Creatinine and Cystatin C: A Measure of Renal Function in Men With Testosterone-Induced Muscle Hypertrophy

Creatinine (Cr) is often used as a standalone gold standard marker of kidney function. Cystatin C (Cys C) is a less physiologically labile marker of renal function, particularly in certain subgroups. Herein, we analyze trends in cystatin C as compared to creatinine in men on testosterone replacement...

Full description

Saved in:
Bibliographic Details
Main Authors: Rani Ashouri, Amica Lertkitcharoenpon, Michael Maidaa, Bobby Brunner, Oscar Velazquez, Larry Lipshultz, Kevin Campbell
Format: Article
Language:English
Published: SAGE Publishing 2024-10-01
Series:American Journal of Men's Health
Online Access:https://doi.org/10.1177/15579883241286654
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Creatinine (Cr) is often used as a standalone gold standard marker of kidney function. Cystatin C (Cys C) is a less physiologically labile marker of renal function, particularly in certain subgroups. Herein, we analyze trends in cystatin C as compared to creatinine in men on testosterone replacement therapy with varying body mass indices and percent body fat (PBF). This retrospective analysis observes 227 men with testosterone-induced muscle hypertrophy who visited a men’s health tertiary care clinic. All participants were characterized as competitive or recreational athletes. In patients with a normal body mass index (BMI), there was no clinically significant correlation between Cr and Cys C. Slight correlation was seen with overweight ( R 2  = .27) patients ( p < .0001) and obese ( R 2  = .29) patients ( p < .0001). Patients with PBF of 0%–10% ( n  = 22) exhibited minimal ( R 2  = .23) positive correlation between Cys C and Cr ( p  = .03). Positive correlation between Cys C and Cr in patients with PBF of 10%–20% was clinically negligible ( R 2  = .17, n  = 87), modest ( R 2  = .49) in patients with PBF of 20%–30% ( n  = 42), and evident ( R 2  = 1.00) in patients >30% ( n  = 3) ( p < .0001, respectively). Cystatin C measurements display less variance compared with creatinine at differing BMI distinctions. At the upper limit of BMI or PBF in our patient population, cystatin C exhibits minimal to moderate variability compared with creatinine.
ISSN:1557-9891