泌和代谢方面已显示出有益作用。本研究的目的是比较其对PCOS患者的临床和代谢特征的影响。将50名具有IR和/或高胰岛素血症的PCOS妇女随机分配为两组, 分别使用二甲双胍 (1500mg/天) 或肌醇 (4g/天) 治疗。 IR定义为胰岛素抵抗指数 (HOMA-IR) > 2.5, 而高胰岛素血症定义为糖耐量试验中胰岛素的AUC值高于我们实验室从正常妇女中获得的切值。同时计算Matsuda胰岛素敏感性指数。在治疗6个月后, 对这些妇女的胰岛素分泌, BMI, 月经周期, 痤疮和多毛症情况进行了评估, 比较治疗前后的情况。两组的结果相似。两个治疗组对于胰岛素敏感性均有改善。约50％的妇女的BMI显著降低, 月经周期逐渐规律。痤疮和多毛的症状改善不明显。结论提示: 两种胰岛素增敏剂, 二甲双胍和肌醇, 均可用于PCOS妇女降低BMI和改善胰岛素敏感性, 并改善月经周期, 两种治疗之间没有显著性差异。

Keywords:

• Androgens
• amenorrhea
• insulin resistance
• insulin sensitizer
• polycystic ovary syndrome

Declaration of interest

The authors report no conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.