Kidney Week

Abstract: TH-PO921

Creatinine Filtration as an Indicator of Muscle Mass and Functional Status in Older Adults

Session Information

• Geriatric Nephrology: Innovations and Insights
  October 24, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Geriatric Nephrology

• 1300 Geriatric Nephrology

Authors

• Ferguson, Jacquelyn, University of Vermont The Robert Larner MD College of Medicine, Burlington, Vermont, United States

Jacquelyn Ferguson

• Levey, Andrew S., Tufts Medical Center, Boston, Massachusetts, United States

Andrew S. Levey, MD

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

Lesley Ann Inker, MD, MS

• Garimella, Pranav S., University of California San Diego, La Jolla, California, United States

Pranav S. Garimella, MD, MPH, FASN

• Ballew, Shoshana, NYU Langone Health, New York, New York, United States

Shoshana Ballew, PhD

• Oka, Tatsufumi, Osaka Daigaku, Suita, Osaka, Japan

Tatsufumi Oka, MD, PhD

• Potok, O. Alison, University of California San Diego, La Jolla, California, United States

O. Alison Potok, MD

Background

Low muscle mass is associated with frailty and mortality in older adults. Estimated creatinine (Cr) filtration, defined as the product of serum Cr by cystatin C-based glomerular filtration rate (eGFRCys) in mg/day/1.73m², has been associated with frailty and mortality. We hypothesized that lower Cr filtration would be associated with poor functional status and decreased muscle mass on imaging, in both men and women.

Methods

In the Health Aging Body Composition study, 2804 (91% of HABC) well-functioning community-living elders (aged 70-79) had serum Cr, cystatin C, functional status defined by the HABC physical performance battery HABCPPB (score 0=worst; 4=best), and appendicular lean mass (aLM) and fat free mass (FFM) on dual-energy X-ray absorptiometry (DXA). CKD-EPI 2012 and 2021 equations were used to calculate eGFRCys and eGFRCr-Cys respectively. Participants were stratified by sex and divided into Cr filtration tertiles. The association of Cr filtration with outcomes was assessed by linear regression.

Results

Mean(SD) age was 74(3) years, eGFRCr-Cys was 74(17) mL/min/1.73m², Cr filtration was 1049(246) mg/day/1.73m². Mean HABCPPB score, aLM and FFM were 2.3(0.5)points, 24(4) and 57(7)kg in men, and 2.1(0.5)points, 17(3) and 41(6)kg in women, respectively. Men and women in the highest vs lowest Cr filtration tertile walked faster (1.1(0.4) vs. 1.0(0.5)m/s for men; 1.0(0.4) vs. 0.8(0.5)m/s for women), and had stronger grip (40(8) vs. 35(7)kg for men; 24(6) vs. 21(5)kg for women).
Higher Cr filtration (per SD) was associated with significantly better HABCPPB performance, higher aLM and FFM in both sexes (Table).

Conclusion

Higher Cr filtration was associated with better functional status, higher aLM and FFM in both men and women. These findings suggest it might be used clinically as a measure of muscle mass and function in older adults.

Association of Cr filtration (per SD) with functional status and with body composition, stratified by sex.

adjusted for age, race, body mass index, study site, education, smoking, hypertension, diabetes, statin medication use, serum albumin, log(C-reactive protein)

Funding

• NIDDK Support