Related Experiment Video
Updated: Dec 13, 2025
The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis
Published on: March 17, 2010
Cystatin C and Muscle Mass in Patients With Heart Failure
Juan B Ivey-Miranda1, Lesley A Inker2, Matthew Griffin3
1Department of Heart Failure, Hospital de Cardiologia, Centro Medico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City, Mexico; Department of Internal Medicine, Section of Cardiovascular Medicine, Yale University School of Medicine, New Haven, Connecticut.
Insights
Estimated glomerular filtration rate (eGFR) from cystatin C may be inaccurate in heart failure (HF) patients due to muscle mass variations. Both cystatin C and creatinine-based eGFR require cautious interpretation in HF with body composition changes.
Area of Science:
- Nephrology
- Cardiology
- Clinical Biochemistry
Background:
- Heart failure (HF) and sarcopenia are associated with altered body composition.
- Creatinine-based estimated glomerular filtration rate (eGFRcr) accuracy is affected by muscle mass.
- Cystatin C-based eGFR (eGFRcys) is hypothesized to be less influenced by muscle mass.
Purpose of the Study:
- To assess the association between muscle mass and cystatin C levels.
- To evaluate the accuracy of eGFRcys compared to eGFRcr.
- To determine the association of eGFRcys with mortality in relation to muscle mass.
Main Methods:
- Included 293 patients admitted with heart failure.
- Muscle mass estimated using a creatinine excretion-based equation.
- Compared accuracy of eGFRcys and eGFRcr against measured creatinine clearance.
Main Results:
- Both cystatin C and creatinine levels increased significantly with higher muscle mass (P < .001).
- eGFRcys and eGFRcr overestimated measured creatinine clearance in individuals with lower muscle mass.
- eGFRcys underestimated measured creatinine clearance in individuals with higher muscle mass; eGFRcr did not.
- Neither eGFRcys nor eGFRcr showed association with mortality after adjusting for muscle mass (P > .19).
Conclusions:
- Cystatin C levels are associated with muscle mass in HF patients, potentially impacting eGFRcys accuracy.
- eGFRcys, similar to eGFRcr, may not provide reliable GFR estimations in HF patients with common body composition abnormalities.
- Results for eGFRcys in HF patients should be interpreted with caution due to muscle mass influence.
Background:
The estimated glomerular filtration rate (eGFR) from cystatin C (eGFRcys) is often considered a more accurate method to assess GFR compared with an eGFR from creatinine (eGFRcr) in the setting of heart failure (HF) and sarcopenia, because cystatin C is hypothesized to be less affected by muscle mass than creatinine. We evaluated (1) the association of muscle mass with cystatin C, (2) the accuracy of eGFRcys, and (3) the association of eGFRcys with mortality given muscle mass.
Methods And Results:
We included 293 patients admitted with HF. Muscle mass was estimated with a validated creatinine excretion-based equation. Accuracy of eGFRcys and eGFRcr was compared with measured creatinine clearance. Cystatin C and creatinine were 31.7% and 59.9% higher per 14 kg higher muscle mass at multivariable analysis (both P < .001). At lower muscle mass, eGFRcys and eGFRcr overestimated the measured creatinine clearance. At higher muscle mass, eGFRcys underestimated the measured creatinine clearance, but eGFRcr did not. After adjusting for muscle mass, neither eGFRcys nor eGFRcr were associated with mortality (both P > .19).
Conclusions:
Cystatin C levels were associated with muscle mass in patients with HF, which could potentially decrease the accuracy of eGFRcys. In HF where aberrations in body composition are common, eGFRcys, like eGFRcr, may not provide accurate GFR estimations and results should be interpreted cautiously.
Related Concept Videos
01:29Cardiomyopathy III: Hypertrophic Cardiomyopathy
01:29Heart Failure II: Pathophysiology
01:17Pathophysiology of Heart Failure
01:30Heart Failure IV: Classification and Diagnostic Evaluation
01:13Structure of Cardiac Muscles
Compared to skeletal muscles, cardiac muscle cells are small and mostly have a single nucleus. Additionally, they are usually...
01:27Heart Failure I: Introduction