Model Suggests Giving Kidneys to Patients on Dialysis a Better Use of Resources

A preemptive waiting list for kidney recipients is not the best use of scarce resources from a societal perspective, and giving kidneys to those receiving dialysis is more effective, according to recent findings that simulated the cases of 4 patients with renal disease.

The aim of the study, published in JAMA Network Open, was to examine patient outcomes and costs when a strategy diverts kidney organs from candidates receiving dialysis and instead gives it to those on a preemptive waiting list. To do this, the medical decision analytical model "followed" 4 patients:

• A patient on the preemptive waiting list receiving a kidney transplant
• A patient on the preemptive waiting list never receiving a transplant
• A waitlisted patient that has received dialysis and will receive a transplant
• A waitlisted patient receiving dialysis never receiving a transplant

Some assumptions were made for the model, including that the kidney transplanted was the same for both patients; patients in all cohorts were similar in age, sex, race and ethnicity, disease, comorbidity status, and insurance; mortality in patients on the preemptive waiting list was relatively higher compared with patients receiving a preemptive transplant; and mortality in patients who received a transplant after dialysis for less than 1 year was equal to mortality in patients receiving a transplant preemptively.

The baseline patient was aged 50 years, which was the mean age of preemptive patients transplanted with a kidney. Patients were excluded if they had a transplant after 65 years, as most of the preemptive recipients would be younger than 65 years.

The preemptive transplant recipient had 10.58 (95% CI, 10.36-10.80) QALYs and the preemptive patient never transplanted had 6.83 (95% CI, 6.67-6.99) QALYs in the simulated patient with a mean start age of 50 years, which was a gain of 3.75 (95% CI, 3.57-3.93) QALYs.

The patient who had a transplant from dialysis had 10.33 (95% CI, 10.21-10.55) QALYs whereas the dialysis patient that remained on the waiting list had 6.20 (95% CI, 6.04-6.36) QALYs, which is a gain of 4.13 (95% CI, 3.92-4.31) QALYs. The study found that preferential preemptive transplantation had –0.39 (95% CI, –0.59 to –0.29) QALYs and resulted in an added cost of $54,100 (95% CI, $44,100-$64,100) compared with allocation to a waiting list for those already receiving dialysis.

The difference was –0.67 (95% CI, –0.78 to –0.56) QALYs and had a higher net cost of $105,900 (95% CI, $89,700-$122,100) in a preemptive patient that was less likely to need dialysis. The benefit was –0.16 (95% CI, –0.25 to –0.07) QALYs at a net cost of $9200 (95% CI, $1000-$17,400) in patients who were more likely to need dialysis.

Patients who received dialysis for 3 to 4 years had 9.66 (95% CI, 9.44-9.88) QALYs whereas patients in the dialysis group who stayed on the waiting list had 5.92 (95% CI, 5.76-6.08) QALYs, with a benefit of 0.01 (95% CI, –0.13 to 0.15) QALYs for the patient receiving a preemptive transplant.

Net benefit favored preemptive transplantation (0.24 QALYs; 95% CI, 0.10-0.38) if the preemptive patient was more likely to need dialysis but there was a loss of net benefit (–0.27 QALYs; 95% CI, –0.40 to –0.14) if the patient was less likely to need dialysis.

There were some limitations to this study. Individual characteristics were not considered and therefore the results of this study should be confirmed with patient-level data analysis. The analysis was not aimed at determining the threshold for waitlisting patients. The study did not consider that a preemptive patient could be given a kidney based on matching criteria. A suggestion for preferentially allocating organs to patients receiving dialysis for less than a year rather than to patients receiving dialysis for more than a year was not given.

The researchers concluded that preemptive waitlisting may be a strategy that favors some groups over others.

“Rather than eliminating preemptive transplantation, restricting the list to those likely to be on dialysis within a year or who are highly sensitized may be an optimal approach, provided qual access can be assured for all,” the authors wrote.

Reference

Kiberd BA, Tennankore KK, Vinson AJ. Comparing the net benefits of adult deceased donor kidney transplantation for a patient on the preemptive waiting list vs a patient receiving dialysis. JAMA Netw Open. 2022;5(7):e2223325. doi:10.1001/jamanetworkopen.2022.23325