Allan B. Massie, PhD, is an associate professor in the Department of Surgery and an associate professor in the Department of Population Health at NYU Langone.

Allan B. Massie, PhD

Don’t Forget to Follow Up: Kidney Transplant Referral Is Only the Beginning

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.

Can Transplant Center Referral Impact Kidney Transplant Evaluation?

Why Fewer Than Half of Referred Patients Reach Kidney Transplant Evaluatio

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.

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. 

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

Videos

NYU Langone’s Conor Donnelly, Allan Massie, and Michal Mankowski explain why follow-up after kidney transplant referral is critical to improving access.

Don’t Forget to Follow Up After Kidney Transplant Referral

A referral for kidney transplantation is only the beginning of a nephrologist's journey with their patient. A recent study from NYU Langone identified that among more than 720,000 patients referred for kidney transplantation, nearly half never initiated evaluation. One of the strongest predictors of whether patients progressed? The transplant center to which they were referred.

"We've learned that not all transplant centers are created equal, and in fact, the transplant center is one of the most important variables determining whether or not a patient actually makes it," Allan B. Massie, PhD, an associate professor in the Departments of Surgery and Population Health at NYU Langone, told 

For nephrologists, particularly those practicing in metropolitan areas with multiple transplant programs, Massie said referral destination should be viewed as an important clinical decision. Investigators identified substantial variation in how quickly transplant centers move patients through evaluation, suggesting differences in center workflows, available resources, and patient support may influence whether referred patients ultimately reach the waitlist.

"You should be informed to which transplant center you're referring to, because that really makes a difference," Michal A. Mankowski, PhD, is a research assistant professor at the Department of Surgery at NYU Langone said.

Why Fewer Than Half of Referred Patients Reach Kidney Transplant Evaluation

Leveraging Epic Cosmos EHR Data to Understand Kidney Transplant Attrition

Massie, Conor Donnelly, MD, Michal Mankowski, PhD, and colleagues analyzed Epic Cosmos, a database containing more than 300 million electronic health records from 1850 hospitals, making it the largest and most detailed cohort study to date examining where patients fall out of the kidney transplant process.

Among 720,348 referred candidates, the median age was 55 years (interquartile range [IQR], 42-64), 47% were White, 52% were male, 87% were English speaking, and 85% lived in urban areas.

The findings demonstrated substantial attrition across the kidney transplant pathway. 

10% ultimately underwent kidney transplantation.

Among patients who initiated evaluation, the median (IQR) time from referral to evaluation initiation was two (1-4) months. Among patients who were waitlisted, the median (IQR) time from evaluation initiation to waitlisting was four (2-9) months.

For centers documenting reasons patients did not progress to evaluation, the most common reasons included not meeting transplant criteria or not being a candidate (18%), patient decision (13%), inability to contact the patient (12%), financial or insurance complications (7%), and death (4%).

Beyond transplant center variation, investigators also identified several patient characteristics associated with a lower likelihood of initiating transplant evaluation. Patients who were never married (relative risk [RR], 0.94; 95% confidence interval [CI], 0.93-0.94), had severe obesity (RR, 0.70; 95% CI, 0.69-0.72), or lived in rural ZIP codes (RR, 0.98; 95% CI, 0.97-1.00) were less likely to begin evaluation. Investigators also observed reduced relative rates of transplantation among low-volume transplant centers (RR, 0.92; 95% CI, 0.88-0.96).

Why Are Patients Falling Through the Cracks?

According to Donnelly, the findings help identify patients most likely to fall out of the transplant process before they even begin evaluation.

"Our study identifies subpopulations of patients that are very likely to fall through the system," Donnelly told 

. "When you have a patient that you're referring to a transplant center that doesn't have private insurance, that is obese, that has comorbidities, these are patients that are very likely to fall through the system, and I think that they probably need support."

The transplant evaluation process itself can present significant barriers. Patients often undergo months of testing, imaging, cancer screenings, and repeated clinic visits while continuing dialysis treatment, creating numerous opportunities for patients to disengage before reaching the waitlist. Donnelly suggested earlier support, including assistance navigating financial, transportation, and logistical barriers, may help more patients successfully complete evaluation.

Small Barriers Can Become Large Disparities

While the study identified several patient- and center-level factors associated with lower progression through the transplant pathway, Massie said one of its most important findings was how those barriers accumulate over time.

