Karjoo Sara
Department of Pediatrics, Johns Hopkins Medicine, All Children's Hospital, St. Petersburg, FL, United States.
Front Pediatr. 2018 Nov 16;6:345. doi: 10.3389/fped.2018.00345. eCollection 2018.
Carotid intima media thickness (cIMT) and brachial flow-mediated dilation (FMD) evaluated by ultrasound are non-invasive markers of atherosclerosis. Increased cIMT in adults has been correlated to early vascular damage. Several studies show similar correlations of elevated cIMT in children with obesity, hyperlipidemia, and metabolic syndrome. Additionally, several articles have correlated non-alcoholic fatty liver disease (NAFLD) with elevated cIMT, indicating early atherosclerosis. It is alarming that these vascular changes may be seen in children as young as 10 years of age. Children with NAFLD may also have an increased pulse wave velocity that correlates to increased arterial stiffness and increased left ventricular dimension, mass, and diastolic dysfunction. These articles are persuasive, indicating a correlation of Pediatric NAFLD and early vascular disease. However, study limitations include the use of elevated alanine aminotransferase (ALT) and echogenic changes on ultrasound that may have low accuracy to identify NAFLD. Ultrasound has low sensitivities and specificities for detection of NAFLD and therefore is not recommended for diagnosis. In comparison, studies that used liver biopsy or proton magnetic resonance spectroscopy to identify NAFLD did not find a correlation with elevated cIMT or reduction in FMD. Due to these conflicting findings, more studies looking at cIMT and FMD changes in children with NAFLD are needed with more accurate diagnostic methods for steatosis to identify if there truly is a correlation of increased liver steatosis to early atherosclerosis.
通过超声评估的颈动脉内膜中层厚度(cIMT)和肱动脉血流介导的血管舒张功能(FMD)是动脉粥样硬化的非侵入性标志物。成人cIMT增加与早期血管损伤相关。多项研究表明,肥胖、高脂血症和代谢综合征儿童的cIMT升高也存在类似的相关性。此外,多篇文章将非酒精性脂肪性肝病(NAFLD)与cIMT升高相关联,提示早期动脉粥样硬化。令人担忧的是,这些血管变化在年仅10岁的儿童中就可能出现。患有NAFLD的儿童脉搏波速度也可能增加,这与动脉僵硬度增加、左心室尺寸、质量增加以及舒张功能障碍相关。这些文章很有说服力,表明儿童NAFLD与早期血管疾病之间存在关联。然而,研究的局限性包括使用丙氨酸转氨酶(ALT)升高以及超声回声改变来识别NAFLD,其准确性可能较低。超声检测NAFLD的敏感性和特异性较低,因此不推荐用于诊断。相比之下,使用肝活检或质子磁共振波谱来识别NAFLD的研究未发现与cIMT升高或FMD降低相关。由于这些相互矛盾的结果,需要更多采用更准确的脂肪变性诊断方法的研究,来观察NAFLD儿童的cIMT和FMD变化,以确定肝脏脂肪变性增加与早期动脉粥样硬化之间是否真的存在关联。