Serum sex hormone-binding globulin levels show too much variability to be used effectively as a screening marker for insulin resistance in women with polycystic ovary syndrome

Abstract

To evaluate the relationship between serum sex hormone-binding globulin (SHBG) and parameters of insulin sensitivity in women with polycystic ovary syndrome (PCOS) and controls, and determine the feasibility of using SHBG levels to predict insulin resistance. Evaluation of a prospectively collected database. University reproductive center. A total of 21 women with PCOS and 17 controls. Oral glucose tolerance test. Correlations of serum SHBG and parameters of insulin sensitivity. [1] Among all participants, SHBG levels indicated a correlation between the fasting glucose-to-insulin (GI) ratio and the quantitative insulin sensitivity check index (QUICKI). Participants with PCOS demonstrated significant correlations of SHBG and fasting GI ratio, 1-hour postglucola insulin levels, and random 17-hydroxyprogesterone (17ohP4) levels. Among controls, SHBG and fasting serum glucose and 2-hour postglucola serum glucose levels were associated. [2] Participants with PCOS and lean controls exhibited different glucose and insulin responses to 75 g of glucose at 1 and 2 hours postchallenge, resulting in paradoxically similar GI ratios. [1] Although certain parameters of insulin status and serum SHBG demonstrated statistically significant correlation coefficients, these relationships are weak and SHBG cannot be used as a predictor of insulin resistance. [2] The post-glucose load GI ratio cannot be used to determine the magnitude of insulin resistance.