Submit your picks! | @NephMadness | @nephmadness.bsky.social | NephMadness 2025

Kelly Birdwell

Dr. Birdwell is a transplant nephrologist at Vanderbilt University Medical Center where she is focused on improving the health of kidney transplant recipients. Through her research and clinical activities, this overarching goal drives her passion to advance the field of kidney transplantation.

Competitors for the Obesity in Kidney Transplant Region

Team 1: Obesity in Kidney Transplant Donors

vs

Team 2: Obesity in Kidney Transplant Recipients

Image generated by Evan Zeitler using DALLE-E 3, accessed via ChatGPT at http://chat.openai.com, February 2025. After using the tool to generate the image, Zeitler and the NephMadness Executive Team reviewed and take full responsibility for the final graphic image.

Receiving a kidney transplant is a life-changing event. Gone are the days dedicated to dialysis sessions, ongoing fatigue, and a restricted diet to which even the most dedicated individuals have trouble adhering. Furthermore, we know that kidney transplantation is the kidney replacement therapy of choice, resulting in improved quality of life and greater survival compared to remaining on dialysis or the wait list. So, while there are lots of positives to be gained by receiving a kidney transplant, one item gained is not so positive… too many pounds, leading to obesity.

Many are familiar with the obesity paradox in dialysis. Compared to normal weight individuals, those with an increasing category of BMI have a survival advantage on dialysis. Post-transplantation, however, the tables are turned. Those patients with pre-existing obesity have worse post-transplant outcomes compared to their normal weight counterparts. These include increased mortality and death censored graft loss with increasing body mass index, as shown in large retrospective cohort studies. Given the increasing prevalence of obesity in our population, with greater than 30% of all kidney transplant recipients obese at the time of transplant, this is a common problem requiring attention both pre- and post-transplant to optimize long term kidney transplant outcomes. Additionally, post-transplant weight gain is common, with an average weight gain of 9 kg in the first 12 months.

So, what are the complications of this weighty problem? Obesity in the kidney transplant recipient packs a 1-2-3 punch, with post-surgical complications, effects on allograft function, and impact on long term patient survival by contributing to cardiovascular risk factors. In the post-transplant period, recipients with a BMI greater than 30 have increased odds of surgical site infections and are twice as likely to have wound healing issues.  Though studies don’t strongly support an association of obesity with acute rejection, delayed graft function is commonly reported. The information about long term graft survival is conflicting, though some studies suggest decreased allograft survival with BMI greater than 30, including two studies that used a mate- kidney analysis. Obesity contributes to several known cardiovascular risk factors in the post-transplant period including hypertension, post-transplant diabetes mellitus, dyslipidemia, inflammation, and metabolic syndrome. Even when controlling for these cardiovascular risk factors, obesity has been shown to be an independent predictor for cardiovascular disease post-transplant. The impact of this is significant, given that cardiovascular disease is the number one identified cause of patient death in persons with functioning kidney transplants.

With all this stated, it is still important to realize that obese kidney transplant recipients maintain improved survival compared to their wait listed counterparts, so kidney transplantation should still be pursued in this population. However, to improve short- and long-term outcomes, we should encourage wait listed candidates to enter transplant with a BMI less than 30 and support them post-transplant to prevent further weight gain. Lifestyle changes should always be supported, but for most people these effects will be modest. Medical weight loss via pharmacologic means has been revolutionized by the availability of the glucagon-like peptide-1 agonists (check out the #NephMadness 2024 Champion: Gila Monster). If these measures don’t work or are not tolerated, surgical weight loss has been shown to be effective and safe, both to get candidates on the wait list at an acceptable weight, as well as to provide suggested improvements in post-transplant outcomes in recipients.

So, there is nothing to lose by championing weight loss for Obesity in Kidney Transplant Recipients! We can work with our patients to gain better health and transplant outcomes.  The hardest step is deciding to commit to the change:

– Guest Post written by Kelly Birdwell

As with all content on the AJKD Blog, the opinions expressed are those of the author of each post and are not necessarily shared or endorsed by the AJKD Blog, AJKD, the National Kidney Foundation, Elsevier, or any other entity unless explicitly stated.

Click to read the Obesity in Kidney Transplant Region

Submit your picks! | @NephMadness | @nephmadness.bsky.social | NephMadness 2025