Clinical lung and heart/lung transplantation
Lung allocation in the United States, 1995–1997: an analysis of equity and utility

https://doi.org/10.1016/S1053-2498(00)00151-0Get rights and content

Abstract

Background: Waiting time for organ transplantation varies widely between programs of different sizes and by geographic regions. The purpose of this study was to determine if the current lung-allocation policy is equitable for candidates waiting at various-sized centers, and to model how national allocation based solely on waiting time might affect patients and programs.

Methods

UNOS provided data on candidate registrations; transplants and outcomes; waiting times; and deaths while waiting for all U.S. lung-transplant programs during 1995–1997. Transplant centers were categorized based on average yearly volume: small (≤£ 10 transplants/year; n = 46), medium (11–30 transplants/year; n = 29), or large (>30 transplants/year; n = 6). This data was used to model national organ allocation based solely on accumulated waiting time for candidates listed at the end of 1997.

Results

Median waiting time for patients transplanted was longest at large programs (724–848 days) compared to small and medium centers (371–552 days and 337–553 days, respectively) and increased at programs of all sizes during the study period. Wait-time–adjusted risk of death correlated inversely with program size (365 vs 261 vs 148 deaths per 1,000 patient-years-at-risk at small, medium, and large centers, respectively). Mortality as a percentage of new candidate registrations was similar for all program categories, ranging from 21 to 25%. Survival rates following transplantation were equivalent at medium-sized centers vs large centers (p = 0.50), but statistically lower when small centers were compared to either large- or medium-size centers (p ≤ 0.05). Using waiting time as the primary criterion for lung allocation would acutely shift 10 to 20% of lung-transplant activity from medium to large programs.

Conclusions

1) Waiting list mortality rates are not higher at large lung-transplant programs with long average waiting times. 2) A lung-allocation algorithm based primarily on waiting-list seniority would probably disadvantage candidates at medium-size centers without improving overall lung-transplant outcomes. 3) If fairness is measured by equal distribution of opportunity and risk, we conclude that the current allocation system is relatively equitable for patients currently entering the lung-transplant system.

Section snippets

Materials and methods

All lung transplantation registrations (listings), deaths while waiting, and transplant procedures performed in the United States between January 1, 1995 and December 31, 1997 and reported to UNOS were analyzed.

Eighty-one lung-transplant centers were active during this time period. The average number of lung transplants performed (activity) during the 3 years of the study was used to categorize lung-transplant centers. Centers were considered small if they performed ≤£ 10 transplants/year (n =

Results

Figure 1 displays the number of new patient registrations for lung transplantation in the United States during the 3-year time period 1995–1997, by center size. The number of patients newly listed at medium-sized programs has grown slightly, whereas the number of new registrations has remained fairly constant at small and large programs. Approximately half of all newly registered candidates are listed at medium-sized transplant centers.

Between 1995 and 1997, 22% (550/2529) of all lung

Discussion

Disparity in waiting times among transplant centers was one of the predominant factors motivating the DHHS initiative to revamp the U.S. transplant-allocation system. Our data confirm the perception that large lung-transplant programs have longer wait times than medium- and small-size programs. We next asked whether longer wait time at large programs translated into higher risk of death while waiting. We found that for lung transplantation, when adjusted for years at risk, candidates at small-

Acknowledgements

This study was funded in part by the U.S. Department of Health and Human Services, Health Resources and Services Administration, Office of Special Programs, Division of Transplantation, under contract numbers 240-97-0001 and 240-97-0002, for the operation of the Organ Procurement and Transplantation Network and the U.S. Scientific Registry of Transplant Recipients.

References (22)

  • New transplant rules: life or death choices. San Francisco Chronicle. April 5,...
  • Cited by (0)

    View full text