Intradialytic Protein Supplementation and Exercise Training in Dialysis Patients

描述（由申请人提供）： 接受血液透析治疗的慢性肾病（CKD）患者（CKD 5期）患有多种可能与机制相关的共病。蛋白质营养不良、肌肉萎缩和消瘦尤其常见，这些导致肌肉力量下降、身体功能下降和身体活动水平低下。缺乏身体活动会加剧这些功能下降，并促进心血管疾病（CVD）和骨骼疾病。这种疾病和残疾的循环大大降低了透析患者的生活质量（QOL）并增加了死亡率。透析中蛋白质补充和耐力运动训练是成本相对较低的疗法，有可能降低这些合并症的患病率或严重程度，但很少有研究直接评估其疗效。拟定研究的目的是评价透析中口服蛋白质补充剂（伴或不伴透析中运动训练（骑自行车））对身体功能、QOL、CVD和骨骼健康相关指标的影响。为了解决这些问题，血液透析患者将被随机分配至以下组，持续12个月：1）常规护理/对照组（CON）; 2）透析中蛋白质补充组（PRO）;或3）透析中蛋白质补充+运动训练组（PRO+EX）。将通过各种客观和主观任务评估身体功能、肌肉力量和QOL，DXA将用于测量瘦体重、骨密度和腹主动脉钙化，血管超声将用于测量动脉硬度和颈动脉内膜中层厚度，超声心动图将用于评估心脏结构和功能。此外，将通过标准生物化学测定法测量影响CVD风险和肌肉和骨骼骨骼抗衰老的炎症介质、矿物质调节蛋白和生长因子的循环水平，以评估蛋白质补充和运动训练可能影响这些共病状况的潜在机制。我们假设PRO+EX组和PRO组的身体功能、功能性CVD结局和危险因素、骨密度和QOL指数将发生有益的变化，而CON组则没有。此外，PRO+EX组的这些变化幅度最大，除了与骨密度相关的变量。

DESCRIPTION (provided by applicant): Chronic kidney disease (CKD) patients receiving hemodialysis treatment (CKD stage 5) suffer from a variety of co-morbid diseases that may be mechanistically related. Protein malnutrition, muscle catabolism and wasting are especially common, and these lead to reduced muscle strength, declines in physical function, and low levels of physical activity. Physical inactivity exacerbates these functional declines, and also promotes cardiovascular disease (CVD) and bone disorders. This cycle of disease and disability greatly reduces the quality of life (QOL) and increases mortality rates in dialysis patients. Intradialytic protein supplementation and endurance exercise training are relatively low-cost therapies that have the potential to reduce the prevalence or severity of these co-morbid conditions, but few studies have directly assessed their efficacy. The objective of the proposed research is to evaluate the effects of intradialytic oral protein supplementation, with and without concomitant intradialytic exercise training (cycling), on measures related to physical function, QOL, CVD, and bone health. To address these questions, hemodialysis patients will be randomized to the following groups for 12 months: 1) usual care/control (CON); 2) intradialytic protein supplementation (PRO); or 3) intradialytic protein supplementation + exercise training (PRO+EX). Physical function, muscle strength, and QOL will be assessed by a variety of objective and subjective tasks, DXA will be used to measure lean mass, bone density, and abdominal aortic calcification, vascular ultrasound will be used to measure arterial stiffness and carotid intima-media thickness, and echocardiography will be used to assess cardiac structure and function. In addition, circulating levels of inflammatory mediators, mineral regulatory proteins, and growth factors that impact CVD risk and muscle and bone anabolism will be measured by standard biochemical assays to assess potential mechanisms by which protein supplementation and exercise training may influence these co-morbid conditions. We hypothesize that beneficial changes in physical function, functional CVD outcomes and risk factors, bone density, and QOL indices will occur in PRO+EX and PRO, but not in CON. Furthermore, the magnitude of these changes will be greatest in PRO+EX for all variables except those related to bone density.