Division of Nephrology and Dialysis, St. Anna University Hospital, 44121 Ferrara, Italy.
Division of Nephrology, ASST Sette Laghi, 21100 Varese, Italy.
Nutrients. 2020 May 12;12(5):1388. doi: 10.3390/nu12051388.
Protein Energy Wasting (PEW) in hemodialysis (HD) patients is a multifactorial condition due to specific pathology-related pathogenetic mechanisms, leading to loss of skeletal muscle mass in HD patients. Computed Tomography and Magnetic Resonance Imaging still represent the gold standard techniques for body composition assessment. However, their widespread application in clinical practice is difficult and body composition evaluation in HD patients is mainly based on conventional anthropometric nutritional indexes and bioelectrical impedance vector analysis (BIVA). Little data is currently available on ultrasound (US)-based measurements of muscle mass and fat tissue in this clinical setting. The purpose of our study is to ascertain: (1) if there are differences between quadriceps rectus femoris muscle (QRFM) thickness and abdominal/thigh subcutaneous fat tissue (SFT) measured by US between HD patients and healthy subjects; (2) if there is any correlation between QRFM and abdominal/thigh SFT thickness by US, and BIVA/conventional nutritional indexes in HD patients. We enrolled 65 consecutive HD patients and 33 healthy subjects. Demographic and laboratory were collected. The malnutrition inflammation score (MIS) was calculated. Using B-mode US system, the QRFM and SFT thicknesses were measured at the level of three landmarks in both thighs (superior anterior iliac spine, upper pole of the patella, the midpoint of the tract included between the previous points). SFT was also measured at the level of the periumbilical point. The mono frequency (50 KHz) BIVA was conducted using bioelectrical measurements (Rz, resistance; Xc, reactance; adjusted for height, Rz/H and Xc/H; PA, phase angle). 58.5% were men and the mean age was 69 (SD 13.7) years. QRFM and thigh SFT thicknesses were reduced in HD patients as compared to healthy subjects ( < 0.01). Similarly, also BIVA parameters, expression of lean body mass, were lower ( < 0.001), except for Rz and Rz/H in HD patients. The average QRFM thickness of both thighs at top, mid, lower landmarks were positively correlated with PA and body cell mass (BCM) by BIVA, while negatively correlated with Rz/H ( < 0.05). Abdominal SFT was positively correlated with PA, BCM and basal metabolic rate (BMR) ( < 0.05). Our study shows that ultrasound QRFM and thigh SFT thicknesses were reduced in HD patients and that muscle ultrasound measurements were significantly correlated with BIVA parameters.
蛋白质能量消耗（PEW）在血液透析（HD）患者中是一种多因素的病症，源于特定的与病理学相关的发病机制，导致 HD 患者骨骼肌质量的损失。计算机断层扫描和磁共振成像仍然是身体成分评估的金标准技术。然而，它们在临床实践中的广泛应用是困难的，HD 患者的身体成分评估主要基于传统的人体测量营养指数和生物电阻抗向量分析（BIVA）。目前在这种临床环境下，关于肌肉质量和脂肪组织的超声（US）测量数据很少。我们研究的目的是确定：（1）HD 患者和健康受试者之间通过 US 测量的股直肌（QRFM）厚度和腹部/大腿皮下脂肪组织（SFT）是否存在差异；（2）HD 患者的 QRFM 与 US 测量的腹部/大腿 SFT 厚度之间，以及与 BIVA/传统营养指数之间是否存在任何相关性。我们招募了 65 名连续的 HD 患者和 33 名健康受试者。收集了人口统计学和实验室数据。计算了营养不良炎症评分（MIS）。使用 B 型超声系统，在大腿的三个标志水平（髂前上棘、髌骨上极、前两点之间的轨迹中点）测量 QRFM 和 SFT 厚度。SFT 也在脐周水平测量。使用生物电阻抗测量（Rz，电阻；Xc，电抗；校正高度后，Rz/H 和 Xc/H；PA，相位角）进行单频（50 KHz）BIVA。58.5%为男性，平均年龄为 69（SD 13.7）岁。与健康受试者相比，HD 患者的 QRFM 和大腿 SFT 厚度均减少（<0.01）。同样，BIVA 表达的瘦体质量等参数也较低（<0.001），除了 HD 患者的 Rz 和 Rz/H。大腿上部、中部和下部标志的 QRFM 平均厚度与 BIVA 的 PA 和细胞内液质量（BCM）呈正相关，而与 Rz/H 呈负相关（<0.05）。腹部 SFT 与 PA、BCM 和基础代谢率（BMR）呈正相关（<0.05）。我们的研究表明，HD 患者的超声 QRFM 和大腿 SFT 厚度减少，肌肉超声测量与 BIVA 参数显著相关。
