Nearly half of patients referred for kidney transplantation never begin the evaluation process required to be considered for a new organ, according to a new study from NYU Langone Health, highlighting the need for continued follow-up and support after referral.

In the largest and most detailed study to date, using Epic Cosmos, a dataset of more than 300 million electronic health records from over 1,850 hospitals, examining attrition throughout the kidney transplant pathway, investigators found that social vulnerability, severe obesity, patient characteristics, and transplant center factors may influence whether patients progress from referral to evaluation, waitlisting, and transplantation.

Using data from 720,348 adults referred for kidney transplantation, researchers found that 48% of patients never initiated an evaluation, while only 19% completed the evaluation process and reached the waitlist.

“We really learned from this study that every stage matters. Nephrologists have to follow through, not just make a referral,” Allan B. Massie, PhD, associate professor in the Departments of Surgery and Population Health at NYU Grossman School of Medicine, told HCPLive.

Factors Associated With Lower Progression Through the Transplant Pathway

The study identified several factors associated with a reduced likelihood of advancing through the transplant pathway, including being unmarried, having severe obesity, living in rural areas, or experiencing greater socioeconomic vulnerability.

Investigators also found differences based on transplant center characteristics, with patients treated at smaller centers or programs in certain regions less likely to advance through the process.

Severe obesity was one factor associated with lower progression through the transplant pathway. Investigators emphasized that the findings were specific to severe obesity rather than obesity more broadly.

“It’s important to recognize severe obesity as a factor. We are seeing a 70% decrease in the rate of transplantation among patients with severe obesity, so it’s just a population to identify and be aware of for nephrologists, especially,” said Conor Donnelly, MD, resident and PhD student in the Department of Surgery at NYU Grossman School of Medicine.

Although some patients may appropriately be excluded from transplantation because of medical concerns, investigators emphasized that many patients may fail to progress for reasons unrelated to medical eligibility.

“It’ll never be the case that every patient referred for transplantation is going to be listed and transplanted. There are some patients who are genuinely ineligible for medical reasons,” Massie said. “However, at the same time, our study leads us to believe that many patients are failing to progress for reasons other than medical criteria.”

What Can Clinicians and Transplant Centers Do Differently?

Investigators emphasized that improving access to transplantation will require support throughout the entire process, beginning soon after referral.

“Transplant centers have to lower barriers to getting appointments, establishing a relationship with the transplant team to identify patient-specific barriers and help them overcome them,” Massie said. “It really depends on a team coming together to provide holistic care for the patient.”

Support may include helping patients navigate appointments, transportation challenges, and other logistical barriers that emerge early in the evaluation process.

“When you’re looking at support, whether it’s helping patients with transportation or helping them with costs associated with the whole process, it’s important to understand that these costs are incurred early on,” Donnelly said. “Supporting them involves identifying these patients that could benefit from it, and then supporting them at these earlier stages.”

Mankowski also emphasized the importance of education and communication as patients enter a complex and unfamiliar process.

“Education and support are important because the process is very complex, and often patients are in touch with a completely new team. They have to do a lot of different testing, probably now in different places, and interact with teams that they never interacted with before,” said Michal A. Mankowski, PhD, assistant professor in the Department of Surgery at NYU Grossman School of Medicine. “Staying in touch and helping navigate, at least early on, will be a great win.”

The investigators noted that future interventions will likely need to be tailored to individual populations, as barriers may differ across geographic regions and patient communities. However, they emphasized that identifying where patients are lost in the transplant pathway is an important first step toward improving access.

“Tracking is critical to understanding how this process evolves over time. Our study shows that this is not getting better, and continuing to monitor these trends will help us build a better system, which is what we all want to do,” Donnelly said.

Editor's Note: Donnelly, Mankowski, and Massie report no relevant disclosures.

References

1. Donnelly, C. B., Patel, S. S., Husain, S. A., Gentry, S. E., Patzer, R. E., Lonze, B. E., Bae, S., Axelrod, D., Orandi, B. J., McAdams-DeMarco, M. A., Segev, D. L., Massie, A. B., & Mankowski, M. A. (2026). Evaluating Barriers to Kidney Transplantation in the United States. Journal of the American Society of Nephrology. https://doi.org/10.1681/asn.0000001162

2. Most People Seeking a Kidney Transplant Never Reach the Waitlist. NYU Langone News. Published 2026. Accessed July 15, 2026. https://nyulangone.org/news/most-people-seeking-kidney-transplant-never-reach-waitlist