Choice of vascular access and patient outcomes among older hemodialysis patients

 描述(由申请人提供)：Allon博士对透析血管通路的研究兴趣由来已久，在过去15年中发表了100多篇同行评议的文章，并获得了几笔NIH关于这一主题的资金资助。他的短期目标是提高我们对动静脉瘘(AVF)和移植物(AVG)患者临床结果的了解。他的长期目标是开发新的方法来改善这些临床结果。大约80%的美国ESRD患者开始使用中心静脉导管(CVC)进行血液透析(HD)。一旦HD开始，患者就会被转介给外科医生，以建立永久的血管通路，要么是AVF，要么是AVG。目前的普遍指导方针强烈建议放置AVF，而不是AVG。然而，一些小型观察性研究表明，对于老年HD患者，AVG可能是比AVF更好的选择，因为AVF失败率较高，患者生存时间相对较短。一次引流失败会导致对CVC的长期依赖，并伴随并发症，直到另一条有效的血管引流被放置并适合HD。我们假设，在使用CVC开始HD的老年HD患者中，放置AVG而不是AVF将导致更短的CVC依赖、更少的CRB发作、更少的住院和更长的患者生存时间。我们建议进行一项回顾性队列研究，研究对象是年龄&>65岁的新ESRD患者，他们在开始透析后6个月内接受了后续的AVF或AVG治疗，这些患者都有CVC且没有二次血管通路(AVF或AVG)。我们将比较两组患者(AVF和AVG)的原发通路失败率、放置通路后CVC依赖的持续时间、CRB的频率、与感染相关的住院频率和所有原因住院的频率，以及总体患者存活率。这项观察性研究的结果将被用来(1)提供关于在HD开始后接受AVF和AVG的老年HD患者的临床结果的有价值的信息，以及(2)为在该研究人群中接受AVF和AVG的确定性随机临床试验设计和执行功率分析所必需的可靠信息。

 DESCRIPTION (provided by applicant): Dr. Allon has had a long-standing research interest in vascular access for dialysis, culminating in over 100 peer-reviewed publications during the past 15 years, as well as several funded NIH grants on this topic. His short-term goal is to improve our understanding of the clinical outcomes of patients receiving arteriovenous fistulas (AVF) and grafts (AVG). His long-term goal is to develop novel approaches to improve these clinical outcomes. Approximately 80% of U.S. ESRD patients initiate hemodialysis (HD) with a central vein catheter (CVC). Once HD has been started the patient is referred to a surgeon for creation of a permanent vascular access, either an AVF or an AVG. The current consensus guidelines strongly recommend placing an AVF, rather than an AVG. However, several small observational studies have suggested that AVG may be a better choice than an AVF in elderly HD patients, due to the higher AVF failure rate and relatively short patient survival. Primary access failure leads to prolonged CVC-dependence, with its attendant complications, until another functioning vascular access is placed and suitable for HD. We hypothesize that in older HD patients who initiate HD with a CVC, placement of an AVG rather than an AVF will result in shorter CVC-dependence, fewer episodes of CRB, fewer hospitalizations and longer patient survival. We propose a retrospective cohort study focused on new ESRD patients age >65 years who initiate HD with a CVC and no secondary vascular access (AVF or AVG), and who receive a subsequent AVF or AVG within 6 months of initiating HD. We will compare the 2 patient cohorts (AVF vs. AVG) in terms of primary access failure rate, duration of CVC-dependence after access placement, frequency of CRB, frequency of infection-related hospitalization and all cause hospitalization, and overall patient survival. The results of this observational study will b used to (1) provide valuable information about clinical outcomes in elderly HD patients receiving an AVF vs. an AVG after initiation of HD, and (2) provide robust information necessary to design and perform a power analysis for a definitive randomized clinical trial of AVF vs AVG in this study population.