Role of cortisol in the formation of metabolic syndrome in children: literature review and own observations

Background. The issue of the pathogenetic influence of cortisol on the development of metabolic syndrome (MS) in children is considered. The above-threshold values of cortisol are proposed to be taken as a marker of MS. The purpose was to study the relationship between blood cortisol and MS components in children. Materials and methods. We have examined 44 children with MS (study group; waist circumference > 90th percentile of the distribution according to age and sex) and 14 children without signs of MS (controls). The children of the study groups did not differ in age and gender. Anthropometric parameters (body weight, height, body mass index, neck, waist, and hip circumferences, waist/hip circumference index), blood cortisol and leptin, blood lipid and carbohydrate spectrum (total cholesterol, high- and low-density lipoprotein cholesterol, triglycerides, blood glucose, and insulin, HOMA-IR and glucose/insulin indices) were evaluated. The measurement of blood pressure with the calculation of the average level was conducted three times. The diagnosis of MS was formed according to the IDF guidelines, 2007. Results. It was found that the level of blood cortisol in children with MS (362.9 (255.5–634.1) µg/l) was 37.9 % lower than in controls (р > 0.05). The frequency of the above-threshold blood cortisol values in children of both groups was 31.8 and 50.0 %, respectively (р > 0.05). The study of dependence using the Spearman’s rank correlation coefficient between blood cortisol and anthropometric parameters (rmax = 0.16; p > 0.05), lipids (rmax = 0.4; р > 0.05), carbohydrate metabolism (rmax = 0.26; р > 0.05), and blood leptin (r = 0.19; р > 0.05) did not reveal any significance. A significant correlation was found between cortisol and systolic blood pressure. Conclusions. In children with MS, there was no significant difference in the level of blood cortisol compared to those without MS criteria. The association of blood cortisol and MS criteria other than systolic blood pressure has not been found. Although cortisol is important in the formation of systolic blood pressure, it cannot serve as a marker of MS in children since it is not a criterion-forming sign of MS.