Associations Of Elevated Body Fat Content With Elevated Blood Pressure,Dyslipidemia,Elevated Blood Glucose And Metabolic Syndrome In Children

BackgroundCardiovascular disease(CVD)is an important public health issue in China.Researches showed that CVD can be traced back to childhood.Therefore,it is of great public health significance to pay attention to the identification and prevention for CVD from childhood.Recently,the prevalence of elevated blood pressure,dyslipidemia,elevated blood glucose,and metabolic syndrome among children have increased year by year,which seriously affects the children’s physical and mental health,and may have long-term effects on the cardiovascular health in adulthood.Active prevention and treatment for these risk factors in childhood are crucial for preventing CVD in adulthood.If not actively controlled,the disease and economic burden in adulthood will increase.Overweight/obesity is one of the most important risk factors for elevated blood pressure,dyslipidemia,elevated blood glucose,and metabolic syndrome.At the same time,the prevalence of overweight/obesity in children has increased annually over the last few years.Most previous studies have mainly used the body mass index(BMI)as a standard for children with systemic(general)overweight and obesity.However,BMI cannot distinguish between fat and non-fat tissue,and there is a possibility to misclassify overweight/obese with other people.Compared to BMI,body fat content can more directly reflect the amount and distribution of fat tissue in the body,and can identify cardiovascular-related metabolic abnormalities that BMI cannot explain.Therefore,body fat content plays an important role in the identification of C VD risk factors in childhood.Currently,there are few studies on the relationship between body fat content and cardiovascular metabolic indicators among children in China.Therefore,we aimed to explore the relationships of children’s elevated body fat content with elevated blood pressure,dyslipidemia,elevated blood glucose,and metabolic syndrome based on the latest follow-up data from the "Huantai Childhood Cardiovascular Health Cohort Study" and to provide scientific basis for the early prevention and control of C VD in lifespan.Objectives1.To examine the relationship between elevated body fat content and elevated blood pressure,dyslipidemia,elevated blood glucose and metabolic syndrome in children.2.To examine the dose-response relationship between elevated body fat content and elevated blood pressure,dyslipidemia,elevated blood glucose and metabolic syndrome in children.MethodsThe subjects were selected from "Huantai Childhood Cardiovascular Health Cohort Study",an on-going cohort study with biennial follow-up,which collected subjects from grades 1 to 5 in a primary school in Huantai County using convenient cluster sampling.Data on 1,346 children aged 10 to 15 years were extracted from the latest follow-up which has been conducted from October 2021 to January 2022.Excluding those with missing data,a total of 1,251 ones with complete data were included in this study.The indicators including body fat percentage,body fat mass(FM),and fat mass index(FMI),systolic blood pressure,diastolic blood pressure,triglycerides(TG),total cholesterol(TC),low density lipoprotein cholesterol(LDL-C),high density lipoprotein cholesterol(HDL-C),and fasting blood glucose were measured.Due to the lack of a unified body fat content standard in China,this study divided the body fat percentage,FM,and FMI into low and high levels based on P50.After adjusting for potential confounders such as age,gender,second-hand smoke exposure,sleep time,screen viewing time,physical activity,intake of vegetables and fruits,and intake of carbonated drinks,multivariate logistic regression models were used to analyze the relationships of body fat percentage,FM,and FMI with elevated blood pressure,dyslipidemia,elevated blood glucose,and metabolic syndrome,respectively.At the same time,stratified analysis by gender(boys and girls)and BMI(normal weight and overweight/obese)were performed.The dose-response relationships of elevated body fat percentage,FM,and FMI with elevated blood pressure,dyslipidemia,elevated blood glucose,and metabolic syndrome were analyzed using restricted cubic spline(RCS)mdels.Results1.Relationship between elevated