Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD.
Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, MD.
Transplantation. 2019 Oct;103(10):2113-2120. doi: 10.1097/TP.0000000000002643.
The Organ Procurement and Transplantation Network implemented Share 35 on June 18, 2013, to broaden deceased donor liver sharing within regional boundaries. We investigated whether increased sharing under Share 35 impacted geographic disparity in deceased donor liver transplantation (DDLT) across donation service areas (DSAs).
Using Scientific Registry of Transplant Recipients June 2009 to June 2017, we identified 86 083 adult liver transplant candidates and retrospectively estimated Model for End-Stage Liver Disease (MELD)-adjusted DDLT rates using nested multilevel Poisson regression with random intercepts for DSA and transplant program. From the variance in DDLT rates across 49 DSAs and 102 programs, we derived the DSA-level median incidence rate ratio (MIRR) of DDLT rates. MIRR is a robust metric of heterogeneity across each hierarchical level; larger MIRR indicates greater disparity.
MIRR was 2.18 pre-Share 35 and 2.16 post-Share 35. Thus, 2 candidates with the same MELD in 2 different DSAs were expected to have a 2.2-fold difference in DDLT rate driven by geography alone. After accounting for program-level heterogeneity, MIRR was attenuated to 2.10 pre-Share 35 and 1.96 post-Share 35. For candidates with MELD 15-34, MIRR decreased from 2.51 pre- to 2.27 post-Share 35, and for candidates with MELD 35-40, MIRR increased from 1.46 pre- to 1.51 post-Share 35, independent of program-level heterogeneity in DDLT. DSA-level heterogeneity in DDLT rates was greater than program-level heterogeneity pre- and post-Share 35.
Geographic disparity substantially impacted DDLT rates before and after Share 35, independent of program-level heterogeneity and particularly for candidates with MELD 35-40. Despite broader sharing, geography remains a major determinant of access to DDLT.
器官获取与移植网络于 2013 年 6 月 18 日实施了 Share 35，以扩大区域内的已故供肝共享。我们调查了 Share 35 实施后，在捐赠服务区域（DSA）内是否会影响已故供肝移植（DDLT）的地域差异。
使用 2009 年 6 月至 2017 年 6 月的移植受者科学注册处的数据，我们确定了 86083 名成人肝移植候选者，并使用嵌套多层泊松回归模型，使用 DSA 和移植计划的随机截距对终末期肝病模型（MELD）调整后的 DDLT 率进行了回顾性估计。根据 49 个 DSA 和 102 个项目中 DDLT 率的方差，我们得出了 DSA 水平的中位数发病率比（MIRR）。MIRR 是每个层次异质性的稳健指标；更大的 MIRR 表示更大的差异。
Share 35 实施前的 MIRR 为 2.18，实施后的 MIRR 为 2.16。因此，2 名 MELD 相同的候选者在 2 个不同的 DSA 中，预计仅由于地理位置就会导致 DDLT 率相差 2.2 倍。在考虑到项目水平的异质性后，MIRR 从 Share 35 实施前的 2.10 减弱至实施后的 1.96。对于 MELD 为 15-34 的候选者，MIRR 从 Share 35 实施前的 2.51 降至实施后的 2.27，对于 MELD 为 35-40 的候选者，MIRR 从 Share 35 实施前的 1.46 增至实施后的 1.51，而与 DDLT 的项目水平异质性无关。Share 35 实施前后，DSA 水平的 DDLT 率异质性大于项目水平的异质性。
地理差异在 Share 35 实施前后极大地影响了 DDLT 率，独立于项目水平的异质性，特别是对 MELD 为 35-40 的候选者。尽管共享范围更广，但地理因素仍然是获得 DDLT 的主要决定因素。
