Metformin does not improve insulin sensitivity over hypocaloric diets in women with polycystic ovary syndrome: a systematic review of 12 studies

Abstract

Objective

To improve insulin action, most clinicians prescribe Metformin in patients with insulin resistance (IR). Women with polycystic ovary syndrome (PCOS), in which IR is an important physiopathological mechanism, treatment with Metformin and specialized diets have been suggested to reduce the patient’s IR. However, numerous studies have demonstrated conflicting results with respect to supplementing a diet with Metformin. Therefore, we conducted a meta-analysis to determine if Metformin provides a benefit in conjunction with hypocaloric diets to improve insulin sensitivity in PCOS women.

Methods

PubMed, SCOPUS, LILACS, and EBSCO databases and retrieved studies’ bibliographies were searched for prospective studies that investigated the effect between Metformin and hypocaloric diets in PCOS women until April 2020. Pre- and post-intervention values for fasting plasma glucose (FPG), fasting plasma insulin (FPI), and IR indices (HOMA1-IR, ISI, and QUICKI) were extracted. Using Comprehensive Meta-Analysis software, the pooled standard difference in the means (SDM) and 95%CIs were calculated.

Results

11 publications (12 studies) were selected. There was not a benefit of adding Metformin to a hypocaloric diet with respect to FPG (SDM= −0.17; 95%CI: −0.48–0.14, p = .28) and FPI (SDM = 0.16; 95%CI: −0.24–0.55, p = .45). None of the IR indices also demonstrated any benefit of using Metformin when a diet intervention was implemented (HOMA1-IR: SDM = 0.28; 95%CI: −0.27–0.84, p = .315; ISI: SDM = 0.344; 95%CI: −0.17–0.85, p = .186; QUICKI: SDM= −0.01; 95%CI: −0.42–0.41, p = .968).

Conclusion

Here, we determined that adding Metformin to hypocaloric diets did not improve serum glucose or insulin concentrations as well as IR in PCOS women.

与低热量饮食相比, 二甲双胍不能改善多囊卵巢综合征女性的胰岛素敏感性：12项研究的系统评价 摘要

目的：为了改善胰岛素的作用, 大多数临床医生给胰岛素抵抗（IR）患者服用二甲双胍。多囊卵巢综合征（PCOS）患者的胰岛素抵抗是其重要的生理病理机制, 二甲双胍治疗和特殊饮食可降低患者的IR。然而, 许多研究表明, 在饮食中补充二甲双胍的结果是相互矛盾的。因此, 我们进行了一项meta分析, 以确定二甲双胍与低热量饮食联合应用是否有益于改善PCOS患者的胰岛素敏感性。

方法：检索PubMed、SCOPUS、LILACS和EBSCO数据库以及在检索到的研究文献中搜索前瞻性研究, 这些研究截止到2020年4月, 调查了二甲双胍和低热量饮食对PCOS患者的影响。测定干预前后空腹血糖（FPG）、空腹血浆胰岛素（FPI）和IR指数（HOMA1-IR、ISI和QUICKI）。应用综合Meta分析软件计算了合并标准差（SDM）和95%CI。

结果：选择了11篇出版物（12项研究）。 在低热量饮食中添加二甲双胍对FPG（SDM=-0.17；95%CI：-0.48–0.14, p=0.28）和FPI（SDM=0.16；95%CI：-0.24–0.55 , p=0.45）没有益处。当进行饮食干预时, 没有任何IR指数证明应用二甲双胍有任何好处（HOMA1-IR：SDM=0.28；95%CI：-0.27–0.84, p=0.315；ISI：SDM=0.344；95%CI： -0.17–0.85, p=0.186；QUICKI：SDM=-0.01；95%CI：-0.42–0.41, p=0.968）。

结论：在这里, 我们确定在低热量饮食中添加二甲双胍并不能改善PCOS患者的血糖或胰岛素浓度以及IR。

Keywords:

• Biguanide
• insulin resistance
• lifestyle
• meta-analysis
• weight loss

Acknowledgments

The authors express their gratitude to Mtro. Ricardo Villegas Tovar, Coordinator of Scientific Production and International Visibility, BUAP.

Disclosure statement

The authors report no conflict of interest.

Data availability statement

Data sharing is not applicable to this article as no new data were created or analyzed in this study.

Additional information

Funding

This study was supported by grants from Vicerrectorıa de Investigacion, Benemerita Universidad Autonoma de Puebla, Mexico (GOMM-SAL18-I). The funders had no role in the study’s design, data collection or analysis, decision to publish, or preparation of the manuscript.