No association between cortisol, parameters of zinc, and insulin resistance in obese women

Objective: Evaluate the association between cortisol, zinc parameters and insulin resistance in obese women. Methods: Case-control study was conducted, enrolling women aged between 20 and 50 years old, who were divided into case group (n=45) and control group (n=42). The dietary zinc intake was assessed by 3-day food records using Nut Win software version 1.5. Zinc concentrations in plasma, erythrocytes, and urine were determined by inductively coupled plasma optical emission spectrometry. Serum glucose and fasting insulin levels were determined by colorimetry and chemiluminescence, respectively. Serum cortisol concentrations and plasma glycated hemoglobin levels were determined by electro chemiluminescence and ion exchange chromatography, respectively. Insulin resistance was assessed by the HOMA-IR and HOMA2 indexes. Data were analyzed using the statistical software SPSS for Windows 20.0. Results: Serum cortisol concentrations did not present statistical difference between the groups (p> 0.05). Obese women had reduced plasma and erythrocyte zinc concentrations, when compared to the control group (p <0.05).There was no statistically significant difference between the groups in the glucose and fasting insulin levels, and HOMA-IR and HOMA 2 indexes (p> 0.05). Conclusions: In addition, multiple linear regression analysis between serum cortisol, zinc parameters, and glycemic control parameters did not demonstrate the influence of this hormone on zinc metabolism and insulin resistance.