Background and aim
Polycystic ovary syndrome (PCOS) is a complex metabolic and endocrine disorder. The influence of different metabolic and endocrine changes in women with PCOS and their relevance to bone status remains to be documented. Irisin is a newly identified adipo-myokine, which may play a role in the etiopathogenesis of PCOS as well as bone metabolism. The aim of the study was to assess bone mineral density (BMD) and serum irisin level in women with PCOS and to determine BMD relationship with irisin and other hormonal parameters.
Patients and methods
The study enrolled 80 women of reproductive age having PCOS and 15 age-matched and BMI-matched healthy women to serve as controls. A metabolic panel, reproductive hormones, and serum irisin level were measured. In addition, BMD of the spine and femur was also assessed using dual-energy X-ray absorptiometry.
Results
Serum irisin level, fasting insulin, and homeostatic model assessment of insulin resistance were significantly higher in the PCOS group compared with the control group. Receiver operating characteristic curve for serum irisin was done for the PCOS group and the control group and demonstrated that the cut-off value for serum irisin was 0.161 μg /dl. There was also a statistically significant difference between the PCOS group and the control group in BMD of spine and femur, being higher in the PCOS group. Logistic regression analysis has shown that serum irisin level, waist circumference, and fasting serum insulin were predictors for the -score of spine in the PCOS group.
Conclusion
Serum irisin level may be considered as a novel biomarker for PCOS diagnosis. Circulating irisin in PCOS is strongly related to BMD. This suggests that irisin as an adipo-myokine may also be associated with bone metabolism.