Background

In 2018, United Network for Organ Sharing (UNOS) extended the radius for which a heart transplant candidate can match with a donor, and outcomes across population densities are unknown. We sought to determine whether the policy change was associated with differences in heart transplant waitlist time or death post-transplant for patients from rural, micropolitan, and metropolitan settings.

Methods

Using the Scientific Registry of Transplant Recipients, we evaluated U.S. adult patients listed for heart transplant from Janurary 2017 to September 2019 with follow-up through March 2020. Patients were stratified by home zip-codes to either metropolitan, micropolitan, or rural settings. Fine and Gray and Cox models were respectively used to estimate Sub-distribution hazard ratios (SHR) of heart transplant with death or removal from transplant list as a competing event, and HR of death post-transplant within population densities after versus before the UNOS policy change date, October 18, 2018. Analyses were adjusted for demographics, comorbidities, and labs.

Results

Among 8,747 patients listed for heart transplant, 84.7% were from metropolitan, 8.6% micropolitan, and 6.6% rural settings. The 2018 UNOS policy was associated with earlier receipt of heart transplant for metropolitan [SHR 1.56 (95% CI: 1.46-1.66)] and micropolitan [SHR 1.48 (95% CI: 1.21-1.82)] populations, but not significantly for rural [SHR 1.20 (95% CI: 0.93-1.54)]; however, the interaction between policy and densities was not significant (p = .14). Policy changes were not associated with risk of death post-transplant [metropolitan: HR 1.04 (95% CI: 0.80-1.34); micropolitan: HR 1.10 (95% CI: 0.55-2.23); rural: HR 1.04 (95% CI: 0.52-2.08); interaction p = .99].

Conclusions

The 2018 UNOS heart transplant policy was associated with earlier receipt of heart transplant and no difference in post-transplant survival within population densities. Additional follow-up is needed to determine whether improvements are sustained.

中文翻译：

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2018 年 UNOS 心脏政策与大都市、小城市和农村地区移植结果之间的关系

背景

2018 年，联合器官共享网络 (UNOS) 扩大了心脏移植候选者与捐赠者匹配的半径，但不同人口密度的结果尚不清楚。我们试图确定政策变化是否与来自农村、小城市和大都市的患者的心脏移植等待时间或移植后死亡的差异有关。

方法

我们利用移植受者科学登记系统，对 2017 年 1 月至 2019 年 9 月期间列入心脏移植名单的美国成年患者进行了评估，并随访至 2020 年 3 月。患者按家庭邮政编码分为大都市、小都市或农村地区。Fine、Gray 和 Cox 模型分别用于估计以死亡或从移植名单中删除作为竞争事件的心脏移植的亚分布风险比 (SHR)，以及 UNOS 政策前后人口密度内移植后死亡的 HR更改日期为 2018 年 10 月 18 日。根据人口统计、合并症和实验室对分析进行了调整。

结果

在 8,747 名接受心脏移植的患者中，84.7% 来自大都市，8.6% 来自小城市，6.6% 来自农村。2018 年 UNOS 政策与大都市 [SHR 1.56 (95% CI: 1.46-1.66)] 和小城市 [SHR 1.48 (95% CI: 1.21-1.82)] 人群较早接受心脏移植有关，但对于农村 [ SHR 1.20（95% CI：0.93-1.54）]；然而，政策和密度之间的相互作用并不显着（p  = .14）。政策变化与移植后死亡风险无关[大城市：HR 1.04（95% CI：0.80-1.34）；小都市：HR 1.10（95% CI：0.55-2.23）；农村：HR 1.04（95% CI：0.52-2.08）；相互作用p  = .99]。

结论

2018 年 UNOS 心脏移植政策与较早接受心脏移植有关，并且人口密度内移植后存活率没有差异。需要额外的后续行动来确定改进是否持续。