Mortality From Time of Listing for Transplantation as an Indicator of Candidate Outcomes(ADDED 9/22/04)
Steven D. Nathan, MD Context: Survival after transplantation has traditionally been the statistic most closely scrutinized as to the efficacy of the procedure and a program's performance. We propose that mortality from the time of listing is a more significant outcome measure for potential transplant candidates. We present our lung transplant program's outcomes using this measure. Discussion Survival statistics after transplantation are frequently the most prominent statistic presented to patients when they are being evaluated for and educated about transplantation. To place osttransplant survival statistics in the appropriate context, these data need to be viewed in conjunction with that of survival without transplantation. At the time of the evaluation, the most relevant statistic to prospective transplant candidates may be their survival from listing, because survival after transplantation does not in any way account for their prospects of ever receiving a transplant. There are 3 components to the composite statistic of postlisting survival, including mortality from the underlying primary disease without transplantation, mortality after transplantation for their primary disease, and the inherent waiting time on the local transplant list. The composite outcome is weighted in the direction of posttransplant survival for programs with short waiting times, whereas it is weighted in the direction of survival from the underlying primary disease for programs with longer waiting times. The 3 components of this weighted number should be viewed individually. For transplant programs in which the survival after listing is better for patients who have not received a transplant versus transplant recipients, this enhanced survival can then mean a number of things. Transplantation might not confer a survival advantage for the particular underlying primary disease being scrutinized (such as Eisenmenger syndrome). Also, the program's posttransplant survival rates might be suboptimal or, lastly, patients might be listed too early. This does, however, also depend on at what point osttransplant survival is being assessed. A significant percentage of the overall post-transplant mortality occurs within the first few weeks to months.[1] Therefore, the survival rate with or without a transplant early after transplantation might indicate that transplantation is disadvantageous from a survival standpoint. However, after the first few months, the crossover occurs and the transplant recipients' survival surpasses the survival of the patients who have not received a transplant. The greater the survival benefit, the earlier the crossover. In previous studies in which this type of analysis has been performed, most patient groups have been shown to have a survival benefit from lung transplantation, except possibly the COPD an d Eisenmenger syndrome subgroups. "If you do have a transplant within the first year after your listing, your likelihood of survival is 3-fold higher than if you don't have a transplant." This approach would also likely be useful in assessing transplant outcomes for sicker patients in whom marginal donors are being considered. Although their posttransplant survival might not be as good as for patients who are in better shape, analysis of their survival in the context of what their survival might have been without transplant, a marginal benefit by standard measures might translate to a significant benefit. What might be the potential disadvantages of a system in which postlisting surv val is more closely scrutinized? Programs might be more inclined to list sicker patients who have little chance of surviving to transplantation, which would skew the nontransplantation survival against which their transplantation survival will be scrutinized. On the other end of the spectrum, programs might be less inclined to list patients too early because this might skew the survival benefit toward not having a transplantation. The consequences of the latter scenario are debatable; programs with lengthy lists will frequently list patients early because they recognize that these patients will have to "do time" on the list. However, the disadvantage of this process is that patients who present more acutely with conditions that carry worse prognoses might be listed behind patients who are in less need of a transplant. In summary, we believe that postlisting survival is a more applicable and valuable statistic to be presented to potential transplant candidates. It might also be beneficial for program comparisons and enable sicker patients to receive transplants with justification. We also speculate that this type of analysis might foster the development of an alternate list for marginal donors and recipients and thereby increase the donor pool. Such an approach might also prove useful for looking at the appropriate allocation of organs for different diseases.(Source: Progress in Transplantation)
OPTN/UNOS lung allocation program breathes new life into effort to save lives, improve patient outcomes (ADDED 9/23/04) Transplant News - By Jim Warren Editor & Publisher
In an attempt to breath life into a flawed allocation system, the Organ Procurement and Transplantation Network (OPTN)/United Network for Organ Sharing (UNOS) board of directors has adopted a new lung allocation scheme with a lofty goal of reducing deaths on the waiting list while improving patient outcomes. Three years in the making, the new system represents a groundbreaking change in the nation's organ allocation policy, which is intended to balance how long a patient will survive on the transplant waiting list with how long the patient will benefit by receiving the transplant. The first patients to be affected by the change, which will be known as transplant benefit, will be those waiting for a life-saving lung transplant. Candidates who are most urgently in need of a transplant and who are expected to receive the greatest survival benefit from the transplant will receive priority lung offers. Previous lung allocation policy based on priority on the amount of time candidates had waiting for a transplant. Under the new policy, which was unanimously adopted by the board, transplant candidates will instead receive priority for lung offers based on an individual determination of their waitlist urgency and the transplant benefit based on their own clinical diagnostic factors. "If lungs grew on trees, we wouldn't need to change but the current system is severely flawed," Thomas Egan, MD, chair of the OPTN/UNOS Lung Allocation Subcommittee, told the board. "It had to change and we simply can't satisfy all the people all the time." "This policy is the result of years of discussion among transplant professionals and patient advocates, and was developed using sophisticated analysis of the latest transplant data available," Egan explained. "We believe that adopting the concept of transplant benefit strengthens our stewardship over the precious gifts of donor organs given by donor families to patients dying of end-stage lung failure." Egan said the current lung allocation system, which encouraged patients to be listed too early, was "broken" which led in turn led to a high turndown rate at many centers. "How to end waiting time is difficult to do while incorporating it into a model of urgency and utility," he added. "Even if waiting time counts a little bit you will still have lots of patients [under the old system] who will not be considered potential candidates for a lung transplant by a center. This is the crux of the argument for the change." The new policy recognizes that young children and adolescents offer a unique challenge when it comes to receiving donated lungs. To address this challenge, under the new policy pediatric candidates under age 12 will continue to receive lung offers based on
their waiting time, will receive first priority for lungs from donors under age 12, and will have improved access to lungs from adolescent donors. Adolescent candidates (age 12-17) will be assigned first priority for adolescent lung offers. Because of the complexity of the new allocation scheme, the policy will be under constant revew to be "tweaked" or changed as the situation calls for. "We will study the effects of this policy on a regular basis and make needed refinements to ensure that it provides the greatest benefit to patients," Egan cautioned. "We plan to continually update factors that are important in determining risk of death while waiting for a lung transplant, as well as factors associated with improved transplant benefit." Implementation of the new lung allocation policy is not anticipated until early 2005, in order to allow for programming of the computerized organ matching system and notification of transplant professionals and transplant candidates, UNOS said in a press release. During the transition, easy-to-understand materials explaining the new system will be prepared for both professionals and patients. Transplant programs are urged to begin educating their patients right away about the coming change in policy. Egan emphasized that patients do not stay in one place on the list for an organ and they can move as their diagnostic information changes. It will be incumbent on the transplant center to monitor the patients and make changes as the severity of their illness increases. The new policy will mandate that centers update patient variables at regular intervals. The OPTN/UNOS plans to hold a national forum within 2 years of the implementation of the policy to discuss how the system is working and address changes that may be needed.
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