RESUMO
BACKGROUND: Multiple listing (ML) is a practice utilized to increase the potential for transplant but is controversial due to concerns that it disproportionately benefits patients with greater access to healthcare resources. RESEARCH QUESTION: Is there disparity in ML practices based on social deprivation in the United States and does ML lead to quicker time to transplant? STUDY DESIGN AND METHODS: A retrospective cohort study of adult (>18 years old) lung transplant candidates listed for transplant (2005-2018) was conducted. Exclusion criteria included heart only or heart and lung transplant and patients relisted during the observation period. Data were obtained from the UNOS Standard Transplant Analysis and Research File. The first exposure of interest was social deprivation index (SDI) with a primary outcome of ML status, to assess disparities between ML and SL participants. The second exposure of interest was ML status with a primary outcome of time to transplant, to assess whether implementation of ML leads to quicker time to transplant. RESULTS: 35,890 subjects were included in the final analysis, of whom 791 (2.2%) were ML and 35,099 (97.8%) were SL. ML participants had lower median level of social deprivation (5 units, more often female (60.0% vs 42.3%), and had lower median LAS (35.3 vs 37.3). ML patients were more likely to be transplanted compared to SL patients (OR=1.42, 95%CI [1.17-1.73]), but there was a significantly quicker time to transplant only for whom ML was early (within 6 months of initial listing) (sHR=1.17, 95%CI [1.04-1.32]). INTERPRETATION: ML is an uncommon practice with disparities existing between ML and SL patients on the basis of several factors including social deprivation. ML patients are more likely to be transplanted, but only if they ML early in their transplant candidacy. With changing allocation guidelines, it is yet to be seen how ML will change with the implementation of continuous distribution.
RESUMO
Lung transplantation lags behind other solid organ transplants in donor lung utilization due, in part, to uncertainty regarding donor quality. We sought to develop an easy-to-use donor risk metric that, unlike existing metrics, accounts for a rich set of donor factors. Our study population consisted of n = 26 549 adult lung transplant recipients abstracted from the United Network for Organ Sharing Standard Transplant Analysis and Research file. We used Cox regression to model graft failure (GF; earliest of death or retransplant) risk based on donor and transplant factors, adjusting for recipient factors. We then derived and validated a Lung Donor Risk Index (LDRI) and developed a pertinent online application (https://shiny.pmacs.upenn.edu/LDRI_Calculator/). We found 12 donor/transplant factors that were independently predictive of GF: age, race, insulin-dependent diabetes, the difference between donor and recipient height, smoking, cocaine use, cytomegalovirus seropositivity, creatinine, human leukocyte antigen (HLA) mismatch, ischemia time, and donation after circulatory death. Validation showed the LDRI to have GF risk discrimination that was reasonable (C = 0.61) and higher than any of its predecessors. The LDRI is intended for use by transplant centers, organ procurement organizations, and regulatory agencies and to benefit patients in decision-making. Unlike its predecessors, the proposed LDRI could gain wide acceptance because of its granularity and similarity to the Kidney Donor Risk Index.