"The most interesting thing that I learned is that all of these steps have to be overcome in order to get listed. It's really a cumulative process," Massie said. "If you look at patients that are ethnic minorities or socioeconomically disadvantaged or have other problems, at each stage there might be a very slight difference in risk of progression, but when you add it all up, it adds to an enormous difference."

Rather than focusing only on patients who reach the waitlist, these investigators said the findings emphasize the importance of examining the earliest stages of the transplant pathway, where the greatest attrition occurs.

"If we want to create an equitable system for patients, we need to look at these early steps as well," Massie said. "Patients are being lost here."

Although not every referred patient will ultimately qualify for transplantation, investigators emphasized that patients cannot be determined ineligible until they complete the evaluation process. Improving access to evaluation through earlier patient support and informed referral decisions may help more eligible patients ultimately reach the waitlist and receive a transplant.

“We strongly believe that way more people could have been waitlisted, and again, we see huge attrition just from being referred to start of evaluation,” concluded Manowski. 

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

Massie, Donnelly, and Mankowski discuss how transplant center choice shapes kidney transplant evaluation and access.

Why Fewer Than Half of Referred Patients Reach Kidney Transplant Waitlist

A recent study conducted by NYU Langone investigators revealed that nearly half of patients seeking a 

never initiate evaluation, according to data from > 1/3 of all US transplant centers.

By leveraging Epic Cosmos, a dataset of more than 300 million electronic health records from 1850 hospitals, investigators identified that of 720,348 patients referred for kidney transplantation, 48% initiated evaluation, 19% were waitlisted, and 10% ultimately underwent transplantation.

Conor Donnelly, MD, is a surgical resident at NYU Langone.

Michal A. Mankowski, PhD, is a research assistant professor at the Department of Surgery at NYU Langone.

"What our study finds is that the [transplant] center you go to, the characteristics about where you live and who you are impact whether or not you progress towards transplantation," lead author, Donnelly, told HCPLive in an interview. "A lot of the prior studies have looked at patients who have been already waitlisted and found that it's difficult to actually get transplanted, but our study looks at prior steps in this process and finds that it's very difficult for patients to get on the wait list."

Traditionally, studies have measured waitlist and transplant outcomes, but have not primarily tracked patients before the moment of waitlisting. Massie referred to the lack of national data on patient characteristics or outcomes prior to waitlisting as a "black box."

For the first time, investigators had access to national data that could provide insight into the process of the 4 stages of kidney transplants: referral, evaluation, waitlist, and transplant.

Using statistical models, they analyzed the impact of a wide range of factors, from age and sex to geographic location and medical history, on the progressive steps in the process.

Additionally, investigators examined social vulnerability, a measure of how a person's living conditions, such as poverty, lack of transportation, and unstable housing, may disadvantage them when they're trying to get care.

If Patients Need a Kidney Transplant, Why Aren't They Getting One?

Donnelly, Massie, Mankowski, and colleagues identified several patient characteristics that were associated with reduced rates of evaluation initiation. These include individuals who were never married (Relative Risk [RR] 0.94; 95% Confidence Interval [CI], 0.93 to 0.94), patients with severe obesity (RR, 0.70; 95% CI, 0.69 to 0.72), and those residing in rural zip codes (RR, 0.98; 95% CI, 0.97 to 1.00).

Furthemore, patients who identified as older, of reduced socioeconomic status, and those who spoke Spanish as their first language were especially unlikely to progress. Patients treated at small centers or at programs in the South were similarly unlikely to progress.

In centers with documentation for nonprogression to evaluation, 18% of reasons for removal included not meeting criteria/not a candidate, 13% were patient decisions, 12% were unable to contact, 4% were death, and 7% were financial/insurance complications.

How Can Nephrologists Help Patients Get Waitlisted For Kidney Transplants?

"When we're finding that less than half of patients are even evaluated, then nephrologists need to recognize that that referral isn't the end of the line," Massie said in an interview with HCPLive. "They can follow up with patients, they can see if patients are having practical barriers, if they're unable to get in contact with the transplant center, if they have logistical barriers to making an appointment happen."

Once a referral occurs, Massie and colleagues encourage nephrologists to take the extra step of following up with patients and transplant centers to monitor patient outcomes.

Editor’s Note: Connelly, Mankowski, and Massie report no relevant disclosures. 

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. 

Most People Seeking a Kidney Transplant Never Reach the Waitlist. (2026). NYU Langone News. 

https://nyulangone.org/news/most-people-seeking-kidney-transplant-never-reach-waitlist

Nearly half of kidney transplant candidates never start evaluation with access barriers varying by patient background.



Allan B. Massie, PhD

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