Associations between sex hormone binding globulin and metabolic syndrome parameters in premenopausal obese women

Background and Aims: The aim of this study was to determine sex hormone binding globulin (SHBG) concentrations in premenopausal obese women and to evaluate the relationships between sex hormones and features of the metabolic syndrome (MetS). Settings and Design: Retrospective cross-sectional analysis was carried out on 350 obese patients aged 25 to 69 years referred to the Department of Endocrinology, Pamukkale University in 2002-2003. Materials and Methods: 125 premenopausal euthyroid patients were eligible for this study. Subjects were divided into two groups according to the body mass index (BMI): Group I, women with BMI < 30 kg/m 2 (n = 17) and Group II,, women with BMI ≥ 30 kg/m 2 (n = 108). Median SHBG concentration of Group I was 50.1 nmol/L. Group II was divided into two subgroups according to the median SHBG concentration of Group I: subjects with high SHBG levels (SHBG concentration ≥ median level of the control group, i.e ≥ 50.1 nmol/L) and subjects with low SHBG levels (< 50.1 nmol/L). All statistical analyses were performed using SPSS 9.0 software (SPSS Inc.). Results: No significant difference was found in mean age between the low and high SHBG groups. The low SHBG group was significantly heavier, and with higher waist circumference than the high SHBG group. In the low SHBG group, fasting glucose, postprandial glucose and gamma glutamyl transferase (GGT) and free androgen index (FAI) were significantly higher. Lipid profile, blood pressure, uric acid, insulin and HOMA were found similar between two groups. Linear regression analyses revealed that body mass index and FAI were significant, being independent predictors of SHBG concentrations in premenopausal women. (r = 0.365, r square = 0.134). Conclusions: It is concluded that low SHBG concentrations may indicate visceral obesity and glucose intolerance in premenopausal women