Association of decreased C1q/tumor necrosis factorrelated protein-5 levels with metabolic and hormonal disturbance in polycystic ovary syndrome

OBJECTIVE: C1q/tumor necrosis factor-related protein-5 (CTRP5) is a novel peptide hormone involved in the metabolism of energy regulation. Polycystic ovary syndrome (PCOS), which is a reproductive and metabolic disorder, is associated with insulin resistance. The aim of the current study was to compare circulating levels of CTRP5 in women with and without PCOS and to investigate possible associations between CTRP5 and metabolic-hormonal parameters. MATERIAL AND METHODS: The present cross-sectional study contained 80 women with PCOS and 80 age and body mass index-matched women without PCOS. Circulating levels of CTRP5 were calculated using an enzyme-linked immunosorbent assay. We also measured hormonal and metabolic parameters. RESULTS: Patients with PCOS had lower levels of circulating CTRP5 compared with women without PCOS (6.90±2.64 vs 11.73±3.66 ng/mL, p<0.001). CTRP5 was negatively correlated with insulin resistance, free-androgen index, and body mass index in both the PCOS and control groups. Moreover, patients with PCOS who had insulin resistance showed lower circulating CTRP5 levels compared with those without insulin resistance. In both the control and PCOS groups, overweight subjects had lower circulating levels of CTRP5 compared with participants of normal weight. Logistic regression analyses indicated that subjects in the lowest tertile for CTRP5 level had higher risk for PCOS compared with those in the highest tertile of CTRP5. CONCLUSION: Decreased circulating levels of CTRP5 were associated with higher risk of PCOS, as well as having metabolic disturbance among women with PCOS.