代谢相关指标在儿童超重肥胖与左心室肥厚关联间的中介作用

Mediating effects of metabolicrelated indicators on the association between childhood overweight/obesity and left ventricular hypertrophy

目的探讨血压、血糖、血脂和血清尿酸在儿童超重肥胖与左心室肥厚(LVH)间的中介作用,为心血管疾病儿童早期防控提供科学依据。方法采用方便整群抽样方法,于2017年11月至2018年1月在山东省淄博市桓台县1所公立学校选取1400名6~11岁儿童开展基线调查。根据体质量指数(BMI)分类标准,将研究对象分为非超重肥胖组(787名)和超重肥胖组(613名)。采用R软件的mediation包分析代谢相关指标在儿童超重肥胖与LVH关联间的中介作用。结果超重肥胖组儿童的BMI-Z评分(2.0±0.8)、收缩压(SBP)(109.1±8.9)mmHg、舒张压(DBP)(65.4±6.8)mmHg、空腹血糖(FPG)(4.8±0.5)mmol/L、胰岛素(INS)(11.3±7.6)μU/mL、载脂蛋白B(ApoB)(0.7±0.2)g/L、低密度脂蛋白胆固醇(LDL-C)(2.4±0.7)mmol/L、总胆固醇(TC)(4.2±0.9)mmol/L、甘油三酯(TG)(0.9±0.4)mmol/L、血清尿酸(SUA)(321.2±91.4)μmol/L水平均高于非超重肥胖组[(-0.2±0.7)、(104.3±8.8)mmHg、(62.2±6.2)mmHg、(4.7±0.6)mmol/L、(6.1±4.2)μU/mL、(0.6±0.2)g/L、(2.2±0.6)mmol/L、(4.1±0.7)mmol/L、(0.7±0.2)mmol/L、(278.6±74.7)μmol/L],超重肥胖组儿童的高密度脂蛋白胆固醇(HDL-C)水平(1.5±0.3)mmol/L低于非超重肥胖组(1.7±0.4)mmol/L,差异均有统计学意义(t值分别为53.66,9.88,9.19,3.60,16.32,7.36,5.11,2.55,11.08,9.58,-10.31,P值均<0.05)。调整性别、年龄、睡眠时间、运动时间、视屏时间、蔬果和碳酸饮料摄入量等潜在混杂因素后,超重肥胖儿童发生LVH的风险是非超重肥胖儿童的8.72倍(OR=8.72,95%CI=5.45~14.66,P<0.01)。中介分析显示,INS、HDL-C、LDL-C、TG、ApoB、SUA部分介导了儿童超重肥胖与LVH之间的关联,其中INS和TG中介效应相对较大,占比分别为28.05%和13.71%。结论INS、HDL-C、LDL-C、TG、ApoB和SUA是儿童超重肥胖与LVH关联间的中间危险因素。控制儿童期代谢指标处于健康水平可能有利于减轻超重肥胖儿童的心血管疾病负担。

Objective To examine the mediating effects of blood pressure,glucose,lipids,and serum uric acid on the association between childhood overweight/obesity and left ventricular hypertrophy(LVH),and to provide scientific evidence for the prevention and control of cardiovascular diseases during childhood.Methods One public school in Huantai County,Zibo City was selected to conduct the baseline survey from November 2017 to January 2018 using a convenient cluster sampling method.A total of 1400 children aged 6 to 11 were included in the study.According to the classification criteria based on body mass index(BMI),participants were divided into the nonoverweight/obese group(n=787)and the overweight/obese group(n=613).The mediating effects of metabolic variables on the association between childhood overweight/obesity and left ventricular hypertrophy(LVH)were analyzed using the"mediation"package in R software.Results Children who were overweight/obese had higher levels of BMI-Z score(2.0±0.8),systolic blood pressure(SBP)(109.1±8.9 mmHg),diastolic blood pressure(DBP)(65.4±6.8 mmHg),fasting plasma glucose(FPG)(4.8±0.5 mmol/L),insulin(INS)(11.3±7.6μU/mL),apolipoprotein B(ApoB)(0.7±0.2 g/L),lowdensity lipoprotein cholesterol(LDL-C)(2.4±0.7 mmol/L),total cholesterol(TC)(4.2±0.9 mmol/L),triglycerides(TG)(0.9±0.4 mmol/L),and serum uric acid(SUA)(321.2±91.4μmol/L)compared to those who were nonoverweight/obese[the corresponding values were(-0.2±0.7),(104.3±8.8)mmHg,(62.2±6.2)mmHg,(4.7±0.6)mmol/L,(6.1±4.2)μU/mL,(0.6±0.2)g/L,(2.2±0.6)mmol/L,(4.1±0.7)mmol/L,(0.7±0.2)mmol/L,and(278.6±74.7)μmol/L,respectively],whereas the levels of highdensity lipoprotein cholesterol(HDL-C)were lower in overweight/obese children(1.5±0.3 mmol/L)than in nonoverweight/obese children(1.7±0.4 mmol/L).All differences were statistically significant(t=53.66,9.88,9.19,3.60,16.32,7.36,5.11,2.55,11.08,9.58,-10.31,P<0.05).After adjusting for potential covariates,overweight/obese children had 8.72 times increased risk of developing LVH compared to the nonoverweight/obese children(OR=8.72,95%CI=5.45-14.66,P<0.01).Mediation analysis showed that INS,HDL-C,LDL-C,TG,ApoB,and SUA partially mediated the association between childhood overweight/obesity and LVH,and among these,INS and TG had relatively strong mediating effects,accounting for 28.05%and 13.71%of the total effects,respectively.Conclusions INS,HDL-C,LDL-C,TG,ApoB,and SUA are intermediate risk factors on the association between childhood overweight/obesity and LVH.Keeping metabolic indicators(especially INS and TG)at healthy levels is particularly important for reducing the burden of cardiovascular diseases in overweight/obese children.