body fat content and elevated blood pressureAfter adjusting for potential confounders,elevated body fat percentage and elevated FMI were associated with high systolic blood pressure(elevated body fat percentage:OR=5.04,95%CI:3.59-7.09;elevated FMI:OR=5.03,95%CI:3.59-7.07),high diastolic blood pressure(elevated body fat percentage:OR=2.89,95%CI:1.08-7.72;elevated FMI:OR=2.77,95%CI:1.05-7.26),and elevated blood pressure(elevated body fat percentage:OR=5.05,95%CI:3.61-7.08;elevated FMI:OR=5.02,95%CI:3.59-7.02),respectively.Elevated FM was associated with high systolic blood pressure(OR=5.93,95%CI:4.16-8.44)and high blood pressure(OR=5.86,95%CI:4.14-8.30),but not with high diastolic blood pressure.In the stratified analysis by gender and weight status,elevated body fat percentage,elevated FM,and elevated FMI were all associated with high systolic blood pressure and elevated blood pressure(all P<0.05),but not with high diastolic blood pressure(all P>0.05).Further,there was a significant linear dose-response relationship of body fat percentage,FM,and FNI with the risk of high systolic blood pressure,high diastolic blood pressure,and elevated blood pressure(all Pnon-linear>0.05).2.Relationship between elevated body fat content and dyslipidemiaAfter adjusting for potential confounders,elevated body fat percentage,elevated FM,and elevated FMI were associated with low HDL-C(elevated body fat percentage:OR=7.62,95%CI:4.08-14.23;elevated FM:OR=6.75,95%CI:3.62-12.57;elevated FMI:OR=6.76,95%CI:3.65-12.53),High LDL-C(elevated body fat percentage:OR=2.33,95%CI:1.37-3.96;elevated FM:OR=2.07,95%CI:1.22-3.49;elevated FMI:OR=1.98,95%CI:1.18-3.32),and high TG(elevated body fat percentage:OR=7.29,95%CI:3.75-14.17;elevated FM:OR=5.40,95%CI:2.94-9.94;elevated FMI:OR=6.14,95%CI:3.25-11.59),but not associated with TC(all P>0.05).The results among boys were consistent with that in the overall population.Among girls,elevated body fat percentage,elevated FM,and elevated FMI were not associated with LDL-C or TC(all P>0.05).In children with normal body weight,elevated body fat percentage and elevated FM were associated with high LDL-C(all P<0.05).However,elevated body fat percentage was associated with low HDL-C and high TG(all P<0.05)among overweight/obese children.Body fat percentage,FM,or FMI had a linear dose-response relationship with the risk of high LDL-C(all P non-linear>0.05).3.Relationship between elevated body fat composition and elevated blood glucoseAfter adjusting all covariates,there was no association of elevated body fat percentage,elevated FM and elevated FMI with elevated blood glucose(all P>0.05).Results in both sex and weight status subgroups were similar to those in overall subjects.In addition,there was no dose-response relationship of body fat percentage,FM,and FMI with the risk of elevated blood glucose.4.Relationship between elevated body fat content and metabolic syndromeAfter adjusting all covariates,elevated body fat percentage(OR=41.06,95%CI:14.84-113.62),elevated FM(OR=36.58,95%CI:13.22-101.21),and elevated FMI(OR=46.69,95%CI:14.63-149.02)were associated with metabolic syndrome.The results in boys were consistent with those in the overall,and no association between elevated body fat percentage and metabolic syndrome was found in girls.Elevated body fat percentage,elevated FM,and elevated FMI were not found to be associated with metabolic syndrome in normal-weight subjects(all P<0.05),but significant associations were found in overweight/obese ones(all P>0.05).At the same time,body fat percentage,FM or FMI had a nonlinear dose-response relationship with the risk of metabolic syndrome(all Pnon-linear<0.05).Conclusion1.Elevated body fat content had positive associations and dose-response relationships with high systolic blood pressure,high diastolic blood pressure,and elevated blood pressure in children.2.Elevated body fat content was positively associated with low HDL-C,high LDL-C,and high TG in children.There was a dose-response relationship between elevated body fat content and high LDL-C in children.3.There is no significant association or dose-response relationship between elevated body fat content and elevated blood sugar in children.4.There were positive associations and dose-response relationship between elevated body fat content and metabolic syndrome in children.