Patients with obesity and end-stage renal disease may finally be able to access life-saving kidney transplants

Patients with obesity and end-stage renal disease (ESRD) who were previously not eligible for kidney transplantation due to elevated Body Mass Index (BMI) may have new therapeutic options, according to a collaborative study performed by the bariatric and transplant teams at Tulane University School of Medicine in New Orleans, LA.^[]

The teams found that metabolic and bariatric surgery (MBS) offers a potential intervention for patients with obesity and ESRD, as reduced BMI improves metabolic health so that kidney transplantation becomes possible. 

Elevated BMI (more specifically, class II obesity) and ESRD are closely connected. High BMI often leads to a reduced estimated glomerular filtration rate (GFR), resulting in a higher incidence of ESRD.  As the authors of the study note, ESRD poses a “significant and pressing challenge to public health, with obesity emerging as a pivotal determinant impacting both patient outcomes and therapeutic avenues.”^[]

Corresponding study author Anil Paramesh, MD, MBA, FACS, Professor of Surgery, Urology, and Pediatrics and Director of Kidney and Pancreas Transplant Programs at Tulane University School of Medicine, tells MDLinx that, historically, many surgeons do not want to perform surgery on patients with ESRD and high BMI. Patients with obesity are told that they are too large for a transplant, Dr. Paremesh says. “Transplant centers are regulated by outcomes. The ask is to lose weight and come back. Patients need support to do that, though.”

A closer look at the study

The authors write that 183 patients—with an average age of 42.9—were initially referred to the bariatric team by the transplant team. Out of the referred patients, 36 underwent MBS,  20 underwent Roux-en-Y gastric bypass (RYGB) surgery, and 16 underwent sleeve gastrectomy (SG) surgery. Of these patients, 10 successfully underwent kidney transplantation, and another 15 were waitlisted.^[] 

The mean preoperative BMI of the RYGB group (75% female, 60% Black) was 49.1, while the SG group (56.2% female, 87.5 % Black) had a mean preoperative BMI of 44.1.^[]

Many of the patients had other comorbidities, including hypertension and obstructive sleep apnea. 22.2% of patients in the SG group had congestive heart failure (CHF), compared to only 5% of the  RYGB group.^[] 

The authors say that both the RYGB and SG surgical groups saw a “significant” reduction in BMI (an average of 27% at the time of transplant). “At 12 months post-surgery, patients in the RYGB had an average decrease in BMI greater than those in the SG group, suggesting a potentially more pronounced long-term effect on weight loss with RYGB in this cohort,” the authors note. The patients also saw further improvements in comorbid conditions, such as hypertension and diabetes.^[] 

To achieve success, the teams shared resources, including a common database, dieticians, and social workers, for easy communication and transition between the teams. Dr. Pararmesh says that the teams worked together to discuss things like medication, nutrition, and the arrangement of dialysis.^[]

The goal? “Having a close collaboration between bariatric and transplant teams,” Dr. Paramesh says. “Separate silos are a problem.” For example, bariatric teams offer their own dietary counseling, which may not reflect the recommendations from the transplant team.

In this case, he says, “[the teams] worked toward transplant and bariatric surgery at the same time.”.

Exploring the limitations

“While this approach shows promise, its accessibility remains limited,” the authors note. “[I]n the United States, many insurance payers mandate a trial of medical weight management prior to approving MBS, but centers that perform MBS could be reluctant to perform these procedures in these patients due to the potential high rate of complications and death.”^[]

More so, MBS isn’t widely available. Dr. Paramesh says that his center had to create its own program to facilitate transplantation in these patients—something he hopes other clinicians will do, too. “It does require collaboration and extra work to get this done, but it’s doable,” he says.

Dr. Paramesh and the two teams established the Collaborative for Obesity Research in Transplantation (CORT) initiative. He says that the goal is to establish a standard of care. “There is no standard of care. Our hope is to provide more data,” he says. 

Making transplantation accessible among this population of patients is also important, as it can help close racial gaps, Dr. Paramesh explains. 

“What prompted this was the increasing number of patients turned down for surgery—in their 30s and 40s but morbidly obese. Very few of them were able to lose weight,” Dr. Paramesh says. “Most of these patients were African American, increasing the healthcare disparities that already exist. Minorities and socially disadvantaged people often eat cheap, processed foods…not the healthier, more expensive foods.”

Ultimately, he urges better patient education—whether it’s around eating for kidney health or how to lose weight, for example. 

“Obesity is a disease,” he says. “I don’t think enough focus is given to obesity as a disease. More and more people are obese, with comorbidities. Education needs to start earlier.”