肾移植数量与结果的市场竞争及密度的时间分析

Adler Joel T, Yeh Heidi, Markmann James F, Nguyen Louis L

1 Center for Surgery and Public Health, Brigham and Women's Hospital, Boston, MA. 2 Division of Transplant Surgery, Department of Surgery, Massachusetts General Hospital, Boston, MA. 3 Division of Vascular and Endovascular Surgery, Department of Surgery, Brigham and Women's Hospital, Boston, MA.

Transplantation. 2016 Mar;100(3):670-7. doi: 10.1097/TP.0000000000000851.

BACKGROUND

Kidney transplant centers are distributed unevenly throughout 58 donor service areas (DSAs) in the United States. Market competition and transplant center density may affect transplantation access and outcomes. We evaluated the role of spatial organization of transplant centers in conjunction with market competition in the conduct of kidney transplantation.

METHODS

The Scientific Registry of Transplant Recipients was queried for market characteristics associated with kidney transplantation between 2003 and 2012. Market competition was calculated using the Herfindahl Hirschman Index. Kidney transplant centers were geocoded to measure spatial organization by the average nearest neighbor (ANN) method. Kidney quality was assessed by kidney donor risk index. A hierarchical negative binomial mixed effects model tested the relationship between market characteristics and annual kidney transplants by DSA.

RESULTS

About 152,071 kidney transplants were performed at 229 adult kidney transplant centers in 58 DSAs. Greater market competition was associated with kidney transplant center spatial clustering (P < 0.001). In multivariable analysis, more kidney transplant centers (incidence rate ratio [IRR], 1.04; P = 0.005), 100 more new listings (IRR, 1.02; P = 0.003), 100 more deceased donors (IRR, 1.23; P < 0.001), 100 more new dialysis registrants (IRR, 1.01; P < 0.001), and higher kidney donor risk index (IRR, 1.98; P < 0.001) were associated with increased kidney transplants.

CONCLUSIONS

After controlling for market characteristics, larger numbers of kidney transplant centers were associated with more kidney transplants and increased utilization of deceased donor kidneys. This underlines the importance of understanding geography as well as competition in improving access to kidney transplantation.

背景

在美国58个供体服务区（DSA）中，肾脏移植中心分布不均。市场竞争和移植中心密度可能会影响移植机会和结果。我们评估了移植中心的空间组织与市场竞争在肾脏移植过程中的作用。

方法

查询移植受者科学登记处，获取2003年至2012年期间与肾脏移植相关的市场特征。使用赫芬达尔-赫希曼指数计算市场竞争。通过平均最近邻（ANN）方法对肾脏移植中心进行地理编码，以测量空间组织。通过肾脏供体风险指数评估肾脏质量。采用分层负二项混合效应模型测试DSA的市场特征与年度肾脏移植之间的关系。

结果

在58个DSA的229个成人肾脏移植中心共进行了约152,071例肾脏移植。更大的市场竞争与肾脏移植中心的空间聚集相关（P < 0.001）。在多变量分析中，更多的肾脏移植中心（发病率比[IRR]，1.04；P = 0.005）、多100个新登记病例（IRR，1.02；P = 0.003）、多100个已故供体（IRR，1.23；P < 0.001）、多100个新透析登记患者（IRR，1.01；P < 0.001）以及更高的肾脏供体风险指数（IRR，1.98；P < 0.001）与肾脏移植增加相关。