Objective: The study is to explore the association between trunk fat index (TFI) and carotid intima-media thickness (cIMT) among children aged 6-8 years old in Shunyi District, Beijing. Methods: The participants were enrolled from the child cohort on sensitization, puberty, obesity and cardiovascular risk (PROC) conducted in Shunyi District, Beijing from October 2018 to June 2019. The PROC used a community-based census-like design, and all eligible first-grade children from six public non-boarding primary schools in urban area were approached. Finally, a total of 1 503 children with written informed consent from parents and had complete data of TFI and cIMT were included for the present study. Sequential baseline surveys including anthropometric measurements, laboratory testing and ultrasonography measurement were conducted to collect the data on height, weight, body composition, blood pressure, serum lipids and cIMT. Linear regression was used to determine the predictors of cIMT, receiver operating characteristic (ROC) curve analysis was used to determine the cut-off value of TFI to identify children with high cIMT, and analysis of covariance was used to evaluate the post-consistency classification of cIMT by TFI. Results: The age of 1 503 participants was (6.7±0.3) years, and 752 boys accounted for 50.0%. The average cIMT was (0.358±0.024) and (0.355±0.023) mm, and the M (P25, P75) of TFI was 0.70 (0.22, 1.78) and 0.74 (0.23, 1.52) kg/m2 for boys and girls, respectively. The detection rates for boys and girls of high cIMT were 2.1% and 3.3%, respectively. Linear regression analysis showed that height, systolic blood pressure (SBP), diastolic blood pressure (DBP), TFI were positively correlated with cIMT in boys (P values<0.05). And height, SBP, triglyceride (TG), TFI were positively correlated with cIMT, and high-density lipoprotein cholesterol (HDL-C) was negatively correlated with cIMT in girls (P values<0.05). ROC curve analysis indicated that the best cut-off values for TFI to identify children with high cIMT were 1.78 and 1.14 kg/m2, at P75 and P66 for boys and girls, respectively. After grouped with the cut-off value of TFI and adjusted for age, height, SBP, DBP, TG, HDL-C, multivariable covariance analysis showed a consistent cut-off of inter-group cIMT mean by TFI groups (P values<0.005). Conclusion: TFI is associated with cIMT, which underscore its application potential in identifying early vascular structural damage.
目的： 探索北京市顺义区6~8岁儿童躯干脂肪指数（TFI）与颈动脉内中膜厚度（cIMT）的关系。 方法： 研究对象来自2018年10月至2019年6月在北京市顺义区开展的“儿童生长与健康队列”。采用人群普查的方法，最终纳入资料完整的1 503名6~8岁儿童为研究对象。通过体格检查、实验室检测和超声检查收集身高、体重、体成分、血压、血常规与生化和cIMT等信息，采用线性回归分析cIMT相关的因素，采用受试者工作特征（ROC）曲线分析确定TFI识别高cIMT儿童的最佳截断值，并同时采用协方差分析比较不同TFI儿童的cIMT水平的差异。 结果： 研究对象年龄为（6.7±0.3）岁，其中男童占50.0%（752名）。男、女童cIMT分别为（0.358±0.024）和（0.355±0.023）mm，TFI的M（P25，P75）分别为0.70（0.22， 1.78）和0.74（0.23， 1.52）kg/m2。男、女童高cIMT检出率分别为2.1%（16名）和3.3%（25名）。线性回归分析结果显示，男童身高、收缩压（SBP）、舒张压（DBP）、TFI与cIMT呈正相关（P值均<0.05）；女童身高、SBP、甘油三酯（TG）、TFI与cIMT呈正相关，高密度脂蛋白胆固醇（HDL-C）与cIMT呈负相关（P值均<0.05）。ROC曲线分析结果显示，TFI识别高cIMT的最佳截断值男童和女童为1.78和1.14 kg/m2，分别位于P75和P66。应用TFI最佳截断值进行分组，协方差分析结果表明，调整年龄、身高、SBP、DBP、TG和HDL-C等因素后，不同TFI男、女童的cIMT差异有统计学意义（P值均<0.005）。 结论： TFI与cIMT有关联，具有识别早期血管结构损害的潜在应用价值。.
Keywords: Carotid intima-media thickness; Child; Cohort study; Obesity, abdominal; Trunk fat index.