Relationship between insulin resistance, plasma apelin and ghrelin levels in the patients with polycystic ovary syndrome

ObjectiveThis study aims to assess the relationship between insulin resistance that we have found through euglycemic clamp test, which is considered as the gold standard test for pa-tients with polycystic ovary syndrome (PCOS) and plasma levels of apelin and ghrelin.Material MethodsA total of 31 applicants to Adnan Menderes University, Medical School, Depart-ment of Internal Medicine, Division of Endocrinology and Metabolism were involved in the study. The working group consisted of 17 PCOS with an average age of 23 ? 4, the control group covered 14 healthy premenopausal women with an average age of 25 ? 1. The poly-cystic ovary syndrome was diagnosed in accordance with diagnosis criteria of the European Society for Human Reproduction and Embryology and American Society for Reproductive Medicine (ESHRE/ASRM 2003).The insulin resistance of all of the patient and control groups was found through eu-glycemic clamp test, which is considered as the gold standard test. A comparison of demo-graphic, anthropometric measures and biochemical parameters was carried out between the patient and control groups.ResultsA statistically significant difference was found among weight (p<0.001), body mass index (p<0.001), body fat percentage (p=0.009), body water rate (p=0.007) and triceps (p<0.001) and subscapular skin fold thickness (p<0.001) in the results of patient group with polycystic ovary syndrome compared with the control group in terms of anthropometric measures. The body mass index, weight, body fat percentage, triceps and subscapular skin fold thickness in patient group were higher than those of the control group, whereas the body water rate was found lower. There was a Ferriman-Gallwey score of more than 8 in the entire patient group, which was found statistically significantly higher, compared to the control group (<0.001).The patient group with polycystic ovary syndrome displayed statistically significant results in terms of fasting insulin level (p=0.001), HOMA-IR (p=0.003), testosterone (p<0.001) and TSH (p=0.001), compared to the control group. The insulin level, HOMA-IR, testosterone and TSH level were found higher in patients with polycystic ovary syndrome than the control group.The M value (amount of metabolized glucose) which is found through euglycemic clamp test was statistically significantly lower in the group with polycystic ovary syndrome, compared to the control group (p<0.001). There was no statistically significant difference between the group with polycystic ovary syndrome and control group in terms of ghrelin level (p>0.05).A meaningful correlation was found between the M value and apelin level in patients with polycystic ovary syndrome, whereas no correlation existed in terms of ghrelin level. While the apelin level increased, the M value decreased.ConclusionsInsulin resistance increases in parallel to an increase in serum apelin level, but the ghrelin level remains the same. It is considered that apelin synthesis increases as a result of an increase in fatty tissue due to insulin resistance, and that a higher plasma apelin level could play a role in etiology in patients with PCOS which is also based on insulin resistance.Keywords: Polycystic ovary syndrome, euglycemic clamp test, insulin resistance, apelin, ghrelin