Changes In Red Blood Cell Distribution Width And Inflammatory Markers Of Children With Simple Obesity

Background and objectives:Childhood simple obesity,a nutritional disorder caused by multiple factors,adversely affects the mental health,growth and development of children as well as their academic performance.Closely related to the development of type 2 diabetes,dyslipidemia,hypertension,hyperuricemia,fatty liver as well as many other chronic metabolic diseases,it has become a risk factor for cardiovascular and cerebrovascular diseases.The incidence of obesity has shown a continuous increase worldwide and it has been recognized as a serious public health problem.The pathogenesis of obesity is complex,and the chronic low-grade inflammatory state of obesity plays an important role in the development of insulin resistance and other related complications,therefore,it always remains as a hot spot for research.Red blood cell distribution width(RDW),as an item of complete blood component count,is a parameter that reflects the heterogeneity of red blood cell volume,i.e.the higher the RDW value,the more heterogeneous the red blood cell volume size.Many studies have found that besides anemia,increased RDW can also be seen in various inflammatory diseases,such as cancer,rheumatic diseases,diabetes,atherosclerosis(cardiovascular disease),autoimmune diseases,etc.Inflammation and oxidative stress may be potential biological mechanisms that cause an increase in RDW.More and more scholars believe that RDW can be used as an emerging inflammatory marker to reflect the inflammatory status of a disease and predict its prognosis.In recent years,some studies have shown that the RDW was higher in obese subjects than it in normal weight subjects,and it is an independent risk factor for the metabolic syndrome,but specific mechanisms are unclear.However,most of them have been conducted in adults,with insufficient child-based studies.In this study,we analyzed the changes and relationship between RDW and inflammatory indicators in obese children,expecting to clarify whether RDW can be used as a simple and economical indicator to assess the inflammatory status of obese children.Methods:The subjects of this study are children aged 7 to 14 years who were hospitalized in the pediatric ward of the Second Hospital of Dalian Medical University between January 2017 and December 2020.According to the standards of “BMI cut-off points for screening overweight and obesity in Chinese children aged 2-18 years” formulated in the year of 2009,those whose BMI ≥ the 95 th percentile of the same age and gender are defined as obese children.Children diagnosed as simple obesity are enrolled in the obese group,totaling 75 cases,while healthy children of normal weight are selected into the control group,totaling 52 cases,according to age and gender matching.The differences between obesity-related indexes,erythrocyte parameters,inflammatory factors and biochemical indexes in the obese and control groups are compared,and then the correlation between the indexes is analyzed.Results:1.The BMI,serum FINS,HOMA-IR,ALT,AST,TG and UA of the children in the obese group are all higher than those in the control group,however,the HDL level was lower than the control group,with statistically significant differences between the two groups(P < 0.05).There are not statistical differences in FPG,TC and LDL of the two groups(P > 0.05).2.The CRP,IL-2R,IL-6 and TNF-α of the children in the obese group are all higher than those in the control group,with statistically significant differences between the two groups(P < 0.05).There are not statistical differences in IL-1β,IL-8and IL-10 of the two groups(P > 0.05).3.The RBC,HCT,RDW-CV and HGB levels of the children in the obese group are all higher than those in the control group,however,the MCV level is lower than the control group,with statistically significant differences between the two groups(P< 0.05).There are not statistical differences in MCH and MCHC of the two groups(P > 0.05).4.The BMI of the children in the obese group is positively correlated with FINS and HOMA-IR,respectively(P < 0.05);IL-6 is positively correlated with BMI and HOMA-IR,respectively(P < 0.05),and there is no correlation with FINS(P > 0.05);TNF-α is positively correlated with BMI,FINS,and HOMA-IR,respectively(P <0.05);CRP and IL-2R are not correlated with BMI,FINS or HOMA-IR,respectively(P > 0.05).There is no correlation between insulin resistance index,inflammatory factors(CRP,IL-2R,IL-6,TNF-α)and liver function(ALT,AST),blood lipids(TG,HDL)or kidney function(UA,Cys-C),respectively(P > 0.05).5.The RDW-CV of the children in the obese group is positively correlated with BMI,FINS,HOMA-IR,IL-6 and TNF-α,respectively(P < 0.05),and MCV is negatively correlated with BMI and TNF-α,respectively(P < 0.05).There is no correlation between the remaining red blood cell parameters RBC,HCT,HGB,MCH,MCHC and obesity-related indexes as well as inflammatory factors(P > 0.05).Conclusion:1.The red blood cell parameters RBC,HCT,RDW-CV and HGB are all increased,but MCV is decreased in children with simple obesity.RDW-CV can be used as an inflammatory marker to evaluate the inflammatory status of the obese children.2.Children with simple obesity are prone to hyperinsulinemia,insulin resistance,abnormal liver function and kidney function,as well as metabolic abnormalities of blood lipids.3.Children with simple obesity are suffered from chronic low-grade inflammation and the inflammation probably involves in the development of obesity as well as insulin resistance.