Kidney Week

Abstract: FR-PO1129

CT Psoas Muscle Density Independently Predicts Delisting Risk Beyond BMI and Functional Capacity in Kidney Transplant Candidates

Session Information

• Transplantation: Clinical - Transplant Access, Recipient Evaluation, Living Donors, Pregnancy, and More
  October 23, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Transplantation

• 2002 Transplantation: Clinical

Authors

• Vaske, Luke, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States

Luke Vaske

• Angle, Ethan, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States

Ethan Angle

• Wendland, Julia Rose, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States

Julia Rose Wendland

• Gao, Yubo, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States

Yubo Gao, PhD

• Sarrazin, Mary Vaughan, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States

Mary Vaughan Sarrazin, PhD

• Longo, Jude, Iowa City VA Medical Center, Iowa City, Iowa, United States

Jude Longo, MD

• Sanders, M. Lee, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States

M. Lee Sanders, MD, PhD, FASN

• Katz, Daniel, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States

Daniel Katz, MD

Background

BMI and functional capacity (METs) are standard measures used in transplant candidate evaluation. CT-based psoas Hounsfield unit (HU) measurement reflects muscle quality at the tissue level. Whether psoas HU provides independent information about delisting risk beyond BMI and METs — and whether it can be inferred from those standard measures — has not been established in kidney transplant candidates.

Methods

Among 184 Veterans listed for kidney transplantation with available CT imaging, psoas HU was correlated with BMI and METs using Pearson correlation coefficients. Linear regression models quantified the proportion of variance in psoas HU explained by BMI alone, METs alone, and both combined. Interaction terms between psoas HU and both BMI and METs were tested in logistic regression models predicting 5-year delisting.

Results

Statistically significant but weak associations were observed between psoas HU and both BMI (r=-0.32, p<0.001) and METs (r=0.25, p=0.0007). Linear regression demonstrated METs alone explained only 6.5% of variance in psoas HU (R2=0.065), BMI alone explained 11.2% (R2=0.112), and both combined explained only 15.6% (R2=0.156) — leaving 84.4% of muscle density variation unexplained. No significant interactions were observed between psoas HU and BMI or METs, indicating a consistent effect of psoas HU across BMI and METs levels. AIC-based selection identified psoas HU as an independent additive predictor of delisting in 7 of 9 optimal models, achieving AUC 0.826 on bootstrapped validation.

Conclusion

While psoas HU is modestly correlated with BMI and METs, these standard clinical measures explain less than 16% of the variation in muscle density. Psoas HU independently predicts 5-year delisting irrespective of body habitus or functional capacity, capturing clinically meaningful information that cannot be inferred from BMI or METs alone and supporting the need for direct CT-based muscle assessment in kidney transplant candidates.