Inflammatory Markers, Insulin Resistance, And Metabolic Syndrome Among Overweight Or Obese School-Aged Children

【Objectives】To examine the degree of inflammatory markers in normal, overweight, and obese individuals, and these serum inflammatory markers in relation to insulin resistance in overweight or obese school-aged children.【Subjects and Methods】Six primary schools with the prevalence rates of overweight + obesity greater than 10% were randomly chosen from urban district of Chongqing. Two classes were randomly chosen for the study from each grade, i.e. a total of 48 classes were recruited in this study. According to the criteria of overweight and obesity recommended by International Obesity Task Force (IOTF), 54 were obese children were identified, and 82 overweight and 73 normal children were randomly selected from corresponding sub-segments. Anthropometric measures and plasma biochemical markers (including insulin, glucose, and lipid profiles) were measured using standard methods. Serum levels of high-sensitivity C-reactive protein (hs-CRP), interleukin 6 (IL-6) and tumor necrosis factorα(TNF-α) were measured using ELISA. The homeostasis model assessment (HOMA) index was calculated to assess insulin resistance.【Results】Serum values of hs-CRP, IL-6, TNF-α, diastolic blood pressure (DBP), Triglyceride (TG), low-density lipoprotein (LDL), insulin (INS), and HOMA (all p<0.0001) were significant different among these three groups. Except for TNF-α, the highest values were observed in obese group. There were no significant differences in serum concentrations of glucose and high-density lipoprotein (HDL) among groups. The prevalent rates of insulin resistance, i.e. HOMA>2 were 8.62%, 28.33%, and 46.15% for normal, overweight, and obese children, respectively. Significant differences among normal, overweight, and obese groups were identified (x2=18.77, P<0.0001). Children with insulin resistance (HOMA>2) had higher TG, hs-CRP and lower HDL than the other children (HOMA≤2) (P<0.05 for all). TG and hs-CRP were found to be significant factors for HOMA index with adjustment for sex and age. However, after adjusting for Body mass index (BMI), the association between hs-CRP and HOMA was replaced by BMI (F=53.23, P≤0.0001). But the association between TG and HOMA was persisted (F=5.34, P=0.0223). 【Conclusions】Our results indicated that dyslipidemia and inflammation presented in overweight or obese children. With increased weight gain, dyslipidemia, inflammation, and insulin resistance became more serious. Inflammation in obese children might serves as one of the mechanisms causing insulin resistance observed in obese individuals. 【Objective】To explore the rates of metabolic syndrome (MS) in normal, overweight, and obese school-aged children and to understudy the underline mechanisms of MS in terms of inflammatory factors.【Methods】Six primary schools with the prevalence rates of overweight + obesity greater than 10% were randomly chosen from urban district of Chongqing. Two classes were randomly chosen for the study from each grade, i.e. a total of 48 classes were recruited in this study. According to the criteria of overweight and obesity recommended by International Obesity Task Force (IOTF), 54 were obese children were identified, 82 overweight and 73 normal children were randomly selected from corresponding sub-segments. We classified those subjects into three groups: normal (77) and non-MS (109) and MS (23). The criteria we used to diagnose the metabolic syndrome were modification of the National Cholesterol Education Program(NCEP)ATPⅢaccording to Cook's criteria. Anthropometric measures were measured by professional persons using routine methods. Serum biochemical markers (including triglycerides, HDL, cholesterol, LDL, glucose and insulin) were determined by Clinical Analyzer (Siemens ADVIA 2400) using standard methods. Serum levels of high-sensitivity C-reactive protein (hs-CRP), interleukin 6 (IL-6) and tumor necrosis factorα(TNF-α) were analyzed using commercial ELISA kits.【Results】The rates of MS were 27.78%, 9.77% and 0% respectively in obese, overweight and normal school-aged children. The rates were significantly different among normal, overweight, and obese children (P<0.01). Serum values of hs-CRP and IL-6 were significant different (P<0.01)among the normal, non-MS, and MS groups after adjusting for both sex and age. The highest levels of the three measures were found in MS children, and lowest in normal children. However, there were no significant differences in serum concentrations of TNF-αamong the three-group children.【Conclusion】Our results indicate that overweight and/or obesity increases the rate of metabolic syndrome in school-aged children. Low-grade inflammation exists in both overweight and obese children, and may increases the risk of metabolic syndrome. Elevated rate of MS in obese children may due to increased hs-CRP and IL-6. Both have a potential for using as a measure of the inflammatory component of MS.