title: Impact of Treatment with Metformin on Adipocytokines in Patients with Polycystic Ovary Syndrome: A Meta-Analysis.
abstract: BACKGROUND
  Metformin is effective for the treatment of polycystic ovary syndrome, but conflicting results regarding its effect on adipocytokine levels (adiponectin, resistin, visfatin, and leptin) in patients with polycystic ovary syndrome receiving metformin treatment have been reported. To provide high-quality evidence about the effect of metformin treatment on adipocytokines in patients with polycystic ovary syndrome, relevant studies that assessed the levels of adipocytokines (adiponectin, resistin, visfatin, and leptin) in patients with polycystic ovary syndrome receiving treatment with metformin administration were reviewed and analyzed.
  
  
  METHODS
  A literature search was conducted in the SCI, PUBMED, EMBASE, and Elsevier databases, and personal contact was made with the authors. Standard mean differences and 95% confidence intervals were calculated and combined appropriately. To ensure synthesis of the best available evidence, sensitivity analyses were performed.
  
  
  RESULTS
  A total of 34 data sets were included in 4 different outcomes, involving 744 women with polycystic ovary syndrome and adipocytokine levels measured both before and after metformin administration. Metformin treatment was associated with significantly elevated serum adiponectin concentrations (standard mean differences [95% confidence interval], -0.43 [-0.75 to -0.11]) and decreased serum leptin concentrations (0.65 [0.26 to 1.04]), whereas no significant difference in resistin level (-0.01 [-0.49 to 0.45]) or visfatin level (-0.04 [-1.55 to 1.46]) was found.
  
  
  CONCLUSIONS
  Metformin administration was associated with increased serum adiponectin concentrations and decreased serum leptin levels. Further study is needed to elucidate whether this apparent effect decreases the incidence of type 2 diabetes and other metabolic diseases in patients with polycystic ovary syndrome later in life.
authors.affiliation: Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Kong
authors.affiliation: Department of Otolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Xun
authors.initials: X
authors.lastname: Niu
authors.affiliation: Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Tianshu
authors.initials: T
authors.lastname: Zeng
authors.affiliation: Department of Epidemiology and Biostatistics, and the Ministry of Education Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Meixia
authors.initials: M
authors.lastname: Lu
authors.affiliation: Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Lulu
authors.initials: L
authors.lastname: Chen
mesh_terms: D052242:Adiponectin / Q000097:blood*; D016207:Cytokines / Q000097:blood; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D020738:Leptin / Q000097:blood*; D008687:Metformin / Q000008:administration & dosage* / Q000627:therapeutic use; D054409:Nicotinamide Phosphoribosyltransferase / Q000097:blood; D011085:Polycystic Ovary Syndrome / Q000097:blood / Q000188:drug therapy*; D052243:Resistin / Q000097:blood; D016896:Treatment Outcome
chemical_list: C499918:ADIPOQ protein, human; D052242:Adiponectin; D016207:Cytokines; D020738:Leptin; C499624:RETN protein, human; D052243:Resistin; D008687:Metformin; D054409:Nicotinamide Phosphoribosyltransferase; C085455:nicotinamide phosphoribosyltransferase, human