Combined Body Mass Index and Body Surface Area to Predict Post Kidney Transplant Outcomes in Patients With Obesity

Background. The prevalence of obesity is increasing in both the general and kidney failure populations. Severe obesity (body mass index [BMI] ≥ 40 kg/m2) is considered by many centers to be a barrier to kidney transplantation (KT). Obesity is typically defined using BMI. Body surface area (BSA) is n...

Full description

Saved in:
Bibliographic Details
Main Authors: Roxaneh Zaminpeyma, MSc, Louise Moist, MSc, MD, Kristin K. Clemens, MD, Michael Chiu, MD, Janet Madill, RD, PhD., Karthik Tennankore, MSc, MD, Amanda J. Vinson, MSc, MD
Format: Article
Language:English
Published: Wolters Kluwer 2025-06-01
Series:Transplantation Direct
Online Access:http://journals.lww.com/transplantationdirect/fulltext/10.1097/TXD.0000000000001807
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Background. The prevalence of obesity is increasing in both the general and kidney failure populations. Severe obesity (body mass index [BMI] ≥ 40 kg/m2) is considered by many centers to be a barrier to kidney transplantation (KT). Obesity is typically defined using BMI. Body surface area (BSA) is not considered, though may also be important. Methods. We examined post-KT adverse outcomes associated with obesity defined using combined BMI-BSA parameters in a cohort of adult KT recipients (living/deceased donor) across the United States (Scientific Registry of Transplant Recipients: 2000–2017). Recipient obesity was defined as BMI ≥30 kg/m2, or BSA ≥1.94 m2 in women and ≥2.17 m2 in men. We used multivariable cox proportional hazards or logistic regression models as appropriate to assess the association between BMI-BSA-defined obesity with death-censored graft loss, all-cause graft loss, and delayed graft function. Results. The final study included 242 432 patients; 77 556 (32.0%) had obesity based on BMI and 67 312 (28.6%) had obesity based on BSA. Compared to patients with a nonobese BMI and BSA, the adjusted risk of death-censored graft loss, all-cause graft loss, and delayed graft function was greatest when both BMI and BSA indicated obesity (adjusted hazard ratio 1.23, 95% confidence interval [CI]: 1.20-1.27, adjusted hazard ratio 1.09, 95% CI: 1.07-1.11, adjusted odds ratio 1.58, 95% CI: 1.53-1.63, respectively); a significantly greater risk than when BMI and BSA were discordant. Conclusions. Currently only BMI is considered when evaluating obesity-related KT risk; however, combined BMI-BSA obesity may better identify individuals at high risk of poor outcomes posttransplant than BMI alone.
ISSN:2373-8731