Kidney Week

Abstract: SA-PO424

Performance of a Pure Metabolite Panel Estimate of GFR (accuGFR)

Session Information

• CKD: Estimating Equations, Incidence, Prevalence, Special Populations
  November 04, 2017 | Location: Hall H, Morial Convention Center
  Abstract Time: 10:00 AM - 10:00 AM

Category: Chronic Kidney Disease (Non-Dialysis)

• 302 CKD: Estimating Equations, Incidence, Prevalence, Special Populations

Authors

• Coresh, Josef, Johns Hopkins Medical Institutions, Baltimore, Maryland, United States

Josef Coresh,

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

Lesley Inker,

• Chen, Jingsha, Johns Hopkins Medical Institutions, Baltimore, Maryland, United States

Jingsha Chen,

• Eiriksdottir, Gudny, Icelandic Heart Association, Kopavogur, Iceland

Gudny Eiriksdottir,

• Gudnason, Vilmundur, Icelandic Heart Association, Kopavogur, Iceland

Vilmundur Gudnason,

• Torres, Vicente E., Mayo Clinic, Rochester, Minnesota, United States

Vicente E. Torres,

• Ford, Lisa, Metabolon, Inc. , RTP, North Carolina, United States

Lisa Ford,

• Oyaski, Maria, Metabolon, Inc. , RTP, North Carolina, United States

Maria Oyaski,

• Perichon, Regis, Metabolon, Inc. , RTP, North Carolina, United States

Regis Perichon,

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

Andrew S. Levey,

Background

We showed that panels of metabolites can provide an accurate estimate of glomerular filtration rate (GFR) without creatinine and demographic characteristics. We present a Laboratory Developed Test (LDT) to estimate GFR (accuGFR) and estimate its performance in subgroups where eGFRcr is less accurate. Study Population: GFR measurements (mGFR) on 3,236 individuals in the AASK, MDRD, AGES and the CRISP studies were divided randomly into a development sample (50%) and validation samples (25% complete, 25% unused backup).

Methods

Laboratory Methods: Stored (-70°C) serum specimens were subjected to targeted UPLC-mass spectrometry assays for 4 metabolites and serum creatinine (CV <5%). Data Analysis: accuGFR estimated using linear regression of log mGFR on log metabolites in the development sample. Performance measured using large errors (1-P30 and 1-P20, the percentage of estimates deviating from the mGFR by >30% and >20%). We compared the accuGFR to eGFR by CKD-EPI equations.

Results

mGFR spanned a wide range (mean 55, SD 26 ml/min/1.73m²). accuGFR based on 4 metabolites without demographics had substantially better accuracy than eGFRcr and eGFRcys but similar performance to eGFRcr-cys in the accuGFR development and validation samples. In subgroups where there is concern that eGFRcr may be inaccurate, accuGFR often outperformed even eGFRcr-cys, particularly for 1-P20.

Conclusion

accuGFR based on four metabolites without serum creatinine or demographics nearly halved the rate of large errors compared to eGFRcr and appears to be robust across a range of relevant subgroups. The utility of the accuGFR test based on a single blood draw should be tested in diverse clinical and research populations.