Why high BMI is a tall barrier blocking kidney procedures
Obesity is a factor that still blocks far too many kidney transplants, and data indicates that it’s time for a change in thinking.
“You’re doing everything we ask, but until the scale budges, we can’t add you to the waitlist.”
Many U.S. kidney-transplant programs still set a firm body-mass-index threshold — usually 38 to 40 kg/m² — before a patient can be listed for a transplant. That policy feels prudent on paper because extreme obesity can lengthen procedures and raise wound-complication risk. In daily practice, however, it creates an invisible wall that keeps thousands of dialysis patients in limbo.
My doctoral project focused on high BMI-transplant candidates at the Medical University of South Carolina (MUSC). MUSC’s three-year review of 118 high-BMI transplant candidates (Table 2) is telling. About 77 percent of the cohort were Black, two-thirds were women, and only 28 percent ever reached the waitlist.
Those numbers confirm what national surveillance also shows: severe obesity is common among people of color, particularly African American women, and a strict BMI rule most significantly impacts that group.
Characteristics of high BMI patients referred to bariatrics who were transplanted vs. those who were not.
Policy vs. evidence
Early surgical series linked class-III obesity to higher peri-operative complications; those findings drove the BMI cut-offs that are still in use today.
However, 20 years of newer data tell a more nuanced story. Modern cohorts report no significant gap in long-term graft survival or mortality after heavier patients receive a kidney, and minimally invasive approaches have further reduced operative risk. The gap that does matter lies in access, not outcomes.
Dialysis keeps patients alive, but five-year survival barely tops 50 percent, and Medicare pays about $246 per treatment day. Our data makes the point. Candidates who secured bariatric surgery reached transplant 230 days sooner than peers who struggled with diet and exercise alone; the longer path translates into $56,000 in avoidable dialysis spending per patient.
Cost savings estimates
Because obesity and kidney disease intersect so sharply in Black women, a blanket BMI rule without robust weight-loss support essentially acts as a structural filter: it weeds out the very population already carrying the highest disease burden.
Rethinking the ‘first, lose weight’ ritual
What, then, does a more patient-centered approach look like?
It begins the moment a nephrologist first considers transplant. Instead of handing the patient a generic diet sheet, the clinic can bring a bariatric surgeon to the same exam room or virtual room during the initial work-up so clinically appropriate surgical options are on the table from Day 1.
At that same visit, teams can walk patients through shared-decision aids that balance surgical risk against dialysis-time risk, giving families a realistic sense of trade-offs rather than a vague “come back lighter” directive.
For many candidates, the next barrier is financial. That’s why programs are pushing payers to classify pre-transplant weight-loss interventions as medically necessary, not elective.
Finally, geography matters. Rural Carolinians in our cohort often lived three hours from Charleston. Telehealth and rotating outreach clinics enable them to complete nutrition visits or postoperative checks without a lengthy drive — another small but crucial improvement.
A new value-based backdrop
CMS soon will pay transplant centers under the Increasing Organ Transplant Access (IOTA) model, which rewards faster time-to-transplant and durable patient outcomes. Under IOTA, every extra month a candidate sits in dialysis tallies against the hospital’s performance. A BMI policy that slows listing now carries direct financial consequences, providing a timely nudge to modernize.
In the following piece, we will delve into the MUSC data, comparing surgical weight loss with lifestyle-only attempts, tracing how each pathway affects BMI, listing odds and, ultimately, transplant success. The numbers leave little doubt that proactive, integrated weight management is not a luxury but a necessity.
Delay, inequity, and wasted healthcare dollars are the unavoidable byproducts of the status quo. Modernizing approaches by embedding bariatric expertise, aligning payers and leveraging telehealth, offers patients a shorter, safer road to the kidney they need. No one should die on dialysis simply because of a number on the scale.
Zachary W. Sutton, DHA, MS, MSPAS, PA-C, DFAAPA, FACHDM, is transplant program coordinator and transplant advocate at MUSC Health.