Mediating effects of metabolic related indicators on the association between childhood overweight/obesity and left ventricular hypertrophy / 中国学校卫生

ABSTRACT

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 1 400 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 non overweight/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±7.6 μU/mL), apolipoprotein B (ApoB) (0.7±0.2 g/L), lowdensity 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±91.4 μmol/L) compared to those who were non-overweight/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 high density lipoprotein cholesterol (HDL-C) were lower in overweight/obese children (1.5±0.3 mmol/L) than in non-overweight/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 non-overweight/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.