The cut-off value for HOMA-IR discriminating the insulin resistance based on the SHBG level in women with polycystic ovary syndrome.

Introduction: The study aimed to estimate the cut-off value for homeostatic model assessment for insulin resistance (HOMA-IR) discriminating the insulin resistance based on the sex hormones binding globulin (SHBG) level in women with polycystic ovary syndrome (PCOS). Materials and methods: Data from medical records of 854 Caucasian women diagnosed with PCOS were analyzed. Anthropometric data, fasting plasma glucose, insulin and SHBG levels were measured. HOMA-IR was calculated with a standard formula. The cut-off value was calculated using receiver-operating characteristics. Results: Circulating SHBG levels below the normal range (26.1 nmol/L) were found in 25.4% of study participants. This subgroup had a significantly higher BMI, fasting glucose and insulin concentrations and HOMA-IR values. Empirical optimal cut-off values for HOMA-IR corresponding to low SHBG levels was ≥2.1 [area under the curve (AUC) 0.73, accuracy 0.65, sensitivity 72.3%, specificity 63.1%, positive predictive value (PPV) 40.0%, negative predictive value (NPV) 87.0%]. Conclusions: Our study suggests that the cut-off point for HOMA-IR discriminating the insulin resistance based on the SHBG level, in young Caucasian women with polycystic ovary syndrome is 2.1, and is consistent with the cut-off value adopted by the European Group for the Study of Insulin Resistance (above 2.0).

Prediction of Insulin Resistance and Impaired Fasting Glucose Based on Sex Hormone-Binding Globulin (SHBG) Levels in Polycystic Ovary Syndrome.

OBJECTIVE: Decreased synthesis of sex hormone-binding globulin (SHBG) related to hyperinsulinemia is one of the disturbances characteristic of polycystic ovary syndrome (PCOS). Hyperinsulinemia is a compensatory mechanism for liver insulin resistance (IR); thus, SHBG may be considered as a surrogate marker of liver IR. Therefore, this study aimed to assess the prediction of IR and impaired fasting glucose (IFG) based on SHBG levels in women with PCOS. METHODS: This analysis included data retrieved from medical records of 854 patients with PCOS hospitalized in the Gynecological Endocrinology Clinic from 2012 to 2019. Data including anthropometric parameters, fasting plasma glucose, insulin, and SHBG levels were analyzed. BMI and HOMA-IR were calculated with standard formulas. RESULTS: IFG and IR assessed based on HOMA-IR values > 2.0 were found in 19.5% and 47.8% of the study group, respectively. Empirical optimal cutoff values for SHBG levels were ≤41.5 nmol/L typical for IR (AUC 0.711, sensitivity 61.1%, specificity 71.6%, positive predictive value (PPV) 70.7%, and negative predictive value (NPV) 62.1%). The probability of insulin resistance occurrence for SHBG concentration 26.1 nmol/L (the lower normal range) was 61.6% (95% CI: 57.4%-65.8%). The SHBG concentration of 36.4 nmol/L and 8.1 nmol/L was related to a 10% and 20% probability of IFG, respectively. CONCLUSION: In conclusion, this is the first study estimating the probability of liver IR and IFG occurrence based on SHBG levels in women with PCOS. Despite the low sensitivity, SHBG level below 42 nmol/L should cause closer monitoring for the fatty liver and prediabetes.

Zinc, copper, sirtuin 1 concentration, and glucose metabolism parameters in the blood of women with polycystic ovary syndrome.

The aim of this study was to assess concentration of zinc (Zn), copper (Cu), and sirtuin 1 (SIRT1) in serum of women with polycystic ovary syndrome (PCOS) and their relationships with glucose metabolism parameters. The study included 76 women with PCOS aged between 17 and 39 years old. The blood was collected according to the routine procedure during the follicular phase. Zn and Cu concentrations were performed by flame atomic absorption spectrometry (FAAS). Glucose concentration was estimated by colorimetric methods. Insulin (INs) concentration was determined by enzyme-linked immunosorbent assay. SIRT1 concentration was determined using commercial test. We found higher Cu concentration and Cu/Zn value in the serum of women with PCOS with overweight/obesity. Early stage of insulin resistance (IR) in the group of women with PCOS affected on higher Cu concentration and Cu/Zn value. However, increased value of body mass index, waist-hip ratio and homeostatic model assessment of insulin resistance (HOMA-IR) was not associated with changes in Zn and SIRT1 concentration. Further disturbances in glucose metabolic parameters in the blood of women with PCOS were intensified by overweight/obesity and IR. Overweight/obesity and IR in the women with PCOS increase disorders in Cu homeostasis and glucose metabolism parameters.