Impact of metformin on C-reactive protein levels in women with polycystic ovary syndrome: a meta-analysis.

Yong Chen,Qiguang Wang,Dan Xu,Hongli Deng,Ningsha Li,Sheying Wang,Meng Li,Lihua Chen

doi:10.18632/oncotarget.16019

Abstract

The impact of the recommended first-line treatment with metformin on C-reactive protein (CRP) levels in patients with polycystic ovary syndrome (PCOS) is still controversial. We conducted a meta-analysis of studies reporting the impact of metformin on serum CRP levels in women with PCOS. The weighted mean differences (WMDs) and the corresponding 95% confidence intervals (CIs) were used to assesse the effects. GRADE approach was used to assesse the quality of the evidence. A total of 20 studies that included 433 women with PCOS were analyzed. CRP levels significantly decreased after metformin treatment (WMD = -1.23mg/L, 95%CI: -1.65 to -0.81, I2 = 93% and P < 0.001 for heterogeneity). The decreased levels of CRP were observed both in lean (BMI<25 kg/m2) and obese (BMI>25 kg/m2) patients. Interestingly, the degree of decreased CRP levels was not depended on metformin dosage, but more significantly in patients treated beyond 6 months (WMD≥6months = -1.47mg/L vs. WMD<6months = -0.94 mg/L). Decreased CRP levels are not associated with the status of IR and androgen in patients with PCOS. However, the quality of evidence was very low because of the limitations and inconsistency of the included studies. Therefore, metformin shows the potential effects on CRP levels in women with PCOS. However, considering the very low quality of evidence for the analysis, the effect of metformin on CRP levels are still very uncertain, and large-scale randomized-controlled study is needed to ascertain the long-term effects of metformin in PCOS.

Highlights

Polycystic ovary syndrome (PCOS) is a common endocrinopathy with various clinical features
Fifteen articles [12, 16,17,18,19,20,21,22,23,24,25,26,27,28,29] representing 433 participating women with PCOS were identified as suitable literature for this meta-analysis
The quality of the evidence for all outcomes should be rated as being very low. In this meta-analysis, we investigated whether metformin decreased C-reactive protein (CRP) levels in women with PCOS

Summary

Introduction

Polycystic ovary syndrome (PCOS) is a common endocrinopathy with various clinical features. According to criteria from Rotterdam [1], the National Institute of Health (NIH) [2], and the Androgen Excess and PCOS Society in 2006 [3], the key characteristics features of PCOS are clinical or biochemical hyperandrogenism, menstrual irregularity, and an ultrasound picture of PCO. Obesity and insulin resistance (IR) are not included in these diagnostic criteria, 61%-76% of women with PCOS are overweight [4], and IR is seen in 95% of obese and 65% of lean women with PCOS [5]. PCOS is related to low-grade chronic inflammation [6, 7]. The C-reactive protein (CRP), an acute-phase protein produced mainly by hepatocytes, plays an important role in low-grade chronic inflammation and www.impactjournals.com/oncotarget

Methods

Results

Conclusion