Kidney Week

Abstract: TH-OR072

Effect of Low Muscle Strength and CT-Defined Myopenia on the Performance of GFR Estimating Equations in Elderly Patients with Cancer

Session Information

• Onconephrology: Updates, Therapies, and Mechanisms
  November 06, 2025 | Location: Room 371A, Convention Center
  Abstract Time: 05:50 PM - 06:00 PM

Category: Onconephrology

• 1700 Onconephrology

Authors

• Costa e Silva, Veronica Torres, Universidade de Sao Paulo Instituto do Cancer do Estado de Sao Paulo, São Paulo, SP, Brazil

Veronica Torres Costa e Silva, MD, PhD

• Sise, Meghan E., Massachusetts General Hospital, Boston, Massachusetts, United States

Meghan E. Sise, MD, MS

• Inker, Lesley Ann, Tufts Medical Center, Boston, Massachusetts, United States

Lesley Ann Inker, MD, MS, FASN

• Strufaldi, Fernando Louzada, Universidade de Sao Paulo Instituto do Cancer do Estado de Sao Paulo, São Paulo, SP, Brazil

Fernando Louzada Strufaldi, MD

• Mantz, Lea, Massachusetts General Hospital, Boston, Massachusetts, United States

Lea Mantz

• Ouyang, Tianqi, Massachusetts General Hospital, Boston, Massachusetts, United States

Tianqi Ouyang, MPH

• Caires, Renato A., Universidade de Sao Paulo Instituto do Cancer do Estado de Sao Paulo, São Paulo, SP, Brazil

Renato A. Caires, MD

• Sapienza, Marcelo Tatit, Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo, São Paulo, SP, Brazil

Marcelo Tatit Sapienza, MD, PhD

• Burdmann, Emmanuel A., Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo, São Paulo, SP, Brazil

Emmanuel A. Burdmann, MD, PhD

• Fintelmann, Florian J., Massachusetts General Hospital, Boston, Massachusetts, United States

Florian J. Fintelmann, MD

Background

Estimated glomerular filtration rate(eGFR) equations based on serum creatinine(Scr)(eGFRcr) combined(eGFRcrcys) or not with serum cystatin C(Scys) present worse accuracy in patients with reduced muscle mass(myopenia). It's unknown if reduced muscle activity/ function can impact eGFR estimation. This analysis aims to evaluate the impact of low muscle strength(MS) associated or not with myopenia, defined by computed tomography(CT), on the performance of the CKD-EPI equations without race based on Scr and Scys in elderly patients(pts) with cancer

Methods

We included adult pts undergoing treatment for solid tumors between May 2017 and October 2017 and an abdominal CT scan within 90 days of measured GFR(mGFR) using the plasma clearance of ⁵¹Cr-EDTA. Skeletal muscle index(SMI) was defined as cross-sectional skeletal muscle area[cm²] divided by the square of the patient's height[m²]. Myopenia was defined as SMI < 39 cm²/m² and < 55 cm²/m² for women and men, respectively. Low MS(abnormal grip strength OR chair stand tests) and sarcopenia(myopenia combined with low MS) were defined according to the 2019 European consensus for sarcopenia

Results

Of 213 included pts(61% men, mean age 69[6.2] y), 46, 47, and 22% had myopenia, low MS, and sarcopenia, respectively. Median mGFR was 67(54 - 80) ml/min/1.73 m². Pts with myopenia, low MS and those with sarcopenia had large eGFRcr overestimation and poor accuracy. In non-myopenic pts, eGFRcr presented large bias in the case of low MS while those with normal strength had small bias for eGFRcr. eGFRcrcys improved GFR estimation in all assessed sub-groups(Table).

Conclusion

This is the first study to demonstrate that reduced MS is associated with large bias and poor accuracy for eGFRcr in paitents with normal muscle mass. MS evaluation can be easily incorporated in clinical practice to identify pts who may benefit from more accurate GFR evaluation, such as eGFRcrcys and measured GFR.

Funding

• Government Support – Non-U.S.

Digital Object Identifier (DOI)

• doi: 10.1681/ASN.202530zkqxr8