Plasma adiponectin levels in women with polycystic ovary syndrome: impact of metformin treatment in a casecontrol study
S. Singh, N. Akhtar & J. Ahmad
Objective: An interaction between adiponectin, steroid synthesis or action and measures of insulin resistance (IR) have been reported in the pathogenesis of polycystic ovary syndrome (PCOS). The present study was done to determine plasma adiponectin concentration (PAC) in women with and without PCOS and to assess its correlation to the hormonal and metabolic parameters including measures of IR. The effect of metformin for 6 months in PCOS was also evaluated.
Patients: In total, 72 selected women were classified as follows: 17 obese (body mass index (BMI)) >25 kg/m2 with PCOS; 19 normal weight (BMI 1822.9 kg/m2 with PCOS; 17 obese BMI >25 kg/m2 without PCOS and 19 normal weight (BMI) 1822.9 kg/m2 without PCOS.
Interventions: Blood samples were collected from all women with PCOS between 0800 and 1100 h, after an overnight fast.
Main outcome measures: Serum level of LH, FSH, TSH, total T4, testerosterone, 17-α-hydroxyprogesterone (17OHP), DHEAS, insulin, adiponectin and glucose. Measures of IR included fasting serum insulin (FSI), glucose-to-insulin ratio, and homeostasis model assessment (HOMA).
Result: Waist-hip ratio (WHR), insulin, and HOMA index were significantly higher in the lower adiponectin group than in the higher adiponectin group. By using stepwise multiple regression analysis, in model 1 (including BMI, FSI, fasting plasma glucose (FPG) with other variables such serum as testerosterone and DHEAS), the weight and contributions from other variables, namely FSI and FPG were significant independent determinants of fasting PAC (adjusted r2=0.66); and in model 2 (including BMI, HOMA, FPG only as an index of IR with other variables such as serum testerosterone, DHEAS), BMI, HOMA, were significant independent determinants of fasting PAC (adjusted r2=0.59). FPG, HOMA Index and FSI were significantly lower after metformin treatment in both obese and non-obese PCOS while adiponectin levels increased significantly.
Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.
Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.