Reducing geographic disparities in kidney and liver allocation

减少肾脏和肝脏分配的地理差异

• 批准号: 9197041
• 负责人: DORRY L. SEGEV
• 金额: $ 63万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2020-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9197041
• 关键词: Accounting; Address; Area; Caring; Code; Congresses; Country; County; Event; Face; Goals; Heterogeneity; Incidence; Kidney; Kidney Transplantation; Laws; Liver; Liver diseases; Maps; Measures; Medical; Methodology; Modeling; Organ; Organ Donor; Organ Procurements; Organ Transplantation; Patients; Performance; Policies; Probability; Research; Risk; Services; Source; Staging; System; Techniques; Testing; Time; Transplantation; Uncertainty; Variant; Waiting Lists; Work; clinical decision-making; clinical practice; design; geographic difference; improved; innovation; liver transplantation; model design; mortality; novel strategies; organ allocation; organ procurement transplantation network; public health relevance; residence

Summary Congress dictated in 1998 that "neither place of residence nor place of listing should be a major determinant of access to a transplant," but geographic disparities in access to kidney and liver transplantation are a major problem that has persistently worsened. Kidneys are allocated by waiting time, but there are 8-fold differences in median waiting times across donation service areas (DSAs). Livers are intended to go to the candidate with the highest MELD (model of end-stage liver disease) score, but instead median MELD varies by 10 points across DSAs, and 90-day probability of LT for candidates with high MELD varies from 18%-86%. The Organ Procurement and Transplantation Network (OPTN) unanimously resolved in 2012 that "the existing geographic disparity in allocation… is unacceptably high," calling for studies of optimized systems. A few ad hoc fixes have been proposed, but optimizing policy has rarely been explored, and no comprehensive solution has ever been implemented. Even the two recent major policy changes, Share-35 and the new kidney allocation system (KAS), did not explicitly address geographic disparities. Clamorous scientific controversy over whether the geographic disparity in organ availability is truly structural or merely reflects heterogeneity in clinical practice and organ procurement organization performance contributes to the policy stalemate. We have started working closely with the OPTN Liver Committee to design optimized sharing districts that would significantly reduce geographic variation in access to deceased donor livers. However, this preliminary work is currently limited by poor metrics of geographic variation and uncorrected measures of supply and demand. Furthermore, other promising concepts, like redrawing DSA boundaries, or dynamic prioritization of candidates without pre-determined maps, have not yet been explored or evaluated. Finally, no work has been done to adapt optimization models designed for liver allocation to the different priorities of kidney allocation. We will develop new approaches to making transplantation more equitable, considering both clinical practice and allocation systems. Using an innovative adaptation of mathematical optimization and statistical inference to transplant policy, we will isolate the fundamental drivers of geographic disparity and outline promising policies to make deceased donor organs equally available to candidates across the country. We will address the following aims: (1) To construct metrics of geographic variation in access to liver and kidney transplantation that adjust for heterogeneity inherent to clinical practice; (2) To measure fundamental demand for and supply of organs; (3) To understand the impact of recent allocation changes on clinical decision-making and geographic disparities; and (4) To design and test optimized sharing systems that reduce geographic disparity while explicitly accounting for uncertainty in supply and demand. The proposed research directly addresses a Congressional mandate and uses the approach favored by the OPTN. More equitable organ distribution will save lives and improve the care of over 100,000 patients currently at risk of dying on the waiting list.

概括 国会于1998年决定“居住地或上市地点应该是主要的确定者 进入移植，“但是进入肾脏和肝移植的地理差异是主要的 持续忘记的问题。肾脏是通过等待时间分配的，但是有8倍的差异 在捐赠服务领域（DSA）的中位等待时间中。肝脏打算与 最高的融合（终末期肝病模型）得分，而中值融合了10分 跨DSA，LT的LT概率为90天，高融合品品种从18％-86％开始。 器官采购和移植网络（OPTN）在2012年一致解决了“ 分配中现有的地理差异……令人难以置信的高度”，呼吁研究优化的系统。 很少有人提出临时修复，但是很少探索优化政策，也没有全面 解决方案曾经实施过。即使是最近的两个重大政策变化，股-35和新肾脏 分配系统（KAS）未明确解决地理分布。喧闹的科学争议 关于有机可用性的地理差异是真正结构性的还是仅反映了异质性 临床实践和器官采购组织的绩效有助于政策僵局。 我们已经开始与Optn肝委员会紧密合作，以设计优化的共享区， 将大大减少进入已故捐助者生活的地理差异。但是，这个初步 目前，工作受地理差异和未校正的供应措施的限制和 要求。此外，其他有希望的概念，例如重绘DSA边界或动态优先级 没有预定地图的候选人尚未探索或评估。最后，没有工作 这样做是为了调整旨在肝脏分配的优化模型，以符合肾脏分配的不同优先级。 考虑到这两种临床实践，我们将开发新方法使移植更加公平 和分配系统。使用数学优化和统计推断的创新改编 为了移植政策，我们将隔离地理差异的基本驱动力和概述有希望的 使全国各地候选人同样可用的已故捐赠者器官的政策。我们将解决 以下目的：（1）构建进入肝脏和肾脏移植的地理变化的指标 调整了异质性继承的临床实践； （2）衡量对和供应的基本需求 器官（3）了解最近分配变化对临床决策和 地理差异； （4）设计和测试优化的共享系统，以减少地理差异 同时明确考虑供求的不确定性。拟议的研究直接解决了 国会任务并使用OPTN偏爱的方法。更公平的器官分布将 挽救生命并改善目前有死于候补名单的100,000多名患者的护理。