Department of Nephrology, Children's National Health System, Washington, DC, USA.
Department of Cardiology, Children's National Health System, Washington, DC, USA.
Pediatr Nephrol. 2018 Aug;33(8):1419-1428. doi: 10.1007/s00467-017-3860-8. Epub 2017 Dec 30.
Obesity and metabolic syndrome (MS) are common after kidney transplantation, but their contribution to adverse cardiovascular (CV) outcomes in children are not well known. A prospective, controlled, longitudinal cohort study was conducted to investigate the effects of obesity and MS on left ventricular hypertrophy (LVH) and myocardial strain in pediatric kidney transplant recipients.
Transplant recipients (n = 42) had anthropometrics [body mass index (BMI), waist circumference, waist-to-height ratio], biochemical parameters (fasting glucose, lipid panel, HbA1c%), and echocardiogram with speckle tracking analysis for strain measured at 1, 18, and 30 months post-transplant. Additionally, 35 pre-transplant echocardiograms were analyzed retrospectively. Healthy children (n = 24) served as controls.
Waist-to-height ratio detected abdominal obesity in 46% of transplant patients, whereas only 8.1% were identified as obese by waist circumference. Ejection fraction and fractional shortening of the transplant group were normal. Prevalence of LVH was 35.2%, 17.1%, and 35.5% at 1, 18, and 30 months respectively. The longitudinal strain of transplant group was worse than controls at all time points (p < 0.001). Hemodialysis was independently associated with 21% worse longitudinal strain during the pre-transplant period (p = 0.04). After transplantation, obesity, MS, and systolic hypertension predicted increased odds of LVH (p < 0.04). Worse longitudinal strain was independently associated with obesity, MS, hypertension, and the combination of MS with elevated low density lipoprotein (LDL) cholesterol (p < 0.04), whereas higher estimated glomerular filtration rate (eGFR) conferred a protective effect (p < 0.001).
Obesity and MS adversely affect CV outcomes after transplantation. Further studies are needed to investigate speckle tracking echocardiography as a tool for early detection of subclinical myocardial dysfunction in this population.
肥胖症和代谢综合征（MS）在肾移植后较为常见，但它们对儿童不良心血管（CV）结局的影响尚不清楚。本前瞻性、对照、纵向队列研究旨在调查肥胖症和 MS 对儿科肾移植受者左心室肥厚（LVH）和心肌应变的影响。
移植受者（n=42）进行了人体测量学（体重指数（BMI）、腰围、腰高比）、生化参数（空腹血糖、血脂谱、HbA1c%）以及超声心动图斑点追踪分析以测量移植后 1、18 和 30 个月的应变。此外，还回顾性分析了 35 例移植前的超声心动图。健康儿童（n=24）作为对照组。
腰围与身高比检测到 46%的移植患者存在腹部肥胖，而仅 8.1%的患者通过腰围被认定为肥胖。移植组的射血分数和短轴缩短率正常。LVH 的患病率分别为 1 个月时 35.2%、18 个月时 17.1%和 30 个月时 35.5%。移植组的纵向应变在所有时间点均差于对照组（p<0.001）。血液透析在移植前与纵向应变恶化 21%独立相关（p=0.04）。移植后，肥胖症、MS 和收缩期高血压预测 LVH 的发生几率增加（p<0.04）。更差的纵向应变与肥胖症、MS、高血压以及 MS 与升高的低密度脂蛋白（LDL）胆固醇的组合独立相关（p<0.04），而更高的估算肾小球滤过率（eGFR）则具有保护作用（p<0.001）。
肥胖症和 MS 对移植后的 CV 结局有不利影响。需要进一步研究斑点追踪超声心动图作为检测该人群亚临床心肌功能障碍的早期工具。
