Changes in Body Composition Are Associated With Changes in Biomakers of Chronic Inflammation, Cardiovascular Disease Risk, and Glucose Sensitivity in Mexican-American Children

Abstract

Excess adiposity is associated with an accumulation of systemic, low-grade inflammation, which has been implicated in the pathophysiology of various diseases. PURPOSE: The hypothesis of this study was that changes in body composition are related to changes on blood lipid profile, insulin resistance, and inflammatory biomarkers in Mexican-American children and the change would be independent of the effect of aerobic exercise (4 days per week, 45 min per day) combined with dietary counseling (1 day per week, 45 min per day). METHODS: Boys and girls (N=173; 13.3±0.1 y) were recruited from a local school and randomly assigned to either an intervention or control group. The participants in the present study self-identified their ethnic group as Mexican-American. Venous blood samples were collected following an overnight fast (>8h) at baseline and 6 months. Plasma concentration of insulin, hsCRP, sCD14, IL-6, and TNF-α were determined by ELISA. Plasma glucose was determined using an automated analyzer and blood lipid profile was determined using an enzymatic method. Insulin resistance scores (HOMA-IR) were calculated. RESULTS: Biomarkers of chronic inflammation, cardiovascular disease, and glucose sensitivity were analyzed using a Linear Mixed Models approach (STATA v. 10.0). We found that there was a significant decrease over time, which was associated with a decrease in body weight (controlled for height): total cholesterol (P=0.01), triglycerides (P<0.001), cLDL (P=0.049), hsCRP (P<0.001), insulin (P<0.001), and HOMA-IR (P<0.001). There was a significant increase in HDL (P<0.001), which was negatively associated with a decrease in body weight. When the model was run with tricep skin fold (measure of adiposity) in place of height and weight, a significant change was also found for found for these same variables (p <0.001). No significant change over time was found for IL-6 or TNF-α, regardless of a change in weight or tricep skinfold. CONCLUSION: Our results showed that changes in selected biomarkers of inflammation and cardiovascular health risk were related to changes in body composition of Mexican-American children. This change was independent of a moderate exercise/dietary intervention